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Aira

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  • Japan
  • Caldera
  • 2024 CE
  •  
  • Country
  • Primary Volcano Type
  • Last Known Eruption
  •  
  • 31.5772°N
  • 130.6589°E

  • 1117 m
    3665 ft

  • 282080
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number
Most Recent Weekly Report: 6 March-12 March 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 4-11 March with nighttime crater incandescence. Very small eruptive events occasionally occurred during 4-8 March. An explosion at 0359 on 9 March produced an ash plume that rose 800 m above the crater rim and drifted SE, and ejected large blocks 1.3-1.7 km from the vent. Eruptive events at 1540 on 10 March and at 0532 on 11 March generated ash plumes that rose 1.2-1.3 km above the crater rim and drifted E. An ash plume from an explosion at 2132 on 11 March rose 1.4 km above the crater rim and drifted NE; large blocks were ejected 500-700 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


Most Recent Bulletin Report: January 2023 (BGVN 48:01) Citation IconCite this Report

Explosions, ash plumes, and ashfall during July-December 2022

Aira caldera is located in the northern half of Kagoshima Bay and contains the active post-caldera Sakurajima volcano near the southern tip of Japan’s Kyushu Island. Frequent historical eruptions have been recorded since the 8th century and have deposited ash on Kagoshima, one of Kyushu’s largest cities, 10 km W from the summit. The largest recorded eruption took place during 1471-76. The current eruption period began during late March 2017 and has more recently consisted of explosive events, eruption plumes, minor ashfall, and crater incandescence (BGVN 47:07). This report updates information from July through December 2022 using monthly activity from the Japan Meteorological Agency (JMA) and satellite data.

Thermal activity remained at low levels during the reporting period; only two anomalies were detected each month during late July and early August, and there was a brief period of no registered thermal data during mid-August through most of September (figure 132). After late October, the frequency of thermal anomalies increased slightly and up to two anomalies were observed in the Minamidake crater in Sentinel-2 infrared satellite imagery during the latter part of the year (figure 133).

Table 28. Number of monthly explosive events, days of ashfall, area of ash covered, and sulfur dioxide emissions from Sakurajima’s Minamidake crater at Aira during July-December 2022. Note that smaller ash events are not listed. Ashfall days were measured at Kagoshima Local Meteorological Observatory, and ashfall amounts represent material covering all the Kagoshima Prefecture. Data courtesy of JMA monthly reports.

Month Explosive events Days of ashfall Ashfall amount (g/m3) SO2 emissions (tons/day)
Jul 2022 12 6 28 1,400-3,200
Aug 2022 16 0 0 1,500-2,500
Sep 2022 23 14 53 1,900-2,400
Oct 2022 12 18 24 1,900-4,000
Nov 2022 5 10 9 700-1,900
Dec 2022 11 8 12 1,400-2,800
Figure (see Caption) Figure 132. Thermal activity at Sakurajima in the Aira caldera was relatively low during late July through December 2022, according to this MIROVA graph (Log Radiative Power). Two thermal anomalies were recorded during each month of late July and early August. No thermal activity was detected for a brief period during mid-August through most of September. The number of anomalies increased after mid-October and continued through the end of the year. Courtesy of MIROVA.
Figure (see Caption) Figure 133. Sentinel-2 infrared satellite imagery showed small thermal anomalies in the Minamidake crater at Aira’s Sakurajima volcano on 28 September 2022 (top left), 18 October 2022 (top right), and 27 November 2022 (bottom left). Vent A is located to the left and Vent B is to the right of Vent A; both vents are part of the Minamidake crater. Clouds covered Vent B on 28 September. A gas-and-steam emission covered the crater on 12 December 2022 (bottom right). Images use “Atmospheric penetration” rendering (bands 12, 11, and 8a). Courtesy of Sentinel Hub Playground.

JMA reported that during July there were 37 eruption events detected, 12 of which were explosion events. Accompanying eruption plumes rose 2.8 km above the crater rim. Nighttime incandescence was observed in the Minamidake crater using a high-sensitivity surveillance camera. No eruptions in the Showa crater were reported. Seismicity consisted of 146 volcanic earthquakes, which had increased compared to 57 earthquakes in June. According to field surveys, daily sulfur dioxide emissions ranged 1,400-3,200 tons/day (t/d). The Kagoshima Local Meteorological Observatory reported a total of 28 g/m2 of ashfall was observed during 6 days. On 17 July an explosion at 1852 generated an eruption plume that rose 2.8 km above the crater rim and large volcanic blocks were ejected 800-1,100 m above the crater rim (figure 134).

Figure (see Caption) Figure 134. Webcam image of the explosions at the Minamidake summit crater of Aira’s Sakurajima at 1855 on 17 July 2022. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, July 2022).

JMA reported an inflation event was first detected around 0900 on 18 July and warned residents that an inflation event suggested a magmatic intrusion was occurring. A field visit reported that sulfur dioxide emissions were at 1,900 t/d. Four eruptive events were recorded between 23 July and 1500 on 24 July that produced plumes that rose 1.2 km above the crater rim. A larger explosion at 2005 on 24 July ejected large volcanic blocks 2.4-2.5 km E. The accompanying volcanic plume rose 300 m above the crater rim and mixed with meteoric clouds. The last time an explosion ejected material more than 2 km from the crater was on 4 June 2020, according to JMA. The Volcano Alert Level (VAL) was briefly raised from 3 to 5 (on a 5-level scale) at 2050, signaling that the residents should evacuate. Ashfall was reported in Kagoshima City (10 km W). JMA noted that inflation stopped after this event. A field survey was conducted by the Japan Meteorological Agency Mobile Survey Team (JMA-MOT) on 25 July and confirmed that material was deposited more than 2.4 km from the vent, and they observed ashfall in an area from Shirahamacho (42 km NW) to Kurokamicho (5 km SE). Ash was deposited on the E flank of the Minamidake crater, based on data from infrared thermal imaging equipment and visual observations (figure 135). During 25-26 July a few small explosions and eruptive events generated plumes that rose as high as 2.2 km above the crater rim and disappeared into meteoric clouds. After 26 July, JMA noted that material had not been ejected more than 2 km from the crater, so the VAL was lowered back to 3.

Figure (see Caption) Figure 135. Photo of ashfall in Kurokamicho taken on 25 July 2022 after the explosion at Aira’s Sakurajima on 24 July 2022. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, July 2022).

There were 71 eruptions reported during August, 16 of which were explosions. Volcanic plumes rose 2.8 km above the crater rim. Nighttime crater incandescence was observed at the Minamidake crater. There were 207 volcanic earthquakes detected during the month. According to a field survey the amount of sulfur dioxide emissions released ranged between 1,500-2,500 t/d. Ashfall was not observed. On 2 August at 0055 a volcanic plume rose 2.8 km above the crater. On 15 August at 0009 an explosion produced an eruption plume that rose 2 km above the crater rim and ejected large blocks 1.3-1.7 km above the summit.

During September there were 36 eruption events and 23 of which were explosions. Volcanic plumes rose 2.8 km above the crater rim and nighttime crater incandescence persisted. There were 319 volcanic earthquakes detected during the month. Sulfur dioxide emissions ranged between 1,900-2,400 t/d. According to the Kagoshima Local Meteorological Observatory, a total of 53 g/m2 ashfall was observed over 14 days. On 23 September at 1335 a volcanic plume rose 1.7 km above the crater rim and continued until 1600. Some ashfall was observed on the SE flank. On 30 September at 1144 an explosion rose 2.8 km above the crater rim and drifted down-flank to the SE until 1600. A large amount of ash was deposited on the SE flank. Around 0000 volcanic blocks were ejected 1.3-1.7 km from the Minamidake crater.

Eruptive activity continued during October, with 39 events reported, which included 12 explosions. Volcanic plumes rose 2.4 km above the crater rim. Nighttime crater incandescence continued. Seismicity consisted of 145 volcanic earthquakes. According to a field survey, the amount of sulfur dioxide released during the month ranged from 1,900 t/d to 4,000 t/d, the latter of which was measured on 14 October. JMA noted that the amount of volcanic gas released has been generally high since July. Ashfall measurements showed that a total of 24 g/m2 fell over 18 days at the Kagoshima Local Meteorological Observatory. An explosion was detected at 1932 on 10 October that ejected material 1.3-1.7 km from the Minamidake summit crater. A field survey conducted on 11 October confirmed weak incandescence was visible in the Minamidake crater and a geothermal area was observed on the SE flank of Minamidake, part of the inner Showa crater wall. At 1424 on 18 October an eruption plume rose 2.4 km above the crater (figure 136). Smaller eruptive events were occasionally recorded during 28-31 October.

Figure (see Caption) Figure 136. Webcam image showing an eruption plume rising 2.4 km above Aira’s Sakurajima at 1429 on 18 October 2022. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, October 2022).

JMA reported 17 eruptive events occurred during November, which included 5 explosions. Volcanic plumes rose 2.2 km above the crater rim. Nighttime crater incandescence was reported in the Minamidake crater. There were 135 volcanic earthquakes detected throughout the month. The amount of sulfur dioxide emissions ranged from 700 t/d to 1,900 t/d and a total amount of 9 g/m2 of ashfall was observed at the Kagoshima Local Meteorological Observatory over 10 days. Explosions were detected at 0515 on 4 November and 1954 on 20 November and ejected volcanic blocks 600-900 m. An explosion at 2010 on 15 November generated a volcanic plume that rose 600 m above the crater rim and drifted SE. An explosion at 1334 on 21 November generated an eruption plume that rose 2.2 km above the crater rim and ejected large blocks as far as 500 m from the vent (figure 137). Small eruptive events were also detected during 25-28 November.

Figure (see Caption) Figure 137. Webcam image of an explosion at Aira’s Sakurajima on 1336 on 21 November 2022. The accompanying volcanic plume rose 2.2 km above the crater rim. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, November 2022).

During December, JMA reported that there were 20 eruptions, 11 of which were explosions. Volcanic plumes rose as high as 3.2 km above the crater rim. Nighttime crater incandescence remained visible at the Minamidake crater. There were 78 volcanic earthquakes detected during the month. According to a field survey the amount of sulfur dioxide emissions released was 1,400-2,800 t/d. During the month, 12 g/m2 of ash fell over 8 days during the month, as observed at the Kagoshima Local Meteorological Observatory. At 0340 on 2 December a volcanic plume rose 3.2 km above the crater rim and ejected blocks as far as 1.1 km from the vent (figure 138). A second explosions was detected at 1929 on 3 December that produced an eruption plume that rose 3 km above the crater rim and ejected volcanic blocks 1-1.3 km from the crater. Webcam video of the event showed incandescent material ejected above the crater and lightning in the ash plume. Two explosions were recorded on 14 December that generated eruption plumes rising 1.7 km above the crater rim and disappearing into the meteoric clouds. Ejected blocks traveled as far as 700 m from the vent. An explosion at 0805 on 17 December produced a plume that rose 700 m above the crater rim and interacted with meteoric clouds. Ejected blocks traveled 900 m from the vent. At 0449 on 22 December ejected blocks traveled 600-900 m from the vent. On 24 December at 1954 an explosion produced an eruption plume that rose 1.2 km above the crater rim and ejected large blocks as far as 1.1 km from the vent. Two explosions on 27 and 29 December generated volcanic plumes 1.7 km above the crater rim and ejected blocks as far as 900 m from the vent.

Figure (see Caption) Figure 138. Webcam image showing the explosion in the Minamidake summit crater at Aira’s Sakurajima at 0344 on 2 December 2022. The plume rose 3.2 km above the crater rim. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, December 2022).

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).

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2002: July


6 March-12 March 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 4-11 March with nighttime crater incandescence. Very small eruptive events occasionally occurred during 4-8 March. An explosion at 0359 on 9 March produced an ash plume that rose 800 m above the crater rim and drifted SE, and ejected large blocks 1.3-1.7 km from the vent. Eruptive events at 1540 on 10 March and at 0532 on 11 March generated ash plumes that rose 1.2-1.3 km above the crater rim and drifted E. An ash plume from an explosion at 2132 on 11 March rose 1.4 km above the crater rim and drifted NE; large blocks were ejected 500-700 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


28 February-5 March 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 27 February-4 March with nighttime crater incandescence. Eruptive events at 0202 on 27 February and at 1429 on 2 March generated ash plumes that rose 1 km above the crater rim and drifted E and rose 1.3 km above the crater rim and drifted SE, respectively. An explosion at 2149 on 2 March produced an ash plume that rose 1 km and drifted S and ejected large blocks 300-500 m from the vent. An explosion at 2026 on 3 March produced an ash plume that rose 1.2 km and drifted SE and ejected large blocks 600-900 m from the vent. Sulfur dioxide emissions were extremely high, averaging 3,700 tons per day on 1 March. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


21 February-27 February 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 17-26 February with nighttime crater incandescence. Very small eruptive events were recorded during 17-23 February. An explosion at 1734 on 24 February generated an ash plume that rose 400 m above the crater rim before entering weather clouds, and ejected blocks as far as 1.2 km away from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


14 February-20 February 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 12-19 February with nighttime crater incandescence. Sulfur dioxide emissions averaged 1,400 tons per day on 20 December. An explosion at 0659 on 14 February generated an ash plume that rose 2 km above the crater rim and drifted N, and ejected blocks 300-500 m away from the vent. A larger explosion at 1833 on 14 February produced an ash plume that rose as high as 5 km above the summit that drifted E and NE and ejected large blocks as far as 1.3 km from the vent. Ash plumes had not risen that high since an explosion at 0538 on 9 August 2020. A large amount of ashfall completely covered roadways in some parts of the N part of the island based on 15 February field observations. Residents reported ashfall in Kagoshima, Aira, Kirishima, Kanoya, Soo, and parts of Miyazaki Prefecture. Eruptive events at 2220 on 16 February, and 1523, 1556, 1631, and 2359 on 17 February, generated ash plumes that rose 1-1.3 km above the summit and drifted E and SE. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


7 February-13 February 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 7–13 February with nighttime crater incandescence. An eruptive event at 0917 on 8 February produced an ash plume that rose 1.3 km above the crater. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


24 January-30 January 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 22-29 January with nighttime crater incandescence. An eruptive event at 0014 on 27 January produced an ash plume that rose 1.1 km above the crater rim and drifted S. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


17 January-23 January 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 15-22 January with nighttime crater incandescence. An explosion at 0505 on 18 January produced an ash plume that rose 800 m above the crater rim and merged into weather clouds and ejected material 300-500 m from the crater rim. A small eruptive event occurred at Showa Crater on 21 January. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


10 January-16 January 2024 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 8-15 January with incandescence at the crater observed nightly. An explosion at 1552 on 9 January produced an ash plume that rose as high as 1.2 km above the crater rim and drifted E and SE. Small eruptive events were occasionally recorded during 12-15 January. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


3 January-9 January 2024 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 1-8 January with incandescence at the crater observed nightly. Small eruptive events were occasionally recorded during the week. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


27 December-2 January 2024 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 25 December 2023-1 January 2024, with incandescence at the crater observed nightly. Small eruptive events were occasionally recorded during the week. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


20 December-26 December 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 18-25 December, with incandescence at the crater observed nightly. Small eruptive events were occasionally recorded on 18 December. Sulfur dioxide emissions were high, averaging 2,700 tons per day on 20 December. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


13 December-19 December 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 11-18 December, with incandescence at the crater observed nightly. Small eruptive events were occasionally recorded through the week. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


6 December-12 December 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 4-11 December, with incandescence at the crater observed nightly. Small eruptive events were recorded during 4-8 December. Sulfur dioxide emissions were high, averaging 2,900 tons per day on 8 December. Explosions at 1028 and 1533 on 10 December produced ash plumes that rose 1.5-1.8 km above the crater rim and drifted N. An eruptive event at 1748 on that same day produced an ash plume that rose 1.2 km and drifted N. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


29 November-5 December 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 29 November-5 December, with very small eruptions and crater incandescence observed nightly. One volcanic earthquake was recorded on 3 November, and another on 4 November. A field survey conducted on 30 November detected an extremely high SO2 rate of 4,200 tonnes per day. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


22 November-28 November 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 20-27 November, with incandescence at the crater observed nightly. Explosions at 1905 on 20 November and 0226 on 21 November produced ash plumes that rose 1.2 km above the crater rim and drifted SW. Eruptive events on 22 November produced emissions that rose 1 km and drifted N and E. During an overflight of the crater on 24 November plumes obscured views of Minamidake Crater, though observers noted no changes at the geothermal area at Showa Crater. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


15 November-21 November 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 13-20 November, with incandescence at the crater observed nightly. An explosion at 2053 on 13 November produced an ash plume that rose 400 m above the crater rim. Sulfur dioxide emissions were very high, averaging 3,000 tons per day on 13 November. An explosion at 0629 on 17 November generated an ash plume that rose as high as 1.1 km above the crater rim and drifted SE to SW and ejected large blocks 500-700 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


8 November-14 November 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 8-14 November. Sulfur dioxide emissions averaged 2,700 tons per day measured on 6 November. A total of 15 explosions were recorded during 6-10 November, and a total of 8 during 10-13 November. At 2240 on 11 November an ash plume rose as high as 1.2 km above the crater rim and drifted SE and SW, large blocks were ejected 400 m from the summit crater, and crater incandescence was observed. At 2053 on 13 November an explosion generated an ash plume that rose 400 m above the crater and drifted SW. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


1 November-7 November 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 30 October-6 November, with incandescence at the crater observed nightly. Sulfur dioxide emissions averaged 1,300 tons per day on 2 November. There was a total of 10 eruptive events recorded during 30-31 October and 1-2 November. Ash plumes rose as high as 1.8 km above the crater rim and drifted N, E, and SE. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


25 October-31 October 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 23-30 October, with incandescence at the crater observed nightly. An eruptive period was recorded during 0346-0430 on 24 October; at 0346 a notable ash plume rose as high as 3.4 km above the crater rim and drifted E and ejected large blocks 1-1.3 km from the crater rim. At 0416 an ash plume rose 2.1 km above the crater rim and drifted E. A large amount of ashfall, likely from those events, was observed in Kurokami Town during a field survey later that day. Sulfur dioxide emissions were high on 25 October, averaging 2,200 tons per day. During an aerial observation on 25 October scientists noted that the N side of Showa Crater had slightly enlarged compared to the previous observations on 8 March. A high-temperature geothermal area on the Minamidake Crater floor was also visible. Periods of inflation were recorded in deformation data during 0000-1400 on 26 October and 0100-1600 on 28 October. An eruptive event at 0116 on 30 October produced an ash plume that rose 1 km above the crater rim and drifted N. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


18 October-24 October 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 16-23 October, with incandescence at the crater observed nightly. Sulfur dioxide emissions were extremely high, averaging 4,200 tons per day on 16 October. During the week, there were a total of 11 eruptive events and 20 explosions, with a daily average of 1-5 explosions recorded during 16-21 October. Ash plumes rose as high as 3.6 km above the crater rim and drifted E, SE, and S, and large blocks were ejected as far as 1.2 km from the crater rim. A period of inflation began at around 0600 on 21 October, but ceased following an eruptive event during 0346-0430 on 24 October; the event produced an ash plume that rose 2.3 km above the crater rim and ejected large blocks 1.2 km. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


11 October-17 October 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 9-16 October, with incandescence at the crater observed nightly. During the week there were a total of 18 eruptive events and 18 explosions. Ash plumes rose as high as 2.6 km above the crater rim and large blocks were ejected 800-900 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


4 October-10 October 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 2-9 October, with incandescence at the crater observed nightly. An explosion at 2228 on 4 October produced an ash plume that rose as high as 1.5 km above the crater rim and drifted S and ejected large blocks 600-900 m from the crater. A very small eruptive event was recorded during 6-9 October. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


27 September-3 October 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 25 September-2 October and incandescence at the crater was observed nightly. Very small eruptive events were recorded during the week. Sulfur dioxide emissions were high, averaging 2,300 tons per day on 25 September. The geothermal areas on the SE flank of Minamidake and near the Showa Crater were observed during a field survey on 27 September. A very small eruptive event occurred at Showa on 28 September. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


20 September-26 September 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 18-25 September and incandescence at the crater was observed nightly. Very small eruptive events were recorded during the week. Sulfur dioxide emissions averaged 1,800 tons per day on 19 September. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


13 September-19 September 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 11-18 September and incandescence at the crater was observed nightly. Sulfur dioxide emissions averaged 1,900 tons per day on 11 September. An explosion at 0018 on 11 September produced an ash plume that rose 1.1 km above the crater rim and ejected large blocks 300-500 m from the crater. An eruptive event at 1642 produced an ash plume that rose 1.3 km. At 2211 on 13 September an explosion produced an ash plume that rose 1.7 km and drifted N and ejected large blocks 500-700 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


6 September-12 September 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 4-11 September. Incandescence at Minamidake was observed nightly. Very small eruptive events occurred at both craters on 4 September. Sulfur dioxide emissions were slightly high at 1,600 tons per day on that same day. An explosion on 1512 on 9 September produced an ash plume that rose 800 m above the crater rim and ejected large blocks 500-700 m from the crater. Another explosion at 0018 on 11 September generated an ash plume that rose 1.1 km and ejected large blocks 300-500 m; an ash plume rose 1.3 km from an explosion at 1642 on that same day. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


30 August-5 September 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 28 August-4 September. Incandescence at Minamidake was observed nightly. An explosion at 0640 on 31 August from the same crater ejected large blocks 400 m away and likely produced a plume that was obscured by weather clouds. Very small eruptive events continued to be detected during the rest of the week. A very small eruption at Showa Crater was also recorded on 4 September. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


23 August-29 August 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 21-28 August. Very small eruptive events occasionally occurred at Minamidake and incandescence was observed at night. On 24 August sulfur dioxide emissions were extremely high at 3,300 tons per day. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


16 August-22 August 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 14-21 August. Very small eruptive events occasionally occurred at Minamidake and nighttime incandescence was observed at that same crater. A very small eruptive event was recorded at Showa on 17 August. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


9 August-15 August 2023 Citation IconCite this Report

JMA reported ongoing activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 7-14 August. Flashes of incandescence at Minamidake were observed during the night on 7 August. An explosion at 0345 on 9 August ejected large blocks as far as 600 m from the vent and possibly produced an ash plume, though weather conditions prevented visual confirmation. An explosion at 2205 on 13 August produced an ash plume that rose 2 km above the crater rim and drifted W. Large blocks were ejected 300-500 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


2 August-8 August 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 31 July-7 August. Nighttime incandescence at Minamidake was occasionally observed. Sulfur dioxide emissions measured during a field visit on 3 August averaged 1,800 tons per day. An eruptive event at Showa at 0542 on 4 August produced an ash plume that rose 1 km above the crater rim and drifted N, and ejected blocks 400 m from the crater. An explosion at the same crater at 2150 produced an ash plume that rose 2.3 km above the crater rim and drifted NW, and ejected blocks as far as 800 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


26 July-1 August 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 24-31 July. A very small eruption was reported on 24 July at Minamidake accompanied by occasional summit crater incandescence. An eruptive event at Showa at 0349 on 25 July produced an ash plume that rose 1 km above the crater rim and ejected blocks traveled up to 200 m from the vent. No incandescence was observed at this crater. Sulfur dioxide emissions averaged 1,600 tons per day on 26 July. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


19 July-25 July 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 16-24 July. Very small eruptive events occasionally occurred at Minamidake and incandescence was observed at night. An eruptive event at Showa on 16 July produced an ash plume that rose 1.2 km above the crater rim and drifted N. An explosion at the same crater at 2314 produced an ash plume that rose 1.8 km above the crater rim and drifted N, and also ejected blocks 300-500 m from the vent. Explosions at 1224 and 1232 on 17 July generated ash plumes that rose 2-2.5 km and drifted N, with blocks ejected 500-800 m from the vent. At 2044 on 17 July an ash plume from an explosion rose 1.2 km and drifted N. Sulfur dioxide emissions were very high, averaging 3,200 tons per day on 20 July. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


21 June-27 June 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 19-26 June. Very small eruptive events occasionally occurred at Minamidake and incandescence was observed at night. An explosion at Showa at 0438 on 22 June produced an ash plume that rose 600 m above the crater rim and drifted E and ejected blocks 500-800 m from the vent. Sulfur dioxide emissions averaged 1,400 tons per day on 22 June. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


14 June-20 June 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 13-19 June. Ash plumes from Showa were recorded at 1412 on 16 June that rose 1.3 km above the rim and drifted S, with another at 0710 on 17 June that rose up to 1 km and drifted E. Crater incandescence was observed at Minamidake crater during the night of 18 June. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


7 June-13 June 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 5-12 June. Eruptive events at Showa were recorded at 0211, 0352, 0440, and 1436 on 5 June and generated ash plumes that rose as high as 1.5 km above the crater rim and sometimes drifted E and SE. Explosions at Minamidake produced ash plumes that rose 1.5 and 2.5 km above the crater rim at 0012 on 5 June and 1401 on 7 June, respectively, and ejected blocks 500-700 m from the vent. Ash-and-gas emissions were continuous with plumes rising as high as 1.5 km and then declining to 800 m during 1401-1505 on 7 June, and drifting SE. Since the volcano is so active, JMA noted that only emissions above a certain threshold of density and height get reported; at 1505 the emission characteristics declined to below that threshold. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


31 May-6 June 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 29 May-5 June. On 29 May sulfur dioxide emissions were high at 2,900 tons per day. Crater incandescence was observed nightly at both craters during 29 May-2 June, and very small eruptive events periodically occurred. Eruptive events at Minamidake at 0237 and 0454 on 4 June produced ash plumes that rose about 1.1 km above the crater rim. An explosion at 0012 on 5 June generated an ash plume that rose 1 km and drifted SE, and ejected blocks 500-700 m from the crater. At Showa, eruptive events at 0211, 0352, 0440, and 1436 on 5 June generated ash plumes that rose 1.3-1.5 km above the crater rim and drifted SE and E, or rose straight up; blocks were ejected as far as 300 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


24 May-30 May 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 22-29 May. Crater incandescence was observed nightly at Minamidake, and during 25-29 May at Showa; incandescence at Showa had not been visible since 5 March. The only eruptive event at Showa during this period was at 1125 on 22 May, when material was ejected 200-300 m from the crater and an ash plume rose 1.5 km above the crater rim. At 0610 on 24 May an explosion at Minamidake ejected material 300-500 m from the crater and generated an ash plume that rose 1.5 km above the crater and drifted to the SW. An eruptive event at 1327 on 25 May produced an ash plume that rose 2.3 km. On 26 May two explosions (at 0647 and 1441) and an eruptive event (1311) generated ash plumes that rose as high as 1.6 km and drifted N and S. The explosion at 1441 ejected blocks 500-700 m from the vent. An explosion at 1520 on 28 May ejected material 600-900 m from the crater and produced an ash plume that rose 2.3 km from the summit . The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


17 May-23 May 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 15-22 May. Crater incandescence was observed nightly at Minamidake Crater. At 1429 on 17 May an eruptive event at Showa Crater produced an ash plume that rose 1.2 km above the crater rim and drifted N. An explosion from Minamidake Crater at 2027 generated an ash plume that rose 400 m and ejected large blocks 600-900 m from the crater; another eruptive event at 2051 produced an ash plume that rose as high as 1 km and drifted N. An explosion at Minamidake was recorded at 1519 on 18 May. Showa Crater sent an ash plume 1.5 km high at 1125 on 22 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


10 May-16 May 2023 Citation IconCite this Report

JMA reported ongoing activity at both Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) during 8-15 May. Crater incandescence was observed nightly at Minamidake Crater. On 8 May sulfur dioxide emissions were extremely high at 3,900 tons per day. At 1315 on 9 May an explosion at Minamidake generated an ash plume that rose 1.2 km above the crater rim and drifted SW, and ejected blocks 1.1 km from the vent. Eruptive events at 1527, 1724, and 1817 on 11 May produced ash plumes that rose as high as 1.3 km and drifted NW and W. At Showa Crater eruptive events recorded at 1009, 1303, and 1401 on 8 May, at 0550, 0726, 2204, and 2321 on 11 May, at 1831 on 12 May, and at 0859 on 14 May produced ash plumes that rose as high as 1.7 km above the crater rim and drifted in multiple directions. Sulfur dioxide emissions were somewhat high on 12 May, averaging 1,800 tons per day. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


3 May-9 May 2023 Citation IconCite this Report

JMA reported that Minamidake Crater and Showa Crater (Aira Caldera’s Sakurajima volcano) remained active during 1-8 May. Crater incandescence was observed nightly at Minamidake Crater. Three explosions at Minamidake during 2-3 May produced small shock waves and ash plumes. The explosion at 0422 on 2 May generated an ash plume that rose 1.8 km above the crater rim and drifted SW, and ejected blocks 500-700 m from the vent. The explosion at 0241 on 3 May produced an ash plume that rose 800 m and ejected blocks to 500-700 m from the vent. Later that morning, at 1025, an explosion produced an ash plume that rose 500 m and drifted W. An ash plume from an eruptive event at 2337 on 7 May rose 1 km. At Showa Crater very small eruptive events were recorded during 1-5 May, and three eruptive events on 8 May produced ash plumes that rose as high as 1.2 km above the crater rim and drifted S and SW. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


26 April-2 May 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 24 April-2 May, with crater incandescence visible nightly. Very small eruptive events occasionally occurred during the week. On 28 April sulfur dioxide emissions were somewhat high at 1,800 tons per day. An explosion at 0422 on 2 May ejected large blocks 500-700 m from the crater and generated an ash plume that rose 1.8 km above the crater rim and drifted SW. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


19 April-25 April 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 17-24 April, with crater incandescence visible nightly. Two eruptive events on 17 April produced ash plumes that rose 1-1.5 km and drifted S. That same day sulfur dioxide emissions were somewhat high at 1,900 tons per day. Very small eruptive events occasionally occurred during 21-24 April. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


12 April-18 April 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 10-17 April, with crater incandescence visible nightly. Very small eruptive events occasionally occurred during 10-14 April. Two eruptive events on 17 April produced ash plumes that rose as high as 1.5 km and drifted S. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


5 April-11 April 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 3-10 April, with crater incandescence visible nightly. Very small eruptive events occasionally occurred. Sulfur dioxide emissions were high at 2,700 tons per day on 4 March. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


29 March-4 April 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera's Sakurajima volcano) during 27 March-4 April with nightly crater incandescence. Five eruptive events were recorded during 27-31 March producing plumes that rose 1.5 km above the crater rim. A few small eruptive events occasionally occurred during the rest of the week. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


22 March-28 March 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 20-27 March, with crater incandescence visible nightly. Two explosions recorded on 21 and 22 March produced ash plumes that rose 1.2 km above the crater rim and ejected large blocks 1-1.3 km from the vent. Two eruptive events during 24-27 March produced volcanic plumes that rose 1.1 km. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


15 March-21 March 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 March, with crater Incandescence visible nightly. Sulfur dioxide emissions were high at 2,100 tons per day on 13 March. On 14 March an explosion produced an ash plume that rose 1 km above the crater rim. Three eruptive events were recorded during 17-20 February, producing volcanic plumes that rose as high as 1 km. No activity or crater incandescence was detected at Showa Crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


8 March-14 March 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 6-13 March. Incandescence at Minamidake was visible nightly. Five eruptive events at Minamidake were recorded and explosions occurred on 8 and 11 March. Ash plumes rose as high as 1.7 km above the crater rim, and during 10-13 March large blocks were ejected as far as 500 m from the vent. Seven eruptive events occurred at Showa during 6-10 March, producing ash plumes that rose as high as 2.7 km above the crater rim and ejecting large blocks 800 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


1 March-7 March 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 27 February-6 March. Incandescence was visible nightly at Minamidake and during 3-6 March at Showa. Explosions at Minamidake were recorded on 28 February and 1, 3, and 4 March, and non-explosive eruptive events were occasionally recorded. Eruption plumes rose as high as 2.8 km above the Minamidake Crater rim and large blocks were ejected as far as 1.3 km from the vent. Non-explosive eruptive events were occasionally recorded at Showa during 27 February-2 March and four explosions occurred during 3-6 March. Eruption plumes rose as high as 2.7 km above the Showa rim and large blocks were ejected 500-800 m from the vent. Sulfur dioxide emissions were extremely high at 3,500 tons per day on 2 March. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


22 February-28 February 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater and Showa Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 February and incandescence at both craters was visible nightly. Very small eruptive events occurred at Showa Crater. Three explosions and three or four eruptive events were recorded at Minamidake Crater during the week. Volcanic plumes rose as high as 1.5 km above the Minamidake Crater rim and large blocks were ejected 600-900 m from the vent. During an overflight on 21 February scientists observed white plumes rising from a vent on the N inner crater wall at Showa Crater and they noted more voluminous emissions compared to the 12 October 2022 overflight. No notable changes at Minamidake Crater were observed. At 1230 on 26 February an eruptive event at Minamidake Crater produced a plume that rose 1.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from both craters.

Source: Japan Meteorological Agency (JMA)


15 February-21 February 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 13-20 February and crater incandescence was visible nightly. Five explosions and five eruptive events were recorded during the week. One of the explosions, at 1448 on 14 February, produced an ash plume that rose 2.4 km above the crater rim and ejected large blocks 1.1 km from the vent. Blocks 3 cm in diameter fell near the Arimura Lava Observatory in Arimura-cho, Kagoshima City, about 3 km SE. An explosion on 19 February produced an eruption plume that rose 1.2 km and ejected blocks that fell 1.1 km away. A very small eruptive event occurred at Showa Crater on 20 February. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


8 February-14 February 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Aira Caldera’s Sakurajima volcano during 6-12 February and nightly crater incandescence. Three eruptive events and two explosions were recorded at Minamidake Crater. The first explosion, at 1815 on 9 November, generated an ash plume that rose 2 km above the crater rim and drifted N and ejected large blocks 600-900 m from the crater rim. The second explosion, at 1007 on 11 February, produced an ash plume that rose 1.7 km and ejected large blocks 600-900 m from the crater rim. An ash plume from an eruptive event at 1323 on 12 February rose 1.7 km and drifted E.

A very small eruption at Showa Crater at 1052 on 8 February produced an ash plume that rose 800 m above the crater rim. This was the first eruption at Showa Crater since 3 April 2018. Ash plumes from events recorded at 1110 and 1425 rose as high as 1 km and drifted SE and SW, respectively, and blocks were ejected 200-300 m from the crater. Ashfall was reported in an area from Arimura-cho (4.5 km SE) to Furusato-cho (3 km S). The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


1 February-7 February 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 30 January-6 February and crater incandescence was visible nightly. Sulfur dioxide emissions were high at 2,000 tons per day on 30 January. An explosion at 1951 on 3 February produced an ash plume that rose 1.2 km above the crater rim and ejected large blocks as far as 500 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


25 January-31 January 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 23-30 January and crater incandescence was visible nightly. Two explosions were recorded on 24 January, though weather clouds prevented visual confirmation. Sulfur dioxide emissions were high at 2,800 tons per day on 26 January. An explosion at 2342 on 28 January produced an ash plume that rose 2.2 km above the crater rim and ejected large blocks as far as 700 m from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


18 January-24 January 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-23 January. Crater incandescence was visible nightly. An explosion at 1215 on 18 January produced an ash plume that rose 1.4 km above the crater rim and ejected blocks as far as 1.1 km. Sulfur dioxide emissions were high at 1,400 tons per day. An explosion at 0659 on 19 January generated an ash plume that rose 1.3 km and ejected blocks 600-900 m and an explosion at 0307 on 21 January generated an ash plume that rose 1.6 km and ejected blocks as far as 1.1 km. Occasional very small eruptive events were recorded during 21-22 January. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


11 January-17 January 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 9-16 January. Crater incandescence was visible nightly. Eruptive events at 0210 on 9 January and 1837 on 14 January produced plumes that rose 1 km above the crater rim. Sulfur dioxide emissions were high at 2,100 tons per day on 13 January. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


4 January-10 January 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 2-9 January. Crater incandescence was visible nightly. Sulfur dioxide emissions were slightly elevated at 1,000 tons per day on 4 January. One explosion on 3 January and two explosions on 8 January were recorded by the seismic network. Eruption plumes rose as high as 2.4 km above the crater rim and blocks were ejected as far as 1.1 km from the vent. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


28 December-3 January 2023 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 26 December 2022-2 January 2023. Crater incandescence was visible nightly. Sulfur dioxide emissions were slightly elevated at 1,700 tons per day on 27 December. Two explosions, on 27 and 29 December, produced ash plumes that rose as high as 1.7 km above the crater rim and ejected blocks as far as 900 m from the vent. An explosion at 1423 on 2 January produced an ash plume that rose 1.5 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


21 December-27 December 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 19-26 December. Crater incandescence was visible nightly. Sulfur dioxide emissions were slightly high at 1,500 tons per day on 19 December. An explosion at 0449 on 22 December ejected blocks 600-900 m from the vent. An explosion at 1954 on 24 December produced an ash plume that rose 1.2 km above the crater rim and ejected large blocks as far as 1.1 km from the vent. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


14 December-20 December 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 12-19 December. Crater incandescence was visible nightly. Two explosions on 14 December produced eruption plumes that rose as high as 1.7 km and disappeared into weather clouds. Blocks were ejected as far as 700 m. An explosion at 0805 on 17 December produced a plume that rose 700 m and into the clouds. Blocks were ejected 900 m. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


7 December-13 December 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 5-12 December consisting of a few eruptive events and three explosions. Crater incandescence was visible nightly. Explosions produced ash plumes that rose as high as 2.7 km above the crater rim and ejected large blocks as far as 1.1 km away. Sulfur dioxide emissions were high at 2,800 tons per day on 6 December. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


30 November-6 December 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) consisting of a few eruptive events and two explosions. Crater incandescence was visible nightly, sometimes characterized as incandescent flashes. An explosion at 0340 on 2 December produced an ash plume that rose as high as 3.2 km above the crater rim and ejected large blocks as far as 1.1 km from the vent. The second explosion, recorded at 1929 on 3 December, produced an ash plume that rose as high as 3 km and ejected large blocks 1-1.3 km away. Webcam video of the event showed incandescent material ejected above the crater and lightning in the ash plume. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Sources: Japan Meteorological Agency (JMA); Treasure Official Channel


23 November-29 November 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence during 21-28 November. Sulfur dioxide emissions were 700 tons per day on 21 November. An explosion on 21 November produced an ash plume that rose as high as 2.2 km above the crater rim and ejected large blocks as far as 500 m from the vent. Small eruptive events were recorded during 25-28 November. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


16 November-22 November 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence during 14-21 November. Sulfur dioxide emissions were slightly high on 14 November at 1,100 tons per day. Six eruptive events and four explosions (during 15-16 and 20-21 November) produced volcanic plumes that rose as high as 2.2 km above the crater rim and ejected large blocks as far as 900 m from the vent. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


9 November-15 November 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence during 9-15 November. An eruptive event at 2130 on 10 November generated an eruption plume that rose to 1 km above the crater rim. An explosion at 2010 on 15 November produced an ash plume that rose 600 m above the crater and drifted SE. Seven volcanic earthquakes were detected. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


2 November-8 November 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence during 31 October-7 November. Six eruptive events and two explosions produced volcanic plumes that rose as high as 1.3 km above the crater rim and ejected large blocks as far as 900 m from the vent. Sulfur dioxide emissions were slightly high on 1 November at 1,900 tons per day. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


26 October-1 November 2022 Citation IconCite this Report

JMA reported ongoing eruptive activity at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) and nighttime crater incandescence. Two eruptive events and one explosion were recorded during 24-28 October. Volcanic plumes rose as high as 1.2 km above the crater rim and large blocks were ejected as far as 1.3 km from the vent. Very small eruptive events were occasionally recorded during 28-31 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


19 October-25 October 2022 Citation IconCite this Report

JMA reported that four eruptive events and seven explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 17-24 October. Volcanic plumes rose as high as 2.4 km above the crater rim and large blocks were ejected as far as 1.3 km from the vent. Incandescence at the crater was visible nightly. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


12 October-18 October 2022 Citation IconCite this Report

JMA reported that 10 eruptive events and four explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 10-17 October. Volcanic plumes rose as high as 1.7 km above the crater rim and large blocks were ejected as far as 1.7 km from the vent. Incandescence at the crater was visible nightly. No notable changes at the summit were visible during an overflight on 12 October. Sulfur dioxide emissions were characterized as extremely high on 14 October at 4,000 tons per day. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


5 October-11 October 2022 Citation IconCite this Report

JMA reported that nine eruptive events and one explosion at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 3-10 October. Volcanic plumes rose as high as 1.5 km above the crater rim and large blocks were ejected 600-900 m from the vent. Incandescence at the crater was visible nightly. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


28 September-4 October 2022 Citation IconCite this Report

JMA reported that 11 eruptive events and five explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 26 September-3 October. Volcanic plumes rose as high as 2.8 km above the crater rim and large blocks were ejected as far as 1.7 km from the vent. Incandescence at the crater was visible nightly. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


21 September-27 September 2022 Citation IconCite this Report

JMA reported that six eruptive events and three explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 19-26 September. Volcanic plumes rose as high as 2.4 km above the crater rim and large blocks were ejected as far as 700 m from the vent. Incandescence at the crater was visible nightly. Sulfur dioxide emissions were somewhat high at 1,900 tons per day on 22 September. Nighttime incandescence at the crater was visible during 2-16 September. A notable eruptive event at 1335 on 23 September generated an ash plume that rose 1.7 km above the crater rim and also drifted down-flank to the SE until 1600. A large amount of ashfall was deposited on the SE flank. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


14 September-20 September 2022 Citation IconCite this Report

JMA reported that 10 explosions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 12-19 September. Volcanic plumes produced by the explosions rose as high as 1.6 km above the crater rim and ballistics were ejected as far as 1.3 km from the vent. Sulfur dioxide emissions were high at 2,400 tons per day on 14 September. Nighttime incandescence at the crater was visible during 2-16 September. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


7 September-13 September 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 5-12 September. The seismic network recorded four eruptive events and seven explosions. Volcanic plumes rose as high as 2.3 km above the crater rim and ballistics were ejected as far as 1.3 km from the vent. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


31 August-6 September 2022 Citation IconCite this Report

JMA reported low but continuing activity from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 29 August-5 September. Small eruptive events were recorded throughout the week, and crater incandescence was visible nightly. Sulfur dioxide emissions were 2,500 tons per day on 30 August, the same rate as the last measurement on 16 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


24 August-30 August 2022 Citation IconCite this Report

JMA reported low but continuing activity from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 August. Small eruptive events were recorded throughout the week, and nighttime incandescence from the crater was visible during 26-29 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


17 August-23 August 2022 Citation IconCite this Report

JMA reported that 0009 on 15 August an explosion at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 2 km above the crater rim. Sulfur dioxide emissions were slightly high at 1,500 tons per day, measured during a field visit on 16 August. Two eruptive events were recorded during 19-22 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


10 August-16 August 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 8-15 August. The seismic network recorded 33 eruptive events and 12 explosions. Volcanic plumes rose as high as 2.5 km above the crater rim and material was ejected large ballistics as high as 1.7 km above the summit. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


3 August-9 August 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 1-8 August. The seismic network recorded 25 eruptive events and seven explosions. Volcanic plumes rose as high as 2.8 km above the crater rim and material was ejected material as high as 1.3 km above the summit. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


27 July-2 August 2022 Citation IconCite this Report

JMA lowered the Alert Level for Aira Caldera’s Sakurajima volcano to 3 (on a 5-level scale) on 27 July, noting that after the larger eruption on 24 July material had not been ejected more than 2 km from the crater; residents were warned to stay 2 km away from the crater. During 25 July-1 August the seismic network recorded about 11 explosions and 19 eruptive events, producing plumes that rose as high as 2.2 km above the summit and ejected material far as 1.1 km. Crater incandescence was visible nightly. No deformation was detected.

Source: Japan Meteorological Agency (JMA)


20 July-26 July 2022 Citation IconCite this Report

A notable eruption at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) occurred on 24 July. The event was preceded by inflation first detected at around 0900 on 18 July. JMA warned residents that the inflation represented an intrusion of magma that could result in a large explosion. Sulfur dioxide emissions were at 1,900 tons per day, measured during a field visit on 22 July. Four eruptive events recorded between 23 July and 1500 on 24 July produced plumes that rose 1.2 km above the crater rim; the events did not change the rate of inflation. A larger eruptive event occurred at 2005 on 24 July that ejected bombs more than 2.4 km E, the first time material fell beyond 2 km from the crater since 4 June 2020. The event produced minor plumes that rose 300 m before mingling with weather clouds. The Alert Level was raised to 5 (the highest level on a 5-level scale) at 2050, signaling that residents should evacuate. According to a news article 51 people in 33 households living within a 3-km radius of both Minamidake and Showa craters left their homes. Ashfall was reported in Kagoshima City (about 10 km W). JMA noted that inflation ceased after the event. On 25 July JMA scientists conducted a field visit and confirmed that bombs were deposited more than 2.4 km from the vent and observed ashfall in an area from Shirahamacho to Kurokamicho. During 25-26 July a few small explosions and eruptive events generated plumes that rose as high as 2.2 km above the crater rim and disappeared into the weather clouds. Deformation had stagnated.

Sources: Japan Meteorological Agency (JMA); The Japan Times


13 July-19 July 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 11-18 July. Sulfur dioxide emissions were measured at 1,400 tons per day on 13 July. One explosion, recorded at 1852 on 17 July, produced an ash plume that rose as high as 2.8 km above the crater rim and ejected material as high as 1.1 km above the summit. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


29 June-5 July 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 28 June-4 July. Two eruptive events and one explosion produced plumes that rose as high as 1.6 km above the crater rim. An explosion, the first recorded since 28 January, was detected at 1221 on 27 June and ejected tephra 600-900 m above the crater rim. The sulfur dioxide rate was 800 tons per day on 30 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


22 June-28 June 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 20-27 June. At 1221 on 27 June an eruptive event produced an ash plume that rose 1.5 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


8 June-14 June 2022 Citation IconCite this Report

JMA reported that nighttime incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 6-13 June. Very small eruptive events were recorded during 6-10 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


25 May-31 May 2022 Citation IconCite this Report

JMA reported that a very small eruptive event was recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 23-30 May. Crater incandescence was visible at night during 23-27 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


18 May-24 May 2022 Citation IconCite this Report

JMA reported that a very small eruptive event was recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 16-23 May. Crater incandescence was visible at night. At 0900 on 17 May an eruptive event produced a plume that rose 1.5 km above the crater rim. That same day the sulfur dioxide rate was slightly high at 1,700 tons per day. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


11 May-17 May 2022 Citation IconCite this Report

JMA reported that a very small eruptive event was recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 9-13 May. An eruptive event at 1141 on 15 May generated a plume that rose 1.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


4 May-10 May 2022 Citation IconCite this Report

JMA reported that sulfur dioxide emissions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were slightly high at 500 tons per day on 2 May. At 1453 on 3 May an eruption produced a plume that rose 1.1 km above the crater rim. Very small eruptive events were recorded during 6-9 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


27 April-3 May 2022 Citation IconCite this Report

JMA reported that a very small eruptive event was recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) on 2 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


20 April-26 April 2022 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 18-25 April. Crater incandescence was periodically visible at night. The sulfur dioxide emissions were slightly high at 1,300 tons per day on 19 April but then dropped to 500 tons per day on 22 April. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


13 April-19 April 2022 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 11-18 April. Crater incandescence was periodically visible at night. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


6 April-12 April 2022 Citation IconCite this Report

JMA reported that incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 4-11 April. Very small eruptive events were recorded on 6 and 9 April. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


30 March-5 April 2022 Citation IconCite this Report

JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 29 March through 4 April. After 2 April, incandescence was observed at night with a high-sensitivity surveillance camera. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


23 March-29 March 2022 Citation IconCite this Report

JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 21-28 March. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


16 March-22 March 2022 Citation IconCite this Report

JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-21 March. Crater incandescence was visible at night. The sulfur dioxide emission rate was slightly high at 1,300 tons per day on 17 March. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


16 February-22 February 2022 Citation IconCite this Report

JMA reported that at 1540 on 15 February an eruption at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) produced plumes that rose 1.3 km above the crater rim and into weather clouds. Sulfur dioxide emissions were slightly high at 1,200 tons per day on 17 February. A very small eruptive event was recorded on 20 February. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


9 February-15 February 2022 Citation IconCite this Report

JMA reported that nighttime crater incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible during 7-11 February. Sulfur dioxide emissions were 700 tons per day, slightly low. An eruptive event at 1620 on 13 February produced a plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


2 February-8 February 2022 Citation IconCite this Report

JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 31 January-4 February. Ejected incandescent material was visible at night during 4-7 February. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


26 January-1 February 2022 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 24-31 January. Two explosions occurred on 28 January. One of them, recorded at 1319, produced an ash plume that rose 3.4 km above the crater rim and ejected blocks as high as 1.7 km. Ash fell in Arimura (4.5 km SE) and Kurokami (4 km E). JMA noted that until this event explosion plumes had not exceeded 3 km since 5 April 2021. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


19 January-25 January 2022 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 17-24 January. Sulfur dioxide emissions were somewhat high on 17 January at 1,000 tons per day. Two explosions on 18 January produced ash plumes that rose as high as 2 km above the crater rim and ejected ballistics 1-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


12 January-18 January 2022 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 10-17 January. Seismic data showed a decreasing number of volcanic earthquakes. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


5 January-11 January 2022 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 3-10 January. An eruptive event at 0143 on 7 January produced an ash plume that rose 1.3 km and ejected bombs 600-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


29 December-4 January 2022 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 27 December 2021 to 3 January 2022. An eruptive event at 2324 on 28 December produced an ash plume that rose 1.1 km above the crater rim. An eruptive event at 2105 on 1 January 2022 generated ash plumes that rose 1 km and ejected bombs 600-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


22 December-28 December 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 20-27 December. The sulfur dioxide emission rate was 600 tons per day on 20 December. Two eruptive events during 20-24 December produced plumes that rose 1.1 km above the crater rim. Very small eruptive events were detected during 24-27 December. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


15 December-21 December 2021 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were detected during 13-20 December. The sulfur dioxide emission rate was slightly high at 1,200 tons per day on 13 December. Crater incandescence was visible at night during 13-17 December. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


8 December-14 December 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 6-13 December. As many as five eruptive events generated plumes that rose 1.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


1 December-7 December 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 29 November-6 December. An eruptive event at 1702 on 2 December generated a plume that rose 1.3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


24 November-30 November 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 22-29 November. An eruptive event at 1509 on 25 November generated a plume that rose 1 km above the crater rim. The sulfur dioxide emission rate was slightly high at 1,200 tons per day on 26 November; sulfur dioxide emissions had been generally high since late September 2020. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


17 November-23 November 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 15-22 November. Three eruptive events were recorded during 15-19 November. The sulfur dioxide emission rate was 700 tons per day on 16 November. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


10 November-16 November 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 8-15 November. Very small eruptions were recorded. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


3 November-9 November 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 1-8 November. An eruption at 2225 on 2 November produced a plume that rose 1.1 km above the crater rim and drifted SW. The sulfur dioxide emission rate was 1,000 tons per day on 4 November. Very small eruptions were detected during 5-8 November. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


27 October-2 November 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 25 October-1 November. Two very small eruptions were detected on 28 and 31 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


20 October-26 October 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 18-25 October. The sulfur dioxide emission rate was 1,000 tons per day on 22 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


13 October-19 October 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 11-18 October. The sulfur dioxide emission rate was 800 tons per day on 11 October. A very small eruptive event was recorded on 14 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


6 October-12 October 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 4-11 October. The sulfur dioxide emission rate was 400 tons per day on 5 October. An explosion at 0517 on 8 October ejected material 600-900 m away from the crater and produced an eruption plume that was obscured by weather clouds. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


29 September-5 October 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 27 September-4 October. The trend of inflation that was first detected on 13 September continued. The sulfur dioxide emission rate was 1,500 tons per day on 28 September. A very small eruptive event occurred on 3 October. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


22 September-28 September 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible on most nights during 20-27 September. The trend of inflation first detected on 13 September had begun to slow down by 21 September. The sulfur dioxide emission rate was high at 2,600 tons per day on 22 September. An eruptive event at 0110 on 23 September and two more during 24-27 September produced plumes that rose 1.1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


15 September-21 September 2021 Citation IconCite this Report

JMA reported that an explosion at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) at 1617 on 19 September produced an eruption plume that rose 1 km above the crater rim. Crater incandescence was visible at night during 20-21 September. The report noted that inflation around the summit continued to be recorded. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


8 September-14 September 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 6-10 September. Deformation data showed inflation beginning at around 0300 on 13 September. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


4 August-10 August 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 2-9 August. Very small eruptive events were recorded during 2-6 August. The sulfur dioxide emission rate was relatively elevated at 1,500 tons per day on 4 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


28 July-3 August 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 26 July-2 August. An eruptive event at 2009 on 28 July produced a plume that rose 1.3 km above the crater rim. A very small eruptive event was recorded on 2 August. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


21 July-27 July 2021 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 19-26 July. A very small eruptive event was recorded on 19 July. The sulfur dioxide emission rate was relatively elevated at 1,000 tons per day on 21 July. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


7 July-13 July 2021 Citation IconCite this Report

JMA reported that very small eruptive events were occasionally recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano). Crater incandescence was visible at night during 9-12 July. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


30 June-6 July 2021 Citation IconCite this Report

JMA reported nightly incandescence during 28 June-5 July from Minamidake Crater (at Aira Caldera’s Sakurajima volcano). An eruptive event on 29 June produced an ash plume that rose 1 km before entering weather clouds. The sulfur dioxide emission rate was low at 600 tons per day on 30 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


16 June-22 June 2021 Citation IconCite this Report

JMA reported that during 14-21 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The sulfur dioxide emission rate was elevated at 1,400 tons per day on 15 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


9 June-15 June 2021 Citation IconCite this Report

JMA reported that during 7-14 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The sulfur dioxide emission rate was low at 900 tons per day on 9 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


2 June-8 June 2021 Citation IconCite this Report

JMA reported that during 31 May-7 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly and very small eruptive events were occasionally recorded. The sulfur dioxide emission rate was 2,700 tons per day on 2 June. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


26 May-1 June 2021 Citation IconCite this Report

JMA reported that during 24-31 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Very small eruptive events were occasionally recorded. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


19 May-25 May 2021 Citation IconCite this Report

JMA reported that during 21-24 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. A very small eruptive event was recorded on 23 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


12 May-18 May 2021 Citation IconCite this Report

JMA reported that during 10-17 May nightly incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible. Very small eruptive events were occasionally recorded. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


5 May-11 May 2021 Citation IconCite this Report

JMA reported that during 3-10 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There were four explosions and four non-explosive events during 3-7 May, producing ash plumes that rose as high has 2.5 km above the summit and ejecting bombs 0.8-1.1 km away from the crater. Very small eruptive events were recorded during 7-10 May. The sulfur dioxide emission rate was 1,300 tons per day on 19 May. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


28 April-4 May 2021 Citation IconCite this Report

JMA reported that during 26 April-3 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There was a total of 10 explosions, producing ash plumes that rose as high has 2.4 km above the summit and ejected bombs 1.3-1.7 km away from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


21 April-27 April 2021 Citation IconCite this Report

JMA reported that during 19-26 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There was a total of 16 explosions, producing ash plumes that rose as high as 2.3 km above the summit and ejected bombs 1-1.3 km away from the crater. The sulfur dioxide emission rate was somewhat high at 1,800 tons per day on 21 April. An explosion at 0109 on 25 April produced what was initially thought to be a pyroclastic flow, triggering JMA to warn residents beyond a 2-km radius to be cautious and vigilant. Scientists conducting field observations later that day did not observe pyroclastic flow deposits or damaged vegetation, and concluded that the plume phenomenon was generated by winds. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.

Source: Japan Meteorological Agency (JMA)


14 April-20 April 2021 Citation IconCite this Report

JMA reported that during 12-19 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There was a total of nine explosions and one eruptive event. Ash plumes rose 1-2 km above the summit and bombs were ejected 800-1,300 m away from the crater. The sulfur dioxide emission rate was high at 2,400 tons per day on 12 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 April-13 April 2021 Citation IconCite this Report

JMA reported that at 0641 on 5 April and explosion at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) produced an ash plume that rose as high as 3 km above the crater rim and ejected material 800-1,000 m away from the crater. Five explosions were recorded during 9-12 April. The highest ash plume rose 2.1 km and bombs were ejected as far as 900 m from the crater. Crater incandescence was visible nightly. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


31 March-6 April 2021 Citation IconCite this Report

JMA reported that during 29-30 March explosions at Minamidake Crater (at Aira Caldera's Sakurajima volcano) produced ash plumes that rose as high as 2.7 km above the crater rim and ejected bombs 600-900 m away. An explosion was recorded on 4 April. An explosion at 0641 on 5 April ejected bombs 800-1,100 m away from the crater and generated an ash plume that rose up to 3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 March-30 March 2021 Citation IconCite this Report

JMA reported that during 22-26 March incandescence from Minamidake Crater (at Aira Caldera's Sakurajima volcano) was visible nightly. An explosion on 25 March produced an eruption plume that rose 1.4 km above the crater rim. On 27 March at 0236 an eruption generated an ash plume that rose 2.5-4 km above the crater rim and drifted NW, resulting in a large amount of ashfall in Kagoshima City (about 10 km W). Volcanic bombs were ejected 1-1.3 km away from the crater. An eruption on 29 March at 1557 produced an eruption plume that rose 2.2 km above the crater rim and drifted SE, resulting in a pyroclastic flow down the SE flank and ashfall in Kagoshima City and the Kagoshima Prefecture. An explosion on 30 March at 0433 generated an ash plume that rose 2.7 km above the crater and drifted E, ejecting bombs 600-900 m from the crater. Ashfall was again reported in Kagoshima City. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 March-23 March 2021 Citation IconCite this Report

JMA reported that during 15-22 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. An explosion on 15 March produced an eruption plume that rose 1.5 km above the crater rim and ejected bombs 500-700 m away from the crater. The explosions on 20 March generated plumes that rose as high as 1.6 km. The sulfur dioxide emission rate was 1,800 tons per day on 12 March. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 March-16 March 2021 Citation IconCite this Report

JMA reported that during 8-15 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Seven explosions and 10 non-explosive events generated eruption plumes that rose 2.4-2.7 km above the crater rim and ejected bombs 0.8-1.7 km away from the crater. The sulfur dioxide emission rate was 2,300 tons per day on 10 March. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 March-9 March 2021 Citation IconCite this Report

JMA reported that during 1-8 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. An explosion at 1810 on 1 March ejected bombs 600-900 m away from the crater; an eruption plume was not confirmed. That same day the sulfur dioxide emission rate was high, at 2,900 tons per day. An explosion on 5 March produced an eruption plume that rose 2.7 km above the summit and ejected bombs 800-1,100 m away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 February-2 March 2021 Citation IconCite this Report

JMA reported that during 22 February-1 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Three explosions and four non-explosive events generated eruption plumes that rose as high as 2.6 km above the crater rim and ejected bombs 0.6-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 February-23 February 2021 Citation IconCite this Report

JMA reported that during 15-22 February incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. An explosion on 16 February generated an eruption plume that rose 1 km above the crater rim and ejected bombs 1-1.3 km away from the crater. That same day the sulfur dioxide emission rate was extremely high, at 4,300 tons per day. An ash plume from an explosion at 2253 on 21 February rose 1.6 km and entered weather clouds. Large bombs were ejected 800-1,100 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 February-16 February 2021 Citation IconCite this Report

JMA reported that during 8-15 February incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. One explosion and five eruptive events generated eruption plumes that rose 1.4-1.5 km above the crater rim and ejected bombs 800-1,100 km away from the crater. The sulfur dioxide emission rate was high, at 2,500 tons per day on 9 February. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 February-9 February 2021 Citation IconCite this Report

JMA reported that during 29 January-1 February incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. Seven explosions generated eruption plumes that rose as high as 2 km above the crater rim and ejected bombs 1,000-1,300 km away from the crater. The sulfur dioxide emission rate was 1,100 tons per day on 2 February. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 January-2 February 2021 Citation IconCite this Report

JMA reported that during 25 January-1 February incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible at night. Ten explosions generated eruption plumes that rose 1.8-2.3 km above the crater rim and ejected bombs 800-1,100 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 January-26 January 2021 Citation IconCite this Report

JMA reported that during 18-25 January incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. The sulfur dioxide emission rate slightly high, reaching 1,500 tons per day on 18 January. Two explosions, on 18 and 20 January, produced eruption plumes that rose 1.3-1.7 km above the crater rim and ejecting bombs 1.3-1.7 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 January-19 January 2021 Citation IconCite this Report

JMA reported that during 11-18 January incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. The sulfur dioxide emission rate remained high, reaching 2,100 tons per day on 13 January. Five explosions and three eruptive events were recorded, producing eruption plumes that rose 1.3-2 km above the crater rim and ejecting bombs 500-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 January-12 January 2021 Citation IconCite this Report

JMA reported that during 4-11 January incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. The sulfur dioxide emission rate remained high and reached extremely high levels of 5,000 tons per day on 6 January. An explosion at 1642 on 4 January produced an ash plume that rose 1.8 km above the crater rim and merged into weather clouds. An explosion at 1133 on 11 January generated an ash plume that rose 1.3 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 December-5 January 2021 Citation IconCite this Report

JMA reported that during 28 December-4 January incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. The sulfur dioxide emission rate remained high. Four explosions were recorded during 28 December-1 January; an explosion at 1614 on 29 December generated ash plumes that rose as high as 3.5 km above the crater rim and ejecting bombs 1.3-1.7 km away from the crater. Very small eruptive events were recorded during 2-4 January. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 December-29 December 2020 Citation IconCite this Report

JMA reported that during 21-28 December incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. The sulfur dioxide emission rate remained high, with 2,900 tons measured on 21 December. Six explosions were recorded, generating plumes that rose as high as 2.4 km above the crater rim and ejected bombs 0.6-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 December-22 December 2020 Citation IconCite this Report

JMA reported nightly incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-21 December and that the sulfur dioxide emission rate remained high. Four explosions were recorded during 16-18 December. One of the explosions, at 1959 on 17 December, generated a plume that rose 3 km above the crater rim and ejected bombs 1.3-1.7 km away from the crater. Another explosion, at 0439 on 18 December, produced a plume that rose 1.8 km and ejected bombs 1-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


9 December-15 December 2020 Citation IconCite this Report

JMA reported that during 7-14 December incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly and the sulfur dioxide emission rate remained high. Three explosions during 7-11 December produced ash plumes that rose as high as 2.4 km above the crater rim and ejected bombs 1.3-1.7 km away from the crater. An eruptive event at 0514 on 14 December produced a plume that rose 1.8 km and blended into weather clouds. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


2 December-8 December 2020 Citation IconCite this Report

JMA reported that during 30 November-7 December incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was often visible nightly. An explosion on 2 December produced an eruption plume that rose 1 km above the crater rim and blended into weather clouds. Volcanic bombs were ejected 1-1.3 km away from the crater. That same day the sulfur dioxide emission rate was high, at 2,500 tons per day. During 4-7 December two eruption plumes rose as high as 1.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 November-1 December 2020 Citation IconCite this Report

JMA reported that during 23-30 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Very small eruptive events were recorded. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 November-24 November 2020 Citation IconCite this Report

JMA reported that during 16-23 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. One explosion and two eruptive events produced plumes that rose 1.4-1.6 km above the crater rim. The daily sulfur dioxide emission rate was high at 2,000 tons per day on 18 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 November-17 November 2020 Citation IconCite this Report

JMA reported that during 9-16 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Two explosions on 10 November produced ash plumes that rose as high as 1.6 km above the crater rim and ejected bombs 600-900 m away from the crater. An eruptive event at 0708 on 16 November generated a plume that rose 1.3 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 November-10 November 2020 Citation IconCite this Report

JMA reported that during 2-9 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Two explosions during 1-2 November produced ash plumes that rose as high as 1.8 km above the crater rim. An explosion was recorded at 1504 on 7 November but the weather conditions prevented visual conformation. The daily sulfur dioxide emission rate was high at 2,200 tons per day on 9 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 October-3 November 2020 Citation IconCite this Report

JMA reported that during 26 October-2 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. An eruption at 0620 on 30 October produced a plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 October-20 October 2020 Citation IconCite this Report

JMA reported that during 14-20 October incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. A small eruption was recorded on 13 October. During an overflight that same day scientists observed lava at the bottom of the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 October-13 October 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 5-12 October. Crater incandescence was visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 September-6 October 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 29 September-3 October. Crater incandescence was visible at night. An eruptive event at 1635 on 3 October produced a plume that rose 1.7 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 September-29 September 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 14-21 September. Crater incandescence was visible at night. The daily sulfur dioxide emission rate was high at 2,000 tons per day on 25 September. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 September-22 September 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 14-21 September. Crater incandescence was visible at night. An eruption at 0810 on 15 September generated an ash plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 September-14 September 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were occasionally recorded during 7-14 September. Nighttime crater incandescence was noted during 9-10 and 12-13 September. The daily sulfur dioxide emission rate was elevated at 1,300 tons/day on 11 September. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


2 September-8 September 2020 Citation IconCite this Report

JMA reported that 12 eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 31 August-7 September produced plumes that rose as high as 1.7 km above the crater rim. The daily sulfur dioxide emission rate was 1,400 tons/day on 31 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 August-1 September 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 17-28 August; the volcano was quiet during 29-31 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 August-18 August 2020 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were recorded during 10-17 August. The daily sulfur dioxide emission rate was just over 1,000 tons/day on 13 August. During an overflight on 14 August observers noted that emissions were rising from multiple vents in the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 August-11 August 2020 Citation IconCite this Report

JMA reported that the daily sulfur dioxide emission rate at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was 700 tons/day on 3 August. An explosion at 0538 on 9 August produced an ash plume that rose as high as 5 km above the crater rim; ejected blocks were not visually confirmed due to weather conditions. Ashfall was reported in areas N of the crater including Kagoshima City (about 10 km W), Kirishima City (20 km NE), Yusui Town (40 km N), and parts of the Miyazaki Prefecture and the Kumamoto Prefecture. After the explosion at 0538, smaller eruptions were intermittently detected through 10 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 July-14 July 2020 Citation IconCite this Report

JMA reported very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 6-10 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 July-7 July 2020 Citation IconCite this Report

JMA reported very small eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 29 June-3 July; inclement weather prevented visual observations during 4-6 July. The sulfur dioxide emission rate was 1,300 tons per day on 2 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 June-30 June 2020 Citation IconCite this Report

JMA reported that during 22-26 June two eruptive events at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) produced plumes that rose as high as 1,300 m above the crater rim. An explosion at 1807 on 28 June ejected material 1,000-1,300 m away from the crater and produced a plume that rose 600 m above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 June-23 June 2020 Citation IconCite this Report

JMA reported that very small eruptive events were recorded at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 19-22 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 June-16 June 2020 Citation IconCite this Report

JMA reported that there were four explosive events and one eruptive event at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 8-12 June. An explosion at 1119 on 10 June produced a plume that rose 3.2 km above the crater rim and ejected large rocks 1.3-1.7 km away from the crater. Sulfur dioxide emissions remained high. No observable activity was recorded during 13-15 June, though inclement weather obscured views. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 June-9 June 2020 Citation IconCite this Report

JMA reported that during 1-8 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was sometimes visible at night. An explosion at 0259 on 4 June produced a plume that rose 1.5 km above the crater rim and ejected material almost 2 km away from the crater. Vibrations from the explosion were detected at the Seto Observatory, 4 km from the crater. During field surveys on 4 and 8 June deposits of tephra (up to 5 cm in diameter) were observed in areas 4-5 km E, and large blocks had fallen 3 km SW; craters created from the impact of the blocks were about 6 m in dimeter and 2 m deep. An explosion at 0130 on 5 June generated a plume that rose 3.7 km above the rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 May-2 June 2020 Citation IconCite this Report

JMA reported that during 25 May-1 June incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible almost nightly. The daily sulfur dioxide emission rate was high. There were three explosive events and 18 eruptive events during 25-29 May with plumes rising as high as 3 km above the crater rim. Material was ejected 800-1,100 m away from the crater. An eruption at 1337 on 1 June generated an ash plume that rose to 3 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 May-26 May 2020 Citation IconCite this Report

JMA reported that during 18-25 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There were 17 explosive events and five eruptive events with plumes rising as high as 2.8 km above the crater rim. Material was ejected 800-1,300 m away from the crater. The daily sulfur dioxide emission rate was high; it was just over 1,200 tons per day on 22 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 May-19 May 2020 Citation IconCite this Report

JMA reported that during 11-18 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There were 10 explosive events with plumes rising as high as 2 km above the crater rim. Material was ejected 600-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 May-12 May 2020 Citation IconCite this Report

JMA reported that during 4-11 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. There were four eruptive events with plumes rising as high as 2.3 km above the crater rim. Three explosions were recorded; an explosion at 0531 on 9 May produced an ash plume that rose 4.2 km and ejected material 600-900 m away from the crater. JMA noted that ash plumes had not risen higher than 4 km since 8 November 2019. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 April-5 May 2020 Citation IconCite this Report

JMA reported that during 27 April-4 May incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. An explosion at 2246 on 27 April generated an ash plume that rose over 3 km above the crater rim and ejected blocks 600-900 m from the crater. An eruptive event at 1510 on 2 May produced a plume that rose 1.4 km above the rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 April-28 April 2020 Citation IconCite this Report

JMA reported that during 20-27 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The seismic network recorded 11 eruptive events and five explosions. Ash plumes rose as high as 2.5 km above the crater rim and blocks were ejected as far as 1.1 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 April-21 April 2020 Citation IconCite this Report

JMA reported that during 13-20 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The seismic network occasionally recorded very small eruptive events and three explosions. Ash plumes rose as high as 2.5 km above the crater rim. The sulfur dioxide emission rate was high at 1,700 and 2,000 tons/day on 14 and 17 April, respectively. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 April-14 April 2020 Citation IconCite this Report

JMA reported that during 6-13 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The seismic network recorded 16 eruptive events and 6 explosions. Ash plumes rose as high as 2 km above the crater rim and material was ejected 300-500 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 April-7 April 2020 Citation IconCite this Report

JMA reported that during 30 March-6 April incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. The seismic network recorded 22 eruptive events and one explosion (at 1558 on 4 April). The highest plume during the period rose to 3.8 km above the crater rim, visible at 1621 on 4 April. Material was ejected 500-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 March-31 March 2020 Citation IconCite this Report

JMA reported that during 23-30 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Twelve eruptive events were recorded along with three explosions during 23-27 March. An eruption at 1041 on 27 March produced an ash plume that rose 1.8 km above the crater rim and ejcted material 800-1,100 m away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 March-24 March 2020 Citation IconCite this Report

JMA reported that during 16-23 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Occasional eruptive events were recorded along with seven explosions. Ash plumes rose 2.8-3 km above the crater rim and material was ejected 1.1-1.7 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 March-17 March 2020 Citation IconCite this Report

JMA reported that during 9-16 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Occasional eruptive events were recorded. An eruption at 1433 on 12 March generated an ash plume that rose 2.1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 March-10 March 2020 Citation IconCite this Report

JMA reported that during 2-9 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Occasional eruptive events were recorded. An eruption at 0457 on 7 March generated an ash plume that rose 1.3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 February-3 March 2020 Citation IconCite this Report

JMA reported that during 25 February-2 March there were six explosions and three non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 2.6 km above the crater rim and material was ejected 600-1,300 m away from the crater. Crater incandescence was visible every night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


19 February-25 February 2020 Citation IconCite this Report

JMA reported that during 17-25 February there were 34 explosions and 19 non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 2.4 km above the crater rim and material was ejected 600-1,100 m away from the crater. Crater incandescence was visible every night. The sulfur dioxide emission rate was elevated at 1,900 tons/day on 20 February. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 February-18 February 2020 Citation IconCite this Report

JMA reported that during 10-17 February there were 13 explosions and seven non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 1.4 km above the crater rim and material was ejected 600-900 m away from the crater. Crater incandescence was visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 February-11 February 2020 Citation IconCite this Report

JMA reported that during 3-7 February there were 16 explosions and 21 non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 2.2 km above the crater rim and material was ejected 1,000-1,300 m away from the crater. Crater incandescence was visible at night. An explosion at 0126 on 10 February produced an ash plume that rose 1.4 km and ejected material as far as 1.8 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 January-4 February 2020 Citation IconCite this Report

JMA reported that during 27 January-3 February there were 26 explosions and 33 non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 2.2 km above the crater rim and material was ejected 700-1,300 m away from the crater. Crater incandescence was visible at night. The sulfur dioxide emission rate was very high at 4,700 tons/day on 31 January. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 January-28 January 2020 Citation IconCite this Report

JMA reported that during 20-27 January there were 27 explosions and nine non-explosive eruptive events detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 2.2 km above the crater rim and material was ejected 1-1.7 km away from the crater. Crater incandescence was visible at night. The sulfur dioxide emission rate was very high at 4,400 tons/day on 20 January. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 January-21 January 2020 Citation IconCite this Report

JMA reported nighttime crater incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-20 January. Small eruptive events were occasionally recorded by the seismic network. A total of 21 explosions were detected, with ash plumes rising as high as 2 km above the crater rim and large blocks ejected as far as 1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 January-14 January 2020 Citation IconCite this Report

JMA reported nighttime crater incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 6-14 January. Small eruptive events were occasionally recorded by the seismic network. Explosions were recorded during 6, 10, and 12-14 January; ash plumes rose 1.8-2.3 km above the crater rim and material was ejected as far as 1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 January-7 January 2020 Citation IconCite this Report

JMA reported nighttime crater incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 30 December-6 January. Small eruptive events were occasionally recorded by the seismic network. An explosion on 6 January produced an ash plume that rose 1.7 km above the crater rim and ejected material as far as 1.1 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 December-31 December 2019 Citation IconCite this Report

JMA reported that during 23-27 December there were three explosions and one non-explosive eruptive event detected by the Minamidake Crater (at Aira Caldera’s Sakurajima volcano) seismic network. Ash plumes rose as high as 3.3 km above the crater rim and material was ejected 600-900 m away from the crater. Crater incandescence was visible at night and minor eruptive activity continued during 27-30 December. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 December-24 December 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 16-23 December. There were 16 explosions and nine non-explosive eruptive events detected by the seismic network. Ash plumes rose as high as 2.5 km above the crater rim and material was ejected 0.5-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 December-17 December 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 9-16 December. There were 15 explosions and 10 non-explosive eruptive events detected by the seismic network. Ash plumes rose 2.4 km above the crater rim, although explosions at 0115 and 2109 on 10 December generated ash plumes that rose 3 km above the crater rim. Blocks were ejected as far as 1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 December-10 December 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 2-9 December. There were 15 explosions and four non-explosive eruptive events detected by the seismic network. Ash plumes rose 2.3-2.6 km above the crater rim and blocks were ejected as far as 1.7 km away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 November-3 December 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 25 November-2 December. There were 16 explosions and three non-explosive eruptive events detected by the seismic network. Ash plumes rose as high as 2.7 km above the crater rim and blocks were ejected as far as 1.3 km away. One of the explosions, recorded at 2010 on 28 November, produced an eruption plume that rose 3.3 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 November-26 November 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 18-25 November. There were 17 explosions and four non-explosive eruptive events detected by the seismic network. Ash plumes rose as high as 2.7 km above the crater rim and blocks were ejected as far as 1.7 km away. The sulfur dioxide emission rate was 2,800 tons/day on 21 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 November-19 November 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 11-18 November. There were 27 explosions and 29 non-explosive eruptive events detected by the seismic network. Ash plumes rose as high as 2.5 km above the crater rim and blocks were ejected 600-900 m away. An explosion at 0200 on 13 November generated an ash plume that rose 3.6 km and ejected large blocks that fell 1.7 km away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 November-12 November 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 5-11 November. There were 13 explosions and 25 non-explosive eruptive events detected by the seismic network. Blocks were ejected as far as 1.3 km away. Explosions at 1557 and 1615 on 7 November generated ash plumes that rose 3.8 and 3.5 km above the crater rim, respectively. An explosion at 1724 on 8 November generated an ash plume that rose 5.5 km above the crater rim and drifted E, and ejected large blocks that fell 500-800 m away. The last time plumes rose over 5 km from the active vents was on 26 July 2016 at Showa Crater and on 7 October 2000 at Minamidake Crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 October-5 November 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 28 October-5 November. There were 32 explosions and 16 non-explosive eruptive events detected by the seismic network. Eruption plumes rose as high as 2.8 km above the crater rim and large blocks were ejected as far as 1.3 km away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 October-29 October 2019 Citation IconCite this Report

JMA reported that two eruptive events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) recorded during 25-28 October generated plumes that rose 1.2 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 October-22 October 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 15-21 October. There were 14 explosions and seven non-explosive eruptive events detected by the seismic network. Eruption plumes rose as high as 3 km above the crater rim and large blocks were ejected as far as 1.3 km away. The sulfur dioxide emission rate was high, at 2,800 tons/day, on 15 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


9 October-15 October 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 7-15 October. There were 13 explosions detected by the seismic network and nine non-explosive eruptive events. Eruption plumes rose 2.3-2.7 km above the crater rim and large blocks were ejected as far as 1.7 km away. The sulfur dioxide emission rate was high, at 2,100 tons/day, on 11 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


2 October-8 October 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 30 September-7 October. The sulfur dioxide emission rate was high, at 2,000 tons/day, measured during fieldwork on 1 October. An explosion was recorded at 0055 on 4 October but weather clouds prevented visual confirmation. Two explosions during 6-7 October generated ash plumes that rose as high as 2.4 km above the crater rim and ejected large blocks 1.1 km away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 September-1 October 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 24-30 September. Very small eruptive events were recorded. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 September-24 September 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 17-24 September. There were 30 eruptive events, 11 of which were explosive. Plumes rose as high as 2.6 km above the crater rim, and material was ejected as far as 1.7 km from the crater. On 20 September one of the explosions produced an ash plume that rose 3.4 km above the crater rim before merging into weather clouds. Large blocks were ejected 500-700 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 September-17 September 2019 Citation IconCite this Report

JMA reported that inflation at Minamidake crater (at Aira Caldera’s Sakurajima volcano) began to be detected on 9 September and was similar to the deformation recorded just before a notable eruption on 16 June 2018. An eruption recorded at 0746 on 16 September produced an ash plume that rose 2.8 km above the crater rim and drifted SW. A series of eruptive events were recorded during 0830-1110. Deformation ceased after the events. An explosion at 0927 on 17 September generated an ash plume that rose 1 km and ejected blocks as far as 1.1 km. Two eruptive events later than day produced ash plumes that rose 1.6 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 September-10 September 2019 Citation IconCite this Report

JMA reported that at 1549 on 3 September an explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 1.9 km above the crater rim and ejected material as far as 900 m from the vent. Very small eruptive events were detected during 6-9 September. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 August-3 September 2019 Citation IconCite this Report

JMA reported that during 26 August-2 September very small eruptive events were detected at Minamidake crater (at Aira Caldera’s Sakurajima volcano), though none of them were explosive. Crater incandescence was visible in webcams at night during 1-2 September. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


21 August-27 August 2019 Citation IconCite this Report

JMA reported that very small eruptive events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) occasionally occurred during 19-26 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 August-20 August 2019 Citation IconCite this Report

JMA reported that during 13-16 August crater incandescence at Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible in webcams at night. A small eruptive event was recorded on 18 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 August-13 August 2019 Citation IconCite this Report

JMA reported that during 5-13 August very small eruptive events were detected at Minamidake crater (at Aira Caldera’s Sakurajima volcano), though none of them were explosive. Crater incandescence was occasionally visible in webcams at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


31 July-6 August 2019 Citation IconCite this Report

JMA reported that during 30 July-5 August very small eruptive events were detected at Minamidake crater (at Aira Caldera’s Sakurajima volcano), though none of them were explosive. Crater incandescence was occasionally visible in webcams at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 July-30 July 2019 Citation IconCite this Report

JMA reported that on 22 July an explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose to 1.5 km above the crater rim. At 1725 and 1754 on 28 July ash plumes rose 3.5-3.8 km above the crater rim and causing ashfall in areas N of the crater including Kirishima (20 km NE), Shimizu Town, and parts of the Kumamoto Prefecture. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 July-23 July 2019 Citation IconCite this Report

JMA reported that during 19-22 July as many as four explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated ash plumes that rose at least to 1.5 km above the crater rim and ejected material 1.1 km from the vent. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 July-16 July 2019 Citation IconCite this Report

JMA reported that during 8-16 July very small eruptive events were detected at Minamidake crater (at Aira Caldera’s Sakurajima volcano), though none of them were explosive. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 July-9 July 2019 Citation IconCite this Report

JMA reported that at 1044 on 4 July an explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 3.2 km above the crater rim and ejected material 1.1 km from the vent. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


19 June-25 June 2019 Citation IconCite this Report

JMA reported that during 17-21 June very small eruptive events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded, as well as periodic crater incandescence through 24 June. An explosion recorded on 24 June generated a plume that rose 1.6 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 June-18 June 2019 Citation IconCite this Report

JMA reported that inflation at Minamidake crater (at Aira Caldera’s Sakurajima volcano) began at 0500 on 11 June. At 1431 an explosion ejected material 1.2 km from the crater and generated an ash plume that rose 2.2 km above the crater rim. An explosion at 0921 on 13 June was followed by some deflation. Very small eruptive events were recorded during 14-17 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 June-11 June 2019 Citation IconCite this Report

JMA reported that during 3-10 June very small eruptive events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded, as well as periodic crater incandescence. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 May-4 June 2019 Citation IconCite this Report

JMA reported that during 27 May-3 June very small eruptive events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded as well as periodic crater incandescence. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 May-28 May 2019 Citation IconCite this Report

JMA reported that during 22-23 May two explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced plumes that rose 1.6 km above the crater rim and ejected material as far as 900 m. Crater incandescence was periodically visible. Very small eruptive events were recorded during 24-27 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 May-21 May 2019 Citation IconCite this Report

JMA reported that on 13 May two explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced plumes that rose 1.8 km above the crater rim and ejected material as far as 1.3 km. Crater incandescence from the crater was visible. Very small non-explosive events were recorded by the seismic network during 17-20 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 May-14 May 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 7-13 May. Explosions on 7 and 13 May generated plumes that rose 1.6 and 2.9 km above the crater rim, respectively. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 May-7 May 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 29 April-7 May. Five explosions generated plumes that rose as high as 1.6 km above the crater rim. The Tokyo VAAC noted that plumes drifted E, SE, and SW during 1-2, 4, and 6 May. The Alert Level remained at 3 (on a 5-level scale).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


24 April-30 April 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 22-29 April. Three events and one explosion during 22-26 April generated plumes that rose as high as 1.4 km above the crater rim. A small event was recorded on 27 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 April-23 April 2019 Citation IconCite this Report

JMA reported that the sulfur dioxide emission rate at Minamidake crater (at Aira Caldera’s Sakurajima volcano) was somewhat high on 16 April at 1,600 tons/day. An explosion on 17 April generated a plume that rose 2 km above the crater rim and ejected material as far as 900 m. During 19-22 April plumes from two events rose as high as 1.4 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 April-16 April 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 12-15 April. Two events and one explosion generated plumes that rose a maximum of 2.2 km above the crater rim and ejected material as far as 700 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 April-9 April 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 1-8 April. Two explosions on 7 April generated plumes that rose a maximum of 1.3 km above the crater rim and ejected material as far as 1.7 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 March-2 April 2019 Citation IconCite this Report

JMA reported that during 25 March-1 April five events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced plumes that rose as high as 1.6 m above the crater rim. Crater incandescence was occasionally visible. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 March-26 March 2019 Citation IconCite this Report

JMA reported that during 18-22 March there were two events and one explosion recorded at Minamidake crater (at Aira Caldera’s Sakurajima volcano). Plumes rose at least as high as 1.7 km above the crater rim. Small events occasionally occurred during 22-25 March; crater incandescence was visible at night on 24 March. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 March-19 March 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 11-18 March. There were nine events and four explosions detected during 11-15 March ejecting material as far as 1.3 km. One of the events, recorded at 2323 on 14 March generated an ash plume that rose 3.5 km above the crater rim and ejected material as far as 1.1 km. During 16-18 March there were eight events and two explosions. Ash plumes rose as high as 2.7 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 March-12 March 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 4-11 March. Occasional small events and three explosions were detected during 8-11 March. Plumes rose as high as 1.9 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 February-5 March 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 25 February-4 March. There were four events and seven explosive events. Plumes rose as high as 2.3 km, and material as ejected as far as 1.1 km from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 February-26 February 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 18-25 February. At 0059 on 22 February an event generated a plume that rose 1 km above the crater rim and ejected material 600-900 m from the crater. During 22-25 February there were two events, one of which was explosive. Plumes rose as high as 1.2 km, and material as ejected as far as 900 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 February-19 February 2019 Citation IconCite this Report

JMA reported that 12-18 February incandescence was visible from Minamidake crater (at Aira Caldera’s Sakurajima volcano), and two events and two explosions were recorded. One of the explosions occurred at 0624 on 14 February, producing a plume that rose 1.5 km above the crater rim and ejecting material 500-700 m from the crater. An explosion on 17 February generated a plume that rose 2.3 km above the crater rim and ejected material 1-1.3 km from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 February-12 February 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible during 4-12 February. At 1919 on 7 February an event generated a plume that rose 1.3 km above the crater rim and ejected material 1.3-1.7 km from the crater. During 8-12 February there were four events, three of which were explosive. Plumes rose as high as 1.9 km, and boulders were ejected as far as 900 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 January-5 February 2019 Citation IconCite this Report

JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible during 28 January-1 February. An explosion at 1400 on 1 February produced an ash plume that rose 600 m above the crater rim. During a field survey that same day the sulfur dioxide emission rate was high at 3,000 tons/day, an increase from the previous measurement of 1,800 tons/day recorded on 22 January. An explosion at 0228 on 3 February produced an ash plume that rose 1 km and ejected tephra 800-1,100 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 December-18 December 2018 Citation IconCite this Report

JMA reported that there were seven events and an additional five explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 10-17 December, with ash plumes rising as high as 2 km above the crater rim and material ejected as far as 700 m. Crater incandescence was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 December-11 December 2018 Citation IconCite this Report

JMA reported that at least two events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded during 3-10 December, producing plumes that rose as high as 1.1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 November-4 December 2018 Citation IconCite this Report

JMA reported that nine events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded during 26 November-3 December, producing ash plumes that rose as high as 1.8 km above the crater rim. Incandescence was periodically visible at night. An explosion at 0218 on 1 December generated a plume that rose 2.5 km and ejected tephra 1.1 km from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


21 November-27 November 2018 Citation IconCite this Report

JMA reported that four events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were recorded during 19-22 November, producing ash plumes that rose as high as 1.6 km above the crater rim. Material was ejected 500-700 m from the crater. Occasional, very small events occurred during 22-26 November. Crater incandescence was visible at night during 20-21 November, for the first time since 20 September, and continued through 26 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 November-20 November 2018 Citation IconCite this Report

JMA reported that an explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) was recorded at 0043 on 14 November, producing a large ash cloud that rose over 4 km above the crater rim. Incandescent material was ejected more than 1 km from the crater. The report noted that this was the first occurrence of an ash plume rising above 4 km since 16 July 2018. Two events occurred during 16-19 November with the larger plume rising 1.6 km into the clouds. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 November-13 November 2018 Citation IconCite this Report

JMA reported that the sulfur dioxide emission rate at Minamidake crater (at Aira Caldera’s Sakurajima volcano) was high at 1,100 tons/day on 6 November, an increase from the previous measurement of 1,000 tons/day recorded on 23 October. Very small eruptive events were occasionally recorded during 9-12 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


31 October-6 November 2018 Citation IconCite this Report

JMA reported that at 1022 on 30 October an event at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated a plume that rose 1 km above the crater rim. Two explosions occurred during 2-5 November; the larger of the two sent a plume to 2.6 km and ejected material as far as 700 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 October-30 October 2018 Citation IconCite this Report

JMA reported that during 22-26 October seven events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced eruption plumes that rose as high as 1.6 km above the crater rim. Small scale events were occasionally detected through 29 October. The Alert Level remained at 3 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)


17 October-23 October 2018 Citation IconCite this Report

JMA reported that occasional, very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 12-19 October. Sulfur dioxide emissions were slightly less than 400 tons per day on 17 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 October-16 October 2018 Citation IconCite this Report

JMA reported occasional, very small events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 9-15 October. Sulfur dioxide emissions decreased from 3,400 tons/day on 4 October to 600 tons/day on 10 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 October-9 October 2018 Citation IconCite this Report

JMA reported that very small events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) occurred during 1-5 October; no explosions had been detected since 23 September. Sulfur dioxide emissions were 400 tons per day on 1 October, and then increased to 3,400 tons per day on 4 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 September-2 October 2018 Citation IconCite this Report

JMA reported that occasional, very small, events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 25 September-1 October generated plumes that rose 400 m above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


19 September-25 September 2018 Citation IconCite this Report

JMA reported that there were eight events and an additional five explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 18-25 September, with ash plumes rising as high as 2.1 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 September-18 September 2018 Citation IconCite this Report

JMA reported that there were 13 events and also 13 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 10-18 September, with ash plumes rising as high as 1.8 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 September-11 September 2018 Citation IconCite this Report

JMA reported that there were two events and four explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 3-10 September, with ash plumes rising as high as 1.7 km above the crater rim. Crater incandescence was occasionally visible at night. An explosion at 0304 on 9 September ejected material as far as 700 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 August-4 September 2018 Citation IconCite this Report

JMA reported that there were 14 events and 15 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 27 August-3 September, with ash plumes rising as high as 2.8 km above the crater rim and material ejected as far as 1.3 km. Crater incandescence was occasionally visible at night. The sulfur dioxide emission rate was 1,500 tons/day on 27 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 August-28 August 2018 Citation IconCite this Report

JMA reported that there were three events and 12 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 20-27 August, with ash plumes rising as high as 2.1 km above the crater rim and material ejected as far as 1.3 km. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 August-21 August 2018 Citation IconCite this Report

JMA reported that there were four events and nine explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 13-20 August, with ash plumes rising as high as 1.7 km above the crater rim and material ejected as far as 900 m. Crater incandescence was visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 August-14 August 2018 Citation IconCite this Report

JMA reported that there were five events and three explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 6-13 August, with ash plumes rising as high as 1.6 km above the crater rim and material ejected as far as 900 m. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 August-7 August 2018 Citation IconCite this Report

JMA reported that there were eight events and seven explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 30 July-6 August, with ash plumes rising as high as 2.5 km above the crater rim and material ejected as far as 700 m. Crater incandescence was seldom visible at night. Sulfur dioxide emissions were very high at 3,200 tons per day on 2 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 July-31 July 2018 Citation IconCite this Report

JMA reported that there were four events and 11 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 23-30 July, with ash plumes rising as high as 2.5 km above the crater rim and material ejected as far as 1.3 km. Crater incandescence was sometimes visible at night. Sulfur dioxide emissions were 2,100 tons per day on 26 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 July-24 July 2018 Citation IconCite this Report

JMA reported that at 1336 on 17 July an event at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced a plume that rose 1.2 km above the crater rim. Sulfur dioxide emissions were 1,300 tons per day that same day. Occasional small events were recorded during 20-23 July, and crater incandescence was visible on 22 and 23 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 July-17 July 2018 Citation IconCite this Report

JMA reported that there were nine events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 9-17 July generating plumes that rose as high as 2.3 km above the crater rim. At 1538 on 16 July an explosion produced an ash plume that rose 4.6 km, and ejected material as far as 1.7 km E. Crater incandescence was visible at night during 16-17 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 July-10 July 2018 Citation IconCite this Report

JMA reported that there were two events and three explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 2-9 July, with ash plumes rising as high as 1.3 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 June-3 July 2018 Citation IconCite this Report

JMA reported that on 29 June a very small eruption occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano). An explosion at 2319 on 1 July produced an ash plume that rose 400 m above the crater rim and ejected material 500 m away. Crater incandescence was visible at night on 2 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 June-26 June 2018 Citation IconCite this Report

JMA reported that there were four events and one explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 18-25 June, with ash plumes rising as high as 1.9 km above the crater rim. Crater incandescence was visible at night on 18 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 June-19 June 2018 Citation IconCite this Report

JMA reported that there were eight events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 11-15 June, with ash plumes rising as high as 1.6 km above the crater rim. An explosive event at 0719 on 16 June 2018 generated an ash plume that rose 4.7 km (the first time that a plume rose over 4 km since 2 May 2017) and ejecting tephra as far as 1.1 km. A pyroclastic flow traveled down the SW flank. The last pyroclastic flow originated at the Showa Crater on 1 April 2018. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 June-12 June 2018 Citation IconCite this Report

JMA reported that there were eight events and five explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 4-11 June. Crater incandescence was occasionally visible at night. Ash plumes rose up to 2 km above the crater rim, except an event at 1135 on 10 June produced a plume that rose 3.5 km. Tephra was ejected as far as 1.3 km from the crater during 8-11 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 May-5 June 2018 Citation IconCite this Report

JMA reported that there were 12 events and four explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 28 May-4 June. Tephra was ejected as far as 1.1 km from the crater, and ash plumes rose as high as 2.5 km above the crater rim. Crater incandescence was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 May-29 May 2018 Citation IconCite this Report

JMA reported that there were 21 events and 19 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 21-28 May. Tephra was ejected as far as 1.3 km from the crater, and ash plumes rose as high as 3.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 May-22 May 2018 Citation IconCite this Report

JMA reported that there were 13 events and 20 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 14-21 May. Tephra was ejected as far as 1.1 km from the crater, and ash plumes rose as high as 2.7 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


9 May-15 May 2018 Citation IconCite this Report

JMA reported that during 7-11 May there were 12 events, three of which were explosions, at Minamidake crater (at Aira caldera’s Sakurajima volcano). Tephra was ejected as far as 700 m from the crater, and ash plumes rose as high as 2.8 km (9,200 ft) above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


2 May-8 May 2018 Citation IconCite this Report

JMA reported that there were seven events and 15 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 1-7 May. Tephra was ejected as far as 1.3 km from the crater, and ash plumes rose as high as 2.8 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 April-1 May 2018 Citation IconCite this Report

JMA reported that there were nine events and 30 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 20 April-1 May. Tephra was ejected as far as 1.3 km from the crater, and ash plumes rose as high as 3.3 km above the crater rim. Crater incandescence was visible at night on 20, 23, 26, and 30 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 April-24 April 2018 Citation IconCite this Report

JMA reported that there were eight events and 13 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 16-23 April. Tephra was ejected as far as 1.1 km from the crater, and plumes rose as high as 2.5 km above the crater rim. At 0038 on 22 April an explosion produced an ash plume that rose 3.3 km and ejected tephra as far as 1.3 km. Crater incandescence was visible on most nights. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 April-17 April 2018 Citation IconCite this Report

JMA reported that there were four events and nine explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 9-16 April. Tephra was ejected as far as 1.3 km from the crater, and plumes rose as high as 2.5 km above the crater rim. Crater incandescence was visible on most nights. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 April-10 April 2018 Citation IconCite this Report

JMA reported that there were two events and 10 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 2-9 April. Tephra was ejected as far as 1.1 km from the crater, and plumes rose as high as 3.4 km above the crater rim. An event at Showa Crater generated a plume that rose 1.3 km. An explosion at 0909 on 9 April at Minamidake crater ejected large boulders 1.3 km, and produced a plume that rose 1 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 March-3 April 2018 Citation IconCite this Report

JMA reported that there were 16 events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 26 March-2 April, 12 of which were explosive. Tephra was ejected as far as 900 m from the crater. At 1541 on 26 March an explosion generated an ash plume that rose 3.4 km above the crater rim. An explosion recorded at 0740 on 1 April produced an ash plume that rose 3 km. Crater incandescence was visible the morning of 27 March and at night during 30 March-1 April.

During 30 March-2 April there were three events at Showa crater. An event at 1611 on 1 April ejected tephra 300-500 m from the crater, and produced a very small pyroclastic flow (the first since 3 June 2016) that traveled 800 m E. A plume rose 1.7 km above the crater rim, up into weather clouds. The previous eruption at Showa crater occurred on 8 January. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


21 March-27 March 2018 Citation IconCite this Report

JMA reported that there were 20 events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 19-26 March, two of which were explosive. The first explosive event, at 0138 on 21 March, generated a plume that rose 1 km above the crater rim and into weather clouds. At 0228 on 26 March the second explosive event ejected tephra as far as 900 m from the crater and produced a plume that rose 2.8 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 March-20 March 2018 Citation IconCite this Report

JMA reported that during 12-19 March there were seven events and six explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano). Some of the explosions ejected tephra as far as 1.1 km and generated ash plumes that rose 1.7-2.3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 March-13 March 2018 Citation IconCite this Report

JMA reported that on 5 March at 2026 an event at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced an ash plume that rose 1 km above the crater rim, into the clouds. Two explosions were detected on 10 March; one of the events, at 2312, generated ash plumes that rose 1.5 km above the crater rim and ejected material as far as 1.3 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 February-6 March 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 26 February-5 March, two of which were explosive. An explosive event at 0031 on 27 February ejected tephra as far as 700 m and generated a plume that rose 1.3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


21 February-27 February 2018 Citation IconCite this Report

JMA reported that at 0820 on 19 February an explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) generated a plume that rose 1.5 km above the crater rim. An event at 1639 on 24 February produced a plume that rose 800 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 February-20 February 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 13-16 and 19 February. An explosive event at 0820 on 19 February generated a plume that rose 1.5 km above the crater rim up into meteorological clouds. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 February-13 February 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 7-9 February. Crater incandescence from the summit crater was visible during 8-10 February. An event at 2201 on 11 February generated a plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


31 January-6 February 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) on 1 and 3 February. Crater incandescence from the summit crater was visible during 2-3 February. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 January-30 January 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 22-29 January. Crater incandescence from the summit crater was visible during the morning of 29 January. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 January-23 January 2018 Citation IconCite this Report

JMA reported that two of the nine events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were explosive during 15-22 January. Plumes rose as high as 2.5 km above the crater rim, and material was ejected as far as 500 m from the crater. During field observations on 16 January scientists measured a high amount of sulfur dioxide emissions at 2,600 tons/day; the last measurement was 1,800 tons/day on 25 December 2017. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 January-16 January 2018 Citation IconCite this Report

JMA reported that an explosive event occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) at 1020 on 10 January, ejecting material 500-700 m from the crater. Weather clouds obscured views of the emissions. There were three events, two of which were explosive, detected during 12-15 January. The explosions ejected material as far as 500 m from the crater and produced plumes that rose as high as 1.5 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 January-9 January 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 28 December 2017-4 January 2018. An event at 1744 on 6 January ejected material from Minamidake Crater as far as 900 m from the crater. An event at Showa Crater on 8 January at 0359 ejected material as far as 800 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 December-2 January 2018 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake and Showa craters (at Aira Caldera’s Sakurajima volcano) during 25-28 December. An event at 0414 on 25 December ejected material from Minamidake Crater as far as 300 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 December-26 December 2017 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 18-25 December. An event at 0514 on 25 December ejected material as far as 500 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 December-19 December 2017 Citation IconCite this Report

JMA reported that very small events occurred at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) on 14 and 18 December, and at Showa Crater on 16 December. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 December-12 December 2017 Citation IconCite this Report

JMA reported that an explosion at Showa Crater (at Aira Caldera’s Sakurajima volcano) occurred at 1845 on 4 December and generated an ash plume that rose 1.4 km above the crater rim. Very small events occurred at Minamidake Crater during 7 and 9-10 December, and at Showa Crater on 10 December. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 November-5 December 2017 Citation IconCite this Report

JMA reported that an explosion at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) occurred at 1637 on 27 November, and generated an ash plume that rose 2 km above the crater rim. Nighttime crater incandescence was sometimes visible during 27 November-1 December. Very small events occurred at Minamidake Crater on 1 December, and at Showa Crater during 2-3 December. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 November-28 November 2017 Citation IconCite this Report

JMA reported that events at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) were occasionally detected during 20-27 November. Crater incandescence was visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 November-21 November 2017 Citation IconCite this Report

JMA reported that an explosion at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) detected at 2207 on 13 November, ejected material as far as 1.3 km. The explosion vibrated structures in Kagoshima and Miyazaki prefectures. Poor weather conditions prevented views of a plume. An explosion at Showa Crater at 0955 on 14 November produced a plume that rose 1.3 km above the crater rim. Another explosion at Minamidake occurred at 2343 on 14 November, generating a plume that rose 1.3 km above the crater rim. Sulfur dioxide flux measured that same day was 1,400 tons per day, up from 400 tons per day on 10 November. Very small events at Minamidake were occasionally detected during 17-20 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 November-14 November 2017 Citation IconCite this Report

JMA reported that an explosion at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) detected at 1025 on 7 November generated an ash plume that rose 1.3 km above the crater rim. A very small event occurred at the same crater on 13 November. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 November-7 November 2017 Citation IconCite this Report

JMA reported that sulfur dioxide flux at Aira Caldera’s Sakurajima volcano was just under 800 tons per day on 30 October. An explosion at Minamidake summit crater at 1221 on 31 October generated an ash plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


25 October-31 October 2017 Citation IconCite this Report

JMA reported that sulfur dioxide flux at Aira Caldera’s Sakurajima volcano was high at 1,000 and 1,400 tons per day on 23 and 27 October, respectively. Very small events at Minamidake summit crater were detected during 24-25 and 29-30 October. A thermally anomalous area on the SE flank, near Showa Crater, was identified on 25 October using a thermal camera. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 October-24 October 2017 Citation IconCite this Report

JMA reported that a very small event at Showa Crater (at Aira Caldera’s Sakurajima volcano) was detected on 17 October. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 October-17 October 2017 Citation IconCite this Report

JMA reported that during 10-16 October there were 18 events detected at Showa Crater (at Aira Caldera’s Sakurajima volcano), two of which were explosive. Plumes rose as high as 1.9 km above the crater rim, and material was ejected as far as 800 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 October-10 October 2017 Citation IconCite this Report

JMA reported that during 2-10 October there were 19 events detected at Showa Crater (at Aira Caldera’s Sakurajima volcano), three of which were explosive. Plumes rose as high as 1.6 km above the crater rim. An explosion on 5 October ejected material as far as 800 m. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 September-3 October 2017 Citation IconCite this Report

JMA reported that at 0055 on 29 September an explosive event at Showa Crater (at Aira Caldera’s Sakurajima volcano) produced a plume that rose 2.8 km above the crater rim, and ejected material as far as 1,300 m. Two of eight events were explosive during 30 September-2 October; plumes rose 2.8 km and material was ejected 1,300 m away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 September-26 September 2017 Citation IconCite this Report

JMA reported that 29 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) detected during 19-22 September sometimes produced plumes that rose 1.8 km. At 0445 on 24 September an eruption plume rose 1 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 September-19 September 2017 Citation IconCite this Report

JMA reported that during 4-11 September there were 52 events detected at Showa Crater (at Aira Caldera’s Sakurajima volcano), seven of which were explosive and ejected material as far as 500 m. Ash plumes rose as high as 2.4 km above the crater rim. Crater incandescence was observed most nights. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 September-12 September 2017 Citation IconCite this Report

JMA reported that 30 explosive events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 4-11 September ejected material as far as 800 m. Ash plumes rose as high as 2.2 km above the crater rim. Crater incandescence was observed most nights. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 August-5 September 2017 Citation IconCite this Report

JMA reported that six explosive events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 28 August-4 September ejected material as far as 800 m. Ash plumes rose as high as 2.2 km above the crater rim. Crater incandescence was observed at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 August-29 August 2017 Citation IconCite this Report

JMA reported that 17 explosive events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 21-28 August ejected material as far as 800 m. Ash plumes rose as high as 1.4 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 August-22 August 2017 Citation IconCite this Report

JMA reported 26 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 18-21 August, one of which was explosive. Material was ejected as high and as far as 500 m. Ash plumes rose as high as 1.7 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


9 August-15 August 2017 Citation IconCite this Report

JMA reported 44 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 10-14 August, one of which was explosive. Material was ejected as high as 500 m and as far as 300 m. Ash plumes rose as high as 1.8 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 July-1 August 2017 Citation IconCite this Report

JMA reported two events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 24-28 July. One of the events generated an ash plume that rose 2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 July-11 July 2017 Citation IconCite this Report

JMA reported a very small eruption at Showa Crater (at Aira Caldera’s Sakurajima volcano) on 3 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 June-4 July 2017 Citation IconCite this Report

JMA reported that events at Showa Crater (at Aira Caldera’s Sakurajima volcano) at 1811 and 1904 on 27 June generated ash plumes that rose 1 km above the crater rim. Weak incandescence from the crater was noted on 30 June. During 30 June-3 July there were five events, one of which was explosive. Material was ejected as far away as 500 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 June-20 June 2017 Citation IconCite this Report

JMA reported that an event at Showa Crater (at Aira Caldera’s Sakurajima volcano) at 1208 on 15 June generated an ash plume that rose 2.8 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


7 June-13 June 2017 Citation IconCite this Report

JMA reported four events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 5-12 June, one of which was explosive. Material was ejected 800 m away the crater rim. Ash plumes rose as high as 3.2 km on 6 June and 1.9 km on 10 June. A very small event occurred at Minamidake summit crater on 5 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


31 May-6 June 2017 Citation IconCite this Report

JMA reported 15 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 May, two of which were explosive. Material was ejected as high as 800 m above the crater rim. Ash plumes rose as high as 3.4 km on 31 May and 3 km on 2 June. Very small events occurred at Minamidake summit crater during 4-5 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 May-30 May 2017 Citation IconCite this Report

JMA reported 22 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 May, seven of which were explosive. The explosions ejected material as high as 800 m above the crater rim, and as far away as 500 m. Ash plumes rose as high as 3.3 km on 23 May and 3.4 km on 29 May. Crater incandescence was detected on 25 May. A very small event occurred at Minamidake summit crater on 26 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 May-23 May 2017 Citation IconCite this Report

JMA reported that 10 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) were detected during 15-18 May. One of the events, an explosion at 2302 on 17 May, generated a large ash plume that rose 3 km above the crater rim and ejected material 500-800 m from the crater. That same day at 1526 an explosion at Minamidake summit crater produced an ash plume that rose 1.1 km above the crater. At 0058 on 19 May a plume rose 1.4 km above Showa Crater's rim. Very small events occasionally occurred at Minamidake summit crater during 19-22 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 May-16 May 2017 Citation IconCite this Report

According to JMA, fieldwork at Aira Caldera’s Sakurajima volcano revealed that the sulfur dioxide flux rose from 300 tons on 28 April to 1,700 tons on 8 May; the last time sulfur dioxide flux was above 1,000 tons was 23 June 2015. At 1312 on 12 May an explosion at Showa Crater generated a plume that rose 700 m above the crater rim, into a weather cloud. Four events were detected during 13-15 May; one of the events, an explosion at Showa Crater on 14 May, produced a plume that rose 2.3 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 May-9 May 2017 Citation IconCite this Report

JMA reported that nine events at Showa Crater (at Aira Caldera’s Sakurajima volcano) were detected during 1-8 May. One of the events was explosive, generating an ash plume that rose 4 km above the crater rim and ejecting material 300-500 m from the crater. Ashfall was reported in the cities of Kagoshima (3 km NW), Hioki (25 km WNW), and Ichikikushikino (40 km NW). Nighttime crater incandescence was noted on 2 and 5 May. An event at 1213 on 5 May at Minamidake summit crater produced a plume that rose 500 m above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 April-2 May 2017 Citation IconCite this Report

JMA reported that there were less than 10 small events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 26-27 April, the first eruptions at that crater since 26 July 2016. During 28 April-1 May there were 16 events, of which two were explosive, ejecting tephra up to 800 m from the crater. One of the explosive events, at 1101 on 28 April, generated an ash plume that rose 3.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 April-18 April 2017 Citation IconCite this Report

JMA reported that a very small eruption at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) occurred on 16 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


5 April-11 April 2017 Citation IconCite this Report

JMA reported that an explosion from the Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) at 1004 on 4 April generated an ash plume that rose 1.2 km above the crater rim. During field work later that day, scientists observed ashfall in Sakurajima Koike-cho in Kagoshima (3 km NW). The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 March-4 April 2017 Citation IconCite this Report

JMA reported very small eruptions at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) during 28-29 March. Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that on 4 April an ash plume rose to an altitude of 8 km (26,200 ft) a.s.l. and drifted W. The Alert Level remained at 3 (on a 5-level scale).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


22 March-28 March 2017 Citation IconCite this Report

JMA reported that an explosion at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) detected at 1803 on 25 March generated a pyroclastic flow that traveled 1.1 km down the S flank. An explosion at 2228 produced an ash plume that rose 1.4 km above the crater rim. Ash fell in the vicinity of the volcano and as far as 4.5 km E. Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that ash plumes drifted SE and E that same day.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


17 August-23 August 2016 Citation IconCite this Report

JMA reported that small-scale explosions occasionally occurred at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) during 15-19 August. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 August-16 August 2016 Citation IconCite this Report

JMA reported that during 10-13 and 15 August small-scale explosions occurred at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano). The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 August-9 August 2016 Citation IconCite this Report

JMA reported that on 4 August a small-scale explosion occurred at Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) ejecting material as high as 400 m above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 July-2 August 2016 Citation IconCite this Report

JMA reported that on 26 July an explosive eruption at Showa Crater (at Aira Caldera’s Sakurajima volcano) ejected tephra 800 m away from the crater and generated an ash plume that rose 5 km above the crater rim. Significant amounts of ash fell in the W and SW parts of the island and in multiple areas of Kagoshima (10-12 km W). The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


29 June-5 July 2016 Citation IconCite this Report

JMA reported that a small-scale explosion at Showa Crater (at Aira Caldera’s Sakurajima volcano) occurred at 1336 on 29 June. An explosion at 0413 on 2 July generated an ash plume that rose 1.2 km above the crater rim, and ejected tephra as far as 800 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 June-7 June 2016 Citation IconCite this Report

JMA reported that on 3 June explosions at Showa Crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 1.3 km above the crater rim, and a small pyroclastic flow that traveled 400 m SE. Tephra was ejected 800 m from the crater. A small-scale explosion occurred at Minamidake summit crater that same day; an ash plume rose 1.5 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


18 May-24 May 2016 Citation IconCite this Report

JMA reported that Aira Caldera’s Sakurajima volcano remained vigorously active. During 16-23 May the seismic network detected 15 explosions at Showa Crater, generating ash plumes that rose as high as 3.5 km above the crater rim (on 16 May). A small-scale explosion occurred at Minamidake summit crater on 18 May. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


11 May-17 May 2016 Citation IconCite this Report

JMA reported that an explosion at the Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 3.7 km above the crater rim. During 13-16 May explosions from Showa Crater generated an ash plume that rose as high as 3.5 km above the crater rim. On 13 May the Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


4 May-10 May 2016 Citation IconCite this Report

JMA reported that on 8 May explosions from Showa Crater (at Aira Caldera’s Sakurajima volcano) generated an ash plume that rose 3.3 km above the crater rim and ejected tephra as far as 1.3 km from the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 April-26 April 2016 Citation IconCite this Report

JMA reported that a small-scale explosion at the Minamidake summit crater (at Aira Caldera’s Sakurajima volcano) was detected on 20 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 April-19 April 2016 Citation IconCite this Report

JMA reported that during 11-15 April the seismic network at Aira Caldera’s Sakurajima volcano detected seven eruptions at Showa Crater. An event at 1924 on 17 April generated an ash plume that rose 2.2 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 April-12 April 2016 Citation IconCite this Report

JMA reported that during 4-8 April the seismic network at Aira Caldera’s Sakurajima volcano detected four explosions at Showa Crater, generating ash plumes that rose as high as 3.5 km above the crater rim. One of the explosions, recorded at 1333 on 6 April, produced an ash plume that rose 3.5 km. An explosion at 1922 on 8 April generated an ash plume that rose 3.7 km and ejected cinders as far as 1.3 km away. Small-scale explosions occurred at Minamidake summit crater on 5, 6, and 9 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 March-5 April 2016 Citation IconCite this Report

JMA reported that on 1 April an explosion at Aira Caldera’s Sakurajima volcano generated an ash plume that rose 2 km above Showa's crater rim. An explosion at Minamidake summit crater also produced an ash plume which rose 800 m above its crater rim. Three of five explosions detected at Showa during 1-4 April generated ash plumes that rose as high as 3.5 km, and ejected tephra as far as 1,300 m. Reports of falling tephra, 2 cm in diameter, came from a town 3 km away. At 0608 on 3 April an ash plume from an explosion rose 700 m above Minamidake. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 March-29 March 2016 Citation IconCite this Report

JMA reported that an explosion at 0159 on 24 March from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 800 m, and generated an ash plume that rose 2.1 km above the crater rim. At 0825 on 25 March an explosion at Minamidake summit crater produced an ash plume that rose 2 km above the crater rim. Two explosions at Showa Crater, detected at 0248 and 1044 on 26 March, sent ash plumes as high as 2.7 km and ejected tephra 1.3 km away onto the flanks. Tephra 8 mm in diameter fell 4 km away. Ash from an explosion at Minamidake rose as high as 2 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 March-22 March 2016 Citation IconCite this Report

JMA reported that small-scale explosions from Minamidake Crater at Aira Caldera’s Sakurajima volcano were detected during 14-15 March. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


9 March-15 March 2016 Citation IconCite this Report

JMA reported that at 1820 on 8 March an explosion from Minamidake Crater at Aira Caldera’s Sakurajima volcano generated a plume that rose 1.9 km above the crater rim. During an overflight on 11 March scientists observed a white plume rising 500 m above Minamidake. Later that day, at 2007, an explosion produced a plume that rose 1.7 km.

Source: Japan Meteorological Agency (JMA)


2 March-8 March 2016 Citation IconCite this Report

During 29 February-4 March JMA reported that two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 500 m. At 0038 on 4 March an explosion at Minamidake summit crater generated an ash plume that rose 1.6 km. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 February-23 February 2016 Citation IconCite this Report

During 15-22 February JMA reported that six explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. A small-scale eruption occurred from Minamidake summit crater on 20 February. The Alert Level remained at 3 (on a 5-level scale).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


10 February-16 February 2016 Citation IconCite this Report

During 8-15 February JMA reported that 11 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Based on JMA reports and satellite data, the Tokyo VAAC reported that during 10-12 February ash plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N, NW, W, S, and SE. On 14 February a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted S. The Alert Level remained at 3 (on a 5-level scale).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


3 February-9 February 2016 Citation IconCite this Report

JMA reported that an explosive eruption at Showa Crater (at Aira Caldera’s Sakurajima volcano) began at 1856 on 5 February and generated an ash plume that rose 1.3-1.8 km above the crater rim. Lightning was observed in the ash cloud, and incandescent tephra was ejected as far as 1.8 km onto the flanks. The Alert Level was raised to 3 (on a 5-level scale); it had previously been lowered to 2 on 25 November 2015. During an overflight the next day scientists did not see any significant changes to the crater; a plume obscured views of Minamidake summit crater. Sulfur dioxide emissions were 100 tons/day, which was the same level measured on 3 February.

Explosions were detected on 8 February. Based on JMA reports and satellite data, the Tokyo VAAC reported that during 8-9 February ash plumes rose to altitudes of 1.5-3.3 km (5,000-11,000 ft) a.s.l. and drifted E and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


4 November-10 November 2015 Citation IconCite this Report

JMA reported that during 2-6 November two small-scale eruptions occurred at Showa Crater, at Aira Caldera’s Sakurajima volcano. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


28 October-3 November 2015 Citation IconCite this Report

JMA reported that on 30 October and 2 November small-scale events occurred at Showa Crater, at Aira Caldera’s Sakurajima volcano. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


14 October-20 October 2015 Citation IconCite this Report

JMA reported that during 13-16 October small scale explosions occurred at Showa Crater, at Aira Caldera’s Sakurajima volcano. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


30 September-6 October 2015 Citation IconCite this Report

JMA reported that during 28 September-2 October emissions rose from both Showa Crater and Minami-Dake Crater at Aira Caldera’s Sakurajima volcano. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


23 September-29 September 2015 Citation IconCite this Report

JMA reported that during 21-28 September emissions rose from both Showa Crater and Minami-Dake Crater at Aira Caldera’s Sakurajima volcano. An explosion at Minami-Dake Crater at 0233 on 28 September generated a plume that rose 2.7 km above the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


16 September-22 September 2015 Citation IconCite this Report

JMA reported that small explosions occasionally occurred at Minamidake Crater at Aira Caldera’s Sakurajima during 14-21 September. On 16 and 18 September an explosion from Showa Crater ejected tephra as far as 800 m, and incandescence from the crater was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


2 September-8 September 2015 Citation IconCite this Report

JMA reported 30 explosions during 31 August-7 September from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater that was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


26 August-1 September 2015 Citation IconCite this Report

JMA reported that small-scale explosions from Showa Crater (Aira Caldera’s Sakurajima volcano) were detected during 28-29 August. An ash plume rose 800 m above the crater on 29 August. Small explosions occurred at Minamidake Crater on 30 August. The Alert Level was lowered to 3 (on a 5-level scale) on 1 September.

Source: Japan Meteorological Agency (JMA)


19 August-25 August 2015 Citation IconCite this Report

JMA reported that a small-scale explosion from Showa Crater (Aira Caldera’s Sakurajima volcano) occurred on 19 August. In a report from 21 August JMA noted that the possibility of larger-scale eruption had decreased since 15 August. Deformation data during 15-16 August suggested a dike intrusion beneath Minamidake Crater, centered 1-3 km below sea level, with an estimated volume of 2 million cubic meters. Small-scale explosions at Showa Crater occurred on 21 and 23 August. The Alert Level remained at 4 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


12 August-18 August 2015 Citation IconCite this Report

On 15 August JMA reported an increase in the frequency of volcanic earthquakes detected under Minami-Dake Crater (Aira Caldera’s Sakurajima volcano) and that inflation became more rapid. This activity suggested an increase in the possibility of larger-scale explosions, prompting JMA to raise the Alert Level to 4 (on a 5-level scale). Elevated activity continued to be detected through 18 August.

Source: Japan Meteorological Agency (JMA)


5 August-11 August 2015 Citation IconCite this Report

JMA reported that explosions at Showa Crater (Aira Caldera’s Sakurajima volcano) occurred twice during 3-7 August, ejecting tephra as far as 500 m away from the crater. An explosion on 8 August ejected tephra 800 m away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


22 July-28 July 2015 Citation IconCite this Report

JMA reported that during 21-24 July a small-scale, non-explosive event at Showa Crater (Aira Caldera’s Sakurajima volcano) was recorded, and incandescence from the crater was visible on 23 July. An explosion on 25 July ejected tephra as far as 800 m away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


15 July-21 July 2015 Citation IconCite this Report

JMA reported five explosions during 13-21 July from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 500 m, and incandescence from the crater that was occasionally visible. A small-scale eruption occurred from Minami-Dake Crater on 16 July. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


8 July-14 July 2015 Citation IconCite this Report

JMA reported that during 6-13 July small-scale explosions occurred at Showa Crater at Aira Caldera’s Sakurajima volcano. One larger explosion ejected ballistics 200-300 m above the crater. Incandescence from the crater was occasionally visible at night. Rumbling was occasionally heard several tens of kilometers away. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


1 July-7 July 2015 Citation IconCite this Report

JMA reported 14 explosions during 29 June-6 July from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater that was occasionally visible. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


24 June-30 June 2015 Citation IconCite this Report

JMA reported 26 explosions during 22-29 June from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater that was visible during 22-23 and 27 June. A small-scale eruption occurred from Minami-Dake Crater on 22 June. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


17 June-23 June 2015 Citation IconCite this Report

JMA reported 15 explosions during 15-22 June from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 800 m, and incandescence from the crater that was occasionally visible at night. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


10 June-16 June 2015 Citation IconCite this Report

JMA reported that incandescence from Showa Crater at Aira Caldera’s Sakurajima volcano was visible at night on 13 June. An explosion occurred at 1007 on 15 June but inclement weather prevented visual observations. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


3 June-9 June 2015 Citation IconCite this Report

JMA reported 14 explosions during 1-5 June from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater that was occasionally visible at night. Explosive eruptions on 4 June generated small-scale pyroclastic flows that descended the E flank of Showa Crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


27 May-2 June 2015 Citation IconCite this Report

JMA reported 18 explosions during 25-29 May and 24 during 29 May-1 June from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater was occasionally visible at night. On 29 May and 1 June explosions generated large ash plumes that rose 3.3 km above the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


20 May-26 May 2015 Citation IconCite this Report

JMA reported 19 explosions during 18-25 May from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,300 m, and incandescence from the crater was occasionally visible at night. During 21-22 May explosions generated ash plumes that rose 3-4.3 km above the crater. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


13 May-19 May 2015 Citation IconCite this Report

JMA reported 31 explosions during 11-18 May from Showa Crater at Aira Caldera’s Sakurajima volcano, some that ejected tephra as far as 1,800 m. Incandescence from the crater was visible at night on 11 May. The next day a very small explosion at Minami-Dake Crater generated a 200-m-high plume. Three larger explosions from Showa Crater, at 2104 and 2200 on 13 May, and 0416 on 14 May, generated ash plumes that rose as high as 3.5 km. Tephra, about 2 cm in diameter, and ashfall reported in Kagoshima Kurokami was attributed to the explosion at 2104 on 13 May. During 15-18 May ash plumes rose as high as 3 km twice, except from an explosion at 1732 on 17 May, an event that produced a 3.8-km-high ash plume. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)


6 May-12 May 2015 Citation IconCite this Report

JMA reported 105 explosions during 1-11 May from Showa Crater at Aira Caldera’s Sakurajima volcano tephra was ejected as far as 1,800 m. Incandescence from the crater was visible at night. Explosions occurred at 2309 on 4 May, and at 1049 and 1126 on 8 May. Sulfur dioxide gas emissions measured during fieldwork conducted on 8 May were 2,300 tons per day (400 tons per day was measured on 16 April). An explosion at 2021 on 10 May generated a large ash plume that rose 3.2 km.

Source: Japan Meteorological Agency (JMA)


29 April-5 May 2015 Citation IconCite this Report

JMA reported that 12 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 27 April-1 May. Incandescence from the crater was visible at night. An explosion at 0720 on 27 April generated a large ash plume that rose 3.5 km above the crater. The next day an explosive eruption was detected by the seismic network for 40 minutes. A very small pyroclastic flow traveled 500 m down the SE flank of Showa Crater. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 29 April-5 May generated plumes which rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted in multiple directions.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


22 April-28 April 2015 Citation IconCite this Report

JMA reported that 29 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 20-24 April. Nine of the explosions generated ash plumes that rose 3 km above the crater rim; one explosion, on 24 April, produced an ash plume that rose 4 km. Incandescence from the crater was visible on one night. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 22-28 April generated plumes which rose to altitudes of 1.5-4.9 km (5,000-16,000 ft) a.s.l. and drifted S, SE, E, NE, and N.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


15 April-21 April 2015 Citation IconCite this Report

JMA reported 23 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano during 13-17 April. Incandescence from the crater was visible at night on 14 April. An explosion at 1355 on 17 April generated a large ash plume that rose 3 km above the crater, and a second explosion ejected tephra as far as 1,800 m. Inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 15-18 and 20-21 April generated plumes which rose to altitudes of 1.2-4.6 km (4,000-15,000 ft) a.s.l. and drifted E and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


8 April-14 April 2015 Citation IconCite this Report

JMA reported that 15 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 6-10 April. Incandescence from the crater was visible at night on 7 and 9 April, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 8-13 April generated plumes which rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted in multiple directions. Pilots observed ash plumes that rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) and drifted E and SE during 10-11 April.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


1 April-7 April 2015 Citation IconCite this Report

JMA reported that 20 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 30 March-3 April. Incandescence from the crater was periodically visible at night, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 1-2, 5, and 7 April generated plumes which rose to altitudes of 1.5-3.4 km (5,000-11,000 ft) a.s.l. and drifted E and NE. Pilots observed ash plumes that rose to an altitude of 3 km (10,000 ft) on 1 April and 1.5 km (5,000 ft) a.s.l. on 7 April.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


18 March-24 March 2015 Citation IconCite this Report

Based on JMA notices, the Tokyo VAAC reported explosions from Aira Caldera’s Sakurajima volcano during 18-25 March; plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted S, SE, E, and NE during 18-19 and 21-25 March. JMA reported that 19 explosions from Showa Crater ejected tephra as far as 1,300 m during 20-23 March. Incandescence from the crater was periodically visible at night, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


11 March-17 March 2015 Citation IconCite this Report

JMA reported that 10 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 13-16 March. Incandescence from the crater was periodically visible at night, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that during 11-17 March plumes rose to altitudes of 1.8-4.3 km (6,000-14,000 ft) a.s.l. and drifted SE, E, and N.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


4 March-10 March 2015 Citation IconCite this Report

JMA reported that seven explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 2-6 March. Incandescence from the crater was periodically visible at night, and inflation continued to be detected. During a field survey conducted on 4 March scientists observed deposits of tephra, up to 2 cm in diameter, in an area 3 km S of Showa Crater. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 4-5 and 7-8 March plumes rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. and drifted in multiple directions.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


25 February-3 March 2015 Citation IconCite this Report

JMA reported that eight explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 23-27 February. An explosion on 24 February generated an ash plume that rose 3.3 km. Incandescence from the crater was visible at night on 25 and 27 February, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 25-28 February and 2-3 March plumes rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted N, NE, E, and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


18 February-24 February 2015 Citation IconCite this Report

JMA reported that 10 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 16-20 February. Incandescence from the crater was visible at night on 19 February, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 18-24 February plumes rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted in multiple directions.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


11 February-17 February 2015 Citation IconCite this Report

JMA reported that 36 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 9-13 February. Incandescence from the crater was visible at night during 9-11 February, and inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 11-17 February plumes rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E and SE. On 17 February pilots observed ash plumes that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


4 February-10 February 2015 Citation IconCite this Report

The Tokyo VAAC reported that during 28 January-3 February plumes from Aira Caldera’s Sakurajima volcano rose to altitudes of 1.5-3.3 km (5,000-11,000 ft) a.s.l. and drifted NE, E, SE, and S. On 1 February pilots observed ash plumes that rose to altitudes of 2.7-3.3 km (9,000-11,000 ft) a.s.l. JMA reported that nine explosions from Showa Crater ejected tephra as far as 1,800 m during 26-30 January. Incandescence from the crater was visible at night, and inflation continued to be detected. An explosion on 30 January caused tephra fall (2 cm in diameter) in Kagoshima Kurokami (3.5 km E). The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


28 January-3 February 2015 Citation IconCite this Report

The Tokyo VAAC reported that during 28 January-3 February plumes from Aira Caldera’s Sakurajima volcano rose to altitudes of 1.5-3.3 km (5,000-11,000 ft) a.s.l. and drifted NE, E, SE, and S. On 1 February pilots observed ash plumes that rose to altitudes of 2.7-3.3 km (9,000-11,000 ft) a.s.l. JMA reported that nine explosions from Showa Crater ejected tephra as far as 1,800 m during 26-30 January. Incandescence from the crater was visible at night, and inflation continued to be detected. An explosion on 30 January caused tephra fall (2 cm in diameter) in Kagoshima Kurokami (3.5 km E). The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


21 January-27 January 2015 Citation IconCite this Report

JMA reported that three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 800 m during 19-23 January. Incandescence from the crater was visible at night on 22 January. Inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 23 January plumes rose to altitudes of 3-4.9 km (10,000-16,000 ft) a.s.l. and drifted SE. During 24-27 January plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE, E, NE, and N.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


14 January-20 January 2015 Citation IconCite this Report

The Tokyo VAAC reported that during 15 and 17-20 January plumes from Aira Caldera’s Sakurajima volcano rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted S, SE, and E. The Alert Level remained at 3 (on a scale of 1-5). JMA reported that five explosions from Showa Crater ejected tephra as far as 1,300 m during 16-19 January. Incandescence from the crater was visible at night on 16 January. Inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


7 January-13 January 2015 Citation IconCite this Report

JMA reported that four explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 5-9 January. Incandescence from the crater was visible at night during 7-8 January. Inflation continued to be detected. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 7-8, 10, and 12-13 January plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE, SW, and NW. On 8 and 10 January pilots observed ash plumes that rose to altitudes of 1.5 km (10,000 ft) a.s.l. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


31 December-6 January 2015 Citation IconCite this Report

The Tokyo VAAC reported that during 1-6 January plumes from Aira Caldera’s Sakurajima volcano rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE and S. During 3-5 January pilots observed ash plumes that rose to altitudes of 1.8-4 km (6,000-13,000 ft) a.s.l. On 6 January JMA reported that inflation at Sakurajima had been detected during the previous few days. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


10 December-16 December 2014 Citation IconCite this Report

JMA reported that four explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,800 m during 8-12 December. Incandescence from the crater was visible at night during 11-12 December. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported plumes during 11, 13, and 15-16 December that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted SE and NE. On 11 December a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted NE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


3 December-9 December 2014 Citation IconCite this Report

JMA reported that three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,800 m during 5-8 December. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 4 and 6-8 December plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE and E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


26 November-2 December 2014 Citation IconCite this Report

JMA reported that periodic, small-scale explosions from Showa Crater at Aira Caldera’s Sakurajima were detected during 25-28 November. Weak incandescence from the crater was visible during 25-26 November. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 27-30 November plumes rose to altitudes of 1.5-4.9 km (5,000-16,000 ft) a.s.l. and drifted NE, E, and SE. An eruption on 2 December generated a plume that rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


19 November-25 November 2014 Citation IconCite this Report

JMA reported that two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 17-21 November. Weak incandescence from the crater was visible during 18-19 November. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 19 November an explosion produced a plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted NE. An eruption on 23 November generated a plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


12 November-18 November 2014 Citation IconCite this Report

JMA reported that three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 800 m during 10-14 November. Incandescence from the crater was visible during 12-13 November. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 12-17 November plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted E and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


5 November-11 November 2014 Citation IconCite this Report

JMA reported that nine explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 4-7 November. An explosive eruption on 7 November generated an ash plume that rose 3.5 km. An eruption later that day from Minami-Dake Crater produced a plume that rose 1.4 km. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 5-8 November plumes rose to altitudes of 2.1-4.6 km (7,000-15,000 ft) a.s.l. and drifted NW, W, E, and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


29 October-4 November 2014 Citation IconCite this Report

The Tokyo VAAC reported an explosion from Showa Crater at Aira Caldera’s Sakurajima volcano on 1 November. Explosions on 2 November generated ash plumes that rose to altitudes of 2.4-3 m (8,000-10,000 ft) a.s.l. and drifted E and SE. During 3-4 November ash plumes rose to altitudes of 3-3.7 km (10,000-12,000 ft) a.s.l. and drifted S and W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 October-28 October 2014 Citation IconCite this Report

JMA reported that two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano were detected during 20-24 October; an explosion on 24 October generated a plume that rose 3.2 km. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 24 October ash plumes rose to altitudes of 3-4.6 km (10,000-15,000 ft) a.s.l. and drifted E. During 25-26 October plumes rose to altitudes of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted E. On 28 October plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted S.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


15 October-21 October 2014 Citation IconCite this Report

JMA reported that three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 14-17 October. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 16, 18, and 21 October ash plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted S, SE, and NE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


8 October-14 October 2014 Citation IconCite this Report

JMA reported that six explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 6-10 October. Incandescence from Showa Crater was visible at night. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 9-10 October plumes rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted W.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


1 October-7 October 2014 Citation IconCite this Report

JMA reported that five explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m from the crater during 29 September-3 October. Incandescence from Showa Crater was visible at night during 2-3 October. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 2-7 October plumes rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted in multiple directions. On 2 October a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


24 September-30 September 2014 Citation IconCite this Report

JMA reported that 12 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 26-29 September. Incandescence from Showa Crater was visible at night during 26-27 September. An explosion on 28 September produced a dense ash plume that rose 3 km. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 24-30 September plumes rose to altitudes of 1.8-4 km (6,000-13,000 ft) a.s.l. and drifted W, S, SE, and E. On 27 September a pilot observed an ash plume that rose to an altitude of 4.3 km (14,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


17 September-23 September 2014 Citation IconCite this Report

JMA reported that 24 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 16-19 September. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 17-23 September plumes rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted in multiple directions. During 17-18 and 23 September pilots observed ash plumes that rose to altitudes of 2-3 km (7,000-10,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


10 September-16 September 2014 Citation IconCite this Report

During 8-16 September JMA maintained Alert Level 3 for Aira Caldera’s Sakurajima volcano. Volcanic earthquakes and tremor were detected during this time period. There were 12 explosions that ejected tephra up to 1,300 m above Showa crater. Sustained eruptions from the crater were recorded on 10 and 11 September and nighttime incandescence was detected during 11-16 September.

During 10-16 September JMA reported ash eruptions, causing the Tokyo VAAC to issue regular advisories; however, ash was not visible in satellite images.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


3 September-9 September 2014 Citation IconCite this Report

During 1-9 September JMA maintained Alert Level 3 for Aira Caldera’s Sakurajima volcano. There were 23 explosions recorded from Showa crater from 1 to 4 September; during 5-7 September there were 18 explosions.

During 3-7 September JMA reported ash eruptions, causing the Tokyo VAAC to issue regular advisories; however, ash was not visible in satellite images. At 0437 on 9 September, ash was visible in satellite images and reached 3,300 m (11,000 ft) a.s.l. drifting S. On 2 and 3 September, ballistics reached 1,300-1,800 m above the crater. Nighttime incandescence was detected during 4-5 September from Showa crater. Volcanic earthquakes and tremor were detected during 1-8 September.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


27 August-2 September 2014 Citation IconCite this Report

During 27 August-2 September JMA reported 42 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano that ejected ballistics 800-1300 m from the crater. The explosions were accompanied by volcanic earthquakes and volcanic tremor. On 30-31 August clear incandescence was visible by high-sensitivity camera at night, with a “smoke” plume rising 3 km above the crater on the 31st. The Tokyo VAAC reported explosions during 13-17 August with plumes that rose to an altitude of 1.2-4 km (4,000-13,000 ft) a.s.l. and drifted E, NE, N, and SE. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


20 August-26 August 2014 Citation IconCite this Report

During 20-26 August JMA reported 17 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano that were accompanied by volcanic earthquakes and volcanic tremor, and which ejected ballistics 500-800 m away. On 20-24 August clear incandescence was visible using high-sensitivity camera at night. On 20-26 August the Tokyo VAAC reported explosions with plumes that rose to an altitude of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted NE and N, though volcanic ash could not be identified in satellite data. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Japan Meteorological Agency (JMA)


13 August-19 August 2014 Citation IconCite this Report

During 11-15 August JMA reported 14 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano that ejected ballistics 800-1300 m away. During 15-18 August were four more explosions with similar ballistic ejections. The explosions were accompanied by volcanic earthquakes and volcanic tremor. On most days faint to clear incandescence was visible using a high-sensitivity camera at night. On 13-17 August the Tokyo VAAC reported explosions with plumes that rose to an altitude of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted NE and N, though volcanic ash could not be identified in satellite data. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


6 August-12 August 2014 Citation IconCite this Report

JMA reported an explosion from Showa Crater at Aira Caldera’s Sakurajima volcano on 6 August that ejected ballistics 300-500 m from Showa crater and a plume that rose 500 m above the crater. On 10 August three explosions ejected ballistics 500-800 m from Showa crater accompanied by volcanic earthquakes and volcanic tremor. On 6-11 August, incandescence was clearly visible at night by high-sensitivity camera. The Tokyo VAAC reported that plumes from explosions on 6, 8-10 August rose to an altitude of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted NW, N, E, SE, and S. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


30 July-5 August 2014 Citation IconCite this Report

JMA reported an explosion from Showa Crater at Aira Caldera’s Sakurajima volcano on 30 July that ejected ballistics 300-500 m from Showa crater and six other explosions on 31 July accompanied by volcanic earthquakes and volcanic tremor. In general, explosions, volcanic tremor and volcanic earthquakes decreased 1-4 August. On 31 July-4 August, incandescence was clearly visible by high-sensitivity camera at night. The Tokyo VAAC reported that a plume from the 30 July explosion rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted NW. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


23 July-29 July 2014 Citation IconCite this Report

JMA reported three explosive eruptions from Showa Crater at Aira Caldera’s Sakurajima volcano on 22, 25, and 27 July that ejected ballistics 300-800 m away. In general, the eruptions were accompanied by volcanic earthquakes and increasing volcanic tremor. On 28 July a very small eruption cloud rose 200 m above Minami-Dake Crater. The Tokyo VAAC reported that on 23, 25, and 27 July plumes rose to an altitude of 1.5-2.5 km (5,000-8,000 ft) a.s.l. and drifted E and NE. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


16 July-22 July 2014 Citation IconCite this Report

JMA reported that seven explosive eruptions from Showa Crater at Aira Caldera’s Sakurajima volcano during 14-22 July ejected ballistics 500-800 m from Showa crater. In general, volcanic earthquakes decreased and tremor increased. The Tokyo VAAC reported that during 16-20 July plumes rose to an altitude of 2-3 km (7,000-10,000 ft) a.s.l. and drifted E and SE; on 22 July a plume rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted N. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


9 July-15 July 2014 Citation IconCite this Report

During 11-14 July, JMA reported four large explosions that ejected deposits 800-1,300 m from Showa crater. Volcanic earthquakes decreased and tremor continued. The Tokyo VAAC reported that during 3-14 July plumes rose to altitudes of 2-3 km (7,000-10,000 ft) a.s.l. and drifted NE, SE, and E. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


25 June-1 July 2014 Citation IconCite this Report

JMA reported that during 23-27 June six explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. During 27-30 June there were four explosions. A significant explosion on 29 June lasted for 17 minutes.The Tokyo VAAC reported that during 25 June-1 July plumes rose to altitudes of 1.2-3.9 km (4,000-13,000 ft) a.s.l. and drifted NW, SE, and E. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


18 June-24 June 2014 Citation IconCite this Report

JMA reported that during 13-23 June, 4-10 explosions occurred each day from Showa Crater at Aira Caldera’s Sakurajima volcano. Tephra ejected from these events landed as far as 1,800 m away. A significant explosion on 19 June lasted for 17 minutes; the plume rose ~3,000 m above the crater rim and tephra was ejected to a distance of 1,300-1,800 m. Field surveys conducted on 12 June determined an SO2 flux of 270 tons/day (previous measurement of 2,300 tons/day was measured on 9 May). During this reporting period there was no activity from Minamidake summit crater.

The Tokyo VAAC reported that volcanic ash was visible in satellite images at 0541 on 23 June. The plume reached 1,830 m (6,000 ft) a.s.l. and drifted SE.

Sources: Japan Meteorological Agency (JMA) via the Volcano Research Center; Tokyo Volcanic Ash Advisory Center (VAAC)


4 June-10 June 2014 Citation IconCite this Report

JMA reported that during 19-23 May two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra that landed as far as 1,300 m away. Incandescence from the crater was detected at night during 19-20 May. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 6 and 9 June plumes rose to altitudes of 2.1-5.5 km (7,000-18,000 ft) a.s.l. Plumes drifted NW on 9 June.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


28 May-3 June 2014 Citation IconCite this Report

Based on JMA notices, the Tokyo VAAC reported that on 31 May explosions from Aira Caldera’s Sakurajima volcano generated plumes that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 May-27 May 2014 Citation IconCite this Report

JMA reported that during 19-23 May two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night during 19-20 May. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 23-25 May plumes rose to altitudes of 2.4-4 km (8,000-13,000 ft) a.s.l. and drifted S, SE, and N.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


14 May-20 May 2014 Citation IconCite this Report

JMA reported that an explosion from Showa Crater at Aira Caldera’s Sakurajima volcano at 2229 on 12 May ejected tephra as far as 1.8 km from the crater and produced a plume that rose 1.6 km above the crater rim. Incandescence from the crater was detected at night during 13-14 May.

Source: Japan Meteorological Agency (JMA)


7 May-13 May 2014 Citation IconCite this Report

JMA reported that a small non-explosive eruption from Showa Crater at Aira Caldera’s Sakurajima volcano occurred during 7-9 May. Incandescence from the crater was detected at night. A very small eruption at Minamidake Crater at 1151 on 8 May produced a plume that rose 400 m above the crater rim. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 10 and 12 May plumes rose to altitudes of 2.4-5.5 km (8,000-18,000 ft) a.s.l. and drifted W, SE, and E. On 13 May a pilot observed an ash plume that rose to an altitude of 1.2 km (4,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


30 April-6 May 2014 Citation IconCite this Report

JMA reported that during 28 April-2 May four explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 500 m. Incandescence from the crater was detected at night during 28-30 April. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 30 April-3 May and on 5 May plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted E, SE, and SW. On 30 April a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


23 April-29 April 2014 Citation IconCite this Report

JMA reported that seven explosions from Showa Crater at Aira Caldera’s Sakurajima volcano during 22-25 April ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 23-24 and 26 April plumes rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted NW, W, and SE. On 26 April a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted WNW. An explosion was reported on 29 April.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


9 April-15 April 2014 Citation IconCite this Report

JMA reported that during 7-11 April two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 800 m. Incandescence from the crater was detected during the night of 10 April. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 10 and 12 April plumes rose to an altitude of 2.4 km (8,000 ft) a.s.l. Plumes drifted SE on 10 April.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


2 April-8 April 2014 Citation IconCite this Report

JMA reported that during 31 March-4 April two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was occasionally detected at night. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that. During 2 and 5-7 April plumes rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted SW, S, SE, and E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


26 March-1 April 2014 Citation IconCite this Report

JMA reported that 20 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano during 24-28 March ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night on 25 March. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported an explosion on 26 March. During 27-29 March plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted SE, N, and NW.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


19 March-25 March 2014 Citation IconCite this Report

JMA reported that during 17-20 March five explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night during 17-18 March. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 20-25 March plumes rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted SE, SW, N, and NE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


12 March-18 March 2014 Citation IconCite this Report

JMA reported that during 10-14 March two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night. Volcanologists conducting a field survey on 10 March noted that sulfur dioxide emissions were 190 tons per day, lower than the 1,900 tons per day they measured on 4 March. The Alert Level remained at 3 (on a scale of 1-5).

The Tokyo VAAC reported explosions during 12 and 15-17 March. On 12 March pilots observed ash plumes that rose to altitudes of 1.2-1.8 km (4,000-6,000 ft) a.s.l. and drifted N. During 15-18 March plumes rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted E, SE, and S. Pilots observed ash plumes drifting SE at an altitude of 3.4 km (11,000 ft) a.s.l. on 16 March, and drifting SE at an altitude of 3 km (10,000 ft) a.s.l. on 18 March.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


5 March-11 March 2014 Citation IconCite this Report

JMA reported that during 3-7 March six explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported explosions during 5-11 March. Plumes rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NE, E, SE, and S. Pilots observed ash drifting SE at an altitude of 2.1 km (7,000 ft) a.s.l. on 6 March, SE at an altitude of 3.7 km (12,000 ft) a.s.l. on 9 March, and NE at an altitude of 2.7 km (9,000 ft) a.s.l. on 11 March.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


26 February-4 March 2014 Citation IconCite this Report

JMA reported that during 24-28 February two explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. Incandescence from the crater was detected during 24-26 February. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported explosions during 27-28 February and 2-4 March. Plumes rose to altitudes of 1.2-4 km (4,000-13,000 ft) a.s.l. and drifted W, NW, NE, SE, and S during 28 February and 2-4 March. A pilot observed ash drifting at an altitude of 1.5 km (5,000 ft) a.s.l. on 2 March.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


19 February-25 February 2014 Citation IconCite this Report

JMA reported that during 17-21 February three explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that explosions during 19-20 and 22-25 February generated ash plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted NE, SE, and S. A pilot observed ash on 20 February.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


12 February-18 February 2014 Citation IconCite this Report

The Tokyo VAAC reported that explosions during 12-18 February from Aira Caldera’s Sakurajima volcano generated ash plumes on most days that rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. and drifted E, NE, and N. On 12 February a pilot observed an ash plume drifting E at an altitude of 3 km (10,000 ft) a.s.l. JMA reported that during 14-17 February two explosions from Showa Crater ejected tephra as far as 800 m. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


5 February-11 February 2014 Citation IconCite this Report

JMA reported that during 3-7 February five explosions from Sakurajima's Showa Crater ejected tephra as far as 1,300 m. Incandescence from the crater was detected at night. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported explosions during 6, 8-9, and 11 February. On 8 February a pilot observed an ash plume drifting at an altitude of 2.1 km (7,000 ft) a.s.l. Ash plumes rose to an altitude of 1.8 km (6,000 ft) a.s.l. on 9 February and 2.1 (7,000 ft) a.s.l. on 11 February.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


29 January-4 February 2014 Citation IconCite this Report

JMA reported that during 27-31 January five explosions from Sakurajima's Showa Crater ejected tephra as far as 1,300 m. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 29 January and during 31 January-2 February and on 4 February ash plumes rose to altitudes of 1.5-4.9 km (5,000-12,000 ft) a.s.l. and drifted N, NE, and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 January-28 January 2014 Citation IconCite this Report

JMA reported that during 20-24 January three explosions from Sakurajima's Showa Crater ejected tephra as far as 1,300 m. An explosion on 22 January generated a small pyroclastic flow that traveled 500 m SE, and tephrafall to the S. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that on 22 January a plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted S. That same day pilots observed ash plumes that rose to altitudes of 3.7-4.9 km (12,000-16,000 ft) a.s.l. and drifted S and ESE. On 24 January a pilot observed an ash plume drifting NE at an altitude of 1.2 km (4,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


15 January-21 January 2014 Citation IconCite this Report

The Tokyo VAAC reported that an explosion from Sakurajima on 17 January generated plumes that rose to altitude of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


8 January-14 January 2014 Citation IconCite this Report

JMA reported that during 6-10 January two explosions from Sakurajima's Showa Crater ejected tephra as far as 1,300 m. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that an explosion on 9 January generated a plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE. A pilot observed an ash plume drifting SE on 14 January.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


1 January-7 January 2014 Citation IconCite this Report

JMA reported that during 30 December 2013-6 January 2014 no explosions occurred from Sakura-jima's Showa Crater; weak incandescence from the crater was visible at night during 30-31 December. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that an explosion on 7 January generated a plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


18 December-24 December 2013 Citation IconCite this Report

JMA reported that on 19 December an explosion from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m. The Alert Level remained at 3 (on a scale of 1-5). The Tokyo VAAC reported that during 18-19 and 21-23 December explosions generated plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted E, SE, and S.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


11 December-17 December 2013 Citation IconCite this Report

The Tokyo VAAC reported that during 11-17 December explosions at Sakura-jima generated plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted E, SE, and S. JMA reported that six explosions from Showa Crater ejected tephra as far as 1,800 m during 13-16 December. A six-minute-long explosion was detected on 14 December. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


4 December-10 December 2013 Citation IconCite this Report

The Tokyo VAAC reported that during 4-8 December explosions at Sakura-jima generated plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted E and SE. JMA reported that six explosions from Showa Crater ejected tephra as far as 1,300 m during 6-9 December. Incandescence from the crater was occasionally detected. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


27 November-3 December 2013 Citation IconCite this Report

JMA reported that three explosions from Sakura-jima's Showa Crater ejected tephra as far as 800 m during 29 November-2 December. On 29 November an explosion ejected tephra, up to 1 cm in diameter, 4 km away. The Alert Level remained at 3 (on a scale of 1-5).The Tokyo VAAC reported that during 29-30 November, and 1 and 4 December, explosions generated plumes that rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted E and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


20 November-26 November 2013 Citation IconCite this Report

JMA reported that five explosions from Sakura-jima's Showa Crater ejected tephra as far as 800 m during 18-22 November. Incandescence was occasionally detected by a high resolution camera at night. A very small eruption from Minami-dake Crater occurred on 22 November, producing an ash plume that rose 100 m. The Alert Level remained at 3 (on a scale of 1-5).

The Tokyo VAAC reported that during 20-21 and 23-26 November, explosions generated plumes that rose to altitudes of 1.2-4.9 km (4,000-16,000 ft) a.s.l. and drifted N, E, and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


6 November-12 November 2013 Citation IconCite this Report

The Tokyo VAAC reported that during 6-8 and 10-11 November, explosions from Sakura-jima generated plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted N, NE, E, and SE. On 8 November a pilot observed an ash plume drifting at an altitude of 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 October-5 November 2013 Citation IconCite this Report

The Tokyo VAAC reported that during 30 October-5 November, explosions from Sakura-jima generated plumes that rose to altitudes of 1.5 km (5,000 ft) and 3.4 km (11,000 ft) a.s.l. Plumes rose vertically or drifted N, NW, NE, S, SW, and SE.

JMA reported that seven explosions from Showa Crater ejected tephra as far as 1,800 m during 1-5 November. On 4 and 5 November, incandescence was detected by a high resolution camera at night. The Alert Level remained at 3 (on a scale of 1-5).

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


23 October-29 October 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 24-29 October explosions from Sakura-jima generated plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. Plumes rose vertically or drifted N, NW, S, and SE. On 29 October a pilot observed an ash plume drifting SE at an altitude of 2.1 km (7,000 ft) a.s.l.

JMA reported that 11 explosions from Showa Crater ejected tephra as far as 1,800 m during 25-28 October. Explosions on 28 and 29 October generated ash plumes that rose to altitude of 3.2-3.5 km (10,500-11,500 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


16 October-22 October 2013 Citation IconCite this Report

JMA reported that seven explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m during 15-18 October. An explosion on 15 October was followed by 3-cm-sized tephra falling in areas 3.5 km SW. Based on information from JMA, the Tokyo VAAC reported that during 16-22 October explosions generated plumes that rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted W, SW, S, and SE. On 21 October an ash plume rose vertically to an altitude of 5.5 km (18,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


18 September-24 September 2013 Citation IconCite this Report

JMA reported that 18 explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m during 17-20 September. Incandescence from the crater was visible some nights. Based on information from JMA and pilot observations, the Tokyo VAAC reported that during 18-20 and 22-23 September explosions generated plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l., and drifted SW, W, and NW.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


11 September-17 September 2013 Citation IconCite this Report

JMA reported that 16 explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m during 9-13 September. Incandescence from the crater was visible some nights. An explosion at 1326 on 12 September generated an ash plume that rose 3.3 km.

Based on information from JMA, the Tokyo VAAC reported that during 11-18 September explosions generated plumes that rose to altitudes of 1.8-4.3 km (6,000-14,000 ft) a.s.l., and drifted in multiple directions on most days. On 12 and 14 September pilots observed ash plumes that rose to an altitude of 4 km (13,000 ft) a.s.l., and drifted SE and W, respectively.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


4 September-10 September 2013 Citation IconCite this Report

JMA reported that 15 explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m during 2-6 September. Incandescence from the crater was visible some nights. An explosion at 1100 on 4 September generated an ash plume that rose 2.8 km and drifted S, causing ashfall in areas downwind including Arimuracho (4 km SSE). Tephra 4 cm in diameter was confirmed in an area 3 km S, and tephra 1 cm in diameter was reported 10 km SSE.

Based on information from JMA, the Tokyo VAAC reported that during 4-10 September explosions generated plumes that rose to altitudes of 2.4-4.3 km (8,000-14,000 ft) a.s.l., and most days drifted N, NE, E, S, and SW. On 6 and 8 September pilots observed ash plumes that rose to altitudes of 3-4.6 km (15,000 ft) a.s.l.; plumes drifted NE on 8 September.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


28 August-3 September 2013 Citation IconCite this Report

JMA reported that 34 explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m during 26-30 August. Incandescence from the crater was visible at night on 26 August. An explosion on 29 August at 0927 generated an ash plume that rose 3 km and caused ashfall in areas from Miyazaki (80 km NW) to Kagoshima (12 km W). Tephra 1 cm in diameter was confirmed in an area 4 km E.

Based on information from JMA, the Tokyo VAAC reported that during 28 August-3 September explosions generated plumes most days that rose to altitudes of 1.5-4 km (5,000-13,000 ft) a.s.l. and drifted E, NE, and NW. On 31 August a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and traveled NE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


21 August-27 August 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-27 August explosions from Sakura-jima generated plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted in multiple directions. During 24 and 26-27 August pilots observed ash plumes that rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. and traveled SE and E. JMA reported that six explosions from Showa Crater during 23-26 August ejected tephra as far as 1,300 m. Incandescence from the crater was visible during 25-26 August.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


14 August-20 August 2013 Citation IconCite this Report

JMA reported that 24 explosions at Sakura-jima's Showa Crater were detected during 12-19 August and ejected tephra as far as 1.8 km. Incandescence from the crater was observed on 14 August. A very small eruption from Minami-dake Crater occurred on 16 August, producing an ash plume that rose 200 m.

An explosion from Showa Crater on 18 August generated a large ash plume that rose 5 km above the crater and drifted NW. A small pyroclastic flow traveled SE. According to news sources, the 50-minute-long eruption produced ashfall in the central and northern parts of Kagoshima (10 km W), causing train delays and poor visibility for car drivers. The event was the 500th explosion this year.

Sources: Japan Meteorological Agency (JMA); Agence France-Presse (AFP)


7 August-13 August 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 7-11 and 13 August explosions from Sakura-jima generated plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted SE, S, and NW. On 8, 10 and 13 August pilots observed ash plumes that rose to altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l., and traveled SE, S, and vertically, respectively. JMA reported that seven explosions at Showa Crater were detected during 9-12 August and ejected tephra as far as 800 m. A 50-minute-long eruption on 9 August generated an ash plume that rose 3.5 km above the crater.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


31 July-6 August 2013 Citation IconCite this Report

JMA reported that 10 explosions at Sakura-jima's Showa Crater were detected during 29 July-2 August and ejected tephra as far as 1.3 km. Incandescence from the crater was observed on 1 August. Based on information from JMA, the Tokyo VAAC reported that during 31 July-6 August explosions generated plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted E, SE, and S. On 31 July and 4 August pilots observed ash plumes that rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. and drifted E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


24 July-30 July 2013 Citation IconCite this Report

JMA reported that 10 explosions at Sakura-jima's Showa Crater were detected during 22-26 July, and ejected tephra as far as 1.3 km. Explosions at 1635 and 2333 on 22 July generated ash plumes that rose 3.2 and 3 km above the crater rim, respectively. Based on information from JMA, the Tokyo VAAC reported that during 24-30 July explosions generated plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E and SE. During 24-27 and 29 July pilots observed ash plumes that rose to altitudes of 2.7-5.5 km (9,000-18,000 ft) a.s.l. and drifted E and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


17 July-23 July 2013 Citation IconCite this Report

JMA reported that five explosions at Sakura-jima's Showa Crater were detected during 16-19 July, and ejected tephra as far as 1.3 km. A large plume rose 3.5 km above the crater on 16 July. Incandescence from the crater was observed at night during 18-19 July. Based on information from JMA, the Tokyo VAAC reported that during 18-21 July explosions generated plumes that rose to altitudes of 2.4-4.3 km (8,000-14,000 ft) a.s.l. and drifted N, E, SE, and S. Ash was sometimes detected in satellite images. On 19 July a pilot observed an ash plume that rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


10 July-16 July 2013 Citation IconCite this Report

JMA reported that 17 explosions at Sakura-jima's Showa Crater were detected during 8-15 July; incandescence from the crater was occasionally observed at night. Explosions during 10-11 July generated ash plumes that rose 3-3.4 km above the crater. Based on information from JMA, the Tokyo VAAC reported that during 10-16 July explosions generated plumes that rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l. and drifted N, NE, ENE, and E. Ash was detected in satellite images. During 10 and 14-15 July pilots observed ash plumes that rose to altitudes of 1.5-4 km (5,000-13,000 ft) a.s.l. and drifted NE and E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


3 July-9 July 2013 Citation IconCite this Report

JMA reported that two explosions at Sakura-jima's Showa Crater were detected during 5-8 July; cloud cover prevented visual observations of the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that during 8-9 July explosions generated plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted NE, E, and SE.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


26 June-2 July 2013 Citation IconCite this Report

JMA reported that during 25-28 June Sakura-jima's Showa Crater had four explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that on 26 June explosions were detected. Explosions on 1 July generated plumes that rose over 1.2 km (4,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


19 June-25 June 2013 Citation IconCite this Report

JMA reported that during 21-24 June Sakura-jima's Showa Crater had five explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that on 20 June explosions were detected, and on 21 June a pilot observed ash. On 23 and 25 June explosions produced plumes that rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted E and SE. On 23 June a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


12 June-18 June 2013 Citation IconCite this Report

JMA reported that during 10-14 June Sakura-jima's Showa Crater had four explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. One of the explosions on 13 June generated an ash plume that rose 3.3 km above the crater rim. Based on information from JMA, the Tokyo VAAC reported that on 16 June plumes rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


29 May-4 June 2013 Citation IconCite this Report

JMA reported that during 27-31 May Sakura-jima's Showa Crater had four explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. A small pyroclastic flow traveled 700 m down the E flank. A pyroclastic flow also occurred in the crater. Based on information from JMA, the Tokyo VAAC reported that on 30 May explosions produced plumes that rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted E. An explosion was detected on 1 June, and on 2 June an explosion produced an ash plume that rose 1.5 km (5,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


22 May-28 May 2013 Citation IconCite this Report

JMA reported that during 20-24 May Sakura-jima's Showa Crater had eight explosions, ejecting tephra that fell at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that during 23-26 May explosions produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted E, SW, and W. On 24 May a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Sources: Japan Meteorological Agency (JMA); Toulouse Volcanic Ash Advisory Centre (VAAC)


15 May-21 May 2013 Citation IconCite this Report

JMA reported that during 13-17 May Sakura-jima's Showa Crater had 13 explosions ejecting tephra that fell at most 1.8 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that during 15, 17-18, and 20-21 May explosions produced plumes that rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted E and W. On 21 May a pilot observed an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


8 May-14 May 2013 Citation IconCite this Report

JMA reported that during 7-10 May eight explosions from Sakura-jima's Showa Crater ejected tephra that fell at most 1.8 km from the crater. Crater incandescence was occasionally detected at night. Based on information from JMA, the Tokyo VAAC reported that on most days during 8-14 May explosions produced plumes that rose to altitudes of 2.1-4.3 km (7,000-14,000 ft) a.s.l. and drifted in multiple directions. During 9 and 13-14 May pilots observed ash plumes rising to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. and drifting N, NW, and W.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


1 May-7 May 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 1-6 April explosions from Sakura-jima generated ash plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted E and SE. A pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. on 3 April. Another ash plume observed by a pilot rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted S on 5 May.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 April-30 April 2013 Citation IconCite this Report

JMA reported that during 22-25 April four explosions from Sakura-jima's Showa Crater ejected tephra at most 1.3 km from the crater. Crater incandescence was occasionally detected at night. Based on a pilot report, the Tokyo VAAC reported that ash plumes drifted NE and SE at altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. during 24-25 April. Explosions on 26 and during 28-29 April produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted SE and NE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


17 April-23 April 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 17 April an eruption from Sakura-jima produced an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted E. JMA reported that three large eruptions from Showa Crater occurred during 19-22 April and ejected tephra at most 1.3 km from the crater. Crater incandescence was detected at night.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


10 April-16 April 2013 Citation IconCite this Report

JMA reported that occasional very small eruptions from Sakura-jima's Showa Crater occurred during 8-12 April. Crater incandescence was detected at night. Based on information from JMA, the Tokyo VAAC reported that on 13 April an eruption produced an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


3 April-9 April 2013 Citation IconCite this Report

JMA reported that during 1-5 April three explosions from Sakura-jima's Showa Crater ejected tephra at most 1.8 km from the crater. Crater incandescence was occasionally detected at night. Based on a pilot report, the Tokyo VAAC reported that an ash plume drifted N on 4 April.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


27 March-2 April 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 28 March-1 April generated plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted NE, E, and SE. JMA reported that during 29 March-1 April four explosions from Showa Crater ejected tephra at most 1.3 km from the crater.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


20 March-26 March 2013 Citation IconCite this Report

JMA reported that during 18-22 March nine explosions from Sakura-jima's Showa Crater were detected and ejected tephra fell at most 1.3 km from the crater.

Based on information from JMA, the Tokyo VAAC reported that explosions during 20-22 and 25 March generated ash plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted NE, E, and SE. A pilot observed an ash plume that drifted E at an altitude of 2.7 km (9,000 ft) a.s.l. on 20 March.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


13 March-19 March 2013 Citation IconCite this Report

JMA reported that 16 explosions from Sakura-jima's Showa Crater were detected during 11-15 March, ejecting tephra that fell at most 1.8 km from the crater. Crater incandescence was detected at night.

Based on information from JMA, the Tokyo VAAC reported that explosions during 13 and 15-19 March generated ash plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE, E, NE, and N. On 15 and 17 March pilots observed ash plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


6 March-12 March 2013 Citation IconCite this Report

JMA reported that nine explosions from Sakura-jima's Showa Crater were detected during 4-8 March, and ejected tephra fell at most 1.3 km from the crater. Crater incandescence was clearly detected at night.

Based on information from JMA, the Tokyo VAAC reported that explosions during 6-12 March generated plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE, E, and NE. Pilots observed ash plumes that rose to altitudes of 1.2-4.6 km (4,000-15,000 ft) a.s.l. during 7-11 March and drifted S and E.

Sources: Japan Meteorological Agency (JMA); Tokyo Volcanic Ash Advisory Center (VAAC)


27 February-5 March 2013 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 27 February-3 March and 5 March generated ash plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted S, SE, and E. A pilot observed an ash plume that rose to an altitude of 4.3 km (14,000 ft) a.s.l. on 28 February. JMA reported that 10 explosions from Showa Crater were detected during 1-4 March, and ejected tephra fell at most 1.3 km from the crater.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


20 February-26 February 2013 Citation IconCite this Report

JMA reported that 13 explosions from Sakura-jima's Showa Crater were detected during 18-22 February, and ejected tephra fell at most 1.3 km from the crater. Crater incandescence was clearly detected at night.

Based on information from JMA, explosions from Showa Crater during 20-26 February generated ash plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted SE, E, and NE. According to the Tokyo VAAC, a pilot observed an ash plume that drifted ENE at an altitude of 2.1 km (7,000 ft) a.s.l. on 25 February.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


13 February-19 February 2013 Citation IconCite this Report

JMA reported that during 12-15 February 16 explosions from Sakura-jima's Showa Crater were detected and ejected tephra fell at most 1.3 km from the crater. Crater incandescence was clearly detected at night.

Based on information from JMA, explosions from Sakura-jima's Showa Crater during 13-18 February generated plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted in multiple directions. The Tokyo VAAC reported that pilots observed ash plumes at altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. during 13 and 15-16 February.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


6 February-12 February 2013 Citation IconCite this Report

Based on information from JMA, explosions from Sakura-jima's Showa Crater during 6-12 February generated plumes that rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted SW, S, SE, E, and NE. The Tokyo VAAC reported that pilots observed ash plumes at altitudes of 2.4-3.4 km (8,000-11,000 ft) a.s.l. on 8 and 11 February.

JMA reported that during 8-12 February 34 explosions from Showa Crater were detected and ejected tephra fell at most 1.8 km from the crater. Crater incandescence was clearly detected at night.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


30 January-5 February 2013 Citation IconCite this Report

JMA reported that during 28 January-1 February explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Crater incandescence was occasionally detected.

The Tokyo VAAC reported that pilots observed ash plumes at altitudes of 3 km (10,000 ft) a.s.l. during 30-31 January. Based on information from JMA, explosions during 31 January-5 February generated plumes on most days that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted N, NW, and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


23 January-29 January 2013 Citation IconCite this Report

JMA reported that during 21-25 January explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Crater incandescence was detected on 21 January.

Based on information from JMA, the Tokyo VAAC reported that explosions during 23-29 January generated plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted E and SE. Pilots observed ash plumes drifting SE at altitudes of 3 and 2.4 km (10,000 and 8,000 ft) a.s.l. on 27 and 28 January, respectively.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


16 January-22 January 2013 Citation IconCite this Report

JMA reported that during 15-18 January explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. A very small eruption occurred at Minami-dake Crater on 15 January.

Based on information from JMA, the Tokyo VAAC reported that explosions during 16-21 January often generated plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted NE, E, SE, and S. A pilot reported that an ash plume drifted SE at an altitude of 2.4 km (8,000 ft) a.s.l. on 19 January.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


9 January-15 January 2013 Citation IconCite this Report

JMA reported that during 7-11 January explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Very small eruptions occurred at Minami-dake Crater during 10-11 January.

Based on information from JMA, the Tokyo VAAC reported that explosions during 9-15 January generated plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted N, NE, E, SE, and S. Pilots reported that ash plumes drifted E at an altitude of 1.8 km (6,000 ft) a.s.l. on 12 January and drifted SE at altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. on 15 January.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


2 January-8 January 2013 Citation IconCite this Report

JMA reported that during 28 December-4 January explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Very small eruptions occurred at Minami-dake Crater on 30 December and 4 January.

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 2 and 5-8 January generated plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted NE, E, and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


26 December-1 January 2013 Citation IconCite this Report

JMA reported that during 25-28 December explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. A small pyroclastic flow traveled 500 m E. Very small eruptions periodically occurred at Minami-dake Crater.

Source: Japan Meteorological Agency (JMA)


12 December-18 December 2012 Citation IconCite this Report

JMA reported that during 10-14 December explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Very small eruptions occurred at Minami-dake Crater periodically. Based on information from JMA, the Tokyo VAAC reported that explosions during 12-18 December often produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted N, NE, E, and SE. Pilots reported that ash plumes rose to an altitude of 2.1 km (7,000 ft) a.s.l. on 13 and 16 December.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


5 December-11 December 2012 Citation IconCite this Report

JMA reported that during 3-7 December explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. A very small eruption occurred at Minami-dake Crater on 6 December. Based on information from JMA, the Tokyo VAAC reported that explosions during 5-10 December often produced plumes that rose to altitudes of 1.2-4.3 km (4,000-14,000 ft) a.s.l. and drifted SW, S, SE, and E. A pilot reported that an ash plume drifted E at an altitude of 2.1 km (7,000 ft) a.s.l. on 7 December.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


28 November-4 December 2012 Citation IconCite this Report

JMA reported that during 26-30 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Very small eruptions at Minami-dake Crater occasionally occurred. Based on information from JMA, the Tokyo VAAC reported that explosions during 29 November-4 December produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted W, E, SE, and S. A pilot reported that an ash plume drifted SE at an altitude of 1.8 km (6,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


21 November-27 November 2012 Citation IconCite this Report

JMA reported that during 19-22 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Very small eruptions at Minami-dake Crater occurred during 19-20 November. Based on information from JMA, the Tokyo VAAC reported that explosions during 21-23, 25, and 27 November often produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted N, NE, E, and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


14 November-20 November 2012 Citation IconCite this Report

JMA reported that during 12-16 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Incandescence from Showa was observed during 12-13 November, and a very small eruption at Minami-dake Crater occurred on 16 November.

Based on information from JMA, the Tokyo VAAC reported that explosions during 14-20 November often produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted N, NE, E, and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


7 November-13 November 2012 Citation IconCite this Report

JMA reported that during 5-9 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Very small eruptions at Minami-dake Crater occurred during 8-9 November. Based on information from JMA, the Tokyo VAAC reported that explosions during 7-12 November produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted S, SE, and E. During 8-9 November pilots observed ash plumes that rose to altitudes of 2.4-4 km (8,000-13,000 ft) a.s.l. and drifted SE and E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


31 October-6 November 2012 Citation IconCite this Report

JMA reported that during 29 October-2 November explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. A small explosion from Minami-dake Crater occurred during 29-30 October. Based on information from JMA, the Tokyo VAAC reported that explosions during 2-5 and 7 November produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N, E, and SE. On 5 November a pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


24 October-30 October 2012 Citation IconCite this Report

JMA reported that explosions from Sakura-jima's Showa Crater during 15-29 October explosions ejected tephra as far as 1.8 km from the crater. A small explosion from Minami-dake Crater occurred on 29 October. Based on information from JMA, the Tokyo VAAC reported that explosions during 24-27 and 29-30 October produced plumes that rose to altitudes of 1.5-3.4 km (4,000-11,000 ft) a.s.l. and drifted N, NE, E, SE, and S. During 24-25 and 29 October pilots observed ash plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


17 October-23 October 2012 Citation IconCite this Report

JMA reported that explosions from Sakura-jima's Showa Crater during 15-19 October explosions ejected tephra as far as 1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported that explosions during 17-21 October produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted NE, E, and S. During 21-23 October pilots observed ash plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted N and SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


10 October-16 October 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima's Showa Crater during 12 and 14-15 October produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted W, SW, and SE. On 12 October a pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE. JMA reported that during 12-15 October explosions ejected tephra as far as 800 m from the crater.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


3 October-9 October 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima's Showa Crater during 3-9 October produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted W, SW, S, SE, and E. JMA reported that during 5-9 October explosions ejected tephra as far as 1.3 km from the crater. An explosion produced a small pyroclastic flow that traveled 300 m down the E side of Showa Crater.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


26 September-2 October 2012 Citation IconCite this Report

JMA reported that during 24-28 September explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.8 km from the crater. Based on information from JMA, the Tokyo VAAC reported that explosions during 26 September-2 October often produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted W, S, SE, and E. During 26-27 September pilots observed ash plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


19 September-25 September 2012 Citation IconCite this Report

JMA reported that during 15-21 September explosions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 19-20 and 22-24 September often produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. The plumes sometimes drifted NE, E, SE, S, and SW. On 19 September a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


12 September-18 September 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 13-15 and 17-18 September often produced plumes that rose to altitudes of 2.1-3.7 km (7,000-12,000 ft) a.s.l. The plumes sometimes drifted NW, N, and NE. On 14 September a pilot observed an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l.

Source: Japan Meteorological Agency (JMA)


5 September-11 September 2012 Citation IconCite this Report

JMA reported that during 3-7 September six explosive eruptions from Sakura-jima's Showa Crater ejected tephra as far as 1.3 km from the crater. Incandescence from the crater was observed at night. Based on information from JMA, the Tokyo VAAC reported that explosions during 6-11 September often produced plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. The plumes sometimes drifted N, NE, and SE. On 10 September a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


29 August-4 September 2012 Citation IconCite this Report

JMA reported that during 27-31 August five explosive eruptions from Sakura-jima's Showa Crater were detected and ejected tephra as far as 1.3 km from the crater. Gas measurements taken on 20 and 22 August showed elevated sulfur dioxide emissions compared to the previous week. Based on information from JMA, the Tokyo VAAC reported that explosions during 29-30 August and 1-4 September often produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. The plumes sometimes drifted N and NE. Pilots observed ash plumes during 1-2 September that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


22 August-28 August 2012 Citation IconCite this Report

JMA reported that during 20-24 August eight explosive eruptions from Sakura-jima's Showa Crater were detected and ejected tephra as far as 1.8 km from the crater. Gas measurements taken on 20 and 22 August showed elevated sulfur dioxide emissions compared to the previous week. Based on information from JMA, the Tokyo VAAC reported that explosions during 22-26 August produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted N, NW, and W. Explosions were detected on 28 August.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


15 August-21 August 2012 Citation IconCite this Report

JMA reported that during 17-20 August explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported that explosions during 17-21 August produced plumes that rose to altitudes of 2.4-3.4 km (8,000-11,000 ft) a.s.l. and drifted N and NW. Pilots observed ash plumes during 18-20 August that rose to altitudes of 2.1-4.3 km (7,000-14,000 ft) a.s.l. and drifted S, SW, and W.

According to a news report, the total amount of ash emitted from Sakura-jima from January to July was more than two times larger than all of 2011, when a record number of eruptions had occurred.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


8 August-14 August 2012 Citation IconCite this Report

JMA reported that during 6-10 August nine explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported that explosions during 8-14 August often produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted N and NE. A pilot observed an ash plume on 8 August.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


1 August-7 August 2012 Citation IconCite this Report

JMA reported that during 30 July-3 August three explosions from Sakura-jima's Showa Crater ejected tephra as far as 800 m from the crater. A small explosion from Minami-dake Crater occurred on 31 July. Based on information from JMA, the Tokyo VAAC reported that explosions during 1 and 3-7 July often produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted SW, W, and NW.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


25 July-31 July 2012 Citation IconCite this Report

JMA reported that during 24-27 July twenty explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m from the crater. An explosion on 26 July produced a large ash plume. Based on information from JMA, the Tokyo VAAC reported that explosions during 25-26 and 28-31 July produced plumes that rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. and drifted SW, W, NW, and N. Pilots observed ash plumes during 25-26 and 29 July that rose to altitudes of 2.4-3.4 km (8,000-11,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


18 July-24 July 2012 Citation IconCite this Report

JMA reported that during 20-23 July eight explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m from the crater. Incandescence from the crater was visible at night during 22-23 July. Based on information from JMA, the Tokyo VAAC reported that explosions during 18-24 July produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted in multiple directions. Pilots observed ash plumes on 22 and 24 July that rose to altitudes of 2.4-6.1 km (8,000-20,000 ft) a.s.l. JMA reported that an explosion on 24 July from Minami-dake Crater ejected tephra as far as 1,700 m from the crater.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


11 July-17 July 2012 Citation IconCite this Report

JMA reported that explosions from Sakura-jima's Showa Crater on 13, 15, and 17 July ejected tephra as far as 1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported that an explosion on 10 July produced an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted N. Explosions during 16-17 July produced plumes that rose to an altitude of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted NE, N, NW, and W.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


4 July-10 July 2012 Citation IconCite this Report

JMA reported that during 2-6 July explosions from Sakura-jima's Showa Crater ejected tephra as far as 1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported multiple explosions during 4-10 July; plumes rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E, SE, and N. A pilot observed an ash plume on 4 July that rose to an altitude of 2.4 (8,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


27 June-3 July 2012 Citation IconCite this Report

JMA reported that during 25-29 June large explosive eruptions from Sakura-jima's Showa Crater occurred ten times and ejected tephra as far as 1,300 m from the crater.

Based on information from JMA, the Tokyo VAAC reported multiple explosions during 27 June-1 July. The explosions sometimes produced plumes that rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted E, NE, and NW. A pilot observed an ash plume on 28 June that rose to an altitude of 1.8 (6,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


20 June-26 June 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 20 and 22 June explosions from Sakura-jima produced plumes that rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l. and drifted E. A pilot observed an ash plume on 20 June that rose to an altitude of 3.7 (12,000 ft) a.s.l. and drifted E. JMA reported that during 22-25 June large explosive eruptions from Showa Crater occurred five times and ejected tephra as far as 1,300 m from the crater. According to VAAC reports on 26 June, explosions were detected and an ash plume rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted W.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


13 June-19 June 2012 Citation IconCite this Report

JMA reported that during 11-15 June large explosive eruptions from Sakura-jima's Showa Crater occurred five times and ejected tephra as far as 800 m from the crater. A small eruption from Minami-dake Crater occurred on 13 June.

Based on information from JMA, the Tokyo VAAC reported that during 13-15 and 17-19 June explosions produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted multiple directions. A pilot observed an ash plume on 19 June that rose to an altitude of 3.4 (11,000 ft) a.s.l. and drifted E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


6 June-12 June 2012 Citation IconCite this Report

JMA reported that during 4-8 June explosive eruptions from Sakura-jima's Showa Crater occurred 11 times and ejected tephra as far as 1.3 km from the crater. A small pyroclastic flow traveled 200 m down the E flank.

Based on information from JMA, the Tokyo VAAC reported that during 6-7 and 9-11 June explosions produced plumes that rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted multiple directions. Pilots observed ash plumes during 6-7 June that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted S, E, and NE. Explosions were detected on 8 and 12 June.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


30 May-5 June 2012 Citation IconCite this Report

JMA reported that during 1-4 June seven explosions from Sakura-jima's Showa Crater ejected ballistics 800-1,300 m from the crater. Based on information from JMA, the Tokyo VAAC reported that during 30 May-5 June explosions produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted SW, W, and NW. Pilots observed ash plumes during 3-4 June that rose to altitudes of 2.7-3.4 (9,000-11,000 ft) a.s.l. and drifted W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 May-29 May 2012 Citation IconCite this Report

JMA reported eight explosive eruptions from Sakura-jima's Showa Crater during 21-25 May and a small eruption from Minami-dake Crater on 23 May. Based on information from JMA, the Tokyo VAAC reported that during 23-24 and 26-28 May explosions produced plumes that rose to altitudes of 1.8-4.6 km (6,000-15,000 ft) a.s.l. and drifted SW, S, SE, E, and NE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


16 May-22 May 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 16-20 and 22 May explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted multiple directions. Pilots observed ash plumes during 16-17 May that rose to altitudes of 2.7-4 km (9,000-13,000 ft) a.s.l. and drifted E and SE. Explosions were detected during 21-22 May.

JMA reported that during 18-21 May explosive eruptions from Showa Crater occurred multiple times and ejected tephra as far as 1.8 km from the crater. Incandescence from the crater was observed at night. Very small eruptions from Minami-dake Crater occurred on 18 and 19 May, and a small pyroclastic flow traveled 300 m down the Showa crater flanks on 21 May.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


9 May-15 May 2012 Citation IconCite this Report

JMA reported that during 11-15 May explosive eruptions from Sakura-jima's Showa Crater occurred nine times and ejected tephra as far as 1.3 km from the crater. Based on information from JMA, the Tokyo VAAC reported that during 9 and 11-15 May explosions produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted SW, S, SE, E, and N. A pilot observed an ash plume on 12 May that rose to an altitude of 2.1 (7,000 ft) a.s.l. and drifted E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


2 May-8 May 2012 Citation IconCite this Report

JMA reported that during 1-7 May explosive eruptions from Sakura-jima's Showa Crater occurred 17 times and ejected tephra as far as 1.3 km from the crater. Very small eruptions from Minami-dake Crater occurred on 3 and 5 May. Based on information from JMA, the Tokyo VAAC reported that during 3-4 and 6-8 May explosions produced plumes that rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. and drifted S, SE, and E. Ash was observed in satellite imagery on 3 May. A pilot observed an ash plume on 7 May that rose to an altitude of 2.4 (8,000 ft) a.s.l. and drifted SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


25 April-1 May 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 24 April-1 May explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted in multiple directions. A pilot observed an ash plume on 26 April that rose to an altitude of 2.7 (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 April-17 April 2012 Citation IconCite this Report

On 6, 8, and 10 April a visitor to Sakura-jima observed and photographed several Vulcanian explosions from Showa crater and noted that the crater was approximately 20% wider from N to S that in the beginning of 2010.

Source: Richard Roscoe, Photo Volcanica


21 March-27 March 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-22 March explosions from Sakura-jima produced ash plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted NE and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 March-20 March 2012 Citation IconCite this Report

JMA reported that on 12 March an explosion from Sakura-jima's Showa crater ejected tephra that landed as far as 2 km from the crater. Based on information from JMA, the Tokyo VAAC reported that during 14-21 March explosions often produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted N, NW, and SE. Pilots observed ash plumes during 18-20 March that rose to altitudes of 1.2-4 km (4,000-13,000 ft) a.s.l. and drifted SE and E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


7 March-13 March 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 7-9 and 11-13 March explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted E and SE. Pilots observed ash plumes during 9 and 11-13 March that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 February-6 March 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 29 February-7 March explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NW, E, and SE. A pilot observed an ash plume on 5 March. Another pilot report on 6 March noted a plume drifting SE at an altitude of 2.4 km (8,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 February-28 February 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 22 and 24 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


15 February-21 February 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 15-16 and 18-21 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


8 February-14 February 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 8-14 February explosions from Sakura-jima produced plumes that rose to altitudes of 1-3 km (3,000-10,000 ft) a.s.l. and drifted E and SE. On 11 February an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l., drifted E, and later dissipated. A pilot observation indicated an ash plume rising to an altitude of 1.8 km (6,000 ft) a.s.l. and drifting NE on 11 February.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 February-7 February 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 1-7 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.7 km (4,000-12,000 ft) a.s.l. and drifted E and SE. On 5 and 6 February pilots observed ash plumes that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and 3.7 km (12,000 ft) a.s.l. respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 January-31 January 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 25-27 and 29-30 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted E and SE. On 29 January a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 January-24 January 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 18-24 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted N, NE, E, and SE. On 20 January a pilot observed an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 January-17 January 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 11-17 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted NE, E, and SE. On 14 January a pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 January-10 January 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 4-10 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted NE, E, SE, and S. On 7 January an ash plume rose to an altitude 2.7 km (9,000 ft) a.s.l. and drifted SE, then later dissipated.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


28 December-3 January 2012 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 28 and 30 December-3 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted NE, E, SE, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 December-27 December 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-27 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted E, SE, S, and NE. Satellite imagery on 23 December showed ash emissions that later dissipated. On 27 December observations from satellite images and a pilot report showed an ash plume that rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 9 km E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 December-20 December 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 14-20 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted SE and S. On 15 December satellite imagery showed ash emissions that later dissipated. A pilot reported that an ash plume rose to an altitude of 1.5 km (5,000 ft) and drifted 32 km S on 18 December.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 December-13 December 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 7-13 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.0-2.7 km (3,000-9,000 ft) a.s.l. and drifted E, SE, S, and NE. Satellite imagery and a pilot report showed ash plumes that rose to an altitude of 2.4 km (8,000 ft) a.s.l and drifted 46 km SW on 9 December and 37 km S on 13 December.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 November-6 December 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 30 November and 2-6 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.0 km (4,000-10,000 ft) a.s.l. and drifted NE, E, SE, W, NW. Satellite imagery and a pilot report on 30 November showed an ash plume at an altitude 3.7 km (12,000 ft) a.s.l and drifted 37 km SE. On 5 December a pilot report and satellite imagery showed an ash plume at an altitude of 3.7 km (12,000 ft) a.s.l and drifted 74 km S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 November-29 November 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23 and 25-29 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted W, S, E, and NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 November-22 November 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 16-17 and 19-22 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted S, SE, E, and N. Satellite imagery on 16 and 21 November showed ash emissions that later dissipated. On 19 November a pilot reported an ash plume at an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 November-15 November 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 9-12 and 14-15 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted W, S, and SE. On 14 November a pilot reported that an ash plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE. Satellite imagery during 14-15 November showed ash emissions that later dissipated.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 November-8 November 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 2-3 and 5-7 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted W, NW, N, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


26 October-1 November 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 26 October-1 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted NW, W, SW, S, and SE. Satellite imagery on 26 October detected ash plumes that later dissipated. A pilot observed an ash plume on 31 October that rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 October-25 October 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 20-25 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted W, NW, E, and SE. Pilots observed ash plumes that rose to altitudes of 3 and 1.5 km (10,000 and 5,000 ft) a.s.l. on 23 and 25 October, respectively. The plumes drifted SE on both days.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


12 October-18 October 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 12-13 and 15-18 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted SE and E. On 18 October a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


5 October-11 October 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 5-11 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NW, N, SE, and S. During 6-8 October pilots observed ash plumes that rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


28 September-4 October 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 28 September-3 October explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted in multiple directions. On 30 September and during 1-2 October pilots observed ash plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and mostly drifted NE, E, and ESE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 September-27 September 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-27 September explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted SE, S, and W. On 22 September a pilot observed an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 September-20 September 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 14-20 September explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted S, SW, W, and NW. On 14 September a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 September-13 September 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 9-13 September explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted NW and N. On 9 September a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


31 August-6 September 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 31 August-6 September explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted SW, S, and SE. According to a news article, the 660th explosive eruption in 2010 occurred on 3 September. The article also noted that as of 2 September, 607 grams of ash per square meter had fallen in Kagoshima (10 km W), compared to 753 grams for all of 2010, when the volcano had a record-high 896 explosive eruptions.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); The Japan Times


24 August-30 August 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23-30 August explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted SW, W, NW, N, and NE. On 30 August a pilot observed an ash plume that rose to an altitude of 1.2 km (4,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


17 August-23 August 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 17-22 August explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted E. On 18 August, a pilot observed an ash plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


10 August-16 August 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 10-16 August explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. On 12 August, a pilot observed an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 August-9 August 2011 Citation IconCite this Report

The Tokyo VAAC reported that on 3 August an ash plume from Sakura-jima observed by a pilot rose to an altitude of 1.5 km (5,000 ft) a.s.l. Based on information from JMA, plumes rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted W, NW, and NE during 3 and 5-9 August.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


27 July-2 August 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 27 July-2 August plumes from Sakura-jima rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. During 28-30 July and 1 August, pilots observed ash plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. Plumes occasionally drifted SW, S, SE, and W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 July-26 July 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 20-22 and 25 July plumes from Sakura-jima rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. Plumes occasionally drifted S, SE, and ENE. On 20, 22, and 26 July, pilots observed ash plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 July-19 July 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 13-19 July plumes from Sakura-jima rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. Plumes occasionally drifted W, NW, and N. On 18 July, a pilot observed an ash plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. Explosions were reported the next day.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 July-12 July 2011 Citation IconCite this Report

According to pilot observations, the Tokyo VAAC reported that on 7 and 10 July ash plumes rose from Sakura-jima to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. Reports from JMA stated that plumes rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. on 8, 10, and 12 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 June-5 July 2011 Citation IconCite this Report

According to pilot observations, the Tokyo VAAC reported that ash plumes rose from Sakura-jima to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l on 28 and 30 July. Reports from JMA stated that plumes rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. during 30 June-1 July. An explosion was noted on 4 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 June-28 June 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 22, 25, and 28 June plumes from Sakura-jima rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N and NE. During 27-28 June, pilots observed ash plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


8 June-14 June 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 8-9 and 14 June explosions from Sakura-jima produced plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted E and SE. During 8-9 and 13-14 June, pilots observed ash plumes that rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 June-7 June 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 2-6 June explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. Plumes drifted S on 2 June. On 2 and 4 June, pilots observed ash plumes that rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 May-31 May 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 25-30 May explosions from Sakura-jima frequently produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. Plumes drifted N, NW, E, SE, and S. On 27 May, a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 May-24 May 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 18-22 May explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. Plumes drifted in multiple directions. On 21 May, a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 May-17 May 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 11-18 May explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. Plumes occasionally drifted SE and S. During 11, 13-14, and 17 May, pilots observed ash plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 May-10 May 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 6-10 May explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. Plumes sometimes drifted NW, NE, E, SE, and S. On 4 and 9 May, pilots observed ash plumes that rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


27 April-3 May 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 27-30 April and 2-3 May explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted N, NE, E, SE, and S. On 29 April and 2 May, pilots observed ash plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted S and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 April-26 April 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-25 April explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and occasionally drifted N, NE, E, and SE. On 21 and 25 April, pilots observed ash plumes that rose to altitudes of 2.7-3.4 km (9,000-11,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 April-19 April 2011 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that during 13-19 April explosions from Sakura-jima mostly generated ash plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted S, SE, and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 April-12 April 2011 Citation IconCite this Report

On 6, 9, and 12 April, pilots observed ash plumes from Sakura-jima that rose to altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. Plumes on 9 April drifted SE and plumes on 12 April drifted S. Based on information from JMA, the Tokyo VAAC reported that during 7-12 April explosions produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and occasionally drifted NE, E, SE, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 March-5 April 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 1 and 3-5 April explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-4 km (5,000-13,000 ft) a.s.l. and occasionally drifted E. A video of activity from 4 April showed incandescence emanating from the crater and a few explosions that ejected incandescent material onto the flanks. On 5 April, a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Sources: Volcano Sakura-jima; Tokyo Volcanic Ash Advisory Center (VAAC)


23 March-29 March 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23-26 and 29 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and occasionally drifted E, SE, and S. On 26 March, a pilot observed an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 March-22 March 2011 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that during 16-19 and 21-22 March explosions from Sakura-jima produced ash plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NE, E, and SE. Explosions were reported on 20 March.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 March-15 March 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 9-15 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.1 km (4,000-7,000 ft) a.s.l. and drifted NW, N, NE, E, and SE. On 12 March, a pilot reported that an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. Another ash plume also observed by a pilot rose to an altitude of 1.5 km (5,000 ft) a.s.l. on 15 March.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 March-8 March 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 2-5 and 8 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-1.8 km (4,000-6,000 ft) a.s.l. and drifted E, SE, and S. During 2-4 and 5 March, pilots reported that ash plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. Some plumes drifted N and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 February-1 March 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23 February-2 March explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted in multiple directions. On 23 and 26 February, pilots reported that ash plumes rose to altitudes of 3 and 4 km (10,000 and 13,000 ft) a.s.l. and drifted E and NW, respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 February-22 February 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 16-17 and 19-22 February explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. Some plumes drifted W, SW, and ESE. During 21-22 February, pilots reported that ash plumes rose to altitudes of 2.4-2.7 km (8,000-9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 February-15 February 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 9 and 11-15 February explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted S, SE, and E. On 10, 13, and 15 February, pilots reported that ash plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 February-8 February 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 1-8 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted SE, E, and NE. During 3-4 and 7 February, pilots reported that ash plumes rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. According to a news article, an eruption on 8 February produced a gas-and-ash plume that rose 2 km. A large amount of ashfall prompted local authorities to temporarily ban residents from driving near the area.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Arirang News


26 January-1 February 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 26 January-1 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted SE and E. On 31 January, a pilot reported that an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 January-25 January 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 19 and 21-23 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted SE and E. On 22 January, a pilot reported that an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


12 January-18 January 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 13 and 16-18 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted SE. On 17 January, a pilot reported that an ash plume rose to altitudes of 1.2-2.1 km (4,000-7,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


5 January-11 January 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 7-8 January explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E and SE. On 8 January, pilots reported that ash plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 December-4 January 2011 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 2 January a plume from Sakura-jima rose to an altitude of 1.8 km (6,000 ft) a.s.l. An explosion was noted the next day. An explosion on 5 January produced a plume that rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 December-28 December 2010 Citation IconCite this Report

Based on pilot observations, the Tokyo VAAC reported that during 22-23, 25, and 27 December ash plumes from Sakura-jima rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


15 December-21 December 2010 Citation IconCite this Report

Based on pilot observations, the Tokyo VAAC reported that on 18 December ash plumes from Sakura-jima rose to altitudes of 2.4-4.9 km (8,000-16,000 ft) a.s.l. and drifted SE. The next day satellite imagery showed that the ash had dissipated.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


8 December-14 December 2010 Citation IconCite this Report

Based on information from JMA and analysis of satellite imagery, the Tokyo VAAC reported that on 8 December an eruption from Sakura-jima produced an ash plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted E and SE. During 11-12 December explosions produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted SE and E. On 12 December a pilot observed an ash plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted NE and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 December-7 December 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 1-7 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted E, SE, W, NW, and N. During 2 and 4-5 December, pilots reported that ash plumes rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 November-30 November 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 24 November-1 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-1.8 km (4,000-6,000 ft) a.s.l. and drifted E, SE, and S. During 24 and 28-29 November, pilots reported that ash plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


17 November-23 November 2010 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that during 17, 19-21, and 23 November ash plumes from Sakura-jima rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted E, NE, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


10 November-16 November 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 10-16 November explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted E, SE, and S. During 15-16 November, pilots reported that ash plumes rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 November-9 November 2010 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that during 3-5 and 7-9 November explosions from Sakura-jima produced ash plumes that rose to altitudes of 1.5-4.3 km (5,000-14,000 ft) a.s.l. and drifted E, ESE, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


27 October-2 November 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption from Sakura-jima on 31 October produced a plume that rose to an altitude of 1.5 km (6,000 ft) a.s.l. and drifted NE. On 2 November a pilot reported that an ash plume rose to an altitude of 1.5 km (6,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 October-26 October 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 20 October.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 October-19 October 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 13-16 October produced plumes that rose to altitudes of 1.5-2.1 km (6,000-7,000 ft) a.s.l. and drifted NE, E, SE, and S. During 15-16 October pilots reported that ash plumes rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted E and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 October-12 October 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 7-10 October produced plumes that rose to altitudes of 1.5-2.1 km (6,000-7,000 ft) a.s.l. and drifted NW, NE, SE, and S. On 8 October a pilot reported that an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 September-5 October 2010 Citation IconCite this Report

Based on a pilot observation, the Tokyo VAAC reported that on 1 October an ash plume from Sakura-jima rose to an altitude of 1.8 km (6,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 September-28 September 2010 Citation IconCite this Report

Based on a pilot observation, the Tokyo VAAC reported that on 22 September an ash plume rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


15 September-21 September 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an eruption from Sakura-jima on 15 September. That same day a pilot observed an ash plume at an altitude of 3 km (10,000 ft) a.s.l. On 16 September a pilot reported that an ash plume rose to an altitude of 1.8 km (6,000 ft) and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


8 September-14 September 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 8 and 10 September produced plumes that rose to altitudes of 1.5-1.8 km (6,000-8,000 ft) a.s.l. Some of the plumes drifted E and NE. On 9 September a pilot reported that an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 September-7 September 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 1-5 September produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. Some of the plumes drifted N, NW, and W. During 2-4 September pilots reported that ash plumes rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. An explosion also occurred on 7 September.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 August-31 August 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 26-31 August produced plumes that rose to altitudes of 1.2-2.1 km (4,000-7,000 ft) a.s.l. Some of the plumes drifted N and NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 August-24 August 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 18, 21, and 23 August produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted W and NW. On 19 and 24 August pilots observed ash plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 August-10 August 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 4-9 August produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted W, NW, and N. Pilots observed ash plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. on 7, 9, and 10 August.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


28 July-3 August 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion on 29 July. Explosions during 31 July-1 August and 3 August produced plumes that rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E and SW. On 2 July a pilot observed an ash plume that rose to an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 July-27 July 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 21-27 July explosions from Sakura-jima produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.2-4.6 km (4,000-15,000 ft) a.s.l. Most plumes rose vertically while others drifted N and NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 July-20 July 2010 Citation IconCite this Report

Based on JMA notices, the Tokyo VAAC reported explosions from Sakura-jima on 14 and 20 July. During 15-18 July pilots observed ash plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted NE, N, and NW. Plumes on 20 July rose as high as 2.1 km (7,000 ft) a.s.l. and drifted NW and N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 July-13 July 2010 Citation IconCite this Report

Based on pilot observations, the Tokyo VAAC reported that on 7 and 9 July ash plumes from Sakura-jima rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted SE and NE. The VAAC also noted that the JMA reported explosions during 11-13 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 June-6 July 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 30 June-1 July and 4-6 July explosions from Sakura-jima sometimes produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l. and drifted E and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 June-29 June 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23-29 June explosions from Sakura-jima sometimes produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.8-3.7 km (6,000-12,000 ft) a.s.l. and drifted E, SE, and NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 June-22 June 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 16-22 June explosions from Sakura-jima sometimes produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. According to a news article, the JMA noted that two eruptions on 20 June brought the total number of eruptions in 2010 to 550, setting a new annual record. The total number of eruptions in 2009, the previous high at Sakura-jima, was 548.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); The Japan Times


9 June-15 June 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported explosions from Sakura-jima during 12-14 June. Details of possible resulting plumes were not reported. On 15 June an ash plume at an altitude of 3 km (10,000 ft) a.s.l. was reported by a pilot.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 June-8 June 2010 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that on 3 June an eruption from Sakura-jima produced a plume that rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. and drifted W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 May-25 May 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 21 May an explosion from Sakura-jima produced a plume that rose to an altitude higher than 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


12 May-18 May 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 14 May an explosion from Sakura-jima produced a plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


5 May-11 May 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 4-6 and 8-9 May explosions from Sakura-jima often produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 2.1-3.7 km (7,000-12,000 ft) a.s.l. and sometimes drifted N, NE, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


28 April-4 May 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 28 April-5 May explosions from Sakura-jima often produced plumes. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and sometimes drifted NE, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 April-27 April 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 14-26 April explosions from Sakura-jima sometimes produced plumes identified in satellite imagery. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.5-3.7 km (5,000-12,000 ft) a.s.l. and sometimes drifted in multiple directions.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 April-13 April 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 7-13 April explosions from Sakura-jima sometimes produced plumes identified in satellite imagery. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and sometimes drifted NW, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


31 March-6 April 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 31 March-6 April explosions from Sakura-jima sometimes produced plumes identified on satellite imagery. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SW, SE, E, and NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 March-30 March 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 24-30 March explosions from Sakura-jima sometimes produced plumes identified on satellite imagery. Those plumes, along with ash plumes occasionally seen by pilots, rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted SW, S, SE, and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


17 March-23 March 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 17-23 March plumes from Sakura-jima identified on satellite imagery, and ash plumes seen by pilots, rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted SE and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


10 March-16 March 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 10-16 March multiple explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted N, NE, E, and SE. Pilots reported that on 11 and 16 March ash plumes rose as high as 2.7 km (9,000 ft) a.s.l. and drifted SE and NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 March-9 March 2010 Citation IconCite this Report

During 3-9 March, the Tokyo VAAC reported multiple explosions from Sakura-jima based on information from JMA. During 3, 5-6, and 8-9 March, plumes rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted NE, E, and SE. Pilots reported on 8 and 9 March that ash plumes rose as high as 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 February-2 March 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 24 February-2 March explosions from Sakura-jima produced plumes identified in satellite imagery and seen by pilots. The plumes, occasionally containing ash, rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted N, NE, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


17 February-23 February 2010 Citation IconCite this Report

The Tokyo VAAC reported that during 17-23 February plumes from Sakura-jima identified on satellite imagery, and ash plumes seen by pilots, rose to altitudes of 1.5-4 km (5,000-13,000 ft) a.s.l. and drifted NE, E, SE, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


10 February-16 February 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 11-16 February multiple explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted N, E, SE, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 February-9 February 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 3-9 February multiple explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted SE and N. On 5, 6, and 7 February, pilots reported that ash plumes sometimes drifted SE and S at altitudes of 1.5-3.4 km (5,000-11,000 ft) a.s.l. An eruption on 8 February produced an estimated 1-km-high lava fountain, and an ash plume with abundant lightning. Incandescent material fell onto the flanks.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Kago-Net


27 January-2 February 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 27 January-2 February multiple explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted SE, E, and NE. During 27-29 January and 1-2 February, pilots reported that ash plumes sometimes drifted SE and S at altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 January-26 January 2010 Citation IconCite this Report

During 26 December 2009-9 January 2010, a visitor to Sakura-jima observed and photographed Strombolian and Vulcanian explosions from Showa crater. Based on information from JMA, the Tokyo VAAC reported that during 20-26 January multiple explosions often produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and drifted NE, E, SE, and S. On 23 January, a pilot reported that an ash plume drifted SE at an altitude of 1.8 km (6,000 ft) a.s.l.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Richard Roscoe, Photo Volcanica


13 January-19 January 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 13-19 January multiple explosions from Sakura-jima often produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted SE and E. On 16 and 18 January, pilots reported that ash plumes drifted SE at altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 January-12 January 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 6-12 January multiple explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted SE and E. On 10 January a pilot reported that an ash plume drifted SE at an altitude of 3 km (10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 December-5 January 2010 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 30 December-5 January multiple explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted NE, E, SE, and S. During 31 December-4 January pilots reported that ash plumes rose to altitudes of 2.4-5.5 km (8,000-18,000 ft) a.s.l. and drifted SE and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 December-29 December 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 23-29 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted E, SE, and S. During 23-25 and 27 December, pilots reported that ash plumes rose to altitudes of 2.7-4.6 km (9,000-15,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 December-22 December 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 16-17 and 20-22 December explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted E, SE, and S. On 19 and 22 December, pilots reported that ash plumes rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 December-15 December 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 9-15 December produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, SE, and S. On 14 December, a pilot reported that an ash plume drifted S at an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 December-8 December 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 2-8 December produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted in multiple directions. On 4 and 8 December, pilots 30-65 km S of Kagoshima airport reported ash plumes that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SW and NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 November-1 December 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 26 November and 1 December produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted SW and E. Ash was seen in satellite imagery on 26 November.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 November-24 November 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 18 and 23 November produced plumes that rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted S and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 November-17 November 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 11-13 and 15-17 November produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted in multiple directions.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 November-10 November 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 4-10 November produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted in multiple directions. Pilots reported ash plumes that rose to an altitude of 2.4 km (8,000 ft) a.s.l. on 5 November and to an altitude of 1.2 km (4,000 ft) a.s.l. on 9 November. Plumes drifted E and N, respectively. According to a news article, Sakura-jima exploded for the 400 th time in 2009 on 5 November.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); The Japan Times


28 October-3 November 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 28 October-3 November produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. Some plumes drifted W, SW, S, SE, and NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 October-27 October 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 21-22, 24-25, and 27-28 October produced plumes that rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. Some plumes drifted W, SW, S, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 October-20 October 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 13-20 October produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted SW, S, SE, and E. On 15 October, a pilot reported that an ash plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 October-13 October 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 7-12 October produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted W, SW, S, and SE. An explosion was also detected on 13 October.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 September-6 October 2009 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that explosions from Sakura-jima during 30 September-6 October produced plumes that rose to altitudes of 1.8-4.3 km (6,000-14,000 ft) a.s.l. Plumes occasionally drifted E, N, and W.

The JMA reported that explosions from Showa crater on 2 October ejected incandescent tephra 800 m away from the rim. On 3 October, Minami-dake crater exploded violently, producing an ash plume that rose 3 km above the crater. Ballistics were ejected 1.7 km away. The most recent previous explosion from the Minami-dake crater occurred on 22 February.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


23 September-29 September 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 23, 25, and 27-29 September produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. and drifted SW, W, and NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 September-22 September 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 16, 18-19, and 21 September produced plumes that rose to altitudes of 1.5-2.7 km (7,000-8,000 ft) a.s.l. and drifted S, SW, W, NW, and NE. A pilot reported ash on 19 September.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 September-15 September 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 9-15 September produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted S, SE, and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 September-8 September 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 2-8 September produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted W, SW, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


26 August-1 September 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 26-29 August and 1 September produced plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. Plumes occasionally drifted N, NE, and E. An explosion was reported on 31 August but no information about a possible resulting plume was reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 August-25 August 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 19-25 August produced plumes that rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. Plumes occasionally drifted N, E, and SE. A pilot reported that on 24 August an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted less than 20 km S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


12 August-18 August 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported eruptions and explosions from Sakura-jima during 12-17 August. Plumes rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. during 14-17 August and occasionally drifted E or N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


5 August-11 August 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruptions and explosions from Sakura-jima during 5-10 August produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. Pilots reported that ash plumes rose to altitudes of 1.8-4 km (6,000-13,000 ft) a.s.l. during 7 and 9-10 August. Plumes drifted in multiple directions.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 July-4 August 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported explosions from Sakura-jima during 31 July-4 August. Plumes rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. on all days except 1 August.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 July-28 July 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 22 July explosions from Sakura-jima produced plumes that rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted E and SE. On 23 July and 27 July pilots observed ash plumes that rose to altitudes of 2.1 and 3 km (7,000 and 10,000 ft) a.s.l. and drifted E and SW, respectively. Explosions were reported during 24-25 and 28 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


15 July-21 July 2009 Citation IconCite this Report

Based on information from JMA, analyses of satellite imagery, and pilot observations, the Tokyo VAAC reported that during 15-21 July explosions from Sakura-jima's Showa crater occasionally produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. Plumes were observed drifting SW, N, and NE. On 19 July, JMA raised the Alert Level from 2 to 3 (on a scale of 1-5). They noted increased frequency of explosive eruptions since late June, and shock waves that were detected on 18 and 19 July.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


8 July-14 July 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 8 and 10-15 July explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. The plumes drifted NE and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 July-7 July 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 2-4 and 6-7 July explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. The plumes drifted N, NE, E, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 June-30 June 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 24-30 June explosions from Sakura-jima sometimes produced plumes that rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. The plumes drifted NE, E, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


10 June-16 June 2009 Citation IconCite this Report

Based on a pilot observation, the Tokyo VAAC reported that on 12 June an ash plume from Sakura-jima rose to an altitude of 1.8 km (6,000 ft) a.s.l. The JMA reported that during 14-16 June eruptions produced plumes that rose to altitudes of 2.4-2.7 km (8,000-9,000 ft) a.s.l. Plumes drifted SE and E on 14 and 15 June.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 June-9 June 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 7 June an eruption from Sakura-jima produced a plume that rose vertically to an altitude of 3 km (10,000 ft) a.s.l. An eruption on 9 June resulted in a plume that rose to an attitude of 2.4 km (8,000 ft) a.s.l. and drifted N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


27 May-2 June 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 30 May an explosion from Sakura-jima produced a plume that rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted SE. On 31 May, an ash plume rose to an altitude of 3 km (10,000 ft) a.s.l. The next day, eruptions produced plumes that rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. Some plumes drifted S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 May-26 May 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 26 May an eruption from Sakura-jima produced a plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 May-19 May 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 19 May an eruption from Sakura-jima produced a plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 May-12 May 2009 Citation IconCite this Report

Based on information from JMA and pilot observations, the Tokyo VAAC reported that on 9 May eruptions from Sakura-jima produced plumes that rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted S. On 12 May, an ash plume drifted E at an altitude of 1.8 km (6,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


29 April-5 May 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 3-4 May eruptions from Sakura-jima produced plumes that rose to altitudes of 2.4-3.7 km (8,000-12,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 April-28 April 2009 Citation IconCite this Report

On 24 April, JMA lowered the Alert Level for Sakura-jima from 3 to 2 (on a scale of 1-5). No large eruptions occurred after 11 April, seismicity was low, and deformation was not detected.

Source: Japan Meteorological Agency (JMA)


8 April-14 April 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 8 April an eruption from Sakura-jima produced a plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. JMA reported that on 9 April a Vulcanian explosion from Showa crater on the E flank ejected bombs as far away as 1.3 km. A plume rose to an altitude of 4.8 km (15,700 ft) a.s.l. and drifted SW; JMA stated that the plume altitude was the highest altitude a plume reached since June 2006. A pyroclastic flow traveled 1 km E. According to a news article, heavy ashfall was reported in Kagoshima City (about 10 km W), the first ashfall reported there since October 2002. On 10 April, the Tokyo VAAC reported that eruptions produced plumes that rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted W and S.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Asahi; Japan Meteorological Agency (JMA)


1 April-7 April 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 5-7 April explosions and eruptions from Sakura-jima produced plumes that rose to altitude of 2.1-3 km (7,000-10,000 ft) a.s.l. Plumes drifted SE on 5 April and S on 7 April.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 March-31 March 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion from Sakura-jima on 26 March produced a plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SE. JMA reported occasional weak eruptions during 27-30 March.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


18 March-24 March 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported explosions from Sakura-jima on 20 and 23 March. Additional information on possible resultant plumes was not reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 March-17 March 2009 Citation IconCite this Report

On 14 March, JMA reported two Vulcanian explosions from Sakura-jima to heights of 400-500 m above an unspecified crater; ejected bombs landed as far away as 800 m. Both the summit crater and Showa crater on the E flank had recently been active. Based on information from JMA, the Tokyo VAAC reported that an eruption on 17 March produced a plume that rose to an altitude of 2.1 km (6,000 ft) a.s.l. and drifted E.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


4 March-10 March 2009 Citation IconCite this Report

During 7-10 March, JMA reported that 12 Vulcanian explosions occurred from Showa Crater, on the E flank of Sakura-jima. Some explosions were seen from JMA's Kagoshima Observatory; observers reported that ejected bombs landed as far away as 800 m from the crater and plumes rose to an altitude of 2.9 km (9,500 ft) a.s.l. Based on information from JMA, the Tokyo VAAC reported that an eruption on 7 March, and explosions during 8-10 March, produced plumes that rose to altitudes of 1.8-2.7 km (6,000-9,000 ft) a.s.l. Plumes drifted N and S during 8-10 March. [Correction: Ejected bombs landed as far away as 1,800 m from the crater.]

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


25 February-3 March 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported explosions from Sakura-jima during 28 February-1 March. On 1 March, plumes rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted S. JMA raised the Alert Level from 2 to 3 (on a scale of 1-5). During 1-2 March, three Vulcanian explosions occurred from Showa Crater, ejecting bombs that landed as far away as 1.3 km on 2 March. Deformation was also detected. The Tokyo VAAC reported that eruptions or explosions produced plumes that rose to altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. on 2 and 4 March, and an explosion occurred on 3 March.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


18 February-24 February 2009 Citation IconCite this Report

JMA lowered the Alert Level for Sakura-jima from 3 to 2 (on a scale of 1-5) on 19 February because deformation was absent, seismicity was low, and no eruptions occurred after 5 February. Based on information from JMA, the Tokyo VAAC reported that on 22 February an explosion produced a plume that rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted N.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


11 February-17 February 2009 Citation IconCite this Report

Based on analysis of satellite imagery and pilot observations, the Tokyo VAAC reported that during 11-12 February ash plumes from Sakura-jima rose to altitudes of 1.2-1.5 km (4,000-5,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 February-10 February 2009 Citation IconCite this Report

JMA reported that Sakura-jima erupted explosively eight times during 1-2 February; bombs were deposited as far away as 800 m from the Showa crater (on the E slope of Minami-dake, or "south mountain," at an elevation of about 800 m). JMA raised the Alert Level from 2 to 3 on 2 February. Based on information from JMA, the Tokyo VAAC reported that during 4-5 February explosions and eruptions produced plumes that rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted SE. On 9 February a pilot reported that an ash plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Japan Meteorological Agency (JMA)


28 January-3 February 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 28 January and 1-3 February explosions and eruptions from Sakura-jima produced plumes that rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted SE, S, and SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 January-20 January 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 15 January an explosion from Sakura-jima produced a plume that rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 January-13 January 2009 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 9 January an eruption from Sakura-jima produced a plume that rose to an altitude of more than 2.4 km (8,000 ft) a.s.l. and drifted SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 October-7 October 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 3 October an eruption plume from Sakura-jima rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 September-9 September 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 7 September an eruption plume from Sakura-jima rose straight up to an altitude greater than 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 August-26 August 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 23 August. The altitude and direction of a possible resultant plume were not reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 August-12 August 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 10 August an eruption plume from Sakura-jima rose to an altitude greater than 2.7 km (9,000 ft) a.s.l. and drifted NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 July-29 July 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 25-28 July ash plumes from Sakura-jima rose to altitudes of 2.4-4.3 km (8,000-14,000 ft) a.s.l. and drifted N, NE, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 July-15 July 2008 Citation IconCite this Report

Based on information from JMA and satellite data, the Tokyo VAAC reported ash plumes from Sakura-jima on 10 and 13 July that rose to an altitude of 2.7 km (9,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 July-8 July 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 5 July. A resultant plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 June-1 July 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 28 June. The altitude and direction of a possible resultant plume were not reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


11 June-17 June 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 12-13 June explosions from Sakura-jima produced ash plumes to an altitude of 3.4 km (11,000 ft) a.s.l. The plumes drifted NW, NE, and SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 June-10 June 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 9 June eruption plumes from Sakura-jima rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted S. Explosions were reported on 10 and 11 June.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


28 May-3 June 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 30 May-1 June eruption plumes from Sakura-jima rose to altitudes of 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted NW, NE, E, and S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 May-27 May 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 22 May an eruption plume from Sakura-jima rose to altitudes of 2.4 km (8,000 ft) a.s.l. and drifted NE. An explosion was reported on 24 May.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 May-20 May 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that during 15-21 May eruption plumes from Sakura-jima rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. The plumes drifted N, NE, SE, S, and SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 May-13 May 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 8 May an eruption plume from Sakura-jima rose to an altitude of 4 km (13,000 ft) a.s.l. The plume drifted E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 April-6 May 2008 Citation IconCite this Report

Based on information from JMA and observations of satellite imagery, the Tokyo VAAC reported that during 6-7 May eruption plumes from Sakura-jima rose to altitudes of 2.4-3.4 km (8,000-11,000 ft) a.s.l. The plumes drifted S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 April-29 April 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruption plumes from Sakura-jima rose to an altitude of 2.4 km (8,000 ft) a.s.l. The plumes drifted SE on 27 April and W on 30 April.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 April-22 April 2008 Citation IconCite this Report

Based on pilot reports and observations of satellite imagery, the Tokyo VAAC reported that an ash plume from Sakura-jima rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted 100 km E on 19 April. The next day, the JMA reported that a plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 April-15 April 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima during 11-15 April produced plumes that rose to altitudes of 2.1-3.4 km (7,000-11,000 ft) a.s.l. and drifted SW, NE, and SE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 February-12 February 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 6 February produced plumes that rose to altitudes of 1.2-2.1 km (4,000-7,000 ft) a.s.l. and drifted SE. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 January-5 February 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 3 February produced plumes that rose to altitudes of 1.5-2.7 km (5,000-9,000 ft) a.s.l. and drifted SE. Ash was not detected on satellite imagery. On 5 February, a pilot reported an ash plume at an altitude of 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 January-8 January 2008 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported explosions from Sakura-jima on 2 and 7 January. Details of possible resultant ash plumes were unknown.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 December-25 December 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruption plumes from Sakura-jima rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted S during 23-24 December.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 October-30 October 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruption plumes from Sakura-jima rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted E on 29 October.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 August-7 August 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 4 August. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 June-26 June 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruption plumes from Sakura-jima rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted N during 20-21 June. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 June-19 June 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 16 June. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 June-12 June 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that ash plumes from Sakura-jima rose straight up to an altitude of 2.1 km (7,000 ft) a.s.l. on 8, 10, and 11 June. The 10 June plume drifted S. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 May-5 June 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that ash plumes from Sakura-jima rose straight up to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. during 31 May-1 June. During 4-5 June, plumes again rose to the same altitudes as during 31 May-1 June and drifted W, NW, and E. Ash was not detected on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 May-29 May 2007 Citation IconCite this Report

Based on information from JMA and a pilot report, the Tokyo VAAC reported that ash plumes from Sakura-jima rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. during 23-24 and 26-28 May. Plumes drifted E and SE and rose straight up.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 May-22 May 2007 Citation IconCite this Report

Based on information from JMA and a pilot report, the Tokyo VAAC reported that ash plumes from Sakura-jima rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. during 16 and 20-22 May. Plumes drifted NW on 16 May and rose straight up during 20-22 May.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 March-20 March 2007 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an ash plume from Sakura-jima reached an altitude greater than 3.7 km (12,000 ft) a.s.l. on 20 March.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 February-20 February 2007 Citation IconCite this Report

Based on satellite imagery and pilot reports, the Tokyo VAAC reported that an ash plume from Sakura-jima reached an altitude of 1.5 km (5,000 ft) a.s.l. on 15 February.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 February-13 February 2007 Citation IconCite this Report

Based on information from Japan Meteorological Agency (JMA), the Tokyo VAAC reported an explosion from Sakura-jima on 10 February. The altitude and direction of a resultant plume were not reported. On 13 February, an explosion produced a plume that rose to an altitude of 2.1 km (7,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


27 December-2 January 2007 Citation IconCite this Report

Based on information from Japan Meteorological Agency (JMA), the Tokyo VAAC reported an eruption from Sakura-jima on 2 January. The resultant plume reached an altitude of 3.4 km (11,000 ft) a.s.l. and drifted SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 December-19 December 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an explosion from Sakura-jima on 13 December.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 December-12 December 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported an eruption from Sakura-jima on 12 December. The resultant plume reached an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


22 November-28 November 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 22 November produced eruption plumes that reached an altitude of 2.1 km (7,000 ft) a.s.l. and drifted W. On 26 November, plumes reached an unreported altitude.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 November-7 November 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 4 and 5 November eruption plumes from Sakura-jima reached altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. Plumes drifted NE, SE, and E.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


25 October-31 October 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that on 25 and 27 October, ash plumes from Sakura-jima reached altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. Plumes drifted SW and NE, respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 October-24 October 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions from Sakura-jima on 21 October produced plumes that rose straight up to 3.4 km (11,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


4 October-10 October 2006 Citation IconCite this Report

Based on information from JMA and satellite imagery, the Tokyo VAAC reported eruptions at Sakura-jima on 7, 8, and 10 October. Plumes rose to 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted W, S, and SW, respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 September-26 September 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported eruptions at Sakura-jima on 20 and 21 September. A plume from the second eruption rose to 2.4 km (8,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 September-19 September 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption at Sakura-jima on 19 September generated a plume that rose straight up to ~3 km (~10,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 September-12 September 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima produced an eruption cloud on 6 September.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 August-5 September 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruptions at Sakura-jima on 3 and 4 September generated plumes that rose to ~2.7 km (~9,000 ft) a.s.l. and drifted mainly NW and N, respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


23 August-29 August 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that eruptions at Sakura-jima on 22, 23, and 26 August generated plumes that rose to ~2.4 km (~8,000 ft) a.s.l. and drifted mainly SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


9 August-15 August 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption at Sakura-jima on 9 August generated a plume that rose straight up to ~2.4 km (8,000 ft) a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


2 August-8 August 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 2 August generated a plume that rose to ~2.4 km (8,000 ft) a.s.l. and drifted SW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 June-20 June 2006 Citation IconCite this Report

Based on information from JMA and pilot reports, the Tokyo VAAC reported that ash plumes from Sakura-jima reached altitudes of 2.1 km (7,000 ft) a.s.l. during 14, 16, and 19 June.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 June-13 June 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that ash plumes continuing from Sakura-jima reached altitudes of 3.4 km (11,000 ft) a.s.l. during 7-12 June. JMA issued a Volcanic Advisory on 12 June.

On June 10, the Sakura-jima Volcano Research Center reported an increase in low-frequency earthquakes since mid-March and in small tremors with a less than 2 minute duration since mid-May 2006. A thermal anomaly at the volcano grew in size after February 2006.

Sources: Tokyo Volcanic Ash Advisory Center (VAAC); Associated Press; Sakura-jima Volcano Research Center, Disaster Prevention Research Institute (DPRI), Kyoto University; Japan Meteorological Agency (JMA)


31 May-6 June 2006 Citation IconCite this Report

On 4 and 5 June, intermittent eruptions at Sakura-jima, from an upper E-flank vent, near or within the 1946 vent, produced ash clouds that reached unknown heights. No ash was visible on satellite imagery. This was the first reported Sakura-jima eruption from a vent outside the summit crater in 58 years. The 1946 vent was the source of major lava flows that reached the E and S coasts of the former island.

Sources: Reuters; Yukio Hayakawa, Gunma University


26 April-2 May 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 28 April produced an ash plume that rose to 2.1 km (7,000 ft) a.s.l. An explosion on 1 May produced a plume that rose to an unknown height.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 April-25 April 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 19 April generated a plume that rose to ~2.4 km (8,000 ft) a.s.l. and drifted NE.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 February-7 February 2006 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 5 February produced a plume that reached a height of ~1.8 km (6,000 ft) a.s.l. and drifted N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 December-13 December 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 9 December produced a plume to a height of ~2.7 km (9,000 ft) a.s.l. that drifted S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


31 August-6 September 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption occurred at Sakura-jima on 2 September at 0927. The resultant ash plume reached a height of ~2.1 km (7,000) ft a.s.l. and drifted NW.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


20 July-26 July 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions occurred at Sakura-jima on 21 and 22 July. The heights of the resultant plumes were not reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


13 July-19 July 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima produced a plume to ~1.8 km (~5,900 ft) a.s.l. that drifted N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


6 July-12 July 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions occurred at Sakura-jima on 8 and 10 July. The heights of the resultant plumes were not reported.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


1 June-7 June 2005 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 2 June at 0736 produced an ash cloud to an unknown height.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


30 June-6 July 2004 Citation IconCite this Report

On 2 July an explosion at Sakura-jima produced a S-drifting ash cloud to a height of ~1.5 km a.s.l. Another explosion later that day produced an ash cloud to an unknown height.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


16 June-22 June 2004 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an explosion at Sakura-jima on 20 June at 1523 produced an ash cloud to an unknown height.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


19 May-25 May 2004 Citation IconCite this Report

Based on information from JMA, during 19-24 May several explosions at Sakura-jima produced ash clouds. The highest reported ash cloud reached ~2.4 km a.s.l. on 24 May.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


12 May-18 May 2004 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that explosions at Sakura-jima occurred on 15 May at 1107 and on 17 May at 1946, sending ash plumes to heights of ~1.8 km and 2.1 km a.s.l., respectively. A pilot reported ash on 18 May, at a height of ~1.2 km a.s.l., ~23 km S of the Amori region.

Sources: Itar-Tass News; Tokyo Volcanic Ash Advisory Center (VAAC); Associated Press


28 April-4 May 2004 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption at Sakura-jima on 28 April at 1820 produced a plume to a height of ~2.4 km a.s.l. that drifted SE. No ash was visible on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 April-27 April 2004 Citation IconCite this Report

Based on information from JMA, the Tokyo VAAC reported that an eruption of Sakura-jima on 25 April produced an ash plume that rose to a height of ~2.4 km a.s.l. and extended N.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


14 April-20 April 2004 Citation IconCite this Report

Based on information from the Japanese Meterological Agency, the Tokyo VAAC reported that an eruption of Sakura-jima on 17 April produced a gas-and-ash plume that rose to ~3 km a.s.l. and extended W.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


24 March-30 March 2004 Citation IconCite this Report

Based on information from the Japanese Meteorological Agency, the Tokyo VAAC reported that explosions at Sakura-jima on 26 March at 1715 and 27 March at 0607 produced plumes that extended S and rose to ~2.5 km a.s.l. and ~2 km a.s.l., respectively.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


18 February-24 February 2004 Citation IconCite this Report

On 19 and 20 February, explosions at Sakura-jima produced ash clouds that rose to unknown heights. No ash was visible on satellite imagery.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


7 January-13 January 2004 Citation IconCite this Report

According to the Tokyo VAAC, an eruption occurred at Sakura-jima on 12 January around 1430 that produced an ash cloud that rose above 2 km a.s.l.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


3 December-9 December 2003 Citation IconCite this Report

Based on information from the JMA, the Tokyo VAAC reported that on 3 December at 2025 ash was emitted from Sakura-jima, rose to ~2.5 km a.s.l., and extended to the S.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


17 July-23 July 2002 Citation IconCite this Report

Surface observations from Kagoshima airport revealed that on 22 July an ash cloud from Sakura-jima rose to 2.1-2.4 km a.s.l. Ash was visible extending to the SW on satellite imagery. Ash was also observed on 23 July at an unknown altitude.

Source: US Air Force Weather Agency


Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

03/1969 (CSLP 26-69) Eruption from Minami-dake rises 1,500 m and causes ashfall

07/1970 (CSLP 60-70) Lava mass observed in early May; explosion on 12 June

08/1970 (CSLP 60-70) Weak explosion from Minamidake summit crater on 7 July

09/1970 (CSLP 60-70) Multiple explosions in August from Minamidake

10/1970 (CSLP 60-70) Explosions on 6 and 10 September

11/1970 (CSLP 60-70) Large explosion on 14 October; significant activity in late October

12/1970 (CSLP 60-70) Summit crater explosions send ash up to 2,100 m

01/1971 (CSLP 60-70) More December explosions; 19 total during 1970

02/1971 (CSLP 60-70) Incandescent lava lakes clearly visible in both craters

03/1971 (CSLP 60-70) Explosions continue in February

06/1971 (CSLP 60-70) Four moderate explosions in April

09/1972 (CSLP 60-72) Explosions from the summit crater cause ashfall

10/1972 (CSLP 60-72) Large explosion from Minami-dake on 2 October

11/1972 (CSLP 60-72) Frequent explosions in late October and early November, some to 4 km altitude

01/1973 (CSLP 60-72) Frequent explosions in November and December 1972

11/1973 (CSLP 139-73) Minami-dake summit crater quite active throughout 1973

01/1974 (CSLP 139-73) Frequent explosions in late November 1973

07/1974 (CSLP 88-74) Number of explosions increases to 93 in June

08/1974 (CSLP 88-74) Explosions continue; ashfall up to 70 km away

10/1975 (NSEB 01:01) Typical explosive eruptions

05/1976 (NSEB 01:08) Two notable explosions eject tephra, damaging automobiles and crops

06/1976 (NSEB 01:09) Sixteen explosions during 1-5 June

09/1976 (NSEB 01:12) Daily explosions during June-September; frequent ashfall

11/1976 (NSEB 01:14) Frequent small explosions and earthquakes; some heavy ashfall

12/1976 (NSEB 01:15) Continued frequent small explosions and ashfall

02/1977 (NSEB 02:02) Summit explosions continue; lapilli-fall breaks car windows

03/1977 (NSEB 02:03) Explosive activity continues

04/1977 (NSEB 02:04) Only four explosions observed in March

05/1977 (NSEB 02:05) Three explosions in April; one causes minor ashfall

06/1977 (NSEB 02:06) More frequent explosions in May

07/1977 (NSEB 02:07) Explosions send columns up to 2.7 km height

08/1977 (NSEB 02:08) Explosions accompanied by ashfall, scoria ejection, and other activity

09/1977 (NSEB 02:09) Minor ashfalls from explosions; falling scoria starts forest fire

10/1977 (NSEB 02:10) Explosions accompanied by airshocks and scoria ejection

11/1977 (NSEB 02:11) Explosion on 28 November breaks 60 windows in buildings on the S flank

12/1977 (NSEB 02:12) Explosion air shocks break about 100 windows 3 km south of the summit

01/1978 (SEAN 03:01) Strong explosive activity in December and January

02/1978 (SEAN 03:02) Lava mass in crater continues to rise

03/1978 (SEAN 03:03) Fewer explosions in February

05/1978 (SEAN 03:05) Frequent summit crater explosions in March and April

06/1978 (SEAN 03:06) Earthquake swarms and explosions in mid and late May

07/1978 (SEAN 03:07) Frequent explosions continue

08/1978 (SEAN 03:08) Continuing earthquake swarms and explosions

09/1978 (SEAN 03:09) Frequent explosions and continuous ash emission

11/1978 (SEAN 03:11) Explosions persist, but no damage reported

12/1978 (SEAN 03:12) Only one explosion in November; ash ejection between explosions ends

01/1979 (SEAN 04:01) Number of explosions increase; lapilli cracks airplane windows

02/1979 (SEAN 04:02) Explosions continue, but less tephra than last autumn

03/1979 (SEAN 04:03) New dome emplacement in December

04/1979 (SEAN 04:04) Number of explosions drops

05/1979 (SEAN 04:05) Lava dome growing; explosions persist

06/1979 (SEAN 04:06) First explosion-free month in 6 years

07/1979 (SEAN 04:07) Second explosion-free month

08/1979 (SEAN 04:08) No new explosions; activity since 1972 summarized

09/1979 (SEAN 04:09) Explosions resume after 110-day hiatus

10/1979 (SEAN 04:10) Explosions continue

11/1979 (SEAN 04:11) Explosion frequency doubles; aircraft damaged

12/1979 (SEAN 04:12) Frequent explosions continue; tephra cracks another airplane windshield

01/1980 (SEAN 05:01) Explosions continue; activity since 1955 summarized

04/1980 (SEAN 05:04) Explosions and incandescent tephra

05/1980 (SEAN 05:05) Largest number of explosions/month in five years

06/1980 (SEAN 05:06) Activity declines. Explosions/month tabulated since 1955

07/1980 (SEAN 05:07) More frequent explosions

08/1980 (SEAN 05:08) More frequent explosions

09/1980 (SEAN 05:09) Explosions continue

11/1980 (SEAN 05:11) Lapilli and air shocks break windows

12/1980 (SEAN 05:12) Explosions continue; 1980 activity summarized

01/1981 (SEAN 06:01) Earthquake swarm followed by glow and explosions

02/1981 (SEAN 06:02) Fewer explosions

03/1981 (SEAN 06:03) Explosions; two incandescent columns

04/1981 (SEAN 06:04) Fewer explosions

05/1981 (SEAN 06:05) Explosions; ash ejection: B-type earthquakes

06/1981 (SEAN 06:06) Fewer explosions

07/1981 (SEAN 06:07) Explosions decline; seismic and eruptive activity since 1978 summarized

08/1981 (SEAN 06:08) Explosions increase

09/1981 (SEAN 06:09) Frequent explosions, mud-like ejection

10/1981 (SEAN 06:10) Frequent explosions, two incandescent columns

11/1981 (SEAN 06:11) More frequent explosions; tephra breaks windshields

12/1981 (SEAN 06:12) Notable explosions of 1981 tabulated

01/1982 (SEAN 07:01) Frequent explosions continue

03/1982 (SEAN 07:03) Frequent explosions; B-type earthquakes

04/1982 (SEAN 07:04) Explosion rate declines; gas damages crops

05/1982 (SEAN 07:05) Incandescent tephra, ashfall

06/1982 (SEAN 07:06) Frequent explosions; tephra cause minor damage

08/1982 (SEAN 07:08) Explosive activity increases then declines; debris flow

11/1982 (SEAN 07:11) Explosions decline, but plane encounters plume

12/1982 (SEAN 07:12) Frequent explosive activity, ash ejection; little ash

01/1983 (SEAN 08:01) Increased explosive activity, ash ejection

02/1983 (SEAN 08:02) Increased explosive activity; rain-caused debris flows

04/1983 (SEAN 08:04) Explosion rate, seismicity decline; lapilli ejected

05/1983 (SEAN 08:05) Explosions and large plumes; windshields broken

07/1983 (SEAN 08:07) Explosions, tephra emission, and seismicity

12/1983 (SEAN 08:12) Tephra from strong explosions damage cars and buildings

01/1984 (SEAN 09:01) Lapilli damage car windshields; air shock breaks windows; 1983 explosions and ashfalls tabulated

03/1984 (SEAN 09:03) Tephra causes minor damage

05/1984 (SEAN 09:05) Explosive activity continues at high level; debris flows

12/1984 (SEAN 09:12) Summary of 1984 explosions and damage

01/1985 (SEAN 10:01) Explosions with strong air shocks; 1984 activity summary

02/1985 (SEAN 10:02) Explosion lofts lapilli that break 43 windshields

03/1985 (SEAN 10:03) Strong explosions; lapilli cause damage

04/1985 (SEAN 10:04) Vigorous explosions; pyroclastic flow

06/1985 (SEAN 10:06) Explosive activity and eathquakes decline

07/1985 (SEAN 10:07) Frequent explosions; tephra damages nearby towns

10/1985 (SEAN 10:10) Explosive activity declines then increases

11/1985 (SEAN 10:11) Vigorous explosions continue

12/1985 (SEAN 10:12) Eruption plumes on 24th and 31st

01/1986 (SEAN 11:01) Explosions cause damage; data on 30 years of activity

02/1986 (SEAN 11:02) Plumes detected on NOAA satellite images

03/1986 (SEAN 11:03) Less frequent explosions; earthquake swarms

04/1986 (SEAN 11:04) Explosions increase in April

05/1986 (SEAN 11:05) Fewer explosions

06/1986 (SEAN 11:06) Airliner lands safely after flying through ash cloud

07/1986 (SEAN 11:07) Explosions; heavy ashfall

08/1986 (SEAN 11:08) More explosions; earthquake swarms

09/1986 (SEAN 11:09) Explosions and earthquake swarms

11/1986 (SEAN 11:11) Ash and block eruptions; 2.5 m block injures six people

01/1987 (SEAN 12:01) Lapilli damages car windshields

04/1987 (SEAN 12:04) Fewer summit explosions

05/1987 (SEAN 12:05) Minor ash eruptions but no recorded explosions

06/1987 (SEAN 12:06) Explosions and ash emission continue; gas damages trees

07/1987 (SEAN 12:07) Explosions, ash emission continues

08/1987 (SEAN 12:08) Explosions continue

09/1987 (SEAN 12:09) Explosions damage windshields, roofs

10/1987 (SEAN 12:10) Explosions continue; ash plumes; felt airshocks

12/1987 (SEAN 12:12) Large explosions break windows; blocks burn cars

01/1988 (SEAN 13:01) More explosions; windows cracked

02/1988 (SEAN 13:02) More frequent explosions break windows

03/1988 (SEAN 13:03) Strong explosions

04/1988 (SEAN 13:04) Explosions and air shocks; ash accumulation declines

05/1988 (SEAN 13:05) Continued explosions and ash emission

06/1988 (SEAN 13:06) Largest one-day ash accumulation since 1969

07/1988 (SEAN 13:07) Explosions continue

08/1988 (SEAN 13:08) Explosions decrease

10/1988 (SEAN 13:10) Continued explosions, tephra emission, and seismicity

11/1988 (SEAN 13:11) Continued explosions but lighter ashfall

01/1989 (SEAN 14:01) Explosions and ashfall decrease

02/1989 (SEAN 14:02) Monthly ashfall decreases; two explosions

03/1989 (SEAN 14:03) Ash emission; earthquake swarm

04/1989 (SEAN 14:04) Summit explosions diminish

06/1989 (SEAN 14:06) Ash emission but no recorded explosions

08/1989 (SEAN 14:08) First recorded explosion since April

09/1989 (SEAN 14:09) Frequent minor ash emission; two larger explosions

10/1989 (SEAN 14:10) Explosions increase

11/1989 (SEAN 14:11) Explosions eject ash

12/1989 (SEAN 14:12) 1989 activity summarized

02/1990 (BGVN 15:02) Explosions continue; largest ejects ash to 3,000 m

05/1990 (BGVN 15:05) Explosions and ash emissions, structural damage

06/1990 (BGVN 15:06) Continued explosions and ash accumulation

07/1990 (BGVN 15:07) Continued explosions; no damage

08/1990 (BGVN 15:08) Continued vigorous explosions

09/1990 (BGVN 15:09) Several ash emissions but no recorded explosions

10/1990 (BGVN 15:10) Explosions decline, but non-explosive ash emission continues

11/1990 (BGVN 15:11) Windows broken by tephra from strong explosions

12/1990 (BGVN 15:12) Strong explosions; 4,000-m ash cloud

01/1991 (BGVN 16:01) Continued explosions but no damage

02/1991 (BGVN 16:02) Continued explosions but no damage

03/1991 (BGVN 16:03) Most explosions since 1988; no damage

04/1991 (BGVN 16:04) Continued vigorous explosions

05/1991 (BGVN 16:05) Frequent explosions continue

06/1991 (BGVN 16:06) Explosions remain frequent; tephra from one explosion damages houses and cars

07/1991 (BGVN 16:07) Frequent explosions; aircraft windshield damaged

08/1991 (BGVN 16:08) Explosions continue

09/1991 (BGVN 16:09) Continued explosions but decreased ashfall

10/1991 (BGVN 16:10) Fewer explosions

11/1991 (BGVN 16:11) Continued explosions

12/1991 (BGVN 16:12) More frequent explosions and stronger seismicity

01/1992 (BGVN 17:01) Monthly explosion total largest since 1985; increased seismicity

02/1992 (BGVN 17:02) Fewer explosions, but tephra cracks car windshields; seismicity remains high

03/1992 (BGVN 17:03) Fewer explosions but stronger seismicity

04/1992 (BGVN 17:04) Explosions; continued strong seismicity

05/1992 (BGVN 17:05) Explosions and seismic swarms continue

06/1992 (BGVN 17:06) Explosions and seismicity less frequent

07/1992 (BGVN 17:07) Occasional seismically recorded explosions and frequent quiet ash emissions

08/1992 (BGVN 17:08) Seismically recorded explosions halt briefly, but quiet ash emission continues

09/1992 (BGVN 17:09) Explosions and quiet ash emissions

10/1992 (BGVN 17:10) Increased explosive activity feeds ash plumes and incandescent columns

11/1992 (BGVN 17:11) Explosions and ash emission continue

12/1992 (BGVN 17:12) Continued explosions; no damage

01/1993 (BGVN 18:01) Continued explosions; no damage

02/1993 (BGVN 18:02) Explosions continue; three earthquake swarms

03/1993 (BGVN 18:03) 40-hour-long earthquake swarm

04/1993 (BGVN 18:04) Explosive activity continues; windshield damaged

05/1993 (BGVN 18:05) Few quiet ash eruptions; no explosions

06/1993 (BGVN 18:06) Several quiet ash eruptions; no explosions for 99 days

08/1993 (BGVN 18:08) Longest non-eruptive period since 1972

10/1993 (BGVN 18:10) Explosions resume after 201 explosion-free days

11/1993 (BGVN 18:11) Explosive activity continues since late October resumption

12/1993 (BGVN 18:12) Explosive activity increases, but produces no damage

01/1994 (BGVN 19:01) Explosive activity decreases from December levels; no damage

02/1994 (BGVN 19:02) Explosions continue; one windshield cracked

04/1994 (BGVN 19:04) No earthquake swarms and only one explosion

05/1994 (BGVN 19:05) Explosive eruptions resume

06/1994 (BGVN 19:06) Frequent explosions; ashfall

07/1994 (BGVN 19:07) Volcanism continues; 14 explosive eruptions

08/1994 (BGVN 19:08) Number of eruptions and amount of ashfall increase

09/1994 (BGVN 19:09) Eruptive activity decreases

10/1994 (BGVN 19:10) Explosive eruptive activity continues but causes no damage

11/1994 (BGVN 19:11) Explosive activity continues; summary of aviation hazards and mitigation efforts

12/1994 (BGVN 19:12) Explosive ash eruptions continue

01/1995 (BGVN 20:01) Explosive eruptions cause ashfall but no damage

03/1995 (BGVN 20:03) Explosive eruptions send plumes 3-4 km above the summit

05/1995 (BGVN 20:05) Explosive ash eruptions continue

07/1995 (BGVN 20:07) Only one explosive eruption during July

08/1995 (BGVN 20:08) Explosive activity 23-25 August, dense ash cloud closes a highway

09/1995 (BGVN 20:09) Explosions continue, but at much lower levels compared to August

10/1995 (BGVN 20:10) Explosive activity continues

12/1995 (BGVN 20:11) Explosive eruptions continue to generate ash plumes

01/1996 (BGVN 21:01) Explosive eruptions and ashfalls continue

02/1996 (BGVN 21:02) Explosive ash eruptions continue

03/1996 (BGVN 21:03) Frequent explosive ash eruptions continue

05/1996 (BGVN 21:05) Explosive activity continues, decreased activity in May

06/1996 (BGVN 21:06) Explosive activity continues, but at decreased levels in June

07/1996 (BGVN 21:07) Minor activity continues

10/1996 (BGVN 21:10) Seven explosive eruptions in September and October from Minami-dake

01/1997 (BGVN 22:01) Four explosive eruptions from Minami-dake in December and January

09/1997 (BGVN 22:09) Relatively quiet but an 11 May explosion sent bombs hundreds of meters down the flanks

01/1998 (BGVN 23:01) Increased number of explosions during December-January

02/1998 (BGVN 23:02) Several explosions during January-February

04/1998 (BGVN 23:04) Amid ongoing explosions, a 19 May seismic swarm yields 220 earthquakes in 4 hours

05/1999 (BGVN 24:05) 1998-99 summary report; recent tephra deposits comprise about 3 x 105 tons/month

08/1999 (BGVN 24:08) Larger than normal eruptions in late July and early August

02/2000 (BGVN 25:02) Frequent explosive eruptions continue from Minami-dake

10/2000 (BGVN 25:10) Explosion, lapilli and ash fall; pilot encounters ash cloud on 7 October

04/2003 (BGVN 28:04) Ash plume observed in July 2002; plume photo from 17 April 2003

05/2004 (BGVN 29:05) Frequent eruptions and ash plumes; 15 May plume noted by news media

06/2006 (BGVN 31:06) First eruption outside of the summit crater in 58 years

04/2007 (BGVN 32:04) Eruption from E-slope Showa crater on 4 June 2007

03/2009 (BGVN 34:03) Recent (2007-2009) explosive eruptions and intermittent plumes

08/2009 (BGVN 34:08) May-October 2009, ongoing explosive eruptions

10/2011 (BGVN 36:10) During 2011, pyroclastic flows, frequent ash plumes, and lava emission

05/2012 (BGVN 37:05) Explosions during November 2011-July 2012; ash and health

01/2014 (BGVN 39:01) Frequent explosions during 2012-13; ashfall on Kagoshima City

11/2015 (BGVN 40:11) Explosions continue in 2014, averaging more than one eruption per day

02/2018 (BGVN 43:02) Explosions gradually decrease in frequency during 2015-2016

07/2018 (BGVN 43:07) Activity resumed in March 2017 and remained relatively low through the year

08/2018 (BGVN 43:08) Activity increased at Minamidake and decreased at Showa crater in early 2018

01/2019 (BGVN 44:01) Ash plumes continue at the Minamidake crater from July through December 2018

07/2019 (BGVN 44:07) Explosions with ejecta and ash plumes continue weekly during January-June 2019

01/2020 (BGVN 45:01) Ongoing explosions with ejecta and ash plumes, along with summit incandescence, during July-December 2019

07/2020 (BGVN 45:07) Near-daily explosions with ash plumes continue, large block ejected 3 km from Minamidake crater on 4 June 2020

01/2021 (BGVN 46:01) Intermittent explosions continue during July through December 2020

08/2021 (BGVN 46:08) Intermittent explosions, ash plumes, ashfall, and incandescent ejecta through June 2021

01/2022 (BGVN 47:01) Minor ash emissions July-December 2021

07/2022 (BGVN 47:07) Explosive events, plumes, minor ashfall, and crater incandescence during January-June 2022

01/2023 (BGVN 48:01) Explosions, ash plumes, and ashfall during July-December 2022




Information is preliminary and subject to change. All times are local (unless otherwise noted)


March 1969 (CSLP 26-69)

Eruption from Minami-dake rises 1,500 m and causes ashfall

Card 0473 (24 March 1969) Eruption from Minami-dake rises 1,500 m and causes ashfall

The following information is from the "Asahi," Tokyo, 9 March 1969. At 0742, 8 March, Minami-dake emitted smoke up to a height of 1,500 m. A large quantity of volcanic ash fell on tangerine orchards at the foot of the volcano and on Kagosima Airport on the opposite shore.

Information Contacts: Tokiko Tiba, Department of Geology, The National Science Museum, Tokyo, Japan.


July 1970 (CSLP 60-70)

Lava mass observed in early May; explosion on 12 June

Card 0973 (15 July 1970) Lava mass observed in early May; explosion on 12 June

"A lava mass (about 100 m across) had appeared in the summit crater (Minamidake) . . . at the beginning of May, but activities of volcanic smoke emission and volcanic earthquakes did not exist. At 2031 JST on 12 June 1970, the crater exploded for the first time since the lava mass had been observed. This explosion was the third in this year. A small airshock was felt but the other phenomenon could not be observed owing to night time.

Information Contacts: Yosihiro Sawada, Seismological Section, Japan Meteorological Agency (JMA), Tokyo, Japan.


August 1970 (CSLP 60-70)

Weak explosion from Minamidake summit crater on 7 July

Card 0992 (18 August 1970) Weak explosion from Minamidake summit crater on 7 July

"Sakurazima volcanic explosion 7 July 1970, southern Kyushu, Japan. Minamidake, the summit crater of this volcano exploded at 0653 JST on 7 July 1970. Weak explosion-sound and airshock were observed. This explosion of the volcano is the fourth one this year."

Information Contacts: Y. Sawada, JMA.


September 1970 (CSLP 60-70)

Multiple explosions in August from Minamidake

Card 1009 (14 September 1970) Multiple explosions in August from Minamidake

"Sakurazima volcanic explosion 13, 19, and 30 August 1970, southern Kyushu, Japan. Minamidake, the summit crater, exploded at 0610 and 0939 JST on the 13th, 1214 JST on the 19th, and 1645 JST on the 30th of August. The state of the explosions at the crater could not be observed owing to clouds. This volcano had exploded eight times by August of this year."

Information Contacts: Y. Sawada, JMA.


October 1970 (CSLP 60-70)

Explosions on 6 and 10 September

Card 1031 (14 October 1970) Explosions on 6 and 10 September

Minamidake, the summit crater, exploded at 0151 JST on the 6th, 1138 JST on the 10th, and 0952 JST on the 19th of September. Explosions on the 6th and the 10th emitted great quantities of cinders on the middle flank of this volcano.

Information Contacts: Y. Sawada, JMA.


November 1970 (CSLP 60-70)

Large explosion on 14 October; significant activity in late October

Card 1057 (27 November 1970) Large explosion on 14 October; significant activity in late October

The new crater (W-crater) which had opened at Minamidake in August last year exploded at 1143 JST on 14 October 1970. Large quantities of volcanic smoke with a great explosive sound and roaring sounds were given out from the crater. Volcanic flame about 20 m across and 20-30 m high was observed at this crater during the night of 23 October and continued until 29 October. Smoke from the crater was given out until 30 October. Main summit craters (we call them A and B craters) at Minamidake have emitted out large quantities of volcanic smoke.

Information Contacts: Y. Sawada, JMA.


December 1970 (CSLP 60-70)

Summit crater explosions send ash up to 2,100 m

Card 1074 (22 December 1970) Summit crater explosions send ash up to 2,100 m

The summit crater of Minamidake (South peak) exploded at 0159 JST on the 12th, 2255 JST on the 15th, and 1147 JST on the 16th of November. The explosion on the 15th emitted volcanic smoke 1,000 m high, with the precipitation of cindering ash, an explosive sound and air shock. The explosion on the 16th emitted volcanic smoke 2,100 m high, with an explosive sound and air shock.

Information Contacts: Y. Sawada, JMA.


January 1971 (CSLP 60-70)

More December explosions; 19 total during 1970

Card 1095 (20 January 1971) More December explosions; 19 total during 1970

Summit crater, Minamidake, exploded at 0732 and 2352 JST on 16 December, 0428 on 20 December, 1401 JST on 21 December 1970. On the occasion of the explosion on 21 December, a large amount of volcanic smoke went up about 1,600 m high. In 1970, Sakurazima exploded 19 times in total.

Information Contacts: Y. Sawada, JMA.


February 1971 (CSLP 60-70)

Incandescent lava lakes clearly visible in both craters

Card 1135 (23 February 1971) Incandescent lava lakes clearly visible in both craters

Minamidake summit crater exploded at 1023 JST on 1 January and at 1457 JST on 11 January 1971. On the occasion of the latter explosion, a large quantity of volcanic smoke was given out which reached a height of about 3,000 m.

Information Contacts: Y. Sawada, JMA.


March 1971 (CSLP 60-70)

Explosions continue in February

Card 1156 (22 March 1971) Explosions continue in February

Three volcanic explosions at Minamidake summit crater occurred at 2128 JST on 14 February, at 1346 JST on 16 February, and at 0334 JST on 20 February, 1971. On the occasion of the explosion on 16 February, a large quantity of volcanic smoke (with a small amount of ash-fall went up to a height of about 1,800 m. Two other explosions took place at night and the details are unknown.

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


June 1971 (CSLP 60-70)

Four moderate explosions in April

Card 1226 (01 June 1971) Four moderate explosions in April

"Minamidake (south peak), summit crater of this volcano exploded at 2214 on 7 April, 0553 on 8 April, 2348 on 10 April, and 0333 on 29 April 1971. The details of these activities were unknown owing to night-time, but according to maximum amplitudes (25, 35, 28, and 18µ, respectively) of explosion earthquakes obtained by the seismograph installed at a point 5.4 km WNW of Minamidake, the intensities of these explosions were minor-to-moderate ones. On the occasion of the explosion on 8 April, a weak explosion sound and moderate air shock were felt. And, when the explosion on 10 April took place, 2,000-m-high volcanic smoke, a small amount of cinder-fall on the upper flank, weak air shock and weak explosion sound were observed."

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


September 1972 (CSLP 60-72)

Explosions from the summit crater cause ashfall

Card 1448 (26 September 1972) Explosions from the summit crater cause ashfall

[Explosions from Minamidake continued during 17 August-15 September 1972 (table 1).]

Table 1. Explosive activity from the Minami-dake crater at Sakura-jima, 17 August-15 September 1972. Courtesy of JMA.

Date Time (JST) Plume Height (m) Description
17 Aug 1972 0950 1000 Much smoke and ashfall.
13 Sep 1972 1820 3000 Much smoke and ashfall. Volcanic thunder in rising smoke. Vegetable fields were damaged rather heavily by the ashfall.
14 Sep 1972 2244 -- Unknown (night-time).
15 Sep 1972 1108 3100 Much smoke. Cinders fell on the middle flank. Medium ashfall. One air shock was felt.
15 Sep 1972 1745 4000 Much smoke and ashfall.

Active emissions of volcanic smoke with ashfalls continued during 14 September. Explosions which occurred on 13 and 15 of September were some of the most remarkable ones in recent years. Many micro-volcanic earthquakes were registered, especially from 0600 on 14 September on three seismographs installed around this volcano; (e.g. 320 shocks from 0900 to 1400 and 60 shocks from 2100 to 2300 on 14 September). From interpretation of previous activities, elevation of the lava mass in the summit crater is experimentally expected.

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


October 1972 (CSLP 60-72)

Large explosion from Minami-dake on 2 October

Card 1463 (06 October 1972) Large explosion from Minami-dake on 2 October

"On 2 October [at] 1329 GMT, Minamidake crater "A" blew up with a terrific explosion (18th explosion this year). Rolls of volcanic thunder were heard twenty-three times. Volcanic ejecta (ash and pumice) fell within an area above 300 me altitude, but no lava flow took place. Air vibration of 3.5 millibars from the explosion was recorded on the biograph of the meteorological observatory of Kagoshima district. The maximum amplitude of vibration by explosion earthquake was 72 microns. The 1,070-m S peak of Sakurazima Island in Kagoshima Bay erupted twice early [on] 6 October, but there were no casualties. The eruptions registered a maximum amplitude of ten and fifteen microns at 0439 JST, and 0810am JST, respectively. The second eruption caused spewing up of rocks from the crater near the top of the peak. The eruptions were the 19th and 20th recorded this year. Earlier, the previous eruption that occurred on 2 October was the biggest since November 1957.

Information Contacts: Tokiko Tiba, Department of Geology, The National Science Museum, Tokyo, Japan.


November 1972 (CSLP 60-72)

Frequent explosions in late October and early November, some to 4 km altitude

Card 1487 (15 November 1972) Details of September-October explosions

Minamidake summit crater exploded in September [once on the 13th, 14th, 21st, 25th, and 30th, and three times on the 15th]. Of these explosions, the explosion on the 13 September was a rather remarkable one. Volcanic smoke rose about 3,000 m high with heavy ashfalls. A wide area of vegetable fields was heavily damaged by the ashfall. Emission of a large quantity of smoke continued for about three hours and volcanic lightning was seen in the rising smoke. Some of the other explosions were also rather strong, and they were accompanied by cinders and ashfalls and much volcanic smoke (max. 4,000 m high). The appearance and rising of a lava mass in the summit crater is expected based on these activities and seismological observations by the Kagosima local Meteorological Observatory.

Minamidake exploded in October [on the 2nd (1), 6th (2), 27th (1), 28th (8), 29th (3), and 30th (1)]. During these explosions, emission of much smoke (sometimes 3,000-4,000 m high) was frequently observed. After the explosions in the early part of the month, felt earthquakes (intensity II on the JMA scale) took place, and before the explosions in the latter part of the month there were swarms of shallow micro-earthquakes. The explosions were accompanied by much volcanic smoke (max. about 4,000 m), explosion-earthquakes and cinder and ashfalls. Volcanic lightning and pillars of fire were also observed. The greatest explosion was the one on 2 October, one of the most remarkable ones over the past two or three years. It was greater than the explosion on 13 September. Many cinders fell onto the lower flank (max. 3 km from the crater) of this volcano, and these cinders caused forest fires on several parts of the middle flank. Pillars of fire caused by red-hot cinders were sometimes seen and volcanic lightning was frequently observed in the rising smoke. The air-shock from this explosion was felt even at Hitoyosi, 74 km NE of the volcano. Damage was less than that which occurred on 13 September.

Card 1488 (20 November 1972) Thirteen explosions during 1-5 November

Minamidake summit crater continued exploding in November [on the 1st (2), 2nd (3), 3rd (5), 4th (2), and 5th (1)]. During these explosions, a great deal of volcanic smoke with cinder and ashfalls rose to a maximum height of 4,000 m. Volcanic lightning and pillars of fire were sometimes observed in rising volcanic smoke. The greatest explosion of this series was the one at 1236 JMT on the first of the month. A great quantity of volcanic smoke with heavy ashfalls rose to 4,000 m, and many cinders fell down onto the middle flank, causing forest fires. During these activities, active emissions of volcanic smoke with ashfalls continued. After the explosion on 5 November, however, emission of volcanic smoke stopped. Many micro-earthquakes (shallow ones) registered on seismographs of the Kagosima Local Meteorological Observatory through 7 November.

Information Contacts:
Card 1487 (15 November 1972) Seismological Section, Japan Meteorological Agency, Tokyo, Japan.
Card 1488 (20 November 1972) Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


January 1973 (CSLP 60-72)

Frequent explosions in November and December 1972

Card 1536 (17 January 1973) Frequent explosions in November and December 1972

On 16 November, active explosions at Minamidake summit crater resumed. From 16 November through 30 November, explosions took place 32 times. The total number of explosions in November was 45. Some of these were strong ones, with a great quantity of volcanic smoke (max. height: more than 3,000 m), red-hot cinder-falls onto the middle flank, pillars of fire (sometimes 200-300 m high), and resulting forest fires due to red-hot cinders. The amplitudes of some explosion-earthquakes registered with the JMA-59 type seismograph (magnification:100) at the Kagosima Local Meteorlogical Observatory (about 12 km W of the active crater) reached 40 microns in the explosions on 16 and 28 November. These amplitudes were large compared with the usual explosions. Around 18 November the so-called B-type volcanic earthquakes swarmed, and then, from 21 November, the frequency of explosions increased. [Explosions in the second half of November occurred on the 16th (1), 17th (1), 18th (2), 19th (1), 20th (1), 21st (3), 22nd (1), 23rd (3), 24th (7), 25th (3), 26th (1), 27th (1), 28th (6), and 30th (1).]

In addition to these explosions, remarkable emissions of volcanic smoke were sometimes observed. Explosions at Minamidake summit crater continued until the middle of December. Some of them were rather strong explosions, i.e. with great quantities of volcanic smoke (more than 3,000 m high), red-hot cinder-falls onto the middle flank, and resultant forest fires caused by red-hot cinders. The number of explosions in December was 28, and the total number in 1972 was 108. Large amplitudes of explosion-earthquakes (the maximum was 105 microns) were sometimes registered with the JMA-59 type seismograph at Kagosima Local Meteorlogical Observatory, and amplitudes of 30-60 microns were sometimes observed. These amplitudes show that the explosions were strong ones. [Explosions in December occurred on the 1st (5), 2nd (4), 3rd (1), 8th (1), 9th (3), 10th (3), 11th (3), 12th (4), and 13th (4).]

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


November 1973 (CSLP 139-73)

Minami-dake summit crater quite active throughout 1973

Card 1738 (01 November 1973) Minami-dake summit crater quite active throughout 1973

The Minamidake summit crater . . . has been quite active throughout most of 1973. In June, four explosions occurred on the first of the month, with smoke reaching an altitude of 5,000 m, and large quantities of cinders, ash, and lapilli being ejected. In July, explosions took place on the 17th and the 22nd. In August, there were a total of 17 explosions. On 18 and 19 August, the smoke reached an elevation of 4,000 m, and on 24 August 3,000 m. Activity increased significantly in September and October, with 14 explosions recorded in September (max. height of smoke was 3,000 m), and 36 explosions during the first 18 days of October. The explosion on 18 October was the 76th this year. The maximum height of the volcanic smoke was 3,500 m and 40 micron explosion-earthquakes were frequently recorded at the Kagosima Local Meteorlogical Observatory.

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


January 1974 (CSLP 139-73)

Frequent explosions in late November 1973

Card 1781 (23 January 1974) Frequent explosions in late November 1973

Emissions of volcanic smoke from Minamidake summit crater became active again on 27 November, and frequent explosions with detonations, air-shocks, and strong emissions of smoke (max. 4,000 m high) occurred (table 2). The explosions on 28 November ejected a great amount of lapilli to the southeast of the crater, and windshields of 15 cars driving on a road were broken by this ejecta. The total number of explosions in December was 31, and the total for the 1973 was 144.

Table 2. Number of explosions from the Minami-dake summit crater at Sakura-jima, 27 November-25 December 1974. Courtesy of JMA.

Date Explosions
27 Nov 1974 2
28 Nov 1974 9
29 Nov 1974 13
30 Nov 1974 10
01 Dec 1974 5
02 Dec 1974 4
03 Dec 1974 2
05 Dec 1974 4
06 Dec 1974 1
07 Dec 1974 2
10 Dec 1974 1
14 Dec 1974 1
15 Dec 1974 2
16 Dec 1974 1
17 Dec 1974 1
18 Dec 1974 1
20 Dec 1974 1
21 Dec 1974 1
22 Dec 1974 1
23 Dec 1974 1
25 Dec 1974 1

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


July 1974 (CSLP 88-74)

Number of explosions increases to 93 in June

Card 1886 (17 July 1974) Number of explosions increases to 93 in June

Recently, the Sakurazima volcano became quite active, and the occurrences of explosions increased. There were 93 explosions in June, and a total of 198 during the first six months of this year. Some of the explosions were accompanied by small to medium amounts of fragments ejected onto the flanks of the volcano, plus ashfalls and flame. The smoke generally reached heights of 2,000 m; the highest altitude reached was 3,300 m. According to the Kagosima Local Meteorlogical Observatory, the total amount of ash that fell in May was 133.5 grams/m2 at Kagosima city, about 10 km from the Minamidake summit crater of Sakurazima.

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


August 1974 (CSLP 88-74)

Explosions continue; ashfall up to 70 km away

Card 1908 (21 August 1974) Explosions continue; ashfall up to 70 km away

The activity of the Minamidake summit crater . . . is continuing. The total number of volcanic earthquakes recorded on the seismograph on the upper reaches of Mt. Sakurazima, and explosions at the Minamidake summit crater in July, were 26,069 and 49, respectively. Some of the explosions were accompanied by small to medium amounts of ejected fragments plus ash and flame. The smoke generally rose to heights of from 1,000-2,000 m with the highest being 3,000 m. About 2 cm of ashes fell at Sakurazima city, 5 km from Minamidake summit crater, and some ash reached Minamata city, about 70 km from Minamidake. Crops, such as mandarin oranges, vegetables, and mulberry trees were damaged considerably by the ashes.

Information Contacts: Seismological Section, Japan Meteorological Agency, Tokyo, Japan.


October 1975 (NSEB 01:01) Citation IconCite this Report

Typical explosive eruptions

During the summer of 1975 Sakura-jima was normally active. There were 16 explosions in September (figure 1). The highest eruption cloud reached a few thousand meters altitude.

Figure (see Caption) Figure 1. Summary table of explosions from Minami-dake crater at Sakura-jima, October 1975-December 1976. Data courtesy of JMA. [October 1975-May 1976 data were added, and errors in the June 1976-December 1976 data have been corrected from the originally published material.]

Information Contacts: JMA, Tokyo.


May 1976 (NSEB 01:08) Citation IconCite this Report

Two notable explosions eject tephra, damaging automobiles and crops

Two notable explosions occurred during May. Volcanic activity had been increasing during 1976 and dark smoke had been frequently observed since an explosion on 7 April. On 13 May at 0738, an explosion sent a cloud to 2,000 m height. This moderate explosion was the 29th of 1976 at the Minami-dake summit crater.

Large amounts of pumice and lapilli fell onto the E slope of the crater. At Sakura-jima-guchi, 5.5 km ESE of the crater, up to 3 cm of pumice was deposited (as measured on a road), and maximum ejecta size was 25 x 25 x 4 cm. Automobiles and crops in the area were damaged by the ashfall.

On 17 May at 1342, an eruption cloud reached 2700 m height (not 16 miles as reported by UPI in the press) following the 31st and largest explosion recorded in 1976. Tiba reported blocks up to l m across falling 2.5 km from the vent. Shimozuru reported cinders 2-6 cm in size at Arimura, 3 km SSE of the crater. At Furusato, 3 km S of the crater, and at a school 7 km SE of the crater, window glass was broken by the strong airshock which measured 0.34 millibars on a microbarograph 10 km W of the crater. Volcanic tremor occurred 32-36 hours before this major eruption, then volcanic earthquakes continued up to 22 hours before its onset.

Both explosions took place at the newly-opened (since 10 December 1975) 40-m-diameter crater SE of crater A at Minami-dake. An estimated 170,000 tons of molten lava filled the bottom of crater A from 90 to 50 m depth.

Information Contacts: JMA, Tokyo; D. Shimozuru, ERI, Tokyo; T. Tiba, National Science Museum, Tokyo.


June 1976 (NSEB 01:09) Citation IconCite this Report

Sixteen explosions during 1-5 June

Sixteen explosions were recorded between 1-5 June, but none 6-20 June.

Information Contacts: JMA, Tokyo.


September 1976 (NSEB 01:12) Citation IconCite this Report

Daily explosions during June-September; frequent ashfall

An explosion at 0727 on 5 June deposited a small amount of lapilli (to 1 cm in diameter) at Kurokami, 5 km E of the crater. Maximum June ash cloud height exceeded 3000 m. Ashfalls were frequent during late June at Kagoshima City, 10 km W of the crater. Volcanic earthquakes occurred frequently. July explosions were small, but ash emission was heavy. The maximum height of ash clouds was 3000 m. Kagoshima City continued to experience frequent ash falls. The July 26th explosion occurred at 0357, producing a felt air shock. Vibrations continued to be felt after the explosion at Higashi-Sakura-jima, 3 km SSW of the crater.

Detonations, air shocks, cinder falls, [an incandescent column], and frequent ashfalls were noted during August. The maximum eruption cloud height 1-10 September was 2000 m.

Information Contacts: JMA, Tokyo.


November 1976 (NSEB 01:14) Citation IconCite this Report

Frequent small explosions and earthquakes; some heavy ashfall

Most of the explosions 10 September-28 October were small. [Ash cloud] emission was also observed, reaching a maximum of 3000 m [above the crater]. Volcanic earthquakes were frequent. The explosion at 1142 on 10 September deposited a large quantity of ash and lapilli at Kagoshima City. The 23 September explosion at 2015 was accompanied by a large detonation, an air shock, [an incandescent column], thunder, and rumbling. A large amount of ash and lapilli were deposited on the S flank, 3 km from the crater. Activity on 2 October began at 1238 and lasted about 3 hours, causing a heavy ashfall W of the vent. A large detonation and air shock were observed at 0028 on 6 October. This explosion caused a cinder fall on the middle flank.

Information Contacts: JMA, Tokyo.


December 1976 (NSEB 01:15) Citation IconCite this Report

Continued frequent small explosions and ashfall

Almost all 1 November-20 December explosions were small. Strong detonations, air shocks and [incandescent columns] were sometimes observed at the Kagoshima meteorological observatory. Emission of [ash] clouds, some of which rose 3000 m above the crater, was almost continuous, and ashfalls around the crater were frequent. At the time of one of these (21 October at 1228), a large quantity of ash moved down the W slope, but it was not possible to confirm it as a nuée ardente. On 4 November at 1700, an overflight revealed a red-hot lava mass [or mound] (40 m across) at the bottom of the summit crater. A weak [reflection of] glow, probably caused by the lava, was sometimes seen during October.

Information Contacts: JMA, Tokyo.


February 1977 (NSEB 02:02) Citation IconCite this Report

Summit explosions continue; lapilli-fall breaks car windows

6 December, 2149: A moderately strong detonation, air shock, [incandescent column] and volcanic [lightning] were reported. Incandescent tephra fell on the middle flank.

11 December, 0345: Considerable fall of tephra, including [scoria] (4 cm maximum diameter) and non-scoriaceous lapilli (2 cm maximum diameter) E of the summit. Two cm of ash fell 3 km SE of the summit.

13 December, 0106: Lapilli (4.5 cm maximum diameter) broke car windows 3.5 km E of the summit.

[On 6 December] a swarm of about 500 volcanic earthquakes occurred during a 3-hour period. . . .

Information Contacts: JMA, Tokyo.


March 1977 (NSEB 02:03) Citation IconCite this Report

Explosive activity continues

The explosion at 1632 on 31 January (figure 2) deposited a considerable quantity of lapilli [S of the crater]. At 1005 the next day, a strong air shock broke [65 windowpanes at a school in Tarumizu City, about 10 km SE of the crater]. After the l February explosions, [ash] emission from the crater ceased until 6 March [but white vapor emission continued from 2 February until the 6 March explosions]. The number of volcanic earthquakes decreased in February and March.

Figure (see Caption) Figure 2. Summary table of explosions from Minami-dake crater at Sakura-jima, 1977. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


April 1977 (NSEB 02:04) Citation IconCite this Report

Only four explosions observed in March

A slight air shock from the 15 March explosion was felt at the Kagoshima Meteorological Observatory.

Information Contacts: JMA, Tokyo.


May 1977 (NSEB 02:05) Citation IconCite this Report

Three explosions in April; one causes minor ashfall

The 30 April eruption cloud rose 2,700 m above the crater and caused a minor ashfall on the SE flank.

Information Contacts: JMA, Tokyo.


June 1977 (NSEB 02:06) Citation IconCite this Report

More frequent explosions in May

Sixteen explosions were recorded 1-16 May. Local earthquakes continued.

Information Contacts: JMA, Tokyo; D. Shackelford, CA.


July 1977 (NSEB 02:07) Citation IconCite this Report

Explosions send columns up to 2.7 km height

June explosions were accompanied by air shocks, rumbling of about 10 seconds duration, and explosion sounds. Eruption columns rose to 2,700 m from the crater and contained some cinders.

Information Contacts: JMA, Tokyo.


August 1977 (NSEB 02:08) Citation IconCite this Report

Explosions accompanied by ashfall, scoria ejection, and other activity

Ashfalls, scoria ejection, incandescence, airshocks, and rumbling frequently accompanied the July explosions. Eruption clouds rose more than 2,800 m on 3 July, more than 3,000 m on 6 July, and about 2700 m on 20 July. . . .

Information Contacts: JMA, Tokyo; D. Shackelford, CA.


September 1977 (NSEB 02:09) Citation IconCite this Report

Minor ashfalls from explosions; falling scoria starts forest fire

Ash clouds rose to a maximum of 2,800 m above the crater in August, but ashfalls were minor. Falling scoria from an explosion at 1317 on 29 August caused [grass fires at 8 points] on the SW flank. [The fires were extinguished in a few minutes.]

Information Contacts: JMA, Tokyo.


October 1977 (NSEB 02:10) Citation IconCite this Report

Explosions accompanied by airshocks and scoria ejection

Ash clouds rose to a maximum of 2,100 m above the crater during September. Explosions were accompanied by air shocks and scoria ejection.

Information Contacts: JMA, Tokyo.


November 1977 (NSEB 02:11) Citation IconCite this Report

Explosion on 28 November breaks 60 windows in buildings on the S flank

Maximum ash cloud height during October was 2,500 m above the crater. Some incandescent material was ejected and reflected glow was occasionally observed. The air shock from an explosion at 0347 on 30 November broke [102 windowpanes] in villages about 3 km S of the summit. Tephra started grass fires, but these were quickly extinguished. No [injuries] resulted from the explosion, the 21st to occur in November.

Information Contacts: JMA, Tokyo; Japanese Press.


December 1977 (NSEB 02:12) Citation IconCite this Report

Explosion air shocks break about 100 windows 3 km south of the summit

. . . Maximum November ash cloud height was 2,200 m above the crater, on the 2nd. Volcanic thunder was heard on more than 20 occasions during the month.

Information Contacts: JMA, Tokyo.


January 1978 (SEAN 03:01) Citation IconCite this Report

Strong explosive activity in December and January

Tephra from explosions at 1220 on 8 December, 1834 on 20 December, 0621 and 1507 on 22 December, and on 27 January, caused [grass] fires. A 300-m column of incandescent ejecta was observed at 0534 on l December, and reflected glow was seen between 0322 and 0325 on 10 December. The air shock from an explosion at 2140 on 8 December broke three [windowpanes] in a nearby village. Ash clouds rose 2,000 m above the crater on 6, 8, and 22 December.

Information Contacts: JMA, Tokyo.


February 1978 (SEAN 03:02) Citation IconCite this Report

Lava mass in crater continues to rise

Tephra from an explosion on 25 December cracked the windshield of an All Nippon Airways aircraft passing over the Hayato area, about 20 km NE of the crater.

Maximum January ash cloud height was 1,900 m above the crater on the 23rd. Incandescence, scoria ejection, air shocks, and rumbling accompanied the activity. Aerial observations in mid-January confirmed the continued growth of the lava mass present in the crater since September. Several earthquake swarms . . . were recorded during December and January.

Information Contacts: JMA, Tokyo; D. Shackelford, CA.


March 1978 (SEAN 03:03) Citation IconCite this Report

Fewer explosions in February

February explosions were accompanied by air shocks and rumbling. Scoria from explosions at 0024 on 8 February and 0218 on 26 February caused [grass] fires. The maximum February cloud height was 1700 m above the crater, at 0850 on the 25th.

Information Contacts: JMA, Tokyo.


May 1978 (SEAN 03:05) Citation IconCite this Report

Frequent summit crater explosions in March and April

Powerful explosions from the summit crater of Minami-dake have become more frequent since summer 1977 (figures 2 and 3). Beginning in August, explosions have been preceded by earthquake swarms lasting several days. . . . This pattern has often occurred 4-5 times/month and has enabled scientists at the JMA's Sakura-jima Observatory to [forecast] the explosions. The frequent property damage that has occurred near the volcano since last summer continued in March and April. Many windowpanes and a car windshield were broken by airshocks and tephra during March. Incandescence was also observed during March and April.

Figure (see Caption) Figure 3. Summary table of explosions from Minami-dake crater at Sakura-jima, 1978. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


June 1978 (SEAN 03:06) Citation IconCite this Report

Earthquake swarms and explosions in mid and late May

The air shock from the 22 May explosion broke five windowpanes. Earthquake swarms . . . occurred in mid and late May, correlated with an increase in the number of explosions during the same period. A swarm of exceptionally long duration (16 hours) on 30 May was followed by four explosions on the 31st.

Information Contacts: JMA, Tokyo.


July 1978 (SEAN 03:07) Citation IconCite this Report

Frequent explosions continue

About 20 earthquakes . . . were recorded in June. . . . Consequently, JMA scientists believe that a large volume of magma remained on or just under the crater bottom in early June. Reuters reported a loud explosion on 21 July, producing a 1600-m eruption column, and two explosions on 23 July, throwing incandescent ejecta 2,500 m above the vent. UPI reported that strong winds from a typhoon spread about 2.5 cm of ash within 5 km of the summit after an explosion on 31 July.

Information Contacts: JMA, Tokyo; Reuters; UPI; D. Shackelford, CA.


August 1978 (SEAN 03:08) Citation IconCite this Report

Continuing earthquake swarms and explosions

During July, 25 explosions from the summit crater of Minami-dake were recorded. Large quantities of tephra (blocks, lapilli, and ash) were ejected by three explosions on 30-31 July. Strong [SE] winds from a typhoon carried the ejecta to [an inhabited area] 10 km [NW of] the crater. Three persons were slightly injured, and [windowpanes] were broken in 62 houses and 45 cars. More than 50 earthquake swarms, each lasting several hours, occurred during July. . . .

Information Contacts: JMA, Tokyo.


September 1978 (SEAN 03:09) Citation IconCite this Report

Frequent explosions and continuous ash emission

. . . [There were] 32 recorded explosions from the summit crater of Minami-dake during August. The explosions produced ash clouds that rose about 2,000 m above the crater. Emission of . . . ash clouds was continuous between explosions. Ash fell every day around the volcano, primarily to the NW, causing slight damage to crops, electric wires, and homes over a broad area. Total August ashfall was estimated at a few centimeters (20 kg/m2) in a village 5 km from the volcano.

Information Contacts: JMA, Tokyo.


November 1978 (SEAN 03:11) Citation IconCite this Report

Explosions persist, but no damage reported

The summit crater of Minami-dake exploded 25 times in September and 15 times in October. Since June, dense ash clouds have frequently been emitted from Minami-dake between recorded explosions. Ashfalls near the volcano were almost continuous June-October, damaging . . . crops, and impeding traffic. However, there was no damage from coarse tephra as in late July nor from explosion air shocks, which broke [windowpanes] in late May.

Information Contacts: JMA, Tokyo.


December 1978 (SEAN 03:12) Citation IconCite this Report

Only one explosion in November; ash ejection between explosions ends

Only one explosion from the summit crater of Minami-dake was recorded during November, on the 15th. The ash ejection that had frequently occurred between explosions since the spring ended about 25 November. Activity has been limited to steam emission since then.

Further Reference. Kamo, K., 1979, The Recent Activity of Sakura-jima Volcano; in Report on Volcanic Activities and Volcanological Studies in Japan for the Period from 1975 to 1978; Bulletin of the Volcanological Society of Japan, v. 24, no. 4, p. 26-34.

Information Contacts: JMA, Tokyo.


January 1979 (SEAN 04:01) Citation IconCite this Report

Number of explosions increase; lapilli cracks airplane windows

Eleven explosions from the summit crater of Minami-dake were recorded in December. The number of explosions in 1978 was 231, little changed from 223 in 1977. Lapilli ejected on 4 December cracked 2 windshields of All Nippon Airways airplanes. Similar damage to aircraft above Sakura-jima occurred 8 April 1975 and 25 December 1977.

Information Contacts: JMA, Tokyo.


February 1979 (SEAN 04:02) Citation IconCite this Report

Explosions continue, but less tephra than last autumn

Fifteen explosions from the summit crater of Minami-dake were recorded during January (figure 4). On 5 January, lapilli broke [windshields] in seven cars. Ash emission was observed between explosions, but not as frequently as in the autumn of 1978.

Figure (see Caption) Figure 4. Summary table of explosions from Minami-dake crater at Sakura-jima, 1979. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


March 1979 (SEAN 04:03) Citation IconCite this Report

New dome emplacement in December

Sixteen explosions occurred from the summit crater of Minami-dake during February. Ash emission between explosions remained infrequent, as it has since December. Yosihiro Sawada reports that high-amplitude volcanic tremor ended in November 1978, and shallow B-type earthquakes began to be recorded. An earthquake swarm in mid-December preceded the emplacement of a new incandescent lava [mound] on the [crater] floor of Minami-dake, after which explosions became more frequent.

Information Contacts: JMA, Tokyo; Y. Sawada, MRI, Tokyo; D. Shackelford, CA.


April 1979 (SEAN 04:04) Citation IconCite this Report

Number of explosions drops

Seven explosions from the summit crater of Minami-dake were recorded in March. Tephra from the explosions caused no damage.

Information Contacts: JMA, Tokyo.


May 1979 (SEAN 04:05) Citation IconCite this Report

Lava dome growing; explosions persist

Seven explosions from the summit crater of Minami-dake were recorded in April. Reflected glow was observed above the crater on 22 April. Earthquake swarms . . . were frequently recorded in April, indicating that the andesitic lava [mound] in the bottom of the crater was increasing in volume. The strongest explosions of the current eruption have taken place during periods when the lava dome was most voluminous.

Information Contacts: JMA, Tokyo.


June 1979 (SEAN 04:06) Citation IconCite this Report

First explosion-free month in 6 years

No explosions from the summit crater of Minami-dake were recorded during May, the first time in 6 years that a month without explosions has occurred there [but see 4:9]. Sakura-jima's current eruption began in October 1955.

Information Contacts: JMA, Tokyo.


July 1979 (SEAN 04:07) Citation IconCite this Report

Second explosion-free month

For the second consecutive month, no explosions from the summit crater of Minami-dake were recorded in June. The last explosions occurred on 30 April. Sakura-jima's current eruption has included several quiet phases, the most recent from December 1972 to April 1973.

Information Contacts: JMA, Tokyo.


August 1979 (SEAN 04:08) Citation IconCite this Report

No new explosions; activity since 1972 summarized

No explosions have occurred from Sakura-jima since [two were recorded on] 30 April, a long quiet phase for this eruption.

Information Contacts: JMA, Tokyo.


September 1979 (SEAN 04:09) Citation IconCite this Report

Explosions resume after 110-day hiatus

The following is a report from Manabu Komiya. "Sakura-jima exploded on 19 August after 110 days of quiescence, producing an ash cloud 1 km high. It was the 46th explosion of this year. Five more explosions occurred in early September, but none caused any damage. The fact that no explosion had occurred in 110 days does not immediately suggest decreasing volcanism, because intermittent ash emission without explosive shocks had occurred through the explosion-free period, as frequently as before. Daily ash emission often caused ashfalls at cities and towns near the volcano. Volcanic gas that flowed down the flanks damaged vegetation, adding to the damage caused by falling ash. Reflected glow above the crater was often observed at night during July and early August. Swarms of B-type earthquakes . . . (one burst consisted of hundreds of earthquakes) were recorded a few times per month in June and August. These facts indicate that the lava mound on the crater floor persisted or grew during this period. An aerial inspection on 30 July revealed a large mound that had reached a volume of 7 x 103 m, twice that of May."

Information Contacts: JMA, Tokyo.


October 1979 (SEAN 04:10) Citation IconCite this Report

Explosions continue

Thirteen explosions were recorded in September. The highest eruption cloud rose 2.8 km above the crater, on 8 September (see table 3 below). No damage from any of the explosions was reported.

Information Contacts: JMA, Tokyo.


November 1979 (SEAN 04:11) Citation IconCite this Report

Explosion frequency doubles; aircraft damaged

Explosions recorded at the JMA's Kagoshima Observatory, 11 km from Sakura-jima, were about twice as frequent in October and November as they were in September. Typically, an "explosion" consisted of a weak shock, registered both seismically and sonically, followed by ash ejection. Ash emission without an accompanying explosion occurred more often than the explosion-triggered events.

[The explosion at 1400 on 10 November was followed by about 20 minutes of tephra emission and continuous tremor.] Lightning was frequent in the tephra cloud, which deposited 2 cm of ash during a rainstorm at Furosato, 3 km from the crater. Lapilli cracked a car windshield and two cars collided after skidding on the wet ash.

The windshields of two domestic airliners were cracked as they flew into an eruption cloud near Sakura-jima at 0801 and 0805 on 18 November, about 20 minutes after a recorded explosion. In both cases, damage was restricted to the outermost of three sheets of glass, and the planes landed safely. Another 2 cm of ash fell at Furosato after this explosion.

Information Contacts: JMA, Tokyo.


December 1979 (SEAN 04:12) Citation IconCite this Report

Frequent explosions continue; tephra cracks another airplane windshield

Frequent explosions and ejections of dense ash clouds continued through December. Between 28 November and 28 December, 36 explosions were recorded at the JMA's Kagoshima Observatory. The 110-day explosion-free period of 1 May-18 August dropped the number of recorded explosions in 1979 to [149], from 231 in 1978 and 223 in 1977. However, the monthly totals for October-December 1979 are higher than the 1977-78 averages.

The windshield of a domestic YS-11 airliner was cracked by tephra at 1.5 km altitude at 1749 on 24 December, 9 minutes after an explosion from Sakura-jima. The plane landed safely at Kagoshima airport 7 minutes later.

Information Contacts: JMA, Tokyo.


January 1980 (SEAN 05:01) Citation IconCite this Report

Explosions continue; activity since 1955 summarized

Thirty-six explosions were recorded in December by the JMA's Kagoshima Observatory (table 3), bringing the total number in 1979 to 149. Tephra cracked airplane windshields on 18 and 24 December; both planes landed safely. In January, 10 explosions had been recorded by the 27th, none of which caused any damage.

Table 3. Explosions recorded at the Kagoshima Observatory, 19 August 1979-27 January 1980. Data courtesy of JMA.

Date Time Cloud Height (km) Activity
19 Aug 1979 -- 1.0 --
03 Sep 1979 -- -- --
07 Sep 1979 -- 1.2 --
08 Sep 1979 -- 2.8 --
09 Sep 1979 -- 0.8 --
10 Sep 1979 -- -- --
04 Oct 1979 0555 1.2 --
08 Oct 1979 1025 1.2 --
09 Oct 1979 0907 -- --
10 Oct 1979 0900 2.0 --
11 Oct 1979 0240 -- --
11 Oct 1979 1408 2.0 --
12 Oct 1979 0012 -- --
12 Oct 1979 2116 -- --
13 Oct 1979 0310 -- --
14 Oct 1979 0623 1.6 --
14 Oct 1979 1321 -- --
14 Oct 1979 1957 -- --
14 Oct 1979 2247 -- --
15 Oct 1979 1403 1.2 --
16 Oct 1979 0550 1.3 --
16 Oct 1979 0751 1.5 --
16 Oct 1979 1658 -- --
16 Oct 1979 1846 -- --
17 Oct 1979 2245 -- --
18 Oct 1979 0509 -- --
18 Oct 1979 1559 -- --
23 Oct 1979 1346 2.5 --
26 Oct 1979 1503 2.7 --
27 Oct 1979 0204 -- --
30 Oct 1979 1655 2.0 --
02 Nov 1979 0246 -- --
03 Nov 1979 1038 -- --
04 Nov 1979 0804 -- --
08 Nov 1979 0807 1.5 --
09 Nov 1979 1054 -- --
10 Nov 1979 0148 -- --
10 Nov 1979 1400 -- --
10 Nov 1979 1815 -- --
14 Nov 1979 0410 -- --
14 Nov 1979 1513 2.3 --
15 Nov 1979 1623 -- --
16 Nov 1979 0156 -- --
18 Nov 1979 0742 -- Two airplane windshields cracked.
19 Nov 1979 1733 1.8 --
20 Nov 1979 1514 2.3 --
20 Nov 1979 1522 2.7 --
20 Nov 1979 1536 2.0 --
21 Nov 1979 1458 1.6 --
21 Nov 1979 1646 1.7 --
21 Nov 1979 1806 -- --
21 Nov 1979 1920 -- Incandescent cinders.
22 Nov 1979 2106 -- --
24 Nov 1979 0834 1.0 --
24 Nov 1979 1955 -- Incandescent cinders, lightning.
27 Nov 1979 2237 -- --
28 Nov 1979 0209 -- --
28 Nov 1979 1305 2.0 Lightning.
29 Nov 1979 0142 -- --
01 Dec 1979 0210 -- --
01 Dec 1979 0435 -- --
04 Dec 1979 0824 0.8 --
04 Dec 1979 1630 1.0 Lightning.
10 Dec 1979 0352 -- --
11 Dec 1979 0147 1.5 --
12 Dec 1979 0516 -- --
13 Dec 1979 0942 1.5 --
14 Dec 1979 1512 1.4 --
14 Dec 1979 1547 2.4 --
15 Dec 1979 1247 1.3 --
15 Dec 1979 1944 -- --
16 Dec 1979 0002 -- --
17 Dec 1979 0038 -- --
17 Dec 1979 0153 -- Lightning, three incandescent columns, rumbling.
17 Dec 1979 2219 -- Incandescent column.
18 Dec 1979 2118 -- Reflected glow after explosion.
19 Dec 1979 2307 -- --
21 Dec 1979 0135 -- --
22 Dec 1979 0119 -- --
23 Dec 1979 1138 -- --
23 Dec 1979 1540 -- Rumbling.
23 Dec 1979 1812 -- --
23 Dec 1979 2007 -- Rumbling.
24 Dec 1979 1710 1.7 --
24 Dec 1979 1740 2.3 Lightning.
24 Dec 1979 2218 -- Two 400-m incandescent columns, lasting 20 seconds; much lightning.
24 Dec 1979 2227 -- Much lightning.
24 Dec 1979 2231 -- Much lightning.
25 Dec 1979 1059 0.8 Lightning.
26 Dec 1979 0827 2.0 --
26 Dec 1979 1033 2.1 --
26 Dec 1979 1049 2.1 Lightning.
27 Dec 1979 0733 1.0 --
27 Dec 1979 0915 1.7 --
28 Dec 1979 1151 2.0 --
08 Jan 1980 1400 2.0 --
10 Jan 1980 0929 2.5 --
10 Jan 1980 1049 2.0 --
18 Jan 1980 1322 1.2 --
19 Jan 1980 0550 -- --
22 Jan 1980 2335 -- --
23 Jan 1980 2216 -- --
24 Jan 1980 1656 1.0 --
24 Jan 1980 1707 1.3 --
27 Jan 1980 0828 1.6 --

Information Contacts: JMA, Tokyo.


April 1980 (SEAN 05:04) Citation IconCite this Report

Explosions and incandescent tephra

Twenty explosions from Sakura-jima were recorded in February and 10 in March (figure 5), none of which caused any damage. Ash emission without explosions occurred less frequently in February and March than has been usual over the past 5 years.

Figure (see Caption) Figure 5. Summary table of explosions from Minami-dake crater at Sakura-jima, 1980. Data courtesy of JMA.

Two bursts of B-type earthquakes were recorded in the 2-month period. About 1,000 events occurred in 11 hours on 13 February and about 500 in 5 hours on 15 March. Both of these bursts, thought by JMA geologists to be caused by magma rising in the vent, were followed by increased explosion activity. In addition, columns of incandescent tephra were ejected after the February earthquakes. On 14 February, two columns rose 200 m at 0438 and a 400-m column was ejected at 2137.

Activity beginning late 15 February was typical of the more prolonged eruptive periods that have characterized Sakura-jima since explosions resumed in August 1979. Soon after a loud explosion at 2241, two columns of incandescent tephra rose 200 m above the summit. Ejection of incandescent blocks was almost continuous until about midnight, then occurred every few minutes until 0110 on the 16th. Lapilli up to 3 cm in diameter fell on inhabited areas, but caused no damage. Much lightning was seen in the eruption clouds. Strong, continuous air vibrations rattled windows in towns at the base of the volcano. A seismograph recorded strong tremor until about 0100 on 16 February. By about 0300, eruptive activity had declined, and vapor emission or weak ash ejection continued until the 9 March explosion.

Information Contacts: JMA, Tokyo.


May 1980 (SEAN 05:05) Citation IconCite this Report

Largest number of explosions/month in five years

A total of 48 explosions from Sakura-jima were recorded in April, the largest monthly figure in 5 years. Frequent explosions continued into early May. Four of the April explosions produced ash clouds higher than 2 km, and two ejected incandescent columns. No damage was reported.

Information Contacts: JMA, Tokyo.


June 1980 (SEAN 05:06) Citation IconCite this Report

Activity declines. Explosions/month tabulated since 1955

The period of unusually frequent explosions at Sakura-jima that began in late March ended on 7 June. In May, 69 explosions were recorded, the third highest monthly total since the eruption began in October 1955. Most of the May and June explosions produced ash clouds that rose 1-2 km above the crater; the highest clouds were 2.5 km on 17 May and 2.7 km on 7 June. A 100 m-high incandescent column was observed at night on 1 May.

Ash emission without an explosion [shock] has also more frequent than usual from late March through early June. Ash often fell on Kagoshima, causing various minor disruptions. Fallen ash derailed a streetcar on 2 May, and electric power for 3,700 homes was cut off on 8 May after wet, sticky ash caused numerous short circuits. During a heavy rainfall on 12 May, a debris flow damaged a concrete bridge at the foot of the volcano. Ash emission declined in mid and late June.

Information Contacts: JMA, Tokyo.


July 1980 (SEAN 05:07) Citation IconCite this Report

More frequent explosions

After a decline from 69 explosions in May to 12 in June, activity remained at a similar level until late July, when explosions became stronger and more frequent. The last July explosion was also the month's largest. A tephra cloud rose about 3 km, and [blocks fell onto] the lower half of the volcano. Ash fell to the NE, reaching [the city of] Miyakonojo, 40 km away, one hour after the explosion. No damage was reported.

Information Contacts: JMA, Tokyo.


August 1980 (SEAN 05:08) Citation IconCite this Report

More frequent explosions

The number of recorded explosions increased from 16 in July to 34 in August. The highest August eruption cloud rose 2 km above the summit, on the 2nd. Ash frequently fell NE of the volcano but no damage was reported. . . .

Information Contacts: JMA, Tokyo.


September 1980 (SEAN 05:09) Citation IconCite this Report

Explosions continue

During September, 21 explosions were recorded. The highest September ash cloud rose 1800 m on the 7th. Blocks fell on the flanks on several occasions. A 200-m-high incandescent column lasted for 10 seconds on 30 September. No damage was reported from the September activity.

Information Contacts: JMA, Tokyo.


November 1980 (SEAN 05:11) Citation IconCite this Report

Lapilli and air shocks break windows

The number of recorded explosions declined from 21 in September to four in October, then increased to 21 in November. The highest October ash cloud reached 2.0 km, on the 1st. None of the October activity caused any damage. Lapilli from the largest November tephra cloud, which rose 2.5 km on the 8th, broke five car windshields. The air shock from the 28 November explosion broke two [windowpanes] in a hotel at the base of the volcano. No injuries were reported.

Information Contacts: JMA, Tokyo.


December 1980 (SEAN 05:12) Citation IconCite this Report

Explosions continue; 1980 activity summarized

Explosions from the summit crater of Minami-dake were continuing at the end of 1980. The nine explosions in December brought the year's total to 276, the largest number since 362 were recorded in 1974. The highest December ash cloud rose 1.8 km on the 3rd. Airshocks and tephra fall from the explosions broke [windowpanes] in buildings, automobiles, and aircraft; disrupted traffic; and interrupted electric power on occasion in 1980; but caused no injuries.

Information Contacts: JMA, Tokyo.


January 1981 (SEAN 06:01) Citation IconCite this Report

Earthquake swarm followed by glow and explosions

A burst of B-type earthquakes that began at 0200 on 18 January prompted the JMA observatory at Sakura-jima to issue an explosion warning at 0930. Reflected glow was seen over the summit that night. Four strong explosions occurred during the next two days (figure 6). Each of the first three produced a 200-m-high incandescent column. The fourth, strongest explosion at 1632 on 20 January ejected an incandescent block that formed a 1.3-m-diameter crater when it fell near an inhabited area. Similar occurrences of B-type earthquake bursts, reflected glow of the lava mound in the crater, and explosions were observed in July and August 1979. None of the January explosions caused any damage.

Figure (see Caption) Figure 6. Summary table of explosions from Minami-dake crater at Sakura-jima, 1981. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


February 1981 (SEAN 06:02) Citation IconCite this Report

Fewer explosions

After an active month in January, only five explosions [occurred] in February (figure 6). The highest February ash cloud rose 1.2 km on the 21st. The February explosions caused no damage.

Information Contacts: JMA, Tokyo.


March 1981 (SEAN 06:03) Citation IconCite this Report

Explosions; two incandescent columns

Eleven explosions occurred in March. The highest ash cloud grew to 2 km on the 18th. Two incandescent columns rose simultaneously from vents in the summit crater of Minami-dake on the 20th. No damage was reported.

Information Contacts: JMA, Tokyo.


April 1981 (SEAN 06:04) Citation IconCite this Report

Fewer explosions

Activity declined in April. Only two explosions, on 1 and 21 April, had been recorded by the 27th.

Information Contacts: JMA, Tokyo.


May 1981 (SEAN 06:05) Citation IconCite this Report

Explosions; ash ejection: B-type earthquakes

After only two explosions from the summit crater of Minami-dake had occurred in April, none were recorded in May until the 18th. As of 28 May, four explosions had occurred. The largest produced a 1.2-km-high ash cloud on the 24th. Although explosive activity was limited in April and May, there was continued ash ejection during which explosions were not registered at the JMA's Kagoshima Observatory. Bursts of B-type earthquakes were recorded on 3, 5, 18, and 19 May.

Information Contacts: JMA, Tokyo.


June 1981 (SEAN 06:06) Citation IconCite this Report

Fewer explosions

Activity has declined since April. Only three explosions, on 1, 8, and 14 June, had been recorded by 28 June. None caused damage. The highest ash cloud rose 2.5 km on 8 June.

Information Contacts: JMA, Tokyo.


July 1981 (SEAN 06:07) Citation IconCite this Report

Explosions decline; seismic and eruptive activity since 1978 summarized

During the first 27 days of July, only one explosion from the summit crater of Minami-dake was recorded by the JMA's Kagoshima Observatory. Ash ejection without recorded explosions and local seismicity also remained at low levels through July. Activity since January 1978 is summarized in figure 7.

Figure (see Caption) Figure 7. Activity at Sakura-jima during January 1978-June 1981, showing monthly number of recorded explosions (A), large ash clouds (B), recorded earthquakes (C), days when ashfall was observed at the Japan Meteorological Agency's Kagoshima Observatory, (D, black bars), and monthly volume of ash at Kagoshima Observatory (D, white bars). Ashfall is measured in a tray at Kagoshima Observatory. Explosions are counted by visual observation, microbarographs, and seismometers. Courtesy of JMA.

Information Contacts: JMA, Tokyo.


August 1981 (SEAN 06:08) Citation IconCite this Report

Explosions increase

The decline in activity first noted in April reversed in August, when 34 explosions were recorded. Only one was recorded in July. Most of the explosions were small. The largest eruption cloud reached 2.5 km on 26 August. Ash frequently fell NE of the volcano, but no damage was reported. Weak glow was seen above the active crater on 13, 24, and 31 July.

Information Contacts: JMA, Tokyo.


September 1981 (SEAN 06:09) Citation IconCite this Report

Frequent explosions, mud-like ejection

Frequent explosions from the summit crater of Minami-dake continued through September, after increasing from one in July to 34 in August. None of the 38 recorded in September caused any damage. Ash clouds higher than 2 km above the summit were observed on 13, 14, 18, 20, and 23 September. On the 13th an ash cloud that rose to 2.6 km was ejected simultaneously with [dense powder] that covered a 100 x 100 m area on the W slope of the active crater. The highest cloud rose to 2.7 km, also on the 13th.

Information Contacts: JMA, Tokyo.


October 1981 (SEAN 06:10) Citation IconCite this Report

Frequent explosions, two incandescent columns

Frequent explosions continued through October, when 35 were recorded. Two 100-m-high incandescent columns were recorded for 3 seconds at 0444 on 2 October. Ash clouds higher than 2 km above the summit were observed on 3, 17 and 31 October.

Information Contacts: JMA, Tokyo.


November 1981 (SEAN 06:11) Citation IconCite this Report

More frequent explosions; tephra breaks windshields

Eruptive activity intensified in November. Explosions became more frequent and stronger; 50 were recorded. The explosion rate had been about 35/month August-September, but fewer than 4/month April-July. An explosion at 1528 on 16 November ejected incandescent tephra that caused [grass fires] on the SW flank. The [eruption] column rose 3 km, the greatest height this year. Lapilli from an explosion at 1322 on 21 November broke windshields on a few cars passing 3 km S of the summit crater of Minami-dake. Incandescent columns were observed on several occasions: 100 m high for 5 seconds on 7 and 22 November, and for 3 seconds on 14 and 29 November; 200 m high for 3 seconds on 30 November.

Information Contacts: JMA, Tokyo.


December 1981 (SEAN 06:12) Citation IconCite this Report

Notable explosions of 1981 tabulated

The rate of explosive activity at the summit crater of Minami-dake dropped slightly in December; 27 explosions had been recorded by the 25th. Incandescent columns 200 m high were observed for 7 seconds at 1836 on 9 December and for 5 seconds at 0622 on 22 December. Ash clouds higher than 2 km were observed on 3, 4, and 9 December.

Information Contacts: JMA, Tokyo.


January 1982 (SEAN 07:01) Citation IconCite this Report

Frequent explosions continue

Since last August, explosions from the summit crater of Minami-dake have been frequent. In January, 27 explosions were recorded (figure 8). A 200-m-high incandescent column lasting 3 seconds was observed on 20 January, and another 300 m high for 5 seconds on the 21st.

Figure (see Caption) Figure 8. Summary table of explosions from Minami-dake crater at Sakura-jima, 1982. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


March 1982 (SEAN 07:03) Citation IconCite this Report

Frequent explosions; B-type earthquakes

The rate of explosions from the summit crater of Minami-dake declined in early and mid-February, then increased late in the month. Frequent explosions continued through March. Recorded explosions numbered 15 in February, 47 in March.

On 26 February, an explosion at 1044 produced a 1,600-m-high eruption column, then a continuous ash cloud was observed until 1150, and from 1430 until sunset ended visual observation from the JMA's Kagoshima Observatory. A 1,500-m-high eruption column was ejected at 1731. On 28 February a continuous ash cloud was observed 0620-1230, and three explosions were recorded the next day. On 24 March a 100-m-high incandescent column was observed for 15 seconds, and on the 28th a 200-m-high incandescent column lasting 30 seconds was accompanied by rumbling. Local seismicity was active in the first half of February, when explosive activity had declined. JMA scientists have observed that a swarm of B-type earthquakes, which they interpret as possibly caused by magma rising to a shallower depth, is often followed by increased explosive activity. In March local seismic events and continuous ash clouds were frequently observed, but only rarely did an explosion with a large amount of ejecta occur. There was some damage to nearby farm products.

Information Contacts: JMA, Tokyo.


April 1982 (SEAN 07:04) Citation IconCite this Report

Explosion rate declines; gas damages crops

Recorded explosions declined from 47 in March to 15 in April. Ash clouds higher than 2,000 m were observed on 12 and 19 April. These two explosions ejected incandescent blocks, but no damage was reported. In February and March, volcanic gas . . . damaged farm crops at the SW foot of the volcano.

Information Contacts: JMA, Tokyo.


May 1982 (SEAN 07:05) Citation IconCite this Report

Incandescent tephra, ashfall

The number of recorded explosions from the summit crater of Minami-dake was 24 in May. After mid-May, most explosions ejected incandescent tephra, but no damage was reported. In late May activity gradually changed to continuous ash ejection without recorded explosions. Wind carried ash toward the W, causing heavy ashfall in and around the city of Kagoshima, on 25-26 May. The explosion on 19 May, at 0727, produced an eruption column higher that 2,500 m and was associated with 30 seconds of rumbling. Incandescent columns were observed on several occasions: 400 m high for 8 seconds on 4 May; 200 m high for 3 seconds on 5 May and for 5 seconds on 24 May.

Information Contacts: JMA, Tokyo.


June 1982 (SEAN 07:06) Citation IconCite this Report

Frequent explosions; tephra cause minor damage

The number of explosions from the summit crater of Minami-dake increased from [24] in May to 34 in June. A 300-m-high incandescent column was observed at 2223 on 8 June, and the highest plume rose 3000 m above the summit on 10 June. Carried by a strong wind, ejecta from the explosion at 0325 on 14 June fell in the area between Kurokami (4.7 km E of the crater) and Sakura-jima-guchi (5.5 km SE). At Kurokami, lapilli broke a car windshield and a building's windowpane.

Information Contacts: JMA, Tokyo.


August 1982 (SEAN 07:08) Citation IconCite this Report

Explosive activity increases then declines; debris flow

Thirteen explosions were recorded in July. Activity was low during the first half of the month, then increased 16-24 July. A debris flow [caused by rainfall] carried away a concrete bridge at the S base of the volcano on the 24th. After the 24 July explosion, activity changed to continuous ash ejection without explosion [shocks].

In August, 14 explosions were recorded. Activity continued at the July level. On 24 August, continuous ash ejection without explosion [shocks] began in the morning, causing heavy ashfall to the NW. Ashfall from 1415-1500 was measured at 285 g/m2 at the JMA's Kagoshima Observatory (about 10 km W of the crater). At the Kagoshima Prefecture Office, 2 km N of the JMA Observatory, 5522 g/m2 of ash fell from 0900-1600. The ejection declined in the evening. The ash caused slight damage.

Information Contacts: JMA, Tokyo.


November 1982 (SEAN 07:11) Citation IconCite this Report

Explosions decline, but plane encounters plume

Explosive activity at the summit crater of Minami-dake and local seismicity have declined since September. Two explosions were recorded in September, 6 in October, and 4 in November. An explosion at 1130 on 17 September was followed by continuous ash ejection, without explosion [shocks], lasting for 98 minutes and resulting in heavy ashfall on the S half of the city of Kagoshima, about 15 km NW. In October, ash ejection occurred every day, although few explosions were recorded. The frequent ash ejection was accompanied by an increase in the number of recorded tremor events, which totaled 334 hours in October.

Each of the November explosions produced lapilli ejection, air shocks, and sounds. At 1523 on 23 November, the largest explosion of the 3-month period sent an eruption cloud to 3 km. The cloud was observed from the JMA's Miyakonojo Weather Station, 45 km ENE. An Air Nauru jet carrying 39 passengers and flying at about 3 km altitude entered the cloud 23 km ESE of Sakura-jima at 1545, 6 minutes after leaving Kagoshima Airport. The impact of the lapilli produced hairline cracks in three cockpit windows, prompting the pilot to return to Kagoshima, where he landed safely. At the SE foot of the volcano, a car windshield was destroyed.

Information Contacts: JMA, Tokyo; UPI.


December 1982 (SEAN 07:12) Citation IconCite this Report

Frequent explosive activity, ash ejection; little ash

Explosive activity at the summit crater of Minami-dake intensified in December when 32 explosions were recorded. Only 12 had been recorded from September through November. Ash ejections lasting less than 25 minutes and not accompanied by instrument-recorded explosions were frequently observed. Although eruptive activity was frequent, large amounts of ejecta were rarely observed. No damage was reported. In early December, 124 hours of volcanic tremor were recorded but only 20 hours were recorded during the middle of the month, when explosive activity peaked.

Information Contacts: JMA, Tokyo.


January 1983 (SEAN 08:01) Citation IconCite this Report

Increased explosive activity, ash ejection

Activity at the summit crater of Minami-dake intensified in January; 54 explosions (figure 9) and 35 ash ejections not accompanied by instrument-recorded explosions were observed. In the second half of January, explosions were accompanied by larger amounts of lapilli. An explosion at 1059 on 26 January (table 4) ejected an eruption column that rose 3.8 km above the summit, the highest observed in the past 9 years. This cloud was large enough to be observed from JMA's Asosan Weather Station, 150 km to the NNE; aircraft crews reported that it rose 7.8 km above sea level. Lapilli from this explosion broke the windshield of a car passing near Arimura, 3 km S of the summit. Incandescent columns were observed during two of the explosions on 31 January. A 300-m-high column accompanied the explosion at 0228 and lasted 40 seconds; a column 200 m high lasted 30 seconds during the 0545 explosion.

Figure (see Caption) Figure 9. Summary table of explosions from Minami-dake crater at Sakura-jima, 1983. Data courtesy of JMA.

Table 4. Notable eruptive activity of Sakura-jima, 1983. Courtesy of JMA.

Date Event Comment
26 Jan 1983 Explosion at 1059 Windshields broken on 4-5 cars at SE foot.
02 Feb 1983 Debris flows One flow damaged nine houses and a hotel at S foot after pushing away part of a sand trap wall.
18 Feb 1983 Explosion at 1326 Ejected blocks as large as 0.5-1 m; one hut at SE foot burned.
21 Feb 1983 Explosion at 1043 Windshields broken on four cars at SE foot.
02 Mar 1983 Debris flows Road at S foot temporarily covered.
22 May 1983 Explosion at 1237 Eruption column at 4 km above the summit, 2 hours of continuous ash ejection; electric supply interrupted, equipment damaged at Kurokami, 5 km E.
26 May 1983 Explosion Five hours of continuous ash ejection; windshields broken on 23 cars, gymnasium roof cracked.
24 Jul 1983 Three explosions Strong SW wind carried ash to Miyazaki City, 80 km NE, reducing visibility to 4 km.
02 Aug 1983 Explosion at 1401 Large amount of lapilli fell near Karutayama Volcano Observatory, about 3 km NW, and at site of sand trap construction, 2 km SE, where four workers were slightly burned.
14 Aug 1983 Explosion at 1614 Windshields on 16 cars, windows in two houses, and a hut roof broken at Nojiri (SW foot); windshields on three cars broken in Kamoike (S part of Kagoshima City, 10 km WSW).
27 Aug 1983 Explosion at 1401 Car windshields broken at Arimura, 3 km S.
01 Sep 1983 Debris flows Roads temporarily closed. Total of five flows (on 1, 10, 20, and 21 September).
17-18 Sep 1983 Continuous ash ejection Ash on track derailed streetcar in N Kagoshima City, 10 km WNW
20 Sep 1983 Explosion at 1518 A few windows in a temple damaged at Kamoike. Debris flows (see 1 Sep comment).
10 Oct 1983 Explosion at 1351 Windshields broken on two cars at SW foot.
07 Dec 1983 Explosion at 1702 Car windshield broken in Tarumizu City, 10 km SSE.
13 Dec 1983 Explosion at 1028 Large air shock broke windows in hotel and house.

Information Contacts: JMA, Tokyo.


February 1983 (SEAN 08:02) Citation IconCite this Report

Increased explosive activity; rain-caused debris flows

The rate of explosions at the summit crater of Minami-dake has gradually increased since December. In January, 53 were recorded and in February, 73 explosions were recorded, one of the larger monthly totals since the eruption began in 1955.

Ashfall and eruption clouds were observed on 11, 14, and 27 February at Miyakonojo Observatory. The air shock from the explosion at 2241 on 5 February was large enough to be felt at Miyazaki Observatory, 80 km NE. On 18 February a hut at Arimura, 3 km SSE of the summit, was set on fire by an incandescent block, 50-100 cm in diameter. The explosion at 1043 on the 21st was not large enough to be accompanied by any observed explosive sound or felt air shock at Kagoshima Observatory but strong NW winds carried lapilli toward the SE foot of the volcano where 4 car windshields were cracked or broken. Two incandescent columns, rising about 200 m above the crater, were observed in February for 10 seconds on the 1st, and for 5 seconds on the 27th.

Rain on 2 February triggered debris flows in S flank valleys. One flowed into nine houses and a hotel after pushing away a 10-m-long sand-trap wall, and covered the adjacent road for about 50 m. The monthly number of recorded seismic events was 4,456 in January, but decreased to 2410 in February.

Information Contacts: JMA, Tokyo.


April 1983 (SEAN 08:04) Citation IconCite this Report

Explosion rate, seismicity decline; lapilli ejected

The number of recorded explosions from the summit crater of Minami-dake declined to [36] in March and 22 in April. Observers saw lapilli ejected by about 1/4 of the explosions in March and 1/3 in April, but no damage was reported. The monthly number of recorded seismic events, including tremors, was 1,358 in March and 768 in April. On 2 March, rain-triggered debris flows in S and E flank valleys temporarily blocked a road.

Information Contacts: JMA, Tokyo.


May 1983 (SEAN 08:05) Citation IconCite this Report

Explosions and large plumes; windshields broken

The number of explosions from the summit crater of Minami-dake recorded in May was 22, the same as in April. In the second half of May, most of the explosions ejected lapilli and sent ash and vapor to more than 2 km above the summit. The 4.4-km-high [eruption] column from an explosion at 1320 on 18 May was one of the largest since the eruption began in 1955. On 22 May an explosion at 1237 that sent a column to more than 4 km was followed by 2 hours of continuous ash and vapor ejection. The activity was accompanied by thunder and temporary interruption of electric and telephone service. Ash fell as far as Aburatsu, on the E coast of Kyushu, 70 km E of the volcano. An explosion on 26 May was also accompanied by continuous ash ejection. A large amount of ash fell SSE of the volcano; more than 20 car windshields were broken, and the roof of a primary school cracked.

Information Contacts: JMA, Tokyo.


July 1983 (SEAN 08:07) Citation IconCite this Report

Explosions, tephra emission, and seismicity

In June, 33 explosions were recorded from the summit crater of Minami-dake and 31 in July. Although the explosion rate from June to mid-July was above its usual level, rarely was a large amount of ejecta observed in any explosion. Only about 1/8 of the explosions ejected much lapilli, or produced eruption columns that rose to more than 2 km above the summit.

Activity intensified slightly 19-24 July. Most explosions produced large amounts of ejecta and ash frequently fell on the cities of Miyakonojo (40 km ENE) and Miyazaki (80 km NE). The end of explosive activity on 25 July was followed by continuous ash ejection. Bad weather limited visual observation, but volcanic tremor that was assumed to be accompanied by ash ejection was recorded until 29 July. The number of large B-type earthquakes suddenly increased at about 1800 on 29 July and remained high until 0300 the next day. Earthquake size then returned to its usual level, but the recorded events were still more numerous than usual.

Explosive activity resumed on 31 July, accompanied by a decrease in seismic activity. An explosion at 1445 on 2 August ejected large amounts of lapilli, which fell near Kyoto University's Sakura-jima Volcano Observatory (about 1.7 km SW of the summit) and the site of sand trap wall construction, where 1 worker [originally reported as 4] was slightly burned. [Blocks] made many craters [near the University Observatory and the construction site]; the largest was 1.5 m in diameter and 1 m deep [produced by a block 50 cm in diameter].

Information Contacts: JMA, Tokyo.


December 1983 (SEAN 08:12) Citation IconCite this Report

Tephra from strong explosions damage cars and buildings

Recorded explosive eruptions from the summit crater of Minami-dake were frequent in August [33] and September (36), fewer in October (21) and November (16). In mid-August strong wind carried a large amount of ejecta to the inhabited area around the volcano, damaging cars and houses. On 14 August lapilli as large as 6-7 cm in diameter fell on Nojiri, at the foot of Sakura-jima 4 km SW of Minami-dake, breaking or cracking windshields on 16 cars, a house windowpane, and the roof of a hut. Radio news from Kagoshima reported that windshields on three cars were cracked by lapilli as large as 1-3 cm in diameter at Tarumizu Wharf, on the S side of the city. An explosion at 0153 on 16 August scattered lapilli up to 2.5 cm in diameter between Mochiki and Yumoto (3.5 km SSW of Minami-dake), where windshields on 26 cars ware cracked.

Explosive activity remained at a high level in September. Incandescent blocks from an explosion at 1148 on 12 September started a flank [brush] fire. A heavy ashfall on 17-18 September deposited 270 g/m2 of ash at JMA's Kagoshima Observatory (table 5); a Kagoshima streetcar derailed on 19 September due to ash on the tracks. A large air shock from an explosion at 1518 on 20 September broke windows in Kagoshima, and another explosion at 1638 sent lapilli as large as 1 cm in diameter toward the N. Five debris flows moved down S flank valleys on 1, 10, 20, and 21 September. Bursts of discrete seismic events were frequent in September. Bursts on 19 and 28 September lasted for about 10 hours and included large events.

Table 5. Monthly ashfall measured at Kagoshima Observatory, 1983. Courtesy of JMA.

Month Ashfall (g/m2)
Jan 1983 16
Feb 1983 66
Mar 1983 [174]
Apr 1983 224
May 1983 121
Jun 1983 530
Jul 1983 209
Aug 1983 55
Sep 1983 297
Oct 1983 43
Nov 1983 [117]
Dec 1983 60

Information Contacts: JMA, Tokyo.


January 1984 (SEAN 09:01) Citation IconCite this Report

Lapilli damage car windshields; air shock breaks windows; 1983 explosions and ashfalls tabulated

Recorded explosive eruptions were fewer in October (21) and November (16), but about as frequent in December (37) as in August [33] and September (36). About 1/4 of October's explosions were accompanied by large quantities of ejecta. On 10 October, the last and strongest of explosions at 1001, 1131 and 1351 sent an eruption column to 2.5 km above the summit. A large amount of lapilli broke windshields on two cars at Nojiri and Mochiki, at the SW foot of the volcano about 4 km from the summit. Activity remained at a relatively low level from late October to mid November. In late November stronger explosions were again frequently observed. During the first 12 explosions in December, observers at the Kagoshima Observatory witnessed lapilli ejection. Ejecta from an explosion at 1702 on 7 December broke a windshield at Usine in Tarumizu City (10 km SSE). 0n 13 December an explosion at 1028 generated an air shock that broke five windows in a hotel and one in a house. There were 413 recorded explosions in 1983, the second largest annual total since the current eruption began in 1955.

Information Contacts: JMA, Tokyo.


March 1984 (SEAN 09:03) Citation IconCite this Report

Tephra causes minor damage

An explosion at Sakura-jima on 12 April at about 0940, the 95th in 1984, produced an eruption cloud that rose to 2.3 km (table 6). According to press reports, ejecta fell over half the volcano and broke windows at the foot.

Table 6. Damage caused by Sakura-jima eruptive activity in 1984.

Date Time Result
04 Jan 1984 1928 Lapilli broke car windshield at S foot of the volcano.
10 Jan 1984 1457 Air shock cracked a window at E foot.
11 Jan 1984 2140 Air shock cracked three windows.
08 Mar 1984 0724 Lapilli cracked car windshield.
19 Mar 1984 -- Debris flows reached E foot; no damage reported.
30 Mar 1984 1853 Large quantity of lapilli; forest fires started.
12 Apr 1984 0941 Strong air shock cracked three windows at the E and S foot, two windows in Kagoshima.
19 Apr 1984 -- Debris flows occurred.
29 Apr 1984 1800 Large quantities of incandescent ejecta started forest fires in more than 10 places; strong air shock broke a window in Kamoike. (Damage in Kagoshima is rare.)
04 May 1984 -- A windowpane was broken in Yasui.
08 May 1984 -- Air shock broke a hospital window at the SW foot.
23 Jun 1984 -- Heavy ashfall caused a traffic jam and interrupted electric service in Kagoshima.
03 Jul 1984 -- Strong air shock broke windowpanes at a junior high school and a house in Koike at the W foot. A Sakura-jima Volcano Observatory employee was injured by broken glass in Yokoyama at the W foot.
07 Jul 1984 -- A large amount of lapilli broke 11 car windshields and a house windowpane at the NE foot.
21 Jul 1984 -- A large amount of ejecta including pieces up to a few meters in diameter fell at the S foot. Incandescent fragments broke the roofs of 10 houses and a warehouse, burning some slightly. Telephone and electric service was interrupted for a few hours.
10-11 Oct 1984 -- Volcanic gas damaged farm crops at the SW foot.
20 Dec 1984 -- Lapilli broke a few car windshields at the S foot.

Information Contacts: Kyodo News Service, Tokyo; UPI.


May 1984 (SEAN 09:05) Citation IconCite this Report

Explosive activity continues at high level; debris flows

Explosive activity at the summit crater of Minami-dake continued at a higher level, January-April (figure 10). The average monthly number of recorded explosions was 27, including larger ones that caused damage.

Figure (see Caption) Figure 10. Summary table of explosions from Minami-dake crater at Sakura-jima, 1984. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


December 1984 (SEAN 09:12) Citation IconCite this Report

Summary of 1984 explosions and damage

The number of recorded explosions at Sakura-jima in 1984 declined during July-November, but increased in December. Eruptive activity at the summit crater of Minami-dake caused damage around the volcano throughout the year.

Information Contacts: JMA, Tokyo.


January 1985 (SEAN 10:01) Citation IconCite this Report

Explosions with strong air shocks; 1984 activity summary

Explosive activity at the summit crater of Minami-dake declined August-November, then increased in December when 59 explosions were recorded. An explosion at 1820 on 20 December was accompanied by an air shock powerful enough to have been recorded at Uwajima (260 km NE); ash and lapilli up to 2 cm in diameter fell on the road at the S foot and broke a car windshield. An explosion at 2132 on the 31st was accompanied by another strong air shock that broke 11 windowpanes in three of the hotels at the S foot. The rate of explosions decreased in January, when 20 were recorded. A strong air shock recorded at Uwajima, Nobeoka (140 km NE), Kumamoto (135 km N, and other places broke a windowpane in a S-foot hotel on 23 January.

Information Contacts: JMA, Tokyo.


February 1985 (SEAN 10:02) Citation IconCite this Report

Explosion lofts lapilli that break 43 windshields

An explosion at the summit crater of Minami-dake on 24 February at about 1030 ejected a plume to 4 km height. Lapilli 4-5 cm in diameter fell as far as 5 km SE of the crater, damaging 43 cars at the S foot and in Tarumizu City (5 km SE). Brush fires started by hot tephra quickly died. An air shock was recorded in Miyazaki, about 75 km to the NE. In the 4 hours after 1200, 140 swarm earthquakes were recorded.

Information Contacts: T. Tiba, National Science Museum, Tokyo; Kyodo News Service, Tokyo.


March 1985 (SEAN 10:03) Citation IconCite this Report

Strong explosions; lapilli cause damage

Explosive activity at the summit crater of Minami-dake intensified in February, when 35 explosions were recorded (figure 11). The largest, at 1030 on the 24th, ejected a plume to an altitude of more than 4 km and was accompanied by a strong air shock that saturated the microbarograph at the Kagoshima Observatory. A strong NW wind carried a large amount of lapilli toward the SE foot. Between Arimura (3 km SSE) and Ushinefumoto (6 km ESE, in the middle of the city of Tarumizu), 28 car windshields were broken. Tile or slate roofs on 53 houses were slightly damaged at Ushinefumoto, and a windowpane was broken at Arimura. The number of recorded explosions increased to 54 in March, although the number expelling a large amount of ejecta decreased. Swarms of volcanic earthquakes were observed on 4, 17, and 19 February and 2, 8-9, and 24 March. On 31 March, an explosion sent lapilli 4-5 cm in diameter toward the SE foot, where 4 car windshields were cracked.

Figure (see Caption) Figure 11. Summary table of explosions from Minami-dake crater at Sakura-jima, 1985. Data courtesy of JMA.

Information Contacts: JMA, Tokyo.


April 1985 (SEAN 10:04) Citation IconCite this Report

Vigorous explosions; pyroclastic flow

Activity remained at a high level in April, when 37 explosions were recorded, as compared to 35 in February and 54 in March. An explosion on 9 April at 1827 ejected a plume to 4 km above the crater, and was followed by 40 minutes of continuous ash emission and volcanic lightning. A small pyroclastic flow moved down the SW flank to about 600 m elevation. In the city of Kagoshima, ashfall began at 1840 and continued until around 0200 the next day. In the 24 hours beginning at 0900 on the 9th, ashfall at the Kagoshima Observatory was 1,608 g/m2, the largest daily total since measurements of ash deposits started in April 1969.

Another event of the same type occurred 13 April at 0722. The explosion earthquake was followed by continuous tremors, which gradually changed into a swarm of B-type earthquakes. Lapilli up to 1 cm in diameter fell on the foot, where four car windshields were cracked. On 3 May, Space Shuttle astronauts photographed a whitish, relatively diffuse plume that extended at least [50] km from Sakura-jima (figure 12).

Figure (see Caption) Figure 12. Photograph of Sakura-jima taken by Space Shuttle astronauts on 3 May 1984 (STS51B-52-74). A plume extends more than 50 km NW. Courtesy of Charles A. Wood.

Information Contacts: JMA, Tokyo; C. Wood, NASA, Houston.


June 1985 (SEAN 10:06) Citation IconCite this Report

Explosive activity and eathquakes decline

Explosive activity declined in May, when only 10 explosions were recorded. The number of recorded volcanic earthquakes and tremors also decreased, from 6,580 in April to 2,755 in May.

Information Contacts: JMA, Tokyo.


July 1985 (SEAN 10:07) Citation IconCite this Report

Frequent explosions; tephra damages nearby towns

The number of recorded explosions increased from 10 in May to 33 in June and 60 in July. Explosions caused damage on 8, 13, 16, 22, and 30 June and on 6, 10, and 21 July. Bombs fell on roads and farms, producing large craters. A bomb from an explosion on 8 June at 1316 made a 1-m-diameter crater in a road near a residential area. On 13 June lapilli up to 3 cm in diameter fell on the S foot, cracking windshields and solar water heaters on rooftops. Ash fell heavily that day at Kagoshima and closed railway crossings. After an explosion on 16 June at 1147, a bomb fell on a farm, producing a crater 4 m in diameter and 0.8 m deep. On 22 June at 1029 an ash cloud rose 3.5 km. The air shock from the explosion broke windows at a school near the foot of the volcano, and falling lapilli cracked a car windshield on the E foot. Windshields of cars at the S foot were cracked by falling lapilli from a 30 June explosion. Total June ashfall was 1,510 g/m2 at JMA's Kagoshima Observatory.

Observations of the eruption column heights and quantity of ejecta were prevented by bad weather in early July. Debris flows from the volcano on 2 July blocked roads at three places after a heavy rainfall. On 6 July at 1720 a bomb fell on a house 3 km from the crater, briefly setting it afire and making a 2-m hole in the roof; no casualties or injuries occurred. On 10 July, incandescent rocks fell on an inhabited area in Arimura, at the S foot. One broke into pieces and cracked roof tiles on a house.

An airshock from a 21 July explosion broke windowpanes of a high school and a restaurant in the central part of Kagoshima. The explosion was followed by continuous emission of ash, which was carried toward Kagoshima. Early the next day, a Japan National Railway crossing gate in the N part of the city malfunctioned because of ash deposits on the rails; a car was struck by a train, but the car's driver was only slightly injured. Debris flows on 27 July blocked a road and broke buried water pipes at the S foot.

Ashfall was observed daily at the Kagoshima Observatory in late July. During the 24 hours beginning 28 July at 0900, ashfall was 2,476 g/m2, the largest daily total, raising monthly and yearly totals to the largest since measurements of ash deposits started in April 1969.

On 31 July, three explosions with large eruption columns at 0700, 0848, and 0951 were followed by vigorous ash emission that continued until about 1200. Driven by a SE wind, the ash fell over the W coast of Kyushu (figure 13).

Figure (see Caption) Figure 13. Ashfall from 31 July 1985 explosions at Sakura-jima. Courtesy of JMA.

Information Contacts: JMA, Tokyo.


October 1985 (SEAN 10:10) Citation IconCite this Report

Explosive activity declines then increases

Explosive activity at the summit of Minami-dake declined in August, although vigorous ash emission was frequently observed. A large amount of ash fell on the city of Kagoshima, temporarily cutting off electric power and delaying trains. Lapilli broke car windshields and solar water heaters at 1919 on 11 August, at 0816 on the 14th, and at 1142 on the 16th.

Minami-dake's activity intensified in September, when 49 explosions were recorded. Successive vigorous ash emissions began with an explosion on 4 September at 1127, followed by three more the same day. An ash cloud moved N and slight ashfall was observed at many points in Kyushu and along the E coast of Honshu (figure 14, left). An eruption column on 9 September rose to 4 km above the summit. An explosion on 12 September at 0156 ejected lapilli up to 1 cm in diameter; a car windshield was broken at the SE foot. On 22 September, activity similar to that on the 4th sent ash over the E coast of Kyushu (figure 14, right).

Figure (see Caption) Figure 14. Locations of reported ashfall from explosions of Sakura-jima on 4 September (left) and 22 September 1985 (right). Numbers beside data points on the 5-6 September map are ashfall in g/m2. Courtesy of JMA.

Forty-seven explosions were recorded in October, but there were no damages. Photographs by Space Shuttle astronauts on 3 and 4 October show a V-shaped plume to the SE of Sakura-jima.

Information Contacts: JMA, Tokyo; W. Daley, NASA, Houston.


November 1985 (SEAN 10:11) Citation IconCite this Report

Vigorous explosions continue

Eruptive activity remained vigorous in November, when 34 explosions were recorded. Frequent powerful explosions produced air shocks and scattered incandescent blocks to about 2 km from the summit. No damages were reported. An explosion on 25 November at 1427 was accompanied by a small pyroclastic flow, which only covered part of the summit area.

The frequency of explosions increased further in early December. By the 5th, 19 explosions were recorded, bringing 1985's total to 416, the largest since discrete explosive activity began in 1955 (figure 15). A series of small explosions on 3 December shattered windows of several buildings in northern Kagoshima and disrupted telephone service in some areas. The summit crater of Minami-dake erupted on 5 December at 0220 and 0648, dropping ash on Kagoshima, but there was no damage.

Figure (see Caption) Figure 15. Summary table of monthly and yearly number of explosions at Sakura-jima since the summit eruption began in 1955. Courtesy of JMA.

Information Contacts: JMA, Tokyo; UPI.


December 1985 (SEAN 10:12) Citation IconCite this Report

Eruption plumes on 24th and 31st

Weather satellite images on 24 and 31 December show eruption plumes from Sakura-jima. On the 24th an approximately 200-km plume extended SW, then turned E for about 60 km. The ash cloud was fairly dense and milky gray in color. On the 31st there was a 120-km V-shaped plume ESE of the volcano. The end of the plume was about 40 km wide and very diffuse.

Further Reference. Eto, T., Kamada, M., and Kobayashi, T., 1987, The 1983-1986 Activities of Sakura-jima Volcano in XIX IUGG General Assembly, 1987, Report on Volcanic Activities and Volcanological Studies in Japan for the Period from 1983 to 1986, p. 18-27.

Information Contacts: M. Matson, NOAA/NESDIS; JMA, Tokyo.


January 1986 (SEAN 11:01) Citation IconCite this Report

Explosions cause damage; data on 30 years of activity

"Frequency of explosions at the summit of Minami-dake further increased in December when a total of 75 explosions were recorded with at least one almost every day. A distinguishing characteristic of December volcanic activity was the reciprocal appearance of earthquake swarms and vigorous summit eruptions. Swarms of earthquakes were recorded on 1, 2, 3, 4, 8, 14, 17, 20, 21, 23, 26, 27, and 31 December, in almost every case the days of fewer explosions (except for 2, 3, and 30 December). Even on those 3 days, swarm activity occurred before or after the phase of summit explosive activity. This fact suggests that magma had been repeatedly and effectively transported in the conduit through the month.

"On 3 December at 0103, an explosion was accompanied by an airshock, strong enough to break 188 windowpanes in the city of Kagoshima, ~10 km W of the crater. Another strong shock on 19 December at 0546 broke 85 windowpanes and a car windshield in Ushine city, ~13 km ESE of the crater (table 7). In both cases, the presence of an inversion layer at 1,000 m altitude (3 December) and 1,500 m altitude (19 December) seemed to amplify the airshocks.

Table 7. Major episodes of damage to windows by airshocks, 1976-85. Damage from explosions at Sakura-jima, 1988-90. Car windshields were broken by block or lapilli fall, whereas windowpanes were mainly broken by air shocks. Ashfall damage is not included.

Date Number of Airshocks Location of Damage
17 May 1976 162 Tarumizu City, Furusato (3 km S)
01 Feb 1977 65 Tarumizu City
30 Nov 1977 102 Arimura (3 km SSE), Furusato (3 km S)
03 Dec 1985 188 Kagoshima City (10 km W), base of volcano
19 Dec 1985 85 Tarumizu City

"Lapilli also caused some damage: a windshield on a car was broken at Kurokami (4.5 km E of the crater) on the 5th, and at the volcano's SW foot on the 16th and 19th. An explosion on 19 December at 1810 ejected incandescent rocks and one of them made a 1-m-diameter hole near an inhabited house at Arimura (3 km SSE of the crater).

"In January, the monthly number of explosions declined to 35 and seismic activity also declined. Lapilli from an explosion on 1 January at 1158 broke the windshields of six cars at the SW foot.

"At [KLMO], 474 explosions were recorded in 1985 and cumulative ashfall was 15,908 g/m2, the largest since the summit eruptive activity began in 1955."

Information Contacts: JMA.


February 1986 (SEAN 11:02) Citation IconCite this Report

Plumes detected on NOAA satellite images

Plumes . . . were recorded on images from the NOAA 9 polar orbiting weather satellite in January (table 8). Most plumes extended SE of the volcano.

Table 8. Lengths of plumes from Sakura-jima detected on NOAA 9 weather satellite images, January 1986.

Date Time Plume Length
11 Jan 1986 1416 150-160 km
12 Jan 1986 1409 40-50 km
20 Jan 1986 1424 25-30 km
22 Jan 1986 1401 160 km
27 Jan 1986 1446 180 km
28 Jan 1986 1446 180 km

Information Contacts: Will Gould, NOAA/NESDIS/SDSD.


March 1986 (SEAN 11:03) Citation IconCite this Report

Less frequent explosions; earthquake swarms

Eight explosions . . . were recorded in February and 13 in March. The explosions caused no damage. The maximum ash cloud height was 1,500 m above the crater. Bursts of microearthquakes, typical of Sakura-jima, occurred on 10, 11, 23, and 31 March.

Information Contacts: JMA.


April 1986 (SEAN 11:04) Citation IconCite this Report

Explosions increase in April

In April, 55 explosions . . . were recorded. The highest ash cloud, on 25 April, rose 3,200 m above the crater. An air shock from an explosion on 16 April at 0537 broke windows and glass doors 3 km away at the foot of the volcano. Lapilli from an explosion on 23 April at 1207 broke car windshields near the volcano. Typical bursts of microearthquakes occurred on 5, 11, 15, 25, and 26 April.

Information Contacts: JMA.


May 1986 (SEAN 11:05) Citation IconCite this Report

Fewer explosions

Eight explosions were recorded in May . . ., a marked decline from April. The May explosions did not cause any damage. The month's highest ash cloud rose 1,000 m . . . on 21 May at 1014. Typical bursts of microearthquakes occurred on 3 and 16 May.

Information Contacts: JMA.


June 1986 (SEAN 11:06) Citation IconCite this Report

Airliner lands safely after flying through ash cloud

Twelve explosions . . . were recorded in June, increasing from eight in May. A total of 131 explosions were recorded January-June 1986.

Lapilli from an explosion on 10 June at 1100 broke windshields of three cars near the volcano; another windshield was broken on the 12th at 1024. Ash from the explosion on 12 June fell heavily at Kagoshima City (population 520,000), 10 km W of the volcano. Lapilli or blocks from the explosion on 24 June at 0912 broke windshields on eight cars and damaged roofs of about 30 houses near the volcano.

A TOA Domestic airlines DC9 with 152 passengers and a crew of six flew into the 24 June cloud at 1,200 m altitude, 23 minutes after it was ejected. Cockpit windshields and front surfaces of wings were badly scratched by ejecta. The airliner, enroute from Fukuoka, landed safely at Kagoshima. Damages to planes flying through volcanic clouds have occurred eight times near the volcano in the past (table 9).

Table 9. Damage to aircraft caused by tephra from Sakura-jima, 1970-June 1986. ANA: All Nippon Airways, TDA: Toa Domestic Airlines. Times are for explosions, rather than aircraft damage.

Date Time Damage
08 Apr 1975 1419 ANA airliner (L1011): windshields cracked.
25 Dec 1977 0859 ANA airliner (L1011): windshields cracked.
04 Dec 1978 1155 ANA airliner (L1011): windshields cracked.
18 Nov 1979 0742 Two ANA airliners (L1011) at 0801 and 0805: windshields cracked.
18 Dec 1979 2118 ANA airliner (L1011): windshields cracked.
24 Dec 1979 1740 TDA airliner (YS11): windshields cracked.
23 Nov 1982 1532 Nauru Air passenger plane (B727): windshields cracked.
24 Jun 1986 0912 TDA airliner (DC9): windshields scratched.

Information Contacts: JMA.


July 1986 (SEAN 11:07) Citation IconCite this Report

Explosions; heavy ashfall

There were four recorded explosions . . . in July, on the 1st, 6th, 19th and 20th. Ashfall was heavy during the last part of the month, especially on the 28th and 30th. Some facilities of the National Railroad malfunctioned due to ashfall, causing delays in train operation on the 29th. Monthly ashfall accumulation was 1,533 g/m2, sixth highest since 1969 (when observation of ash accumulation started at KLMO). The maximum plume height over the crater was 3,000 m on 28 July.

Information Contacts: JMA.


August 1986 (SEAN 11:08) Citation IconCite this Report

More explosions; earthquake swarms

. . . there were 22 explosions . . . in August. The maximum plume height was 1,800 m above the summit. Earthquake swarms . . . occurred 2, 5, 11, 23, and 24 August.

Information Contacts: JMA.


September 1986 (SEAN 11:09) Citation IconCite this Report

Explosions and earthquake swarms

Twenty explosions . . . were recorded in September. The maximum plume height was 1,800 m above the crater on 23 September. September ash accumulation at [KLMO] was 171 g/m2, an order of magnitude less than in June and July. Earthquake swarms occurred on 14 days in September.

Information Contacts: JMA.


November 1986 (SEAN 11:11) Citation IconCite this Report

Ash and block eruptions; 2.5 m block injures six people

At 1602 on 23 November, the 206th explosion recorded this year ejected a 2.5-m-diameter block onto a one-story concrete building at the foot of the volcano, 3 km S of the crater. Six people in the building were injured as the block, estimated to weigh 5 metric tons, broke through the roof and ground floor of the hotel and landed in the basement. Two other large blocks (1-1.5 m diameter) that landed near the hotel created a depression and started a grass fire. On 27 November, at 0532, 300-m eruption columns were emitted. Observers heard a loud explosion and saw blocks being ejected. Twelve explosions were recorded in November, and total ash accumulation was 52 g/m2, at [KLMO].

During October, 21 explosions were recorded and earthquake swarms occured on 9 days. The ash cloud reached its maximun height of 2,000 m above the crater on 11, 12, and 30 October. At 1150 on 30 October a large amount of lapilli was ejected, damaging three car windshields. A total of 25 g/m2 of ash accumulated at [KLMO].

Information Contacts: JMA; NHK Television Network, Tokyo; The Daily Yomiuri newspaper, Tokyo; Kyodo News Agency, Tokyo; UPI.


January 1987 (SEAN 12:01) Citation IconCite this Report

Lapilli damages car windshields

Six explosions . . . were recorded during December, bringing the 1986 total to 213. Eruptive activity and seismicity increased toward the end of the month. Explosions on 19 December at 1347 and 30 December at 0916 ejected large amounts of lapilli that broke nearby car windshields. The 30 December ash cloud reached 2,500 m above the crater. Total ashfall for the month was 28 g/m2 at [KLMO]. Earthquake swarms occurred on 5 days.

During January, 13 explosions were recorded. Maximum ash cloud height was 2,800 m above Minami-dake crater, on 8 January. Earthquake swarms were recorded on 2, 4, 13, 18, and 20 January. No ash accumulation was recorded at [KLMO].

Information Contacts: JMA.


April 1987 (SEAN 12:04) Citation IconCite this Report

Fewer summit explosions

No explosions . . . were recorded in February or most of March but on 30 March at 2304 the 14th recorded explosion of 1987 occurred. Ash emissions without recorded explosion events had continued. The maximum ash cloud height was 1,300 m on 20 March. A total of 3 g/m2 of ash accumulated in March at [KLMO]. No ash had accumulated in February.

Information Contacts: JMA; UPI.


May 1987 (SEAN 12:05) Citation IconCite this Report

Minor ash eruptions but no recorded explosions

No explosions were recorded during April although ash clouds were often present. The maximum ash cloud height was 1,500 m above the summit crater (Minami-dake) on 3, 4, and 8 April. 43 g/m2 of ash accumulated at [KLMO]. Only one explosion has been recorded since 24 January. This is the lowest level of activity since May-August 1979.

Information Contacts: JMA.


June 1987 (SEAN 12:06) Citation IconCite this Report

Explosions and ash emission continue; gas damages trees

An explosion was recorded . . . at 1718 on 14 May, for the first time in 1.5 months. Only two explosions had been recorded since 23 January but quiet ash emission occurred about 20 times a month during those four months. The explosion did not cause any damage. Three explosions were recorded in June, on the 14th, 15th, and 19th. Volcanic gas mixed with rain damaged the island's orange orchard and trees in Kagoshima City . . . on 15 and 16 June. Maximum ash cloud height was 1,500 m on 5 and 13 June. 335 g/m2 of ash accumulated in June at [KLMO]. About 100-400 explosions have been recorded yearly since 1955, with 476 explosions in 1985 and 216 in 1986. Only 18 explosions have been recorded this year, 13 in January.

Information Contacts: JMA.


July 1987 (SEAN 12:07) Citation IconCite this Report

Explosions, ash emission continues

Four explosions . . . were recorded in July . . . . Ash emissions without explosion shocks were often observed. The July explosions did not cause any damage. The maximum ash cloud height was 900 m above the crater on 25 July. A total of 81 g/m2 of ash accumulated in July at [KLMO]. Earthquake swarms were recorded on 16, 19, 20, and 25 July.

Information Contacts: JMA.


August 1987 (SEAN 12:08) Citation IconCite this Report

Explosions continue

Three explosions . . . were recorded in August, bringing the 1987 total of explosions to 25. The month's highest ash plume reached 1,700 m and accompanied quiet ash emission on 22 August. Ash accumulated 51 g/m2 during the month at [KLMO]. The eruptions did not cause any damage.

Information Contacts: JMA.


September 1987 (SEAN 12:09) Citation IconCite this Report

Explosions damage windshields, roofs

Eighteen explosions . . . were recorded in September. Monthly ash accumulation at [KLMO] reached 1,093 g/m2, the largest value for September ash accumulation since measurement began in 1969. An explosion at 0612 on 24 September generated a loud sound and strong air shock. Lapilli broke or damaged seven car windshields, a house windowpane, 14 rooftop solar water heaters, and five roof tiles. A large amount of lapilli fell on the road from WNW to NW of the summit. The largest clast was 10-20 cm long. Ash emission following the explosion continued until 1330, resulting in heavy ash accumulation.

Information Contacts: JMA.


October 1987 (SEAN 12:10) Citation IconCite this Report

Explosions continue; ash plumes; felt airshocks

Sixteen explosions were recorded in October. No explosions had been recorded for about a month after a large explosion on 24 September, but the level of activity increased toward the end of October. Ash plumes rose to 3,000 m above the crater of Minami-dake on 29 and 31 October. Ten air shocks were felt and seven explosion sounds were heard during the month. October ash accumulation was 619 g/m2 at [KLMO].

Information Contacts: JMA.


December 1987 (SEAN 12:12) Citation IconCite this Report

Large explosions break windows; blocks burn cars

Sixteen explosions from the summit crater, some causing damage, were recorded in November. The ash plume reached a maximum height of more than 4 km above the summit on 11 November. Monthly ash accumulation 10 km NW of the summit was 879 g/m2.

Three explosions were particularly strong. The first, at 1536 on 14 November, ejected a large amount of ash to 3.2 km height. Lapilli broke car windshields in the S part of the island. An explosion at 2056 on 17 November was the largest of 1987. An incandescent column reached 1 km, the highest since frequent explosions began in 1955. Large numbers of incandescent blocks were ejected for about 2 hours, burning cars parked at the foot of the volcano. More than 70 instances of volcanic lightning were observed in the eruption cloud. Eight car windshields and 23 solar water heaters were cracked by lapilli. A traffic accident, where a truck lost traction and crashed into a house, was attributed to volcanic ash that had fallen on the road. At 1119 on 28 November an explosion broke eight house windowpanes in Tarumizu city, 10 km SE of the summit. A window in a hotel on the S part of the island was cracked by the air shock.

Information Contacts: JMA.


January 1988 (SEAN 13:01) Citation IconCite this Report

More explosions; windows cracked

Although the 1987 total of 106 explosions was significantly below the 216 recorded in 1986, December's 31 explosions represented the highest monthly figure of 1987, and an explosion on 19 December sent an ash plume to 3,500 m above the summit. Monthly ash accumulation at [KLMO] was 3 g/m2. Air shocks were felt at the observatory from 22 of the 31 explosions. No damage was reported.

January had 29 explosions, many of which ejected large amounts of lapilli. An explosion on 30 January at 2206 generated a loud sound, and a strong air shock that cracked 35 windowpanes at hotels and a house on the S part of the island. No explosion had damaged as many windows since 6 February 1986. January's highest ash plume reached 3,000 m above the crater at 1227 on the 3rd. Monthly ash accumulation at KLMO was 5 g/m2.

Information Contacts: JMA.


February 1988 (SEAN 13:02) Citation IconCite this Report

More frequent explosions break windows

Explosive activity has become more vigorous in 1988. Explosions occurred at a rate of 1-2/day in February and often ejected large amounts of lapilli that fell on the flanks. The maximum ash cloud height was 2,500 m above the summit crater. A loud explosion at 1252 on 3 February ejected a large ash cloud, and strong air shocks were felt at [KLMO]. Lapilli broke the windshields of two cars and the air shock broke three windowpanes at a hotel and school. An explosion on 9 February at 1852 ejected a large amount of lapilli, breaking a car windshield. Ash accumulation at the observatory was 48 g/m2. February's 35 recorded explosions brought the year's total to 64.

Information Contacts: JMA.


March 1988 (SEAN 13:03) Citation IconCite this Report

Strong explosions

The number of recorded explosions . . . declined from 35 in February to 21 in March . . . . The explosions often ejected large amounts of lapilli onto the flanks. At [KLMO], March ash accumulation totaled 934 g/m2; 15 explosion sounds were heard and 19 air shocks were felt there during the month.

An explosion on 27 March at 1252, accompanied by a loud sound and strong air shock, ejected an ash cloud that rose more than 4,000 m above the crater. Flank lapilli fall was heavy, breaking windshields of two cars at the E foot of the volcano, and the air shock cracked two windows at a hotel.

Information Contacts: JMA.


April 1988 (SEAN 13:04) Citation IconCite this Report

Explosions and air shocks; ash accumulation declines

April's 19 recorded explosions brought the year's total to 104. No damage was reported. The maximum April ash cloud height was 2,000 m above Minami-dake crater, from the explosion at 0836 on the 20th. The month's ash accumulation was 222 g/m2 [at KLMO]. Air shocks were felt at the observatory from 18 of the 19 explosions.

Information Contacts: JMA.


May 1988 (SEAN 13:05) Citation IconCite this Report

Continued explosions and ash emission

Twelve explosions were recorded in May. Nine . . . were followed by air shocks. The month's highest plume rose 2,700 m after an explosion on 14 May at 0857. A total of 617 g/m2 of ash accumulated during May at [KLMO].

Information Contacts: JMA.


June 1988 (SEAN 13:06) Citation IconCite this Report

Largest one-day ash accumulation since 1969

The number of recorded summit crater explosions declined to six in June, for a 6-month total of 122. A pair of explosions on 16 June deposited the largest amount of ash (2,671 g/m2) since measurements began in 1969 at KLMO . . . . The month's total ash accumulation was 3,541 g/m2. The largest previous ash accumulation at the observatory was 2,476 g/m2 on 29 July 1985. The 16 June plume was the month's highest (2.6 km). Four June explosions produced air shocks.

Information Contacts: JMA.


July 1988 (SEAN 13:07) Citation IconCite this Report

Explosions continue

In July, 11 explosions . . . were recorded . . . . July's highest plume (3,300 m) was erupted at 1519 on the 9th. The monthly ash accumulation at the observatory was 59 g/m2, a sharp decrease from . . . June. The volcano was relatively quiet during the very successful International Conference on Volcanoes, sponsored by the Kagoshima Prefectural Government and held 19-23 July, just 10 km W of Sakura-jima's active vent.

Information Contacts: JMA.


August 1988 (SEAN 13:08) Citation IconCite this Report

Explosions decrease

In August, six explosions (four of which were followed by sounds) were recorded. Explosions on 4 and 5 August emitted the month's highest plumes (1,800 m). Ash ejections without recorded explosions were observed 13 and 29 August. A total of 175 g/m2 of ash accumulated 10 km W of the summit during the month. On the 24th, a swarm of B-type events was recorded by a seismometer 2.3 km NW of the summit.

Information Contacts: JMA.


October 1988 (SEAN 13:10) Citation IconCite this Report

Continued explosions, tephra emission, and seismicity

In September, three explosions . . . were recorded. Two of the September explosions were followed by air shocks. Ash emission without explosion sounds occurred throughout the month. On 9 September at 0713, an explosion preceded emission of the month's highest plume (2,800 m). At the observatory, 523 g/m2 of ash accumulated during 13 days of ashfall in September. A total of 1,833 volcanic earthquakes were detected at the B station and earthquake swarms were recorded on five days (2, 3, 8, 9, and 29 September).

Activity was low during the first half of October but increased later in the month. Eight explosions were recorded, bringing the year's total to 150. Ashfall at [KLMO] dropped to 393 g/m2 in October. On 23 October, an ash plume reached 2,000 m altitude.

Satellite data showed a plume on 30 August that reached an estimated altitude of 3,600 m and extended ~110 km SE. On 27 September at 2329, a plume extended 40-50 km SE of the volcano, and on 13 October at 2137, a 3,000-m plume extended ~40 km ENE.

Information Contacts: JMA; W. Gould, NOAA.


November 1988 (SEAN 13:11) Citation IconCite this Report

Continued explosions but lighter ashfall

Explosive activity . . . continued with five explosions in November . . . . The explosions caused no damage. An explosion on 1 November at 0234 produced a large air shock and an incandescent column that was 500 m high for 10 seconds. Lightning was seen in the eruption cloud. The highest November ash cloud rose 1,000 m above the summit, accompanying an explosion at 1211 on the 10th. The month's ashfall at KLMO was only 12 g/m2.

Information Contacts: JMA; AP; UPI.


January 1989 (SEAN 14:01) Citation IconCite this Report

Explosions and ashfall decrease

A total of 155 explosions were recorded in 1988, compared to 106 in 1987. Yearly ash accumulation at [KLMO] was 6,503 g/m2, an increase from 1987. No explosions were recorded . . . during December, but two occurred in January, at 0944 on the 26th and 1758 on the 28th. The second event, accompanied by a loud explosive sound and strong air shock, ejected an ash plume to 2000 m above the crater. Windshields of eight cars on the S part of the island were broken by lapilli from the explosion. Only 4 g/m2 of ash accumulated at [KLMO] during [December]. A seismometer 2.3 km NW of the volcano registered 28,283 earthquakes in 1988.

Information Contacts: JMA.


February 1989 (SEAN 14:02) Citation IconCite this Report

Monthly ashfall decreases; two explosions

In February, two explosions . . . were recorded, bringing the year's total to four. On 020 February at 0721, an explosion ejected a moderate amount of ash to 1,300 m. Another explosion at 1212 on 23 February produced a strong air shock and ejected blocks. During the month, 33 g/m2 of ash accumulated at the observatory.

Information Contacts: JMA.


March 1989 (SEAN 14:03) Citation IconCite this Report

Ash emission; earthquake swarm

In March, activity remained weak, with a small amount of ash emission on the 1st. Only one explosion . . . was recorded, bringing the year's total to five. The explosion, at 2258 on 11 March, ejected a 1,500-m plume and was accompanied by an air shock and small explosion sound. No damage was reported. Monthly ash accumulation at KLMO was 116 g/m2. An earthquake swarm was recorded 14-15 March by a seismometer 2.3 km NW of the crater.

Information Contacts: JMA.


April 1989 (SEAN 14:04) Citation IconCite this Report

Summit explosions diminish

Activity . . . in April was lower than in previous years. Single explosions were registered on the 1st, 5th, and 13th. The highest cloud rose 1,600 m on 13 April. Monthly ash accumulation at the observatory was 119 g/m2.

Information Contacts: JMA.


June 1989 (SEAN 14:06) Citation IconCite this Report

Ash emission but no recorded explosions

No explosions . . . were recorded in May or June, but plume emission continued. The highest plume in May rose 1800 m on the 19th. Ash accumulation in May was 112 g/m2 at the observatory. No earthquake swarms were recorded by the nearest seismometer, 2.3 km NW of the crater.

Information Contacts: JMA.


August 1989 (SEAN 14:08) Citation IconCite this Report

First recorded explosion since April

An explosion . . . on 31 August at 0401 was the 9th recorded in 1989. The explosion was accompanied by a strong air shock and a loud sound. A large amount of lapilli fell on the central flank, but caused no damage. No explosions had been recorded since 13 April, but plume emission had continued. August ash accumulation, 10 km west of the crater, was 1,198 g/m2.

Information Contacts: JMA.


September 1989 (SEAN 14:09) Citation IconCite this Report

Frequent minor ash emission; two larger explosions

Minami-dake summit crater frequently emitted small amounts of ash in September. The only two recorded explosions occurred at 0606 on the 5th and 1329 on the 17th. The latter ejected a 2,500-m ash plume, the highest of the month. The explosions caused no damage.

Information Contacts: JMA.


October 1989 (SEAN 14:10) Citation IconCite this Report

Explosions increase

Ten explosions were recorded in October, raising the 1989 total to 21. The activity caused no damage. Maximum plume height was 2,200 m above the crater, on 14 October. The month's ash accumulation at KLMO . . . was 111 g/m2.

Information Contacts: JMA.


November 1989 (SEAN 14:11) Citation IconCite this Report

Explosions eject ash

Ten explosions . . . were recorded in November . . . . The highest November plume rose 3 km above the summit crater on the 8th. Monthly ash accumulation at the observatory was 83 g/m2.

Information Contacts: JMA.


December 1989 (SEAN 14:12) Citation IconCite this Report

1989 activity summarized

A total of 13 explosions were recorded in December; the largest, at 1155 on the 13th, ejected ash to 3,000 m above the crater. Monthly ash accumulation at [KLMO] was 13 g/m2. The explosions caused no damage.

A total of 44 explosions from the summit crater of Minami-dake were recorded in 1989, a decrease from 155 recorded in 1988. Yearly ash accumulation at KLMO was 2,352 g/m2. A seismometer (2.3 km NW of the crater) registered 18,296 earthquakes in 1989.

Information Contacts: JMA.


February 1990 (BGVN 15:02) Citation IconCite this Report

Explosions continue; largest ejects ash to 3,000 m

The summit crater of Minami-dake remained active, with 14 recorded explosions in both January and February. The largest, at 1003 on 11 January and 1659 on 24 February, ejected ash to 3,000 m above the crater rim, but did not cause any damage. Monthly ash accumulation [at KLMO] was 80 g/m2 in January and 144 g/m2 in February.

Information Contacts: JMA.


May 1990 (BGVN 15:05) Citation IconCite this Report

Explosions and ash emissions, structural damage

Explosions have been frequent since October 1989 . . . after 1 year of weaker activity. There were five recorded explosions in March, 12 in April, and 19 in May for a total of 64 in 1990. Ash clouds rose 1-3 km during larger explosions. An air shock from one explosion broke 21 windowpanes on the island and in the city of Kagoshima . . . . This was the first damage from explosions since January 1989. Monthly ash accumulations at the observatory were 457 g/m2 in March, 291 g/m2 in April, and 447 g/m2 in May.

Information Contacts: JMA.


June 1990 (BGVN 15:06) Citation IconCite this Report

Continued explosions and ash accumulation

The summit crater . . . remained active with 12 recorded explosions in June . . . . No damage was caused by the June explosions. An explosion at 1528 on 10 June ejected ash to 3,600 m above the crater, the highest cloud of the month. June ash accumulation [at KLMO] was 730 g/m2.

Information Contacts: JMA.


July 1990 (BGVN 15:07) Citation IconCite this Report

Continued explosions; no damage

. . . Sixteen explosions were recorded in July, bringing the 1990 total to 92. No damage was caused by the July explosions. An explosion on 29 July produced a large ash cloud that rose 2,300 m and deposited 460 g/m2 of ash at [KLMO], the second largest daily amount this year. July ash accumulation was 781 g/m2.

Information Contacts: JMA.


August 1990 (BGVN 15:08) Citation IconCite this Report

Continued vigorous explosions

During August, 20 explosions (with a maximum ash cloud height of 3,000 m on the 23rd) were recorded . . . . A monthly total of 2,307 g/m2 of ash was deposited 10 km W of the crater.

On 28 August at 0230, a large explosion ejected many blocks to the middle flank of the volcano. Twenty lightning flashes were seen in the volcanic cloud. Two car windshields were broken by lapilli 4 km from the summit and two blocks, roughly 60 cm across, fell 3 km S of the summit. No eruption-related damage had been reported since 1 May.

Information Contacts: JMA.


September 1990 (BGVN 15:09) Citation IconCite this Report

Several ash emissions but no recorded explosions

No explosions were recorded during September . . . . Quiet ash emissions occurred periodically, with a maximum column height of 1,800 m above the crater (on 11 and 28 September), producing significantly less ash than prior months . . . . An explosion was recorded on 4 October . . . .

Information Contacts: JMA.


October 1990 (BGVN 15:10) Citation IconCite this Report

Explosions decline, but non-explosive ash emission continues

Minami-dake cone exploded once in October, on the 4th, following 37 days of quiescence. No additional explosions had occurred as of 14 November. The October explosion was the 113th of 1990 and caused no damage. The maximum ash plume height, 3,500 m above the crater, occurred during a quiet emission on the 2nd. A monthly total of 130 g/m2 of ash was deposited 10 km W of the crater . . . .

Information Contacts: JMA.


November 1990 (BGVN 15:11) Citation IconCite this Report

Windows broken by tephra from strong explosions

Explosions . . . on 30 November at 0830 and 1504 . . . occurred after 57 days of quiescence. The ash plume from the morning explosion was the highest of the month, rising more than 4,000 m. Strong winds carried substantial quantities of ejecta southward. Lapilli/block fall 3 km S of the crater (at Arimura) broke four house windowpanes and 13 car windshields. Weather clouds obscured the plume from the afternoon explosion, but tephra was again blown southward by strong winds, breaking five more house windowpanes and seven car windshields at Arimura, and two car windshields at Tarumizu City, 8 km SE of the crater. The year's previous damage from Sakura-jima's explosions was on 1 May (windows broken by an air shock) and 28 August (two car windshields broken by lapilli). At total of 107 grams/m2 of ash were deposited [at the KLMO], down slightly from . . . October.

Information Contacts: JMA.


December 1990 (BGVN 15:12) Citation IconCite this Report

Strong explosions; 4,000-m ash cloud

Minami-dake cone exploded four times in December, bringing the year's total of explosions to 119, up from 44 in 1989. An explosion at 0452 on 4 December ejected incandescent material that formed a column 500 m high, the highest since November 1988. Lightning was observed in the ash cloud for 26 minutes following the explosion. Another explosion, at 1019 on 25 December, ejected a 4,000-m-high ash cloud, and blocks that broke a car windshield 5 km E of the summit crater. It was the fifth event to cause damage during 1990 (table 10). The month's other two explosions occurred on 26 and 28 December. Only 4 g/m2 of ash was deposited 10 km W of the crater during December, a substantial decline from previous months.

Figure (see Caption) Figure 16. Monthly number of recorded explosions at Sakura-jima, 1955-1990. Courtesy of JMA.

Table 10. Damage from explosions at Sakura-jima, 1988-1990. Car windshields were broken by block or lapilli-fall, whereas windowpanes were mainly broken by air shocks. Ashfall damage is not included. Courtesy of JMSA.

Date Damage
30 Jan 1988 35 house windowpanes.
03 Feb 1988 Two car windowshields and four windowpanes.
09 Feb 1988 One car windshield.
27 Mar 1988 Two car windshields.
28 Jan 1989 Eight car windshields.
01 May 1990 21 house windowpanes.
28 Aug 1990 Two car windshields.
30 Nov 1990 Thirteen car windshields and four windowpanes.
30 Nov 1990 Nine car windshields and five windowpanes.
25 Dec 1990 One car windshield.

Further References. Eto, T., 1988, An estimation of the amount and dispersal of volcanic ash-falls ejected by summit eruptions at Sakura-jima volcano: Proceedings, Kagoshima International Conference on Volcanoes, p. 448-451.

Kamo, K., 1988, A dialogue with Sakura-jima volcano: Proceedings, Kagoshima International Conference on Volcanoes, p. 3-13.

Sakura-jima Volcanological Observatory, 1988, Volcano monitoring at the Sakura-jima Volcanological Observatory: Proceedings, Kagoshima International Conference on Volcanoes, p. 230-233.

Uhira, K., and Ueda, Y., 1988, Volcano monitoring at Kagoshima Local Meteorological Observatory of the JMA: Proceedings, Kagoshima International Conference on Volcanoes, p. 227-229.

Information Contacts: JMA.


January 1991 (BGVN 16:01) Citation IconCite this Report

Continued explosions but no damage

Minami-dake cone exploded 16 times in January, but caused no damage. The highest ash cloud of the month reached 1,800 m on 29 January. A total of 29 grams/m2 of ash was deposited [at KLMO].

Information Contacts: JMA.


February 1991 (BGVN 16:02) Citation IconCite this Report

Continued explosions but no damage

Minami-dake cone had ten recorded explosions in February, but the activity caused no damage. The month's highest ash cloud reached 1,200 m. A total of 6 grams/m2 of ash was deposited [at KLMO]. Two swarms of volcanic earthquakes were recorded, on 16 and 28 February.

Information Contacts: JMA.


March 1991 (BGVN 16:03) Citation IconCite this Report

Most explosions since 1988; no damage

Minami-dake cone exploded 37 times in March . . ., the highest monthly total since February 1988. No damages were caused by the explosions. The month's highest ash cloud reached 2,700 m. A total of 19 g/m2 of ash was deposited in March [at KLMO]. Swarms of volcanic earthquakes were recorded on 6, 8, 12, and 20 March.

Information Contacts: JMA.


April 1991 (BGVN 16:04) Citation IconCite this Report

Continued vigorous explosions

Explosive activity has remained at high levels since mid-January, totaling . . . 42 [explosions] in April (the highest monthly total since April 1986), and 15 through 16 May . . . . The explosions caused no damage. The highest April ash cloud rose 3,000 m on the 30th. April ashfall was 187 g/m2 [at KLMO]. Earthquake swarms were recorded on four days, a normal monthly total for the volcano.

Information Contacts: JMA.


May 1991 (BGVN 16:05) Citation IconCite this Report

Frequent explosions continue

Frequent explosions continued through mid-June, with 17 recorded in May and 20 as of 19 June, bringing the year's total to 142. The highest ash clouds rose 3,000 m on 3 May and 2300 m on 18 June. An air shock from a 10 May explosion broke a window, the first explosion damage since December 1990.

Information Contacts: JMA.


June 1991 (BGVN 16:06) Citation IconCite this Report

Explosions remain frequent; tephra from one explosion damages houses and cars

Frequent explosive activity . . . continued through mid-July. Explosions . . . occurred 31 times in June . . . and 15 times by 24 July, bringing the year's total to 168. An explosion at 2345 on 29 June ejected blocks and lapilli that damaged house roofs and two car windshields, the second episode of explosion-related damage in 1991. The ash cloud rose to a maximum height of 3,200 m (on 27 June), and a monthly total of 20 g/m2 of ash was deposited 10 km W of the crater (compared to 209 g/m2 in May). Volcanic earthquake swarms, similar to previous months, were recorded on 7, 16, 24, and 28 June.

Information Contacts: JMA.


July 1991 (BGVN 16:07) Citation IconCite this Report

Frequent explosions; aircraft windshield damaged

Eighteen explosions occurred . . . in July . . ., bringing the yearly total to 171. Ejecta from an explosion at 1057 on 5 August struck the windshield of a Boeing 737 airliner 13 minutes later as it flew at an altitude of 1.2 km, 10 km N of the volcano. A crack 50 cm long formed in the outer surface of the windshield, but the plane (domestic flight ANK 793) landed its 122 passengers and five crew safely. Dense weather clouds had prevented the pilot from seeing the eruption plume. This was the first incident of in-flight damage since 24 June 1986, and the 12th near the volcano since 1975. A car windshield a few kilometers from the crater was cracked by ejecta from another explosion (at 1249) the same day. These were the third and fourth cases of explosion-related damage in 1991.

On 23 July, the month's highest ash cloud rose 2,500 m. Prevailing wind directions prevented ash from being deposited at [KLMO]. Earthquake swarms, not unusual for Sakura-jima, were recorded on 1, 2, 9, 15, 18, 21, and 22 July.

Information Contacts: JMA.


August 1991 (BGVN 16:08) Citation IconCite this Report

Explosions continue

Nineteen explosions occurred . . . in August . . . . Ejecta from an explosion on 5 August at 1057 cracked the windshield of an airliner in flight. A car windshield was cracked by tephra from an explosion at 1249 the same day and another was broken on 20 August at 0851, both on Sakura-jima Island, 3 km from the crater. The month's highest ash cloud rose 4,000 m. A total of 583 g/m2 of ash was deposited [at KLMO]; a change in the usual wind direction had carried ash away from this site in July. Typical volcanic earthquake swarms were recorded on 3, 15, 16, and 29 August.

Similar activity continued through mid-September, adding 15 explosions as of the 14th . . . . The highest September ash cloud reached 1,800 m height.

Information Contacts: JMA.


September 1991 (BGVN 16:09) Citation IconCite this Report

Continued explosions but decreased ashfall

Explosive activity continued . . . with September's 21 explosions . . . . The month's highest ash plume rose 2,000 m . . . and a total of 108 g/m2 of ash . . . was deposited [at KLMO]. No swarms of volcanic earthquakes were recorded. Similar activity continued through early October, with 13 explosions occurring by the 13th.

Information Contacts: JMA.


October 1991 (BGVN 16:10) Citation IconCite this Report

Fewer explosions

The 32 recorded explosions . . . in October . . . caused no damage. The month's highest ash cloud rose 4 km above the crater. Ash deposition [at KLMO] was 93 g/m2 . . . . Swarms of volcanic earthquakes were recorded on 2, 4, 10, and 18 October. Explosions became less frequent in November, with only three as of the 17th . . . .

Information Contacts: JMA.


November 1991 (BGVN 16:11) Citation IconCite this Report

Continued explosions

Fifteen explosions were recorded in November . . . . A car windshield was cracked by lapilli from the month's highest ash cloud (3,000 m), emitted at 1245 on 18 November. A total of 332 g/m2 of ash was deposited [at KLMO] in November . . . . Swarms of volcanic earthquakes were recorded on 3, 5, 10, 19, and 28 November.

Information Contacts: JMA.


December 1991 (BGVN 16:12) Citation IconCite this Report

More frequent explosions and stronger seismicity

The number of explosions . . . increased . . . to 37 in December (figure 17), bringing the 1991 total to 295, the highest since 474 explosions were recorded in 1985. The December 1991 activity deposited 266 g/m2 of ash [at KLMO] . . . . An explosion at 1742 on 16 December produced the month's highest ash cloud, which rose more than 3 km above the crater. The air shock from an explosion on 5 December at 1246 broke a glass door; no other damage was reported. Similar eruptive activity continued through mid-January, adding 15 explosions by the 17th. Seismicity was more vigorous than usual during December. Swarms of volcanic earthquakes were recorded on 1, 3, 16, 17, 21-27, and 29 December.

Figure (see Caption) Figure 17. Monthly number of explosions (top) and ash accumulation 10 km W of the crater (bottom) at Sakura-jima, 1980-1991. Courtesy of JMA.

Information Contacts: JMA.


January 1992 (BGVN 17:01) Citation IconCite this Report

Monthly explosion total largest since 1985; increased seismicity

Sixty explosions were recorded at Minami-dake cone in January, . . . marking the highest monthly total since December 1985. The month's highest ash cloud rose > 2,500 m at 0906 on 16 January, and a car windshield was cracked by lapilli during an explosion at 1725 on 2 January. A total of 206 g/m2 of ash was deposited [at KLMO] during the month . . . . Seismicity was higher than usual, with earthquake swarms on 5, 7, 9, 10, 15, 19, 20, and 26 January. Similar activity continued through early February.

Information Contacts: JMA.


February 1992 (BGVN 17:02) Citation IconCite this Report

Fewer explosions, but tephra cracks car windshields; seismicity remains high

The monthly number of recorded explosions declined from a 6-year high of 60 in January, to 16 in February. Seven car wind shields were cracked by lapilli from an explosion at 1009 on 1 February, and two more were cracked at 0630 on 2 February, when the month's highest plume rose 3.5 km. Seismicity was higher than normal, with swarms of volcanic earthquakes recorded on 4, 7-15, 17-19, and 23-29 February.

Information Contacts: JMA.


March 1992 (BGVN 17:03) Citation IconCite this Report

Fewer explosions but stronger seismicity

Ten explosions were recorded . . . in March . . . . The month's highest ash cloud rose 1,900 m on 13 March. Seismicity was more vigorous than usual, with volcanic earthquake swarms recorded almost daily from 14 to 29 March, each lasting 4-5 hours.

Information Contacts: JMA.


April 1992 (BGVN 17:04) Citation IconCite this Report

Explosions; continued strong seismicity

Seismicity remained higher than usual, with 13 swarms recorded in April, each lasting for about 5 hours. Twelve explosions occurred . . . in April, . . . producing ash clouds to 2,500 m (on 2 April).

Information Contacts: JMA.


May 1992 (BGVN 17:05) Citation IconCite this Report

Explosions and seismic swarms continue

Eight explosions occurred . . . in May . . . . The month's highest ash plume rose 2,500 m on 22 May. Seismic swarms were recorded seven times in May, each lasting for ~5 hours, normal for the volcano.

Information Contacts: JMA.


June 1992 (BGVN 17:06) Citation IconCite this Report

Explosions and seismicity less frequent

Only two explosions occurred . . . in June, causing no damage. The month's highest ash clouds rose 2,000 m on 9 and 18 June. Two 9-hour swarms of volcanic earthquakes were recorded, a relatively low level of seismicity for the volcano.

Information Contacts: JMA.


July 1992 (BGVN 17:07) Citation IconCite this Report

Occasional seismically recorded explosions and frequent quiet ash emissions

Six explosions . . . occurred in July, but caused no damage. Although explosions detected by seismic instruments, sounds, and air shocks have been infrequent since May, 31 quiet ash emissions were seen in May, 14 in June, and 19 in July, comparable to previous months. Ground observers reported that July's highest ash cloud rose 3.5 km (to ~4.5 km altitude) on the 29th. Captain Greg Wolfsheimer (Northwest Airlines) reported that a moderately dense, light-gray cloud was rising to more than 5 km altitude when his aircraft passed Sakura-jima at 1735 that day. No volcanic earthquake swarms were recorded in July.

Information Contacts: JMA; G. Wolfsheimer, Gig Harbor, WA.


August 1992 (BGVN 17:08) Citation IconCite this Report

Seismically recorded explosions halt briefly, but quiet ash emission continues

No explosions were recorded in August, the first explosion-free month since September 1990. However, ash eruptions without explosion shocks were seen nine times in August. Ash plumes rose 3.5 km . . . on 15 August and 3.2 km on 21 August. The KLMO . . . counts explosions detected by seismometer, microbarometer, felt air-shocks, and sounds. Quiet ash eruptions are detected visually. No swarms of volcanic earthquakes were reported during August.

Similar activity continued through 15 September, with three recorded explosions and seven quiet eruptions. On 7 September at 0552, the first explosion since 29 July ejected a 3-km ash plume with electrical discharges. Ash rose 3.5 km in a quiet eruption on 4 September.

Information Contacts: JMA.


September 1992 (BGVN 17:09) Citation IconCite this Report

Explosions and quiet ash emissions

An explosion occurred . . . on 7 September, the first since 29 July. Another five explosions were detected and eight quiet ash eruptions were observed in September. The highest ash plume rose 3.5 km . . . on 4 September. No damage has been caused by these eruptions.

Information Contacts: JMA.


October 1992 (BGVN 17:10) Citation IconCite this Report

Increased explosive activity feeds ash plumes and incandescent columns

Eighteen explosions and 18 ash eruptions occurred . . . in October, a significant increase from September. Ten of the 18 seismically recorded explosions produced an incandescent column. The highest column rose 800 m for 60 seconds at 0440 on 20 October, scattering incandescent blocks to 700 m distance. This was the first large incandescent column since glowing material rose 1,000 m on 13 July 1991. The month's highest ash plume rose more than 4 km . . . at 0843 on 22 October. Seismicity was relatively low with no swarms recorded.

Activity continued at a similar rate, with nine explosions and four quiet ash eruptions, through mid-November. The highest ash plume rose 3 km on 11 November. Explosions on 8 and 13 November produced incandescent columns, each lasting 10 seconds and rising 200-300 m.

Information Contacts: JMA.


November 1992 (BGVN 17:11) Citation IconCite this Report

Explosions and ash emission continue

Fifteen seismically recorded explosions and five quiet ash eruptions occurred . . . in November . . . . Three of the 15 explosions produced incandescent columns, rising 300 m. The highest ash plume rose 3 km on 11 October at 1211. . . . Seismicity was relatively low, but one recorded swarm lasted 4.5 hours on 4 November.

Information Contacts: JMA.


December 1992 (BGVN 17:12) Citation IconCite this Report

Continued explosions; no damage

Twelve explosions and three quiet ash eruptions occurred . . . in December . . . . No damage was caused by the eruptions. The highest ash plume rose 2 km on 22 December. Seismicity remained relatively low, with one swarm of 29 earthquakes on 29 December between 0700 and 1900.

A total of 165 explosions was recorded in 1992, down from 295 last year. Yearly ash accumulation [at KLMO] was 2,945 g/m2, up from 1,852 g/m2 in 1991.

Information Contacts: JMA.


January 1993 (BGVN 18:01) Citation IconCite this Report

Continued explosions; no damage

Sixteen explosions occurred . . . in January . . . . No damage was caused by the explosions. The highest ash plume rose 2,900 m on 22 January at 1109. Seismicity remained normal, with two swarms of B-type earthquakes on January 23 (duration 6 hours) and 25 (3 hours).

Information Contacts: JMA.


February 1993 (BGVN 18:02) Citation IconCite this Report

Explosions continue; three earthquake swarms

Explosions . . . continued at a rate similar to that recorded in January. Two of the 15 explosions recorded in February produced observable incandescent columns rising 100 m above the crater. An explosion at 1822 on 3 February produced the highest ash plume of the month, 2,000 m. Seismicity remained normal. Three swarms of B-type earthquakes were recorded: on 9 February (duration 5 hours), 10 February (5 hours), and 25 February (10 hours).

Information Contacts: JMA.


March 1993 (BGVN 18:03) Citation IconCite this Report

40-hour-long earthquake swarm

Explosions continued . . . in March (19 total) . . . . A 40-hour-long swarm of B-type earthquakes occurred on 8-10 March. The highest ash plume of the month, 4,000 m above the crater, resulted from an explosion at 1004 on 5 March.

Information Contacts: JMA.


April 1993 (BGVN 18:04) Citation IconCite this Report

Explosive activity continues; windshield damaged

Seven explosions . . . were recorded in April . . . . Lapilli from an explosion at 1425 on 7 April cracked the windshield of an automobile on the volcano's island. It was the first direct damage from an explosion since February when windshields from nine autos were damaged. An explosion at 0948 on 2 April produced the highest ash plume of the month, >3,200 m above the crater. No earthquake swarms were recorded.

Information Contacts: JMA.


May 1993 (BGVN 18:05) Citation IconCite this Report

Few quiet ash eruptions; no explosions

No explosions occurred . . . in May . . . . The interval 8 April through 14 June (68 days), is the longest explosion-free period since 1989, when 139 consecutive days (between April and August) were without explosions. There were, however, explosion-free ash eruptions during this interval. The first quiet ash eruption was on 24 May, and other single eruptions were recorded on 24, 27, 28, and 30 May, and 12-14 June. The highest ash column of the month rose 2,500 m above the summit on 24 May, and a 3,000-m column was observed 1 June. Seismicity was also at low levels in May and early June.

Information Contacts: JMA.


June 1993 (BGVN 18:06) Citation IconCite this Report

Several quiet ash eruptions; no explosions for 99 days

A total of 13 non-explosive ash eruptions occurred . . . in June . . . . Explosive eruptions accompanying seismic and atmospheric shocks have not occurred between 8 April and 16 July (99 days). This is the longest explosion-free period since 1989, when 139 consecutive days (between April and August) were without explosions. The highest ash cloud of the month, on 1 June, rose 3,000 m above the summit. No earthquake swarms were recorded in June.

Information Contacts: JMA.


August 1993 (BGVN 18:08) Citation IconCite this Report

Longest non-eruptive period since 1972

July was the first eruption-free month since June 1989, although a white (occasionally gray) plume weakly rose 100-200 m above the crater rim throughout the month. Seismicity in July was about 10% of normal, with 331 small earthquakes recorded. . . . Eruptive activity had not resumed as of 13 September, bringing the sequence of explosion-free days to 159 since 8 April. This is the longest explosion-free period in over 20 years. Since the current eruption began in 1955, the longest quiet period prior to this was 307 days from April 1971 until March 1972.

Information Contacts: JMA.


October 1993 (BGVN 18:10) Citation IconCite this Report

Explosions resume after 201 explosion-free days

During September, a white plume weakly rose ~200 m above the crater, similar to the plume observed in July and August. A small amount of ash was contained in the steam plume in late September. Seismicity and volcanic activity remained low through mid-October. Volcanic activity resumed on 20 October when non-explosive eruptions ejected ash 2.1 km above the crater.

An explosive eruption on 26 October ended the sequence of 201 explosion-free days, the second longest quiet period since the current eruption began in 1955. The longest such period lasted for 307 days, from April 1971 until March 1972. Eight more explosions had occurred by 13 November, bringing the total number of explosions in 1993 to 65. The last explosion, on 10 November, ejected ash up to 1.4 km. No damage was caused by any of the eruptions. Earthquake swarms on 5 and 9 November lasted 8 and 13 hours, respectively.

Information Contacts: JMA.


November 1993 (BGVN 18:11) Citation IconCite this Report

Explosive activity continues since late October resumption

. . . after 26 October more explosions took place. In late October there were three explosions, and in November there were 10. Explosions continued at similar levels through early December . . . . No damage was caused by the explosions. The highest ash plume of the month rose 2,300 m above the crater on 27 November. Volcanic earthquake swarms on 5 and 9 November lasted 8 and 13 hours, respectively.

Information Contacts: JMA.


December 1993 (BGVN 18:12) Citation IconCite this Report

Explosive activity increases, but produces no damage

Explosive volcanism continued during December, with 21 explosions recorded, bringing the total number of explosions in 1993 to 91. The highest ash plume of the month rose to 3.5 km on the afternoon of 9 December. Explosive activity has shown a slightly increasing trend since it resumed on 26 October 1993 . . . .

Information Contacts: JMA.


January 1994 (BGVN 19:01) Citation IconCite this Report

Explosive activity decreases from December levels; no damage

Explosive activity decreased with only five explosions in January . . .; no damage was caused. The highest ash plume of the month rose to 3,000 m in the late morning hours of 27 January. There were no volcanic earthquake swarms recorded in January.

Information Contacts: JMA.


February 1994 (BGVN 19:02) Citation IconCite this Report

Explosions continue; one windshield cracked

Explosive volcanism continued in February with 11 distinct eruptions. Ejecta from an explosion on 2 February cracked a car windshield and generated an ash plume that rose 2.5 km, the highest of the month. No volcanic earthquake swarms were registered in February.

Information Contacts: JMA.


April 1994 (BGVN 19:04) Citation IconCite this Report

No earthquake swarms and only one explosion

During the interval 20 February-2 April no eruptions occurred. One minor eruption did take place at 1530 on 3 April, when the volcano sent an ash plume to 1.4 km height. After that Sakura-jima exhibited a low level of activity (no earthquake swarms) through early May. . . .

Information Contacts: JMA.


May 1994 (BGVN 19:05) Citation IconCite this Report

Explosive eruptions resume

Volcanic activity has remained low since the last explosive eruption on 20 February. However, a non-explosive eruption generated an ash plume to 1,400 m altitude on 3 April (19:04). The highest ash plume of the month rose to 1,800 m above sea level at 1506 on 1 May . . . . Two explosions on 30 May caused no damage. Explosive activity has increased since then, with frequent explosions in June.

Information Contacts: JMA.


June 1994 (BGVN 19:06) Citation IconCite this Report

Frequent explosions; ashfall

No damage was caused by any of the 31 eruptions that occurred in June, 19 of which were explosive. Frequent explosions continued through early July. The highest ash plume rose to 2,600 m at 1624 on 7 June. Volcanic earthquake swarms were detected between 1400 and 2200 on 27 June, and during 1600-2200 on the 29th; maximum amplitude was 1.0 µm. [KLMO] measured 31 g/m3 of ashfall during the month.

The following report is from Steve O'Meara. Around 1700 on 29 May the volcano was heavily emitting steam with sand-colored ash. By 1719 part of the steam cloud contained gray ash, giving the appearance of "zebra stripes" in the column. A strong gray cloud was being erupted by 1803 and being blown E by the wind. At 0500 on 30 May, very little steam was evident, however, by 0850 the steam was thicker, and by 1022 an ash eruption was producing gritty ashfall halfway across the bay from Kagoshima city. From the Unohira lookout station W of the volcano, observers noted large ash plumes being released every few seconds. No eruption sounds were detected until 1127 when a low-pitched banging noise could be heard. Ash was accumulating rapidly at the station; by 1135 the ash cloud was filling the intervening valley. Additional observations from the SE and S later that afternoon included steam and steam-and-ash emissions with roaring, rumbling, or jetting sounds. A heavier eruption began in pulses at 1530-1600, with large, sustained ash clouds released about every 5 minutes. A large ash cloud remained at least through 2200, and the eruption was over by 1150 the next day (31 May). Another eruption began at 1630 on 31 May. It sent ash plumes towards Kagoshima and was accompanied by sounds like muted cannon fire.

Information Contacts: JMA; S. O'Meara, Sky & Telescope.


July 1994 (BGVN 19:07) Citation IconCite this Report

Volcanism continues; 14 explosive eruptions

Sakura-jima generated 22 eruptions in July, including 14 explosive ones. None of them caused damage. The highest plume rose to 2.2 km (at 1859 on 5 July). In July, the amount of ashfall at [KLMO] was 237 g/m3. Volcanic swarms were absent in July but 520 earthquakes were detected at a seismic station 2.3 km NW of Minami-dake crater.

Information Contacts: JMA.


August 1994 (BGVN 19:08) Citation IconCite this Report

Number of eruptions and amount of ashfall increase

Volcanic activity increased in August . . . with 55 eruptions . . . including 17 explosive ones. No damage was caused. The highest ash plume of the month rose to 3,200 m at 1725 on 24 August. No volcanic swarms were registered, but 861 earthquakes were detected at a station 2.3 km NW of Minamidake crater. Heavy ashfall was observed on 21 August (159 g/m2) at [KLMO]. Total ashfall . . . during August was 425 g/m2.

Information Contacts: JMA.


September 1994 (BGVN 19:09) Citation IconCite this Report

Eruptive activity decreases

Explosive volcanism continued through September but caused no damage. Nine eruptions occurred . . ., including four explosive ones, a significant decrease from last month. The highest ash plume of September rose to 3,200 m on the morning of 12 September. No volcanic earthquake swarms were detected, but 438 distinct events were registered at a seismic station 2.3 km NW of Minami-dake crater. Ashfall was sometimes observed at [KLMO], where 425 g/m2 was measured in September.

Information Contacts: JMA.


October 1994 (BGVN 19:10) Citation IconCite this Report

Explosive eruptive activity continues but causes no damage

Explosive volcanism continued through October but caused no damage. There were 31 eruptions . . ., including 14 explosive ones. On 5 October a NOTAM . . . described eruptions at 0136 and 0447 that rose to 3.35 km. On the other hand, JMA reported that at 1628 on 6 October the "highest ash plume of October" rose to 3.3 km, so apparently there was relatively vigorous activity on both days. Volcanic earthquake swarms were detected 130 times, reaching a maximum amplitude of 2 µm. During October, a seismic station 2.3 km NW of Minamidake crater registered 862 distinct events. October ashfall collected at the Kagoshima Meteorological Station, 10 km W, measured 136 g/m2.

Information Contacts: JMA; [SAB].


November 1994 (BGVN 19:11) Citation IconCite this Report

Explosive activity continues; summary of aviation hazards and mitigation efforts

Explosive volcanism continued through November 1994; it caused no damage and was lower than last month in both the number of eruptions and the mass of ash fall collected. There were 21 eruptions from Minami-dake crater, including eight explosive ones. The highest ash plume in November rose to 2,700 m (at 1435 on 10 November). Seismic swarms were registered at a seismic station 2.3 km NW of Minamidake cone between 1900 on 30 November and 0700 on 1 December; earthquakes for the month numbered 427. During November, the mass of ash fall collected [at KLMO], was 60 g/m2.

Volcano monitoring at Kagoshima airport. Recent papers discussed the challenge of operating aircraft in vicinity of active volcanoes, including Sakura-jima (Onodera and Kamo, 1994; Casadevall, 1994). In Japan, 19 out of 83 volcanoes are actively steaming and under constant surveillance by JMA headquarters or local observatories; the other volcanoes are regularly patrolled by "Mobile Volcanic Observation Teams" based in four cities. These surveillance groups disseminate critical eruption information to relevant organizations, for example, Aviation Weather Service Centers, Air Traffic Control Centers, and airlines.

The key components of the Sakura-jima monitoring system consist of a seismometer for detecting earthquakes and an infrasonic microphone for detecting air shocks produced by explosive eruptions. An additional prediction system includes other instruments, such as water tube tiltmeters and extensometers. Even though the monitoring system can detect volcanic emissions nearly instantaneously, a time delay of at least a couple of minutes allows volcanological officers to confirm the responses of the monitoring equipment. This time delay also allows for time to edit and dispatch outgoing SIGMET or notification messages. In general, a SIGMET (Significant Meteorological Event) gets issued when the volcanic ash cloud reaches cruising flight elevation or higher.

While in general the several-minute time delay may not cause serious aviation safety problems, it may be crucial when aircraft are close to volcanoes, as at Sakura-jima. In considering problems such as these, the investigators developed a working model to quantify hazards. They expressed the relationship between magnitude of danger (D), eruption magnitude (M), volcano-aircraft distance (L), and a constant that may be affected by wind and related atmospheric conditions (k): D = kM/L.

Aircraft operations adjacent Sakura-jima. Figure 18 shows Kagoshima airport, at the S tip of Kyushu Island, sitting 22 km N of Sakura-jima's active crater. One of Japan's busiest airports, it has about 130 large transport takeoffs and landings a day; aircraft on the lowest category approach (ILS RWY34) pass a point 17 km NE of Sakura-jima's crater. Meanwhile, Sakura-jima produces over 100 explosive eruptions a year on average, but over 400 eruptions on some years (figure 19). Ash production has also been measured for the years 1978-93 (figure 20). It varied by a factor of about 5.5. At Sakura-jima there were 12 encounters between aircraft and volcanic ash during the years 1975-91 (Onodera and Kamo, 1994).

Figure (see Caption) Figure 18. Sakura-jima airport showing both normal and ash avoidance air routes (top). More detailed map of the volcano and airport showing an air route and the JAL observation site (bottom). Courtesy of Onadera, Iguchi, and Ishihara.
Figure (see Caption) Figure 19. Annual number of explosions and mass of ashfall from Sakura-jima (1978-1993, with 1994 annual total up to July also shown). Courtesy of Onadera, Iguchi, and Ishihara.
Figure (see Caption) Figure 20. Annual number of explosions from Sakura-jima (1955 to July 1994). Arrows indicate small pyroclastic-flow episodes. Courtesy of Onadera and others (1994).

References. Onodera, S., Iguchi, M., and Ishihara, K., Recent advances in Japan, Volcano monitoring system of Japan Airlines at Kagoshima Airport: 9th Annual International Oceanic Airspace Conference, 9 November 1994.

Casadevall, T.J., 1994, Volcanic ash and aviation safety: Proceedings of the first International Symposium on Volcanic Ash and Aviation Safety, July 1991, Seattle, Washington, USGS Bulletin 2047, 450 p.

Information Contacts: JMA; S. Onodera, Japan Airlines; K. Kamo, M. Iguchi, and K. Ishihara, Sakurajima Volcano Observatory, Kyoto Univ.


December 1994 (BGVN 19:12) Citation IconCite this Report

Explosive ash eruptions continue

Explosive volcanism . . . continued during December with 64 eruptions, including 54 explosions; no damage occurred. The highest ash plume of the month rose > 2.5 km on 30 December. Volcanic swarms registered at a seismic station 2.3 km NW of Minamidake on 18-19 and 23 December. A total of 743 earthquakes were registered during the month. The ashfall measured at [KLMO] was 16 g/m3.

Volcanism at Sakura-jima in 1994 was generally moderate, with explosive activity during January-February and June-December. Explosions on 2 February broke windshields of two cars. The total number of eruptions in 1994 was 277, including 148 explosive ones.

Information Contacts: JMA.


January 1995 (BGVN 20:01) Citation IconCite this Report

Explosive eruptions cause ashfall but no damage

Activity from Minami-dake crater continued in January with 47 eruptive events, including 41 explosions; no damage was caused. Explosion sounds were heard during nine of these events by personnel at the Kagoshima Meteorological Observatory (10 km W). The highest ash plume of the month rose 2.5 km on 26 January. The next day, a "fire column" rose 300 m above the crater rim. Rockfalls on the 31st traveled midway down the slope of the volcano. A total of 715 volcanic earthquakes registered at the station 2.3 km NW of Minami-dake crater during January. The monthly ashfall amount (10 km W of the crater) was 15 g/m2.

Information Contacts: Volcanological Affairs Office, Seismological and Volcanological Dept, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


March 1995 (BGVN 20:03) Citation IconCite this Report

Explosive eruptions send plumes 3-4 km above the summit

Explosive volcanism continued in February and March from Minami-dake crater but caused no damage. There were a total of 22 eruptions in February, including 12 explosive ones. Activity increased somewhat in March with 36 eruptions, 24 of which were explosive. The highest monthly ash plumes occurred on 11 February (3 km) and on 8 March (4 km). Ashfall measured 10 km W at the Kagoshima Meteorological Observatory (KMO) was 30 g/m2 in February. Although there were more eruptions, only 9 g/m2 of ash fell at KMO during March.

An earthquake swarm that started at 1600 on 23 February lasted 9 hours and consisted of 99 events registered at Station B, 2.3 km NE of Minami-dake crater. This episode caused the KMO to issue a Volcanic Advisory noting the restlessness of the volcano. Station B also registered 208.8 hours of volcanic tremor and a total of 424 volcanic earthquakes during February. Another earthquake swarm between 0000 on 26 March and 0300 on 28 March produced 2,041 earthquakes and 828 tremors, causing another two Volcanic Advisories. However, total amount of tremor in March (164.3 hours) was less than in February.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


May 1995 (BGVN 20:05) Citation IconCite this Report

Explosive ash eruptions continue

During April and May, explosive volcanism continued from Minami-dake crater. Throughout April there were 16 eruptions, 13 of them explosive, with the highest ash plume rising 1,800 m above the summit crater on 7 April (table 11). In May there were 36 eruptions, 17 of which were explosive. The highest ash plume of May rose 2,500 m on the 23rd. Monthly ashfall amounts, collected at Kagoshima Meteorological Observatory, 10 km W of Minami-dake crater, were 14 g/m2 and 20 g/m2, respectively for April and May.

Table 11. Volcanic activity at Sakura-jima, January-May 1995, Courtesy of JMA.

Month Total Eruptions Explosive Eruptions Ash Plume Height Average daily ashfall (g/m2) Tremor EQ's
Jan 1995 47 41 2,500+ m 15 -- 715
Feb 1995 22 12 3,000 m 30 -- 424
Mar 1995 36 24 4,000 m 9 828 2,041
Apr 1995 16 13 1,800 m 14 427 887
May 1995 36 17 2,500 m 20 815 1,008

At a seismic station 2.3 km NE of Minami-dake crater (Station B), 887 earthquakes were recorded in April, and 1,008 in May. Between 1100 and 2200 on 1 April, 147 volcanic earthquakes were registered. There were 427 tremors with a total duration of 138 hours during April, and 815 tremors in May lasted a total of 72 hours.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


July 1995 (BGVN 20:07) Citation IconCite this Report

Only one explosive eruption during July

Volcanism at Sakura-jima continued at a moderate rate through June, and dwindled in July. Throughout June there were 18 eruptions, 10 which were explosive. The highest ash plume of June reached 2,500 m elevation (2 June). The monthly ashfall accumulation at Kagoshima Meteorological Observatory, 10 km W of Minami-dake crater, was 11 g/m2. Throughout June, 550 earthquakes and 349 tremors were recorded at Station B, 2.3 km NE of Minami-dake crater.

During July, Sakura-jima generated only one explosive eruption. The 18 July ash plume rose 2,100 m above the crater rim. The monthly ash fall accumulated at Kagoshima Observatory measured 5g/m2. An earthquake swarm consisting of ~170 events occurred during 1600-2100 on 31 July. The totals for the numbers of monthly earthquakes and tremors at Station B were 655 and 533, respectively.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


August 1995 (BGVN 20:08) Citation IconCite this Report

Explosive activity 23-25 August, dense ash cloud closes a highway

During 1995, the geophysical system described below registered Sakura-jima's 126th explosion on 23 August. During 23-25 August, 28 explosions were recorded. The total through August of 153 explosions is relatively small compared to 1960, 1974, 1983, and 1985, years when over 400 explosions took place. During August no measurable ash fell at Kagoshima Local Meteorological Observatory, 10 km W of the crater. On the other hand, ash-bearing explosions were of sufficient size to send a dense ash cloud NW of the volcano that dropped ash in N Kyushu and closed a highway for an unspecified duration. The highest plume of the month vented on 30 August and rose to 3 km above the crater rim. Station B (2.3 km NE of Minami-dake crater) registered 671 earthquakes and 378 tremor events.

Geophysical determination of explosions. The monthly tally of "explosions" (sometimes also called "explosive eruptions") at Sakura-jima has a geophysical definition, with its origins closely linked to aircraft safety. The volcano sits ~25 km from the busy Kagoshima International Airport and generates frequent Vulcanian explosive eruptions (BGVN 19:11). A video camera monitors the volcano and a real-time image is transmitted to air traffic control. In order to alert aviation dispatchers and pilots of potential hazards regardless of the time of day or the weather, scientists devised a system to rapidly classify the volcano's seismic and acoustic signals (Onodera and Kamo, 1994). This geophysical system has been linked to the Japan Airlines office at Kagoshima Airport since March 1991.

When the amplitudes of incoming seismic signals rise above an established threshold (table 12) their dominant frequency is computed. The above-threshold signals also have an associated air-shock wave that is received at an "infrasonic" microphone with a 0.02-100 Hz detection range. For reference, the low-frequency range of the human ear stops at around 16 Hz. Once the infrasonic air-shock wave is received, the system measures its amplitude and computes its spectrum. The combination of seismic and air-shock amplitudes and spectra allow the events to be classified into "non-eruption," "eruption," or "explosion." categories (table 2).

Table 12. (above) Definition of "explosion" at Sakura-jima, a geophysical characterization of explosive, bomb- and ash-bearing eruptions. (below) Recognized volcanic earthquakes at Sakura-jima, showing the maximum values registered for explosion earthquakes and corresponding air-shock waves (after Onodera and Kamo, 1994).

Criteria for Definition of Explosion at Sakura-jima (~90% accurate when compared to visual observations)
1. Maximum amplitude of explosion earthquake >= 10 microns (0.1 x 10-3 cm/sec).
2. Amplitude of infrasonic air shock >= 0.1 mbars at a site 2.7 km NW of summit crater.
3. Spectral analysis of received infrasonic air-shock discriminates between the categories "non-eruption" (> 5 Hz), "eruption" (2- 5 Hz), and "explosion" (<2 Hz).
Volcanic earthquake type Dominant frequency range Comment
A-type >8 Hz Similar to tectonic earthquakes; devoid of infrasonic air-shocks and not accompanied by eruptive activity.
B-type <5 Hz Includes both BL (1-3 Hz, max. amplitudes <7 x 10-3 cm/sec, reduced displacement <60 cm2 and <1 mb) and BH (5-8 Hz); the former often affiliated with bomb- and ash-bearing eruptions; the latter not affiliated with eruptive activity.
C-type -- Harmonic wave trains, "volcanic tremor"
D'-type -- Non-harmonic tremor; max. amplitudes <7 x 10-3 cm/sec, reduced displacement <60 cm2 and <1 mb; often affiliated with bomb- and ash-bearing eruptions.
Explosion -- Accompanied by strong air-shock waves, and bomb- and ash-bearing. Maximum amplitudes range from 3 x 10-3 to 3 x 10-2 cm/s for the earthquakes (reduced displacements of 50-500 cm2) and 0.1 to 5 mb for the infrasonic air-shock waves.

Although passing typhoons can trigger inappropriate warnings or false alarms, and small-magnitude eruptions may be missed, the number of explosions correlates well with the measured deposition of fresh volcanic ash. The system has been effective at reducing aviation risks. A future goal is to use "explosion" category to automatically trigger the calculation of volcanic ash diffusion based on meteorological data. This program would thus automatically estimate the likely trajectory of ash discharged from the volcano.

References. Onodera, S., Iguchi, M., and Ishihara, K., 1994, Recent advances in Japan, volcano monitoring system of Japan Airlines at Kagoshima Airport: 9th Annual International Oceanic Airspace Conference, 9 November 1994.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan; Saburo Onodera, Director of Meteorology, Flight Operations, Japan Airlines, 3-3-2 Haneda Airport, Tokyo 144, Japan; Kosuke Kamo, Masato Iguchi, and Kazuhiro Ishihara, Sakurajima Volcano Observatory (SVO), Disaster Prevention Research Institute, Kyoto University, Sakurajima-cho, Kagoshima 89114, Japan.


September 1995 (BGVN 20:09) Citation IconCite this Report

Explosions continue, but at much lower levels compared to August

Activity at Minami-dake Crater in September consisted of 13 eruptions, including seven explosive ones. The highest ash plume of the month rose 1,500 m on 15 September. Ashfall measured at the Kagoshima Local Meteorological Observatory, 10 km W, was 26 g/m2. At a seismic station 2.3 km NE of Minami-dake crater (Station B), 449 earthquakes and 431 tremors were recorded.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


October 1995 (BGVN 20:10) Citation IconCite this Report

Explosive activity continues

Activity at Minami-dake crater became high during both early and late October. On 28 October, 9 explosive eruptions occurred and significant volcanic ash fell in Kagoshima City. During October, seismic station B (2.3 km NE of Minami-dake crater) recorded 720 earthquakes and 1,206 tremors. On 27-28 October there were seismic swarms. During October the volcano produced 31 eruptions, 23 of them explosive; the highest ash plume, on 28 October, rose 3 km above the summit crater. October ashfall (measured 10 km W at the Kagoshima Meteorological Observatory) was 117 g/m2.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


December 1995 (BGVN 20:11) Citation IconCite this Report

Explosive eruptions continue to generate ash plumes

Minami-dake crater was active throughout November-December 1995. Eruption totals for November and December were 19 and 42, respectively. Of these, explosive eruptions for the same months numbered 14 and 36, respectively. The local seismic station recorded 453 earthquakes and 446 tremors during November and 467 earthquakes and 83 tremors during December. The highest monthly ash plumes took place on 30 November (2,300 m above the crater), and on 9 December (1,700 m). Ashfall measured 10 km W of the crater was as follows: November, 5 g/m2; and December, 18 g/m2.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


January 1996 (BGVN 21:01) Citation IconCite this Report

Explosive eruptions and ashfalls continue

Minami-dake crater was slightly active throughout January. The monthly total number of eruptions was 60, including 42 explosive ones. At the seismic station 2.3 km NW of Minami-dake crater (Station B), 601 earthquakes and 684 tremors were recorded. The highest ash plume of the month rose 2,300 m above the summit crater on the 21st. Ashfall measured at the Kagoshima Local Meteorological Observatory, 10 km W form the crater, was 41 g/m2.

The VRC noted that there were more than 200 eruptions in 1995; total amount of erupted material was estimated at 3-4 million tons by the Sakurajima Volcanological Observatory, Kyoto University. The latter has been observing continuous uplift on the N side of the volcano, implying accumulation of magma beneath the volcano.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan; Volcano Research Center, Earthquake Research Institute, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html).


February 1996 (BGVN 21:02) Citation IconCite this Report

Explosive ash eruptions continue

During February Minami-dake Crater produced 35 eruptions, including 31 that were explosive. At the seismic station 2.3 km NW of Minami-dake Crater (Station B), 689 earthquakes and 879 tremors were recorded. On 11 February, the highest ash plume during the month rose 1,800 m above the summit crater. Ashfall measured at the Kagoshima Local Meteorological Observatory (KMO), 10 km W of the crater, was 10 g/m2.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


March 1996 (BGVN 21:03) Citation IconCite this Report

Frequent explosive ash eruptions continue

Minor activity continued at Minami-dake until mid-March, although the highest ash plume of the month rose 2,100 m above the crater on the 6th. Twelve explosive eruptions occurred on 18 March. Overall during March there were 88 eruptions, 69 of which were explosive. The monthly total ashfall measured 10 km W of the crater was 22 g/m2. Seismicity recorded 2.3 km NW of the crater during March consisted of 970 earthquakes and 773 tremors.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.


May 1996 (BGVN 21:05) Citation IconCite this Report

Explosive activity continues, decreased activity in May

During April, Miniami-dake crater produced 14 eruptions, including five that were explosive. Seismic station B, 2.3 km NW of Miniami-dake crater, recorded 364 earthquakes and 120 tremors. On 28 April an ash plume rose 3,500 m above the summit crater. This was the highest ash plume observed during the month. A monthly ashfall total of 8 g/m2 of ashfall was measured at the Kagoshima Local Meteorological Observatory (KMO), 10 km W from the crater.

During May, Minami-dake crater produced one explosive eruption. Station B recorded 64 earthquakes and three tremors. The highest ash plume of May rose 3,500 m above the summit crater. The ashfall total at KMO was 6 g/m2.

Information Contacts: Japan Meteorological Agency (JMA), Volcanological Division, Seismological and Volcanological Department, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


June 1996 (BGVN 21:06) Citation IconCite this Report

Explosive activity continues, but at decreased levels in June

An eruption on 16 May sent an ash plume 3,500 m above the summit, to ~4,600 m altitude (BGVN 21:05). This higher than usual ash plume was estimated at 4,880 m altitude in aviation notices from Tokyo. However, the eruption was not detected on GMS satellite imagery. Ths Volcano Research Center also noted that this explosion threw large cinders to 2 km NW of the crater.

According to the Sakura-jima Volcanological Observatory (SVO), Kyoto University, since March there has been a decrease in the amount of air-fall tephra, the frequency of explosions, and earthquakes (including BL, surface, and shallow types).

The Japanese Meterological Agency reported that Minami-dake crater produced four explosive eruptions during June. The highest ash plume of the month rose 900 m above the crater on 22 June. Ashfall measured at the Kagoshima Local Meteorological Station, 10 km from the crater, was 1 g/m2. The seismic station 2.3 km NW of the crater recorded 118 earthquakes and 63 tremors through 29 June. High seismicity began around 0800 on 30 June; 349 earthquakes were recorded that day, bringing the monthly total to 467.

Information Contacts: Volcano Research Center, Earthquake Research Institute, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html); NOAA/NESDIS Synoptic Analysis Branch (SAB), Room 401, 5200 Auth Road, Camp Springs, MD 20746, USA; Volcanological Division, Japan Meteorological Agency, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


July 1996 (BGVN 21:07) Citation IconCite this Report

Minor activity continues

Minami-dake crater had one non-explosive eruption in July. The seismic station 2.3 km NW of the crater (Station B) recorded 136 earthquakes and 29 tremors during July. No ashfall was found at the Kagoshima Local Meteorological Observatory, 10 km W of the crater.

Information Contacts: Volcanological Division, Japan Meteorological Agency, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan


October 1996 (BGVN 21:10) Citation IconCite this Report

Seven explosive eruptions in September and October from Minami-dake

During September, five explosive eruptions occurred in Minami-dake crater, producing 3 g/m2 of ashfall measured at the Kagoshima Local Meteorological Observatory (KMO), 10 km W of the crater. Totals of 145 earthquakes and 43 tremors were recorded during September at Station B, 2.3 km NW of Minami-dake crater. In contrast, eruptive and seismic activity decreased in October. During October, there were two explosive eruptions in Minami-dake crater with <1 g/m2 ashfall at KMO; 19 earthquakes and one tremor were registered at Station B. The highest plume in October rose 1,300 m above the summit crater.

Information Contacts: Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


January 1997 (BGVN 22:01) Citation IconCite this Report

Four explosive eruptions from Minami-dake in December and January

During December and January, Minami-dake crater had six eruptions (four explosive). At a seismic station 2.3 km NW of Minami-dake crater, 342 earthquakes and 14 tremors were recorded in December, and 257 earthquakes and 18 tremors were recorded in January. The highest plume in December rose to a height of 2,700 m. The monthly ashfall measured at the Kagoshima Local Meteorological Observatory (KMO), 10 km W from the crater, was 14 g/m2.

On 14 December, bombs and lapilli were ejected and deposited on the flanks. A small quantity of ashfall was observed at Aburatsu and Miyako-no-jo. During the eruption, 14 lightning strikes occurred during a 10-second interval. January's only eruption produced <1 g/m2 of ashfall at KMO.

Information Contacts: Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


September 1997 (BGVN 22:09) Citation IconCite this Report

Relatively quiet but an 11 May explosion sent bombs hundreds of meters down the flanks

During February-May 1997, the volcano was relatively quiet with occasional small explosions and B-type earthquakes; during March and April, seismic activity was moderate. On 11 May, an explosion of much smaller magnitude than the 14 December 1996 event (BGVN 22:01) created a detectable air-shock and projected bombs 40% of the way down the volcano's slope. The Sakurajima Volcanological Observatory reported increasing A-type earthquakes for a few months before the explosion.

Information Contacts: Sakurajima Volcanological Observatory (SVO), Kyoto University; Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


January 1998 (BGVN 23:01) Citation IconCite this Report

Increased number of explosions during December-January

A 4 February report stated that Sakura-jima was relatively quiet throughout most of 1997. According to the Japan Meteorological Agency (JMA), 4,466 tremors occurred in 1997, the lowest annual total since 1965. The total number of 1997 explosions was 35; the record low was set in 1971 when only 10 explosions occurred.

Activity increased during December 1997-January 1998. During December, eight explosions were observed; during 1-27 January there were ten. According to the Sakurajima Volcanological Observatory (SVO), type-A and type-B earthquake counts were relatively high both months.

A 3 December 1997 explosion issued at least 70,000 tons of ash, the estimated mass of fallout on Sakura-jima island. According to a volcanic ash advisory issued to aviators by the Tokyo Volcanic Ash Advisory Center, the eruption occurred at 1055 and sent ash up to ~3 km. The ash cloud extended 25 km S and 50 km E.

A 24 January 1998 ash advisory reported an eruption at 1750 and ash drifting SE at a height of ~1 km. A ground-based observer reported an ash plume that extended 10 km SE at 2000. Due to cloud cover in the area, ash was not seen on satellite images.

Information Contacts: Sakurajima Volcanological Observatory (SVO), Disaster Prevention Research Institute (DPRI), Kyoto University, Sakurajima, Kagoshima, 891-14, Japan; Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


February 1998 (BGVN 23:02) Citation IconCite this Report

Several explosions during January-February

Sakura-jima produced frequent explosions in December 1997-January 1998 (BGVN 23:01). A 20 January volcanic ash advisory reported an eruption at 1227. An 8 February advisory reported an eruption at 0420; the volcanic ash cloud reached ~2.1 km altitude and drifted SE. A notice later in the day reported another eruption at 0508 with an ash cloud at ~2.1 km altitude extending SE. A 16 February advisory reported an eruption on 15 February that sent a plume to the E at ~18 km altitude. Observers in Kagoshima Airport saw a volcanic ash cloud to the SE and S at 0600 on 16 February. Satellite images did not show a plume due to the presence of low weather clouds. A 24 February ash advisory noted an eruption at 0705; volcanic ash extended E at ~18 km altitude.

Information Contacts: Sakurajima Volcanological Observatory (SVO), Disaster Prevention Research Institute (DPRI), Kyoto University, Sakurajima, Kagoshima, 891-14, Japan; Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


April 1998 (BGVN 23:04) Citation IconCite this Report

Amid ongoing explosions, a 19 May seismic swarm yields 220 earthquakes in 4 hours

In accord with ongoing eruptions, careful monitoring, and close communication with aviators, frequent notices of activity at Sakura-jima were released during March-May. According to various advisories, an eruption at 0130 on 2 March sent ash to ~1.8 km where it drifted 20 km S; an eruption at 0816 on 24 March sent ash to ~1.8 km where it drifted SE; and an eruption at 0505 on 5 April sent ash to ~2.0 km where it drifted N. An advisory noted an eruption at 0253 on 13 April but no ash cloud information was reported.

A Japan Meteorological Agency (JMA) volcanic advisory on 19 May stated that a swarm of volcanic earthquakes started at about 1700; in the following 4 hours, approximately 220 earthquakes were recorded. Daily earthquake counts were 334 on 19 May and 41 on 20 May. During 20-21 May, the volcano produced ten eruptions, nine of which were explosive. JMA scientists warned that the volcano's activity might increase following the swarm. As of 21 May, 49 explosions had occurred at Sakura-jima in 1998.

Information Contacts: Volcano Research Center, Earthquake Research Institute (ERI), University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan; Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan.


May 1999 (BGVN 24:05) Citation IconCite this Report

1998-99 summary report; recent tephra deposits comprise about 3 x 105 tons/month

The following summarizes activity at Sakura-jima during January-June 1998 and January-May 1999. Information concerning events in 1998 were provided through communications from Yosihiro Sawada forwarded by Dan Shackelford. More recent information is available at the Japanese Meteorological Agency website.

The amount of tephra deposited around the volcano peaked during 1991-92 (up to 5.8 x 106 tons/month) but has since decreased; present deposits are <3 x 105 tons/month.

Activity during January-June 1998. Ten explosions and eruptions were recorded in January 1998. One explosion, on 7 January, produced a plume that rose 1,200 m above the summit. An explosive outburst on 24 January produced a column of incandescent ejecta accompanied by volcanic lightning. The total ashfall measured at Kagoshima Local Meteorological Observatory (KLMO) during January amounted to 10 g/m2.

Silent ash emissions (eruptions without explosions) occurred on 8, 16, 25, and 27 February 1998. A plume on 16 February rose 1,400 m above the crater. In March 1998, 22 eruptions (without explosions) were recorded. Eruption plumes on 2 and 3 March rose 1,200 m. KLMO recorded 37 g/m2 of ash for March. In April 1998, there were 19 eruptions, including eight explosions. The highest plume during April was observed 1,500 m above the crater on 30 April. April ashfall totaled only 1 g/m2.

Forty-one eruptions were observed in May 1998, including 27 explosive eruptions. The highest plume observed rose 2,500 m above crater on 24 May. A volcanic earthquake swarm lasted seven hours on 19-20 May. The total May ashfall was 105 g/m2. All five eruptions recorded during June were explosive. On 6 June an eruption plume rose 1,100 m above the crater. The total June ashfall deposit was 5 g/m2 thick.

Activity during January-May 1999. January 1999 was characterized by a low level of volcanic earthquakes, although 13 eruptions occurred. During February-April 1999 observers recorded 44 eruptions, including 15 explosions. Eruptive activity was relatively high during 11-16 March when there were 10 eruptions, including eight explosions. An eruption column rose 1,800 m on 20 April.

Information Contacts: Yosihiro Sawada, Volcanological Division, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL: http://www.jma.go.jp/); Volcano Research Center, Earthquake Research Institute (ERI), University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html); Dan Shackelford, 3124 E. Yorba Linda Blvd., Apt. H-33, Fullerton, CA 92831-2324 USA.


August 1999 (BGVN 24:08) Citation IconCite this Report

Larger than normal eruptions in late July and early August

Sakura-jima volcano had a heightened level of eruptive activity during the period 28 July-12 August. Large eruptions occurred at 2022 on 30 July, at 2216 on 1 August, and at 0030 on 2 August when ballistic ejecta fell as far away as the mid-flank of the volcano. The activity level reduced after 13 August; only one-fifth of the number of explosions occurred during following 10 days. As of 23 August, 78 explosions had occurred during 1999.

Information Contacts: Setsuya Nakada, Volcano Research Center, ERI, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html).


February 2000 (BGVN 25:02) Citation IconCite this Report

Frequent explosive eruptions continue from Minami-dake

The southern-most cone at Sakura-jima, Minami-dake, manifested increased eruptivity from late October to early November 1999. Following a lull in the second half of November, vigorous activity in December was marked by incandescent columns, large amounts of bomb ejections, and ballistics falling as far as 4 km from the crater.

High eruptive activity occurred in late October and early November 1999. On 31 October the JMA issued a Volcanic Advisory. In early November, 19 eruptions (including 18 explosions) occurred at Minami-dake before activity declined to lower levels later in the month. Activity increased again in early December with a few explosions each day and small numbers of ballistic clasts falling onto the upper slopes. On the afternoon of 10 December JMA issued another Volcanic Advisory. At 0555 this day, Sakura-jima issued a large amount of bombs. Incandescent columns as high as 100 m were accompanied 116 times by volcanic lightning. According to a JMA field inspection, ballistics were scattered 3-4 km away from the Minami-dake crater; the maximum size was 4 cm across. Incandescent columns rose as high as 300 m at 0554 on 24 December and were accompanied by volcanic lightning six times.

Daily numbers of eruptions ranged from 2 to 8 during early- to mid-December; eruptions were mostly explosive. The maximum amplitude of explosion earthquakes recorded at JMA observation point A, 4.6-km WNW of the crater, reached up to 28 µm; the largest value was caused by an explosion at 1301 on 12 December. The plume heights of December explosions ranged from 1,500 m to 2,000 m. Explosions took place on 23 consecutive days between 3 and 25 December. This is the longest record of daily explosions since JMA started observing Sakura-jima in 1955; the previous record was 21 days in 1960. Explosions began again late in the month, with six more on 31 December.

The total of 88 explosions during December 1999 was the second highest monthly count since 1955; the highest was 93 explosions in June 1974. According to the JMA, the total number of eruptions in 1999 was 386, including 237 explosions.

Frequent explosive eruptions continued in early January (figure 21). Explosions on 2 January sent an eruption column to 2,200 m above the crater rim and emitted abundant cinders, as well as bombs that fell midway down the flanks of the volcano. Nine explosive eruptions occurred on 5 January, one of which again ejected cinders and bombs as far as the middle flank of the volcano. The highest plumes in early January reached 2,200 m above the crater rim during explosions at 0821 on 5 January and at 0746 on 14 January. The maximum amplitude of explosion seismic signals at JMA observation point A (4.6 km WNW of the active crater) was 17 µm for the 0513 explosion on 14 January.

Figure (see Caption) Figure 21. Eruption at Sakura-jima at 0900 on 8 January 2000 from 3.5 km SW of the Minami-dake crater. Courtesy of Tatsuro Chiba.

Information Contacts: JMA-Fukuoka, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan; Setsuya Nakada, Volcano Research Center, ERI, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html); Tatsuro Chiba, Nihon University, Japan (URL: http://www.nihon-u.ac.jp/en/).


October 2000 (BGVN 25:10) Citation IconCite this Report

Explosion, lapilli and ash fall; pilot encounters ash cloud on 7 October

According to observation reports by the Japan Meteorological Agency (JMA), Minami-dake, the southernmost crater of Sakura-jima, erupted at 1642 on 7 October, marking the 132nd explosion this year. The eruption column reached 5 km above the crater, and was accompanied by volcanic lightning 18 times. The maximum amplitude of the earthquake associated with the explosion was 4 µm at the JMA observation point 4.6 km WNW of Minami-dake. Abundant ash fell over the central and northern sections of Kagoshima. Lapilli with a maximum size of 3 cm fell on the NW portion of the island, breaking 35 car windshields.

A pilot en route from Guam to Fukuoka received a dispatch warning of a major ash cloud in the flight path. The pilot saw the cloud clearly at a distance of 80 km from Sakura-jima and noted a small white plume over the summit. The pilot also observed a brown-red cloud downwind and SE of the volcano at an altitude of 2.5 km. As the aircraft approached, the plume grew suddenly larger and became dark gray during an eruption of ~30-45 seconds duration. The pilot deviated 19 km to the W while descending and flew past the cloud at an altitude of 5.5 km. After passing safely, the pilot observed the ash cloud diffusing ~100 km downwind at an altitude level with the summit. This incident highlights the importance of efficient information relay from field observers through a dispatch to pilots in order to avoid potentially hazardous in-flight ash encounters. As of 17 October no distinct changes in activity at Sakura-jima have been observed, although a small number of volcanic earthquakes have occurred.

Reference. Casadevall, T.J., 1994, Volcanic ash and aviation safety: Proceedings of the First International Symposium on Volcanic Ash and Aviation Safety: U.S. Geological Survey Bulletin 2047.

Information Contacts: JMA-Fukuoka, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan; Setsuya Nakada, Volcano Research Center, ERI, University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113, Japan (URL: http://www.eri.u-tokyo.ac.jp/VRC/index_E.html).


April 2003 (BGVN 28:04) Citation IconCite this Report

Ash plume observed in July 2002; plume photo from 17 April 2003

An observer at Kagoshima Airport reported seeing an ash cloud from Sakura-jima at 0900 on 22 July 2002 that rose to 2.1-2.4 km altitude. An ash plume was visible on satellite imagery at 1052 (0152 UTC) that day extending to the SW.

A photograph taken by the webcam at ttp://yumemaru.com/s/ shows a plume of undetermined composition originating from the island on 17 April 2003 (figure 22). This type of event is common at Sakura-jima.

Figure (see Caption) Figure 22. Photograph of Sakura-jima taken on 17 April 2003 showing a plume originating from the island. Courtesy of Yunemaru.

Information Contacts: Charles Holliday, U.S. Air Force Weather Agency, 106 Peacekeeper Drive, Ste 2NE, Offut AFB, NE 68113-4039, USA (URL: http://www.557weatherwing.af.mil/); Yunemaru (URL: http://yumemaru.com/).


May 2004 (BGVN 29:05) Citation IconCite this Report

Frequent eruptions and ash plumes; 15 May plume noted by news media

Based on information from the Japanese Meteorological Agency (JMA), the Tokyo Volcanic Ash Advisory Center (VAAC) reported that on 3 December 2003 at 2025 ash was emitted from Sakura-jima, rose to ~2.5 km a.s.l., and extended to the S. An eruption on 12 January 2004 at ~1430 produced an ash cloud that rose higher than 2 km altitude. On 19 and 20 February, explosions produced ash clouds that rose to unknown heights. No ash was visible on satellite imagery. Based on JMA information, the Tokyo VAAC reported that explosions on 26 March at 1715 and 27 March at 0607 produced plumes that extended S and rose to ~2.5 km and ~2 km altitude, respectively.

An eruption on 17 April produced a gas-and-ash plume that rose to ~3 km altitude and extended W. Another eruption on 25 April produced an ash plume that rose to ~2.4 km altitude. and extended N. The Tokyo VAAC reported, based on information from the JMA, that an eruption occurred on 28 April at 1820. It produced a plume that rose to ~2.4 km altitude and drifted SE. No ash was visible on satellite imagery.

According to the Har-Tass news agency, JMA reported a powerful ash-bearing discharge on 15 May at 1107. Specialists stated that the activity was the most intensive in four years. There were no reports of damage or injuries. The explosion registered as 'large' on the JMA's scale for both the sound and the strength of the tremor it caused, according to a quoted official at the local agency office in Kagoshima.

The Tokyo VAAC said the ash plume rose to more than 1.8 km altitude. An explosion occurred on 17 May at 1946, sending an ash plume to a height of 2.1 km altitude. On 18 May a pilot reported ash at a height of ~1.2 km altitude and ~23 km S of the Amori region. During 19-24 May, several explosions produced ash clouds. The highest reported ash cloud reached ~2.4 km altitude on 24 May. An explosion on 20 June at 1523 produced an ash cloud that rose to an unknown height.

Information Contacts: Naokuni Uchida, Japan Meteorological Agency (JMA), Fukuoka, Japan (URL: http://www.jma.go.jp/); Tokyo Volcanic Ash Advisory Center (VAAC) (URL: https://ds.data.jma.go.jp/svd/vaac/data/).


June 2006 (BGVN 31:06) Citation IconCite this Report

First eruption outside of the summit crater in 58 years

According to Yukio Hayakawa, on 4 June 2006 Sakura-jima erupted. The vent, which was outside the summit crater, was near or within the crater which issued the 1946 (Showa) lava flow, on the E slope of Minami-dake summit. The eruption continued intermittently until the next morning. A small amount of ash fell in Kagoshima city. In the following days it became calm.

Aviation reports noted that ash clouds that reached unknown heights. No ash was visible on satellite imagery.

On 10 June, the Sakura-jima Volcano Research Center reported an increase in low-frequency earthquakes since mid-March and in small tremors with a less than 2 minute duration since mid-May 2006. A thermal anomaly at the volcano grew in size after February 2006.

This was the first reported Sakura-jima eruption from a vent outside the summit crater in 58 years. The 1946 vent was the source of major lava flows that reached the E and S coasts of the former island.

Our last Sakura-jima report noted the frequent ash plumes and eruptions through May 2004 (BGVN 29:05). The Tokyo Volcanic Ash Advisory Center's reports enabled an overview of ash plumes during mid-2005 to mid-2006 (table 13).

Table 13. Sakura-jima plumes during 2 June 2005-19 June 2006. Courtesy of the Tokyo VAAC.

Date Event Plume Type, Height, and Drift
02 Jun 2005 explosion Ash; unknown height
08 Jul 2005 explosion --
10 Jul 2005 explosion --
13-19 Jul 2005 explosion ~1.8 km height; drifting N
21 Jul 2005 explosion --
22 Jul 2005 explosion --
02 Sep 2005 eruption Ash; ~2.1 km high; drifting NW
09 Dec 2005 explosion ~2.7 km height; drifting S
05 Feb 2006 explosion ~1.8 km height; drifting N
19 Apr 2006 explosion ~2.4 km height; drifting NE
28 Apr 2006 explosion Ash; 2.1 km height
01 May 2006 explosion --
04-05 Jun 2006 intermittent Ash clouds; 200-300 m height, unknown drift eruptions
07-12 Jun 2006 -- Ash; unknown height, drift
14, 16, 19 Jun 2006 -- Ash; 2.1 km height

Information Contacts: Hayakawa Yukio, Gunma University, 4-2 Aramaki-machi, Maebashi City, Gunma, 371-8510, Japan; Tokyo Volcanic Ash Advisory Center (VAAC), Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL: https://ds.data.jma.go.jp/svd/vaac/data/); Sakura-jima Volcano Research Center, Disaster Prevention Research Institute (DPRI), Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan (URL: http://www.dpri.kyoto-u.ac.jp/).


April 2007 (BGVN 32:04) Citation IconCite this Report

Eruption from E-slope Showa crater on 4 June 2007

According to the Sakurajima Volcano Research Center (SVRC) at Kyoto University, an eruption started on 4 June 2006 at the Showa crater, a spot that differs from vents active in recent decades at the summit of Minami-dake ("south mountain"; BGVN 31:06 and many previous reports). The Showa crater resides on the E slope of Minami-dake at an elevation of ~ 800 m (figures 23, 24, and 25). Showa crater was formed in a 1946 eruption; the 1946 vent was the source of lava flows that spread E and then branched to travel S and ENE (figure 25).

Figure (see Caption) Figure 23. Map images showing Sakura-jima stratovolcano and environs on Japan's Kyushu island (~ 1,000 km S of Tokyo). (left) Image from Google Earth showing the S end of Kyushu Island. Population centers are labeled. Sakura-jima forms the dominant topographic feature in Kagoshima Bay. The Osumi Peninsula is to the E; the Satsuma Peninsula to the W. (right) Image from Google Earth showing terrain features looking NW towards the upper portions of Kagoshima Bay. Courtesy of Google Earth.
Figure (see Caption) Figure 24. A sketch map focused on the geologic context of Sakura-jima, the Aira caldera, and adjacent calderas. The Kagoshima graben forms the Bay of the same name. The graben also lies coincident with several caldera margins. Sakura-jima resides at the S portion of Aira caldera. Modified slightly from Okuno and others (1998).
Figure (see Caption) Figure 25. A geological map of Sakura-jima shown with several key features and eruptive dates labeled. Topographic highs from N to S include Kita-dake (K), Nika-dake (N), and Minami-dake (M). Craters at the summit of Minami-dake have been the active in past decades, but the eruption that started on 4 June eruption vented at Showa crater (S). An E flank lava flow (the Taisho Lava of 1914-1915) joined what had been an island's SE side to the shore (arrow at lower right labeled "j" aims at the zone of contact). Fringing the roughly circular former island are several areas of submarine volcanic and intrusive deposits (labeled here with the abbreviation "subm."). For example, the large area budding NE from the island consists of submarine and intrusive rocks of 1779-1780. Many of the Holocene eruptive deposits are dacites and andesites. They commonly bear pyroxene (and also sometimes, olivine). Besides lava flows, deposits include welded air-fall and pyroclastic-flow deposits (in some cases showing rheomorphosed textures indicative of movement downslope after forming a welded mass). From the Geologic Survey of Japan, AIST website (after Fukuyama and Ono, 1981 and Kobayashi, 1988).

Unfortunately, at press time many details still remained unavailable to Bulletin editors regarding the duration and character of the return of venting at Showa crater. It is also unclear to what extent the Minami-dake summit craters continued to participate in the emissions.

The 4 June 2006 eruption continued intermittently, including an evening eruption on 7 June which sent an ash column ~ 1 km above the crater. Figure 26 shows one such eruption on 6 June.

Figure (see Caption) Figure 26. A photograph of Sakura-jima erupting at 1231 on 6 June 2006 from Showa crater. Courtesy of SVRC, Disaster Prevention Research Institute, Kyoto University.

A series of plots describe the short- and long-term seismicity and volume of magma supplied at Sakura-jima (figures 27 and 28). The number of shallow earthquakes had increased since the middle of March 2006 (figures 26 and 27), and small volcanic tremors with a duration shorter than 2 minutes had increased since the middle of May 2006. GPS data showed continued inflation in the N part of the Aira caldera, an observation attributed to incoming magma. Kazuhiro Ishihara, director of SVRC, commented that the present eruption was considered to be related to magma accumulating in the Aira caldera and searching for an exit.

Figure (see Caption) Figure 27. A multi-year (1995 to mid-2006) view of Sakura-jima's activity: (top) monthly A-type earthquakes, (middle) monthly number of explosions (determined geophysically, exact method undisclosed), and (bottom) the cumulative volume of magma supplied. Courtesy of SVRC, Disaster Prevention Research Institute, Kyoto University.
Figure (see Caption) Figure 28. Plot of the daily number of volcanic earthquakes at Sakura-jima for the period 1 January-7 June 2006. Courtesy of SVRC, Disaster Prevention Research Institute, Kyoto University.

Table 14 presents a chronology of ash-plume observations made since the previous Bulletin report (BGVN 31:06). The table is based primarily on reports from Tokyo Volcanic Ash Advisory Center (VAAC) and covers the interval 7 June 2006 to 20 March 2007. Most of the plumes described did not exceed 3 km altitude. The tallest plume recorded on the table, an ash plume on 20 March 2007, rose to 3.7 km altitude.

Table 14. Heights and drift of plumes and their character at Sakurajima from June 2006-March 2007. Some of the data during mid-June 2006 were previously reported, but new information has emerged. Courtesy of SVRC and Tokyo Volcanic Ash Advisory Center.

Date Plume altitude/drift Other observations
07-12 Jun 2006 3.4 km --
10 Jun 2006 -- SVRC reported increase in low-frequency earthquakes since mid-March and in small tremors with a less than 2-minute duration since mid-May 2006; thermal anomaly at the volcano grew in size after February 2006.
14, 16, 19 Jun 2006 2.1 km --
02 Aug 2006 2.4 km/SW explosion
09 Aug 2006 2.4 km/straight up eruption
22, 23, 26 Aug 2006 2.4 km/SW eruptions
03-04 Sep 2006 2.7 km/NW and N eruptions
06 Sep 2006 -- explosion generated eruption cloud
19 Sep 2006 3 km/straight up eruption
20, 21 Sep 2006 2.4 km eruptions
07, 08, 10 Oct 2006 1.8-2.4 km/W, S, and SW eruptions
21 Oct 2006 3.4 km/straight up explosions
25 and 27 Oct 2006 2.1-2.4 km/SW and NE ash plumes
04-05 Nov 2006 2.1-2.4 km/NE, SE, E eruptions
22 Nov 2006 2.1 km/W explosions
26 Nov 2006 -- eruption
12 Dec 2006 2.1 km/NE eruption
13 Dec 2006 -- explosion
02 Jan 2007 3.4 km/SW eruption
10 Feb 2007 -- explosion
13 Feb 2007 2.1 km explosion
15 Feb 2007 1.5 km ash plume
20 Mar 2007 3.7 km ash plume

Volcanic hazards research. Lee and others (2005) reported the successful remote measurement of significant amounts of ClO (as well as BrO and SO2) in a volcanic plume from Sakura-jima during May 2004. Near the volcano they also observed halogen-catalyzed, local surface ozone depletion. The investigators employed ground-based, multi-axis, differential optical absorption spectroscopy. Their results help document the presence of a wide range of chemical species that have potential health implications for populations living nearby.

The center of Kagoshima City (population ~ 550,000) sits ~ 10 km from Minami-dake's summit and ~ 4 km from Sakura-jima's E shore (just off figure 24, but along the trend of the arrow labeled KC). According to Durand and others (2001), "Since 1955 the city has been subjected to ashfall from Sakura-jima. Until 1990 ashfalls occurred up to twice per week, although this has decreased in frequency in recent years."

Durand and others (2001) comment that "[Kagoshima City] presents a good opportunity to study the impacts of volcanic ash on key services, or 'lifelines.' In addition, the city provides a chance to see how lifelines have been adapted to counter any problems presented by ashfalls." They also noted that, "The advice from Kagoshima would seem to be that during an ashfall event, people should bring in the washing and shut the doors and windows. People who have to go out and work in ashfall should wear goggles and a face mask. In Kagoshima, umbrellas are the only form of protection for many people going to work during ashfall events."

References. Durand, M.; Gordon, K .; Johnston, D. ; Lorden, R. ; Poirot ,T. ; Scott, J. ; and Shephard, B.; 2001; Impacts of, and responses to ashfall in Kagoshima from Sakurajima Volcano?lessons for New Zealand. Science report 2001/30, Institute of Geological & Nuclear Sciences; Lower Hutt, New Zealand, November 2001 53p. (ISSN 1171-9184, ISBN 0-478-09748-4).

Fukuyama, H. and Ono, K., 1981, Geological Map of Sakura-jima, scale 1:25,000

Kobayashi, Tetsuo, 1988, Geological Map of Sakurajima Volcano, A Guidebook for Sakura-jima Volcano, in Kagoshima International Conference on Volcanoes, 1988 (1:50,000).

Lee, C., Kim, Y. J., Tanimoto, H., Bobrowski, N., Platt, U., Mori, T., Yamamoto, K., and Hong, C. S., 2005, High ClO and ozone depletion observed in the plume of Sakurajima volcano, Japan, Geophysical Research Letters, v. 32, L21809, doi:10.1029/2005GL023785.

Okuno, Mitsuru; Nakamura, Toshio, and Kobayashi, Tetsuo, 1998, AMS 14C dating of historic eruptions of the Kirishima, Sakura-jima and Kaimon-dake volcanoes, Southern Kyushu, Japan. Proceedings of the 16th International 14C Conference, edited by W. G. Mook and van der Plicht, RADIOCARBON, Vol. 40, No. 2, 1998, P. 825,832.

Information Contacts: Sakura-jima Volcano Research Center, Disaster Prevention Research Institute (DPRI), Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan (URL: http://www.dpri.kyoto-u.ac.jp/~kazan/default_e.html); Tokyo Volcanic Ash Advisory Center (VAAC), Japan Meteorological Agency (JMA) (URL: http://ds.data.jma.go.jp/svd/vaac/data/).


March 2009 (BGVN 34:03) Citation IconCite this Report

Recent (2007-2009) explosive eruptions and intermittent plumes

Our last reports on Sakura-jima (BGVN 31:06 and 32:04) discussed an eruption from Showa crater on 4 June 2006, the first eruption outside the summit crater since 1946. It also provided a chronology of plume observations between 7 June 2006 and 20 March 2007.

The current report continues the chronology of plume observations from 20 March 2007 to 24 April 2009 (table 15). Most of the plumes described since 20 March 2007 did not exceed 3 km altitude (figure 29). The tallest plume recorded on the table, an ash plume on 9 April 2009, rose to about 5 km altitude.

Table 15. Heights and drift of plumes and their character at Sakura-jima from 20 March 2007 to 24 April 2009. Courtesy of Tokyo Volcanic Ash Advisory Center, pilot reports, and the Japan Meteorological Agency (JMA). Times and dates are local.

Date Plume altitude/drift Observations
16 May 2007 1.2-2.7 km/ NW --
20-22 May 2007 1.2-2.7 km/ up --
23-24, 26-28 May 2007 1.8-2.1 km/ E, SE, up --
31 May-01 Jun 2007 2.1-2.4 km/ up --
04 Jun-05 Jun 2007 2.1-2.4 km/ W, NW, E Ash not detected by satellite imagery.
08, 10, 11 Jun 2007 2.1 km/ S Ash not detected by satellite imagery.
16 Jun 2007 -- Explosion. Ash not detected by satellite imagery.
20-21 Jun 2007 2.4 km/N Ash not detected by satellite imagery.
04 Aug 2007 -- Explosion. Ash not detected by satellite imagery.
29 Oct 2007 3.7 km/E --
23-24 Dec 2007 2.7 km/S --
02, 07 Jan 2008 -- Explosions reported.
03 Feb 2008 1.5-2.7 km/ SE Ash not detected by satellite imagery.
05-06 Feb 2008 1.2-2.1 km/ SE Ash not detected by satellite imagery.
11-15 Apr 2008 2.1-3.4 km/ various --
19 Apr 2008 4.6 km/E Plume contained ash.
20, 23-30 Apr 2008 2.4 km/various --
06-07 May 2008 2.4-3.4 km/S --
08 May 2008 4 km/E --
15-22 May 2008 1.8-3.4 km/various --
24 May 2008 -- Explosion reported.
30 May-01 Jun 2008 2.1-3 km/various --
09 Jun 2008 2.1 km/S --
10-11 Jun 2008 -- Explosions reported.
12-13 Jun 2008 3.4 km/various Plumes contained ash.
28 Jun 2008 -- Explosion reported.
05 Jul 2008 2.7 km/E --
10, 13 Jul 2008 2.7 km Plumes contained ash.
25-28 Jul 2008 2.4-4.3 km/various Plumes contained ash.
10 Aug 2008 >2.7 km/NW --
23 Aug 2008 -- Explosion reported.
07 Sep 2008 2.1 km/straight up --
03 Oct 2008 2.7 km --
09, 15 Jan 2009 2.4, 1.8 km/SE --
28 Jan -03 Feb 2009 1.8-3.4 km/various --
01-02 Feb 2009 -- Eight eruptions; bombs up to 800 m from Showa crater. On 2 Feb, JMA Alert level to 3.
04-05 Feb 2009 2.1-2.4 km/SE Explosions and eruptions.
09-12 Feb 2009 0.6-2.4 km/SE Ash plumes.
19 Feb 2009 -- JMA lowered Alert Level to 2.
22 Feb 2009 2.7 km/N Explosion.
28 Feb-04 Mar 2009 1.8-3 km/S Eruptions or explosions, three Vulcanian explosions from Showa crater ejected bombs up to 1.3 km. Deformation; expansion of edifice (tiltmeter). On 2 Mar, JMA Alert Level to 3.
07-10 Mar 2009 1.8-2.9 km/N, S Twelve Vulcanian explosions from Showa crater. Ejected bombs up to 1.8 km.
14 Mar 2009 1.5-2.1 km/SE, E Two Vulcanian explosions ejected bombs up to 800 m.
17 Mar 2009 2.1 km/E Eruption.
20, 23 Mar 2009 -- Explosions; weak incandescence on 23rd.
26 Mar 2009 -- Eruption.
27-30 Mar 2009 2.1 km/SE Weak eruptions, strong steam emissions.
05-07 Apr 2009 2.1-3 km/SE, S Explosions and eruptions.
08 Apr 2009 2.7 km Eruption.
09 Apr 2009 ~5 km/SW Vulcanian explosion, pyroclastic flow to 1 km E, bombs to 1.3 km, heavy ashfall at Kagoshima City.
10 Apr 2009 2.1-2.7 km/W, S --
24 Apr 2009 -- JMA lowered alert level to 2.
Figure (see Caption) Figure 29. Aerial photograph taken from the W of a plume from Sakura-jima's Showa crater as seen on 10 March 2009. Courtesy of JMA.

On 19 February 2009 JMA lowered the Alert Level from 3 to 2, because after the 1-5 February explosions, no eruptions had occurred either from Showa crater or Minamidake summit crater, seismicity was low, and no crustal deformation was observed (figure 30). As a result of heightened activity, the Alert Level was raised to 3 on 2 March, but dropped to 2 on 24 April 2009 due to low seismicity, lack of deformation, and absence of large eruptions. According to JMA, the shape of Showa crater has not changed recently, but the depth of the crater had increased. Photographs taken during an overflight on 10 March 2009 (figures 31 and 32) showed changes in morphology and temperature.

Figure (see Caption) Figure 30. Sakura-jima tilt recorded at Arimura during February 2009. The vertical axis indicates the sense and magnitude of movement. Data from Osumi Kasen Kokudo (Japan's Ministry of Land, Infrastructure, Transport and Tourism). Courtesy of JMA.
Figure (see Caption) Figure 31. A comparison of the morphology of Sakura-jima's Showa crater: (top) 28 July 2008, (bottom) 10 March 2009. Courtesy of JMA.
Figure (see Caption) Figure 32. N-looking infrared photo of Sakura-jima's Showa crater on 10 March 2009. Scale at right shows the estimated temperature (°C). Note the high temperature in Showa crater. The crater rim at higher elevation (upper left) is called Minami-dake ("M" on the geologic map in the previous issue). Courtesy of JMA.

An article in Asahi newspaper contained several photos of the 9 April 2009 ashfall in Kagoshima City, about 10 W of Sakura-jima. This was the heaviest ashfall since October 2002.

During the last two years, the only thermal anomaly recorded by MODIS-MODVOLC for Sakura-jima was on 17 December 2008 (1 pixel).

Two recently published articles (citations below) describe the mechanism of explosive eruptions at Sakura-jima and two other Japanese volcanoes, and color measurements of Sakura-jima's ash deposits.

References. Iguchi, M., Yakiwara, H., Tameguri, T., Hendrasto, M. and Hirabayashi, J., 2008. Mechanism of explosive eruption revealed by geophysical observations at the Sakurajima, Suwanosejima and Semeru volcanoes: Journal of Volcanology and Geothermal Research, v. 178, no. 1, p. 1-9.

Yamanoi, Y.,Takeuchi Y., Okumura S., Nakashima S., and Yokoyama, T., 2008. Color measurements of volcanic ash deposits from three different styles of summit activity at Sakurajima volcano, Japan: Conduit processes recorded in color of volcanic ash: Journal of Volcanology and Geothermal Research, v. 178, no. 1, p. 81-93.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Hawai'i Institute of Geophysics and Planetology (HIGP) Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Yukio Hayakawa, Gunma University, Faculty of Education, Aramaki 4-2, Maebashi 371-8510, Japan; Asahi newspaper (URL: https://www.asahi.com/).


August 2009 (BGVN 34:08) Citation IconCite this Report

May-October 2009, ongoing explosive eruptions

Our last reports on Sakura-jima (BGVN 31:06, 32:04, and 34:03) provided maps as well as a chronology of plume observations on this very active stratovolcano for the interval between 7 June 2006 and 24 April 2009. A small pyroclastic flow occurred on 9 April 2009.

The current report continues the chronology of plume observations from 3 May to 3 October 2009 (table 16). Most of the plumes described since 20 March 2007 did not exceed 3 km altitude. The tallest plume recorded in the table, an ash plume on 30 May 2009, rose to about 4.6 km altitude. The 3 October eruption from Minami-dake crater was described as violent. From 1 January through 30 September 2009, no thermal alerts were recorded by MODVOLC.

Table 16. Heights and drift of plumes and their character at Sakura-jima from 3 May 2009 to 29 September 2009. Courtesy of Tokyo Volcanic Ash Advisory Center, pilot reports, and the Japan Meteorological Agency (JMA). Dates are local.

Date Plume altitude/drift Observations
03 May-04 May 2009 2.4-3.7 km Eruptions
09 May 2009 2.1-3 km/S Eruptions
12 May 2009 1.8 km/E Eruptions
19 May 2009 2.7 km/SE Eruptions
26 May 2009 2.7 km/NW Eruptions
30 May 2009 4.6 km/SE Explosion
31 May-01 Jun 2009 2.1-3.4 km/S Eruptions
07 Jun 2009 3 km Eruption
09 Jun 2009 2.4 km/N Eruption
12 Jun 2009 1.8 km --
14 Jun-16 Jun 2009 2.4-2.7 km/SE, E Eruptions
24 Jun-30 Jun 2009 2.1-3.4 km/various Explosions
02-04, 06-07 Jul 2009 2.1-2.7 km/various Explosions
08, 10-15 Jul 2009 1.8-3.4 km/NE, E Explosions
15-22 Jul 2009 1.8-2.7/various Explosions. On 18-19 July airwaves exceeding 100 Pa were observed 3 km SW of the Showa crater. On 19 July, JMA raised the alert level to 3.
23, 27 Jul 2009 2.1-3/E, SW --
24-25, 28 Jul 2009 -- Explosions
31 Jul-04 Aug 2009 2.1-3.4 km Explosions
05 Aug-10 Aug 2009 1.8-4 km/various Explosions, eruptions
12 Aug-17 Aug 2009 2.1-2.7 km/E, N Explosions, eruptions
19 Aug-25 Aug 2009 2.1-3 km/various Explosions
26-29 Aug, 01 Sep 2009 1.2-3.4 km/various Explosions
02 Sep-08 Sep 2009 1.2-2.7 km/various Explosions
09 Sep-15 Sep 2009 1.5-2.7 km/various Explosions
16, 18-19, 21 Sep 2009 1.5-2.7 km/various Explosions
23, 25, 27-29 Sep 2009 1.8-2.7 km/various Explosions
03 Oct 2009 3 km Explosions at Minami-dake and Showa

Late 2009 activity. According to JMA, Sakura-jima exploded violently from the Minami-dake crater at 1645 on 3 October 2009. The resulting Vulcanian plume rose up to 3 km above the crater and ballistics reached as far as 1.7 km away from the crater. This explosive eruption was the first from Minami-dake crater since 22 February 2009. The Showa crater was also active on the night of 2-3 October. Several explosions were observed then, and red hot materials were ejected up to 800 m from the rim.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); MODVOLC, Hawai'i Institute of Geophysics and Planetology (HIGP) Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); Yukio Hayakawa, Gunma University, Faculty of Education, Aramaki 4-2, Maebashi 371-8510, Japan.


October 2011 (BGVN 36:10) Citation IconCite this Report

During 2011, pyroclastic flows, frequent ash plumes, and lava emission

Our last report covered the explosive eruptions of 2-3 October 2009 from two of Sakura-jima's active vents: Minami-dake and Showa (BGVN 34:08) (figure 33). Minami-dake was last active on 22 February 2009. This report covers Sakura-jima's activity from October 2009 through October 2011; datasets may have various termination dates due to availability.

Figure (see Caption) Figure 33. Location of Sakura-jima; surrounded by Kagoshima Bay and connected to the mainland of Kyushu, Japan by lava flows from 1914 AD (SW side of the island). Satellite image courtesy of Japan Aerospace Exploration Agency (JAXA) and index map from MapsOf.net.

The ash plumes of October 2009 to October 2011 reported by the Tokyo Volcanic Ash Advisory Center (VAAC) were disclosed in pilot's reports and satellite observations. Plume heights had a maximum altitude range of 1.2 to 4.9 km. VAAC released regular advisories during this time period, often more than once each week.

For the next 11 months following the explosive 2-3 October 2009 events, the Japan Meteorological Agency (JMA) maintained Alert Level 3 status due to intense eruptions from Showa crater (figure 34). The five-tier alert system used by JMA assigns red alert to Level 5; a Level 3 status forbids anyone to approach the volcano. Activity was occasionally Strombolian and Vulcanian during this time period. Lava fountaining on 8 February 2010 reached 1,000 m above the crater; this activity was visible at night and lightning was observed within the ash plume.

Figure (see Caption) Figure 34. Plume heights and documented explosions for Sakura-jima's primary eruptive vents: Minami-dake (top) and Showa (bottom). Data is plotted for January 2009 through July 2011. Courtesy of JMA.

On 30 May 2010 an ash plume rose 2.8 km from Showa crater. A small pyroclastic flow was documented on the E flank (figure 35). A camera located at the Ohsumi National Office of Rivers and Highways recorded the vertical plume and pyroclastic flow with both visible and thermal images. The pyroclastic flow traveled ~ 700 m and had temperatures up to 500°C above the background levels.

Figure (see Caption) Figure 35. An ash plume rose up to an altitude of 2.8 km from Sakura-jima's Showa crater and a pyroclastic flow traveled down the E flank. The eruption occurred at 1140 on 30 May 2010 and was captured by visual photography and a thermal camera. Courtesy of JMA.

Explosions were numerous in 2010 and according to JMA, by 20 June a new record had been reached; 550 explosions had already occurred at Sakura-jima. The Japan Times reported that the previous record high in a single year was 548 in 2009. By September 2010, this activity was less vigorous; the plumes from Showa crater were frequently less than 1 km high and no additional activity was reported from Minami-dake. On 30 September, JMA reduced the Alert Level but maintained warnings that no one should approach the summit craters. Earthquakes and tremor had become rare and constant deflation was recorded by tiltmeter and GPS. By June 2010, the long trend of inflation recorded by the water-tube tiltmeter at Arimura station peaked and in early July, abruptly began measuring deflation (figure 36).

Figure (see Caption) Figure 36. Tilt change at Sakura-jima observed by the water-tube tiltmeter at Arimura station from January 2009 to September 2011. Tidal response was corrected and inflation at the summit corresponds to positive tilt. In the bottom panel, the red bars denote monthly frequencies of explosions from Showa crater. Courtesy of JMA.

From 7 to 20 October 2010, explosive eruptions became more frequent and exceeded background levels from the previous month. A large explosion on 13 October produced ejecta that reached ~ 1.3 km from Showa crater. Earthquake activity was consistently low, but elevated levels of tremor were recorded prompting JMA to raise the Alert Level to 3. During the subsequent months, explosive, ash-rich plumes became more frequent, increasing from 59 in November, and 62 in December, to 102 in January.

Activity was concentrated within the Showa crater until February 2011 when renewed activity began simultaneously at Minami-dake. Last active on 3 October 2009, the summit crater of Minami-dake released two ash-rich plumes on 7 February 2011. Volcanic bombs from Showa crater landed 0.8-1.3 km from the crater. At 1908 on 19 February, a pyroclastic flow extended ~ 500 m down the SE flank. JMA recorded 144 explosions that month, 110 of these events produced ash.

Incandescence and pyroclastic flows from Showa crater. Explosive eruptions continued at a lower rate during the following months; observers however, noted incandescence from Sakura-jima's summit from March through September 2011. An explosive eruption at 2242 on 30 April was recorded from Showa crater and was accompanied by a pyroclastic flow that extended 600 m from the crater on the E flank. Smaller pyroclastic flows 200-400 m in length occurred on 5 June, 12 July, and 1 and 12 September. These events traveled E and SE from the Showa crater and were recorded by thermal cameras and observers.

Aerial surveillance. Aerial observations of Showa crater were made on 31 May 2011 by JMA in cooperation with the Japan Maritime Self Defense Force (JMSDF). Fresh lava was discovered covering part of the crater floor with a diameter of 50-60 m (figure 37). Thermal results determined that the hottest area was in the center of the lava with temperatures up to 500°C above the measured background.

Figure (see Caption) Figure 37. Sakura-jima's Showa crater on 31 May 2011. Aerial observations (A) and thermal imaging (B) determined the presence of new lava (appears black in plain light but has a high thermal output). Courtesy of JMA-JMSDF.

During the 31 May overflight, two ponds of water were identified within the Minami-dake vent. Both craters, A and B, contained water (figure 38) that persisted through 11 July, and by August the volume of water appeared to have increased in crater A. Observations from an aerial survey on 30 August found the ponds differed in color: Crater A appeared light blue, and Crater B was red-brown. There was no apparent change in the amount of degassing from these craters.

Figure (see Caption) Figure 38. Sakura-jima's Minami-dake vent on 31 May and 11 July 2011. Aerial observations determined that water was collecting in craters A and B. Activity had not been recorded from this site since 7 February 2011. Courtesy of JMA-JMSDF.

Information Contacts: Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); JAXA (URL: http://www.eorc.jaxa.jp/en/earthview/2011/tp110223.html); MapsOf.Net (URL: http://mapsof.net/).


May 2012 (BGVN 37:05) Citation IconCite this Report

Explosions during November 2011-July 2012; ash and health

This report provides highlights of activity at Sakura-jima during November 2011-July 2012 (following the previous report in BGVN 36:10). Over this interval, activity was characterized by consistent explosive eruptions that generated many plumes. Inflation of the edifice occurred over the first few months of the reporting period. Information was provided by the Japan Meteorological Agency (JMA) and the Tokyo Volcanic Ash Advisory Center (VAAC), unless otherwise noted. This report concludes with recently published research on the health consequences of exposure to ash erupted from Sakura-jima.

November 2011-July 2012. The reporting interval of the previous Bulletin report ended in a period of deflation of Sakura-jima's edifice (BGVN 36:10, covering through October 2011). Coincidentally, JMA reported that Sakura-jima entered a period of inflation around the beginning of November 2011 (figure 39). That same episode of inflation continued through late January 2012, after which tilt measurements indicated little change through July.

Figure (see Caption) Figure 39. Explosions (number per month, top) and tilt measurements (microradians - ?rad, bottom) at Sakura-jima during January 2009-July 2012. During November 2011-July 2012, explosions occurred more than 50 times per month, and the volcano was inflating until late January 2012 (pale orange area), after which little deformation was measured on tiltmeters (pale green area). Courtesy of JMA.

JMA reported that explosive eruptions occurred on average at a rate of more than two explosions per day (figure 39) during November 2011-July 2012. Explosions from Showa Crater commonly ejected tephra and/or ballistics up to 1.3 km from the crater. Plumes were reported to have risen 1-3 km above sea level (a.s.l.) by JMA and Tokyo VAAC more often than weekly; occasional plumes rose to 4 km a.s.l, and on 22 and 24 June, plumes rose 6.1 km a.s.l. Many plumes may have been ash-bearing, but Tokyo VAAC does not report ash content unless citing a pilot report (usually about once a week at Sakura-jima during the reporting interval). Noted exceptions from the common eruptive behavior over this reporting interval are explosions which ejected tephra up to 2 and 1.8 km from Showa Crater on 12 March and during 18-21 May 2012, respectively, and an explosion from Minami-dake Crater on 24 July that ejected ash up to 1.7 km from the crater. Pyroclastic flows traveled 200-300 m down the flanks of Showa Crater on 21 May and between 4 and 8 June.

Richard Roscoe, a visitor to the volcano, photographed Showa Crater in April 2012, and noted that it was ~20% wider in the N-S direction as compared with early 2010 (figure 40).

Figure (see Caption) Figure 40. A photograph of Sakura-jima's Showa Crater taken in early April 2012, looking W. Richard Roscoe, the photographer, noted that the crater was ~20 % wider in the N-S direction than it was in early 2010. Courtesy of Richard Roscoe, Photo Volcanica.

Health effects of Sakura-jima ash. Hillman and others (2012) characterized ash from Sakura-jima and possible health concerns due to exposure to the ash; they primarily sampled recently erupted ash, but also sampled older units up to ~500 years old (from 1914 and 1471-1476 A.D.) to assess possible health concerns in the event that Sakura-jima returns to previous eruptive styles, including Plinian explosive eruptions. Their analyses aimed to, among others, measure the amount of cristobalite (a silica polymorph known to cause respiratory diseases) in the ash, characterize the grain morphology of ash particles, assess the surface reactivity of the particles, and test the potential of ash particles to cause hemolysis ? the rupturing of red blood cell membranes.

From their work, Hillman and others (2012) reported that all analyzed samples contained low concentrations of cristobalite compared to explosively generated ash at other volcanoes, and other silica polymorphs (quartz and tridymite) were not found. While a greater percentage of respirable ash is often generated during Plinian eruptions, the authors reported the lowest concentrations of cristobalite in ash from Plinian eruptive phases at Sakura-jima.

Morphologically, the authors found many respirable grains adhered to other particles. They also found nano-scale fibers, but reported that they were not related to asbestos in composition or morphology, and were of too low concentration to pose a respiratory hazard.

The surface reactivity of ash particles was reported to be low compared to other volcanoes, and Hillman and others (2012) concluded that "iron related reactivity, as a mechanism for disease, is unlikely at Sakura-jima volcano." They also reported that ash particles had a low-to-mild potential of causing hemolysis. They concluded that ash from Sakura-jima does not have a high potential of causing respiratory disease via the mechanisms studied, but stated that other potential sources of toxicity needed to be analyzed.

Reference. Hillman, S.E., Horwell, C.J., Densmore, A.L., Damby, D.E., Fubini, B., Ishimine, Y., and Tomatis, M. (2012) Sakurajima volcano: a physico-chemical study of the health consequences of long-term exposure to volcanic ash, Bulletin of Volcanology, 74:913-930 (DOI: 10.1007/s00445-012-0575-3).

Information Contacts: Japanese Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Richard Roscoe, Photo Volcanica (URL: http://www.photovolcanica.com/).


January 2014 (BGVN 39:01) Citation IconCite this Report

Frequent explosions during 2012-13; ashfall on Kagoshima City

This report summarizes activity at Sakura-jima (a cone within the Aira caldera) between August 2012 and December 2013. Data were largely provided by the Japan Meteorological Agency (JMA) and the Tokyo Volcanic Ash Advisory Center (VAAC). Monthly JMA reports of volcanic activity have been translated into English since October 2010. These reports can be viewed online (see reference section below).

Sakura-jima has been the subject of repeated reports here, many reporting recent explosions (BGVN 31:06, 36:10 and 37:05). Pepe and others (2013) remarked that at Sakura-jima, "Explosive eruptions of Vulcanian type, with ash emissions, have occurred intermittently from 1955 to 2002. From 2009 to December 2012, a strong and continuous period of volcanic activity has been recorded mainly at the Showa Crater producing plumes that reached altitudes of 1.8-3.5 km." JMA (2013) commented that resumption of eruptions at the Showa crater in June 2006 marked a return of activity at this vent after 58 years. It is also noteworthy that during this reporting interval no multi-week-long break in eruptions took place. In other words, the eruptions discussed below all took place within a larger a larger episode ongoing since 2006.

The locations of Sakura-jima and the nearby Kagoshima City are shown in figure 41. The city of Kagoshima sits 8 km W of the volcano and is home to over 600,000 residents. Sakura-jima has several craters, including the currently active Showa crater and the Minamidake crater (figures 42 and 43).

Figure (see Caption) Figure 41. (Larger map) Main islands of Japan showing location of Sakura-jima. (Inset map) Sakurajima with respect to Kagoshima City. Revised from an original by Jim Markowich and Sandy Mayer.
Figure (see Caption) Figure 42. Topographical map of Sakura-jima, which lies on the southern boundary of the 17 x 23 km diameter Aira caldera. Courtesy of Geospatial Information Authority of Japan (GSI).
Figure (see Caption) Figure 43. Topographical map of the central crater area of Sakura-jima, showing relationship of Showa and Minamidake craters. Map was based on 2010 aerial laser measurement (LIDAR) data. Courtesy of the Japanese Ministry of Ministry of Land, Infrastructure, Transport and Tourism, Osumi Office of River and National Highway (Kyushu Regional Development Bureau).

According to JMA, during this reporting interval (August 2012 to December 2013) eruptive activity at Showa crater remained high and volcanic seismicity remained relatively low (table 17). Earthquake hypocenters were located at depths ranging from 0-4 km below sea level under the volcano. The average sulfur dioxide fluxes taken during JMA field surveys were relatively high (800-4,100 metric tons/day, table 17).

Table 17. For the interval August 2012-December 2013 numerous eruptive events, including explosions, took place without significant hiatus. The number of eruptions, earthquakes, and tremor, and average sulfur dioxide fluxes measured monthly. "Total eruptions" include the explosive eruptions. Average SO2 levels are based upon 1-4 field surveys per month. Data compiled from JMA monthly reports. NR means not reported.

 Month Total eruptions Explosive eruptions Number of earthquakes Tremor Average SO2 level (t/d)
August 2012 59 43 370 270 2,600-3,300
September 73 48 349 283 2,700-3,700
October 61 35 736 500 2,100-5,700
November 71 55 635 363 2,100-2,200
December 55 43 813 453 1,200-1,400
January 2013 124 96 1,058 230 1,700-4,100
February 132 119 746 321 800-1,900
March 74 61 552 321 2,800
April 17 14 287 56 1,600-2,300
May 70 58 NR NR 2100-3400
June 18 17 NR NR 2200
July 128 83 NR NR 1,600-2,200
August 144 118 NR NR 1,400
September 154 110 NR NR 2,200-2,900
October 127 87 NR NR 900-2500
November 69 50 NR NR 900-1,500
December 40 22 NR NR 1,700-1,800

Showa crater had frequent explosions that commonly ejected tephra and/or ballistics up to 1.3-1.8 km from the crater, according to JMA reports. During explosive eruptions from August 2012 through July 2013, ash plumes rose to a maximum height of 2 to 3.5 km above the crater rim. From August through November 2013, the maximum heights ranged from 4 to 5 km. The Tokyo VAAC issued numerous advisories during this reporting period. Occasionally, incandescence was observed at night with high-sensitivity cameras, and infrequently with the naked eye.

On 7 October 2012, a very small pyroclastic flow was observed for the first time since 6 June 2012; it flowed 300 m E. Small pyroclastic flows were also observed on 30 November and 26 December 2012, both of which flowed 500 m E. Very small pyroclastic flows were sporadically observed in 2013.

Table 18 shows the monthly ash fall measurements and the computed mass of ash falling in Kagoshima. The total amount of ashfall for 2012 was 6.6 million tons, compared to 4.5 million tons in 2011. The overall 2012 burden was the largest since the resumption of activity at Showa crater in 2006, As seen in table 18, during October 2013 an estimated 1 metric ton of ash fell on Kagoshima, the largest amount since the activity resumed at Showa crater in 2006.

Table 18. The mass of ash that fell on the city of Kagoshima during August 2012-December 2013. The measurements of density of ashfall burden were measured at the Kagoshima Local Meteorological Observatory (KLMO), 10 km W of Showa crater. The total estimated amount of ashfall on the City in millions of metric tons was estimated by the Kagoshima prefectural government. "NR" means not indicated in JMA monthly reports.

Month Measurement at observatory (KLMO) (g/m2) Total mass on City ( x 109 kg)
August 2012 142 0.34
September 194 0.4
October 153 0.3
November 137 0.5
December 13 0.5
January 2013 11 0.4
February 24 0.8
March 8 0.6
April 0.5 0.2
May 74 0.5
June 4 0.1
July 2 0.7
August 59 0.7
September 906 0.8
October 720 1.0
November 7 0.5
December NR NR

Larger explosions with greater effect occurred during August-November 2013. On 18 August 2013, an explosion produced a large plume that rose to 5 km above the crater rim and drifted NW (figure 44). According to a news account (Associated Press), the plume height was the highest since JMA starting keeping records in 2006. Ash fell over a wide area from Kagoshima City to Koshikijima Island (about 70 km WNW of Kagoshima City) in amounts large enough to cause suspension of public transportation in Kagoshima City (figure 45). The explosion produced a small pyroclastic flow that flowed about 1 km SE of Showa crater. This report quoted a Kagoshima official as saying that the 18 August explosion was Sakura-jima's 500th eruption that year.

Figure (see Caption) Figure 44. Photo of Sakura-jima on 18 August 2013, taken from Kagoshima City, looking E. Courtesy of AP Photo/JMA's Kagoshima Local Meteorological Observatory. The plume rose to 5 km above the crater rim (or about 6 km in altitude).
Figure (see Caption) Figure 45. E-looking view showing an ash plume from Sakura-jima on 18 August 2013 sweeping towards Kagoshima City. According to a news report (Associated Press), residents were urged to cover up and wear masks. Courtesy of AP Photo/Kyodo News.

On 29 August 2013, a large plume rose to 3 km above the crater rim and drifted ENE. Volcanic ash fell on an area from Sakura-jima Island to Miyazaki City (about 80 km NE of the volcano), and lapilli with a diameter of 1 cm fell on the Kurokamicho area of Kagoshima City (about 4 km E of Showa crater).

Another explosion on 4 September 2013 produced a relatively large plume that rose to 2.8 km above the crater rim and rapidly drifted S. Lapilli with diameters of up to 4 cm fell on small communities up to 3 km S of Showa crater, breaking the windows of more than ten cars and causing other damage. Smaller lapilli were found around Tarumizu City Hall (about 8 km SSE of the crater). A similar explosion on 25 September produced 2-cm lapilli that fell on another community about 3 km S of the crater, causing similar damage to car windows.

On 15 October 2013, lapilli with a diameter up to 3 cm fell on a community 3.5 km SW of Showa crater. Another explosion on 24 October resulted in 1-cm lapilli falling on a community about 5 km NW of the crater. Neither eruption caused any damage.

An explosion on 24 November 2013 produced a large plume that rose 4 km above the crater rim and drifted NE. Ash and 7-mm diameter lapilli fell on nearby communities. Lapilli with diameters of 1-1.5 cm also fell on a community 4 km SE of the crater on 18, 26, and 29 November.

Nearby Minamidake crater to the W of Showa crater was quiet during most months during the reporting period. According to JMA, Minamidake produced an occasional very small eruption beginning 20 October through the end of the year. In 2013, small eruptions were observed in January, August, November, and December.

Deformation. Pepe and others (2013) used satellite interferometry (InSAR) to create 44 interferograms for the years 2006-2012. They found the deformation complex, possibly the result of multiple inflation-deflation cycles. They stated, "The preliminary analysis of the mean deformation velocity reveals the presence of a consistent uplift signal in the North region of the Sakurajima Island that extends also to the North sector of Kagoshima bay. The corresponding deformation time series are characterized by a strong non-linear behavior. More specifically, the general uplift trend is found, interrupted by low amplitude subsidence phenomena. Finally, we argue that the complexity of detected deformation time series could be interpreted as the effect of cyclical periods of inflation and deflation."

Ground deformation measured with a water-tube tiltmeter installed 2.5 km SE of the Minamidake summit crater (by Japan's Ministry of Land, Infrastructure, Transport and Tourism, MLIT), found an almost static state after February 2012, changing around August 2012 to slight subsidence. During February 2013, this same instrument detected a slight uplift. Although other research groups deployed deformation instruments during this time, their data were not widely available.

In addition, JMA reported that an analysis of measurements of a satellite-based GNSS (Global Navigation Satellite System) suggested inflation around February 2013. In contrast, between July-December 2013, deformation was either almost negligible or slightly tended toward contraction.

Further background. More descriptive information is available in the National Catalog of the Active Volcanoes in Japan (JMA, 2013). The following extracts several key points from a much longer paragraph in that document. First, Sakurajima is an andesite-dacite composite volcano located on the southern rim of the Aira caldera. The SiO2 content of the rocks is between 56.5 and 67.2 wt %. Second, it is composed of two main cones-Kitadake and Minamidake-as well as numerous parasitic cones.

References: Japan Meteorological Agency, 2013 National Catalogue of the Active Volcanoes in Japan (The Fourth Edition, English Version), Japan Meteorological Agency (JMA), Accessed online June 2013 (URL: http://www.data.jma.go.jp/svd/vois/data/tokyo/STOCK/souran_eng/menu.htm)

Japan Meteorological Agency, Monthly volcanic activity reports (URL: http://www.data.jma.go.jp/svd/vois/data/tokyo/eng/volcano_activity/monthly.htm ).

Miwa, T, 2013, Temporal variation in volcanic ash texture during a vulcanian eruption at the Sakurajima volcano, Japan. Journal of Volcanology and Geothermal Research, v. 260.

Pepe, S., Trippanera, D., Casu, F., Tizzani, P., Nobile, A., Aoki, Y., Zoffoli, S., Acocella, V., and Sansosti, E., 2013, The 2006-2012 deformation at Sakurajima stratovolcano (Japan) detected via spaceborne multisensor SAR Interferometry, EGU General Assembly Conference Abstracts, 2013, Vol. 15, EGU2013, pp. 11748 (URL: http://adsabs.harvard.edu/abs/2013EGUGA..1511748P ).

Information Contacts: Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); Geospatial Information Authority of Japan (GSI) (URL: http://www.gsi.go.jp/ENGLISH/); Japan's Ministry of Land, Infrastructure, Transport and Tourism (URL: http://www.mlit.go.jp/en/index.html); and Associated Press (AP) (URL: https://www.ap.org/).


November 2015 (BGVN 40:11) Citation IconCite this Report

Explosions continue in 2014, averaging more than one eruption per day

Sakurajima volcano at Aira caldera in southernmost Japan has records of historical eruptions back to the 8th century; it was very active in 2012 and 2013, and eruptive activity continued during 2014 with explosions and pyroclastic flows that have been ongoing since 1955. The Showa crater near the summit returned to activity in 2006 and has been the primary active vent since that time. The Japan Meteorological Agency (JMA) provides monthly reports on activity, and the Tokyo VAAC (Volcanic Ash Advisory Center) issued hundreds of reports about ash plumes during 2014.

JMA reported that Showa Crater erupted 471 times in 2014 (figure 46). This is less than half of the 1,097 eruptions reported for 2013, and is lower than average compared with the previous five years, but is also consistent with the periodic variation in eruptive frequency observed between 2009 and 2014 (figure 47).

Figure (see Caption) Figure 46. Number of eruptions during 2014 from Showa Crater on Sakurajima volcano at Aira caldera. Data from JMA Monthly reports.
Figure (see Caption) Figure 47. Number of monthly eruptions at Showa crater (red bars, top) on Sakurajima volcano at Aira caldera between 1 January 2009 and 31 January 2014. The lower graph represents the change in tilt observed with a water-tube tiltmeter at Arimura Station from January 2009 through January 2014 with tidal response eliminated. Inflation of the summit corresponds to positive tilts. Tilt values remained stable and changed little through 2014. Courtesy of JMA (Monthly Summary, January 2014).

Small pyroclastic flows that reached 400-600 m SE or E of Showa Crater were reported three times in 2014, on 22 January, 12 February, and 4 July. The Minamidake summit crater was generally quiet. Only one very small eruption was reported from it on 19 January, and a few very small eruptions were reported there in May. Incandescence was visible from the Showa crater, where virtually all the activity was focused, during several nights almost every week throughout the year.

Significant ashfall was reported by JMA for the 22 January eruption; the Central Fire Department of Kagoshima Fire Prevention Bureau reported that lapilli with a diameter of up to 1 cm fell on an area of Arimuracho in Kagoshima City (about 3 km S of the Showa crater) and larger lapilli with a diameter of 3 cm fell on the Arimura Observation Point (also about 3 km S of the Showa crater).

Most of the explosions during the year sent rocks to within 800 m of the Showa crater. Rocks were ejected as far as 1,300 m from the Showa crater in seven explosive eruptions in January, 12 times in February, 22 times in August, and eight times in October. Larger eruptions sent rocks even farther to distances up to 1,800 m from the crater on 9 March, twice in September, on 28 November, and on 8 and 11 December.

Ash plumes rising to an altitude of 2-3 km were reported weekly by Tokyo VAAC throughout the year. Most of the plumes drifted SE or S, but occasionally were observed drifting NE and other directions as well. Every month (except April) plumes also rose to heights of 3.7-4.6 km, and twice (in May and June) the highest plumes to 5.5 km were reported. A web camera in Tarumizu (12 km SE of Sakurajima) captured a typical ash plume on 24 October that rose to 4.6 km and drifted E (figure 48).

Figure (see Caption) Figure 48. Image from an unspecified webcam in Tarumizu, 12 km SE of Aira's Sakurajima volcano, of an eruption at 1211 local time on 24 October 2014. The ash plume rose to 4.6 km altitude and drifted E. Image archived by and courtesy of Volcano Discovery.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/); Tokyo Volcanic Ash Advisory Center (VAAC), Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Volcano Discovery (URL: https://www.volcanodiscovery.com/).


February 2018 (BGVN 43:02) Citation IconCite this Report

Explosions gradually decrease in frequency during 2015-2016

Sakurajima rises from Kagoshima Bay, which fills the Aira Caldera near the southern tip of Japan's Kyushu Island. Frequent explosive and occasional effusive activity has been ongoing for centuries. The Minamidake summit cone has been the location of persistent activity since 1955; the Showa crater on its E flank has been the most active site since 2006. Tens of explosions and ash-bearing emissions have been occurring monthly for the last several years and were continuous through October 2015. After a three-month break, activity resumed in February 2016 and lasted through August 2016. No further activity was reported through December 2016. The Japan Meteorological Agency (JMA) provided regular reports on activity, and the Tokyo VAAC (Volcanic Ash Advisory Center) issued hundreds of reports about ash plumes during 2015-2016.

The number of explosive events at the Showa crater of Sakurajima increased from January-May 2015. During the period, ash emissions commonly rose 3,000 m above the crater rim, and a few exceeded 4,000 m; tephra was often ejected 1.3 km and as far as 1.8 km from the crater. Incandescence was observed every week; multiple MODVOLC thermal alerts were reported monthly from January-June 2015. The Tokyo VAAC issued 845 reports between 1 January and 14 October 2015. The number of monthly explosions decreased sharply during June-August. Tiltmeter and strainmeter data indicated continuing inflation through mid-August when the inflation rate increased significantly for a brief period. This was followed by deflation for the remainder of 2015. Pyroclastic flows were reported in March, April, and June. Minor emissions occurred at Minamidake crater in May, June, and August. Activity increased at both craters during September, with the first substantial explosion at Minamidake in almost a year. An emission from Showa on 2 November 2015 was noted in a JMA weekly report, but its composition was not described; the last confirmed ash emission of the year was on 14 October 2015.

After three months of quiet, a substantial explosion at Showa in early February 2016 marked the beginning of a new eruptive episode that continued through the end of July, after which explosive activity ceased at Showa for the remainder of the year (figure 49). Minor emissions were reported at Minamidake through August 2016. Pyroclastic flows occurred in April and June from explosions at the Showa crater. Inflation was measured again beginning in April 2016 and continued through December 2016.

Figure (see Caption) Figure 49. Explosions from the Showa crater at Sakurajima, January 2013-December 2016. Data do not include activity at Minamidake crater, or passive (non-explosive) ash or steam emissions from Showa. After many years of multiple monthly explosions, activity decreased in September 2015. A smaller burst of activity occurred from February to July 2016. Data compiled from JMA reports.

Activity during January-May 2015. JMA reported 61 explosions from the Showa crater during January 2015, twice the number recorded in December 2014 (figure 50). Explosions on 4 and 30 January sent ejecta as far as 1.8 km from the crater. The maximum plume height reported by JMA was 4,000 m above the crater rim on 23 January. Lapilli up to 2 cm in diameter from recent explosions were found in Kurokami (3.5 km E) and Arimura (3 km S) during JMA field visits on 16 and 30 January.

Figure (see Caption) Figure 50. An ash emission at Sakurajima on 20 January 2015 was captured by a webcam in Kagoshima (10 km W). Courtesy of Volcano Discovery.

The number of explosions increased to 88 during February 2015, with events on 21 and 22 February sending tephra 1.8 km from the crater. Plumes rose as much as 3,500 m above the rim during the month. During a field survey on 4 March scientists observed ash deposits with fragments up to 2 cm in diameter, in an area 3 km S of Showa Crater. JMA reported that the largest number of explosions they have recorded in a month, 178, occurred at the crater in March. Numerous plumes rose 3,300 m above the crater. A small pyroclastic flow on 17 March traveled 600 m SE.

Seismicity below the island increased briefly between 31 March and 2 April 2015. An explosion on 17 April sent tephra 1.8 km from the crater rim. Two pyroclastic flows were reported on 18 and 28 April 2015; Showa crater had 112 explosions throughout the month. The pyroclastic flow on 28 April travelled 500 m down the SE flank. The highest ash plume rose 4,000 m on 24 April. JMA calculated that about 1.2 million tons of ash fell during April, the largest monthly amount recorded since 2006.

Several of the 169 explosions at the Showa crater during May 2015 produced ejecta that was deposited up to 1.8 km from the crater. Many explosions had plume heights exceeding 3,000 m. A small emission, rising 200 m, was observed from the Minamidaki crater on 12 May and was the first in several months. JMA scientists observed 2-cm-diameter tephra in the vicinity of Kurojin-cho, Kagoshima-shi on 14 May, likely from an explosion the previous day; significant ashfall covered the ground as well. The highest ash plume of the month rose 4,300 m above the Showa crater on 21 May 2015 (figures 51 and 52).

Figure (see Caption) Figure 51. An ash plume rose 4,300 m above Sakurajima on 21 May 2015, shown in this webcam image from Kagoshima. Courtesy of Volcano Discovery.
Figure (see Caption) Figure 52. A dense plume of ash drifted S and E from Sakurajima on 21 May 2015. This natural-color satellite image was taken by the Operational Land Imager on Landsat 8. Courtesy of NASA Earth Observatory.

Activity during June-December 2015. Five of the 64 explosions recorded during June produced ejecta that landed up to 1.3 km from the Showa Crater (figure 53). A 3,300-m-high ash plume on 1 June was the highest for the month. After three explosions on 4 June, a small pyroclastic flow traveled 400 m down the E flank. A second small event on 22 June at Minamidake produced a gray plume that rose 200 m.

Figure (see Caption) Figure 53. Ash rose from Showa Crater at Sakurajima on 9 June 2015. Image taken by a drone managed by Naoto Yoshitome and Krishima Aerial Photography. Courtesy of Naoto Yoshitome, Twitter.

Activity decreased significantly beginning in July 2015, with 14 explosions reported from the Showa Crater, and declined further during August with only 5 explosions. A small explosion from the Minamidake crater on 16 July sent emissions likely containing ash (described as "non-white") to 200 m. A rapid increase in seismicity directly beneath Minamidake began on 15 August and lasted about 48 hours; along with tiltmeter and strainmeter observations of rapid inflation (figure 54), this led JMA to briefly raise the Alert Level from 3 (Do not approach the volcano) to 4 (Prepare to evacuate) an a scale of 1-5. They lowered it back to 3 on 1 September 2015. Only small explosions with tephra ejected up to 800 m were recorded during the rest of the August. Minor emissions occurred at Minamidake Crater on 30 August.

Figure (see Caption) Figure 54. An interference image of Sakurajima using PALSAR-2 high-resolution mode (3 m resolution) data comparing displacement between 4 January and 16 August 2015. The data showed a displacement toward the satellite (inflation) of about 16 cm maximum (within the white square), on the E side of the Minamidake summit crater. The synthetic aperture radar (PALSAR - 2) equipped with Daichi 2 (Land Observing Satellite No. 2 "Daichi 2" (ALOS- 2)) can measure the displacement of the ground surface (how much the ground moved) by taking the difference between two sets of observation data. Such an analysis method is called interference SAR analysis (or interferometry, InSAR). The color changes represent the differences in the two observations, a pattern of green to red to blue indicates movement of the surface towards the satellite (inflation); a pattern of green to blue to red indicates movement away from the satellite (deflation). Courtesy of JAXA (http://www.eorc.jaxa.jp/ALOS-2/img_up/jpal2_sakurajima_20150816-17.htm).

Incandescence at the Showa Crater was observed several times during September 2015; 46 explosive events were reported. The first significant explosions at the Minamidake summit crater since 7 November 2014 occurred on 13 and 28 September. The 28 September plume rose to 2,700 m above the crater rim. Tiltmeter data indicated no additional inflation since the rapid ground deformation of 15-16 August. The last explosive event of 2015 reported by JMA at the Showa crater was on 17 September and at the Minamidaki crater on 29 September.

The Tokyo VAAC reported an ash emission on 14 October 2015 that rose to 1.8 km and drifted SW. This was the last VAAC report until 5 February 2016. No explosions were recorded at the Showa crater in October, but minor ash emissions were reported on 14, 15, 21, 22, and 30 October. No activity was observed at Minamidake. Data from continuous GNSS (Global Navigation Satellite System) observations suggested that deflation began after the 15 August rapid inflation event.

A minor emission was reported by JMA from the Showa crater on 2 November 2015, the last emission reported for the year. After not having explosive activity since late September, JMA lowered the Alert Level to 2 (Do not approach the crater) on 25 November, reducing the exclusion area to 1 km around the two craters. Only steam plumes rising 50-200 m above the Showa crater and 50-600 m above the Minamidake crater were observed during December 2015.

Aerial observation on 2 December 2015 revealed 100-m-high steam plumes around the floor of the Showa crater. Thermal observations showed high heat flow around the edges and at the center of the crater floor, unchanged since the previous observation in August 2015; 200-m-high steam plumes around the Minamidake crater prevented observation of the crater floor.

Activity during 2016. No explosive activity was observed at Showa or Minamidake craters from October 2015 to 5 February 2016. JMA raised the Alert Level back to 3 after a substantial explosion on 5 February sent incandescent tephra up to 1.8 km from the Showa crater; lightning was observed in the ash cloud (figure 55). The Tokyo VAAC reported that an ash plume visible in satellite imagery was at 3 km altitude drifting SE. Multiple explosions continued from the Showa crater for the rest of February with ash plumes rising to 2.2 km above the crater, and tephra was frequently ejected 1.3 km from the crater. Four MODVOLC thermal alerts in February were the only alerts for 2016. At the Minamidake summit crater, minor emissions occurred on 8, 9, and 20 February with plumes rising 800 m above the crater rim.

Figure (see Caption) Figure 55. Incandescent tephra explodes from Showa crater at Sakurajima on 5 February 2016 after three months of inactivity. Photo by Kyoto News/AP. Courtesy of the Washington Post.

Eight explosions at the Showa crater were reported by JMA, and six at the Minamidake summit crater during March 2016. Ash plumes at Minamidake on 4, 8, and 11 March rose 1,600-1,900 m above the crater rim; on 25 and 26 March they rose 2,000 m. Minor emissions were also noted on 14 and 15 March. Three explosions from the Showa Crater on 26 March sent ash plumes 2,700 m high (figure 56); tephra as large as 8 mm in diameter was found in areas 4 km E.

Figure (see Caption) Figure 56. Multiple explosions on 26 March 2016 at Sakurajima sent tephra as large as 8 mm in diameter as far as 4 km from Minamidake crater. Image taken from a drone managed by Naoto Yoshidome. Courtesy of Naoto Yoshidome, Twitter.

Activity increased during April 2016 with 51 emission events that included 15 explosions at Showa, and JMA reported inflation again after several months of stability. Reports of falling tephra, 2 cm in diameter, came from a town 3 km S after explosions were witnessed during 1-3 April. On 1 April, an explosion at Minamidake summit crater produced an ash plume which rose 800 m above its crater rim; another on 3 April rose 1,700 m. Minor emissions also occurred at Minamidake on 5, 6, and 9 April. Explosions on 6 and 8 April at Showa sent ash plumes 3,500-3,700 m high and tephra 1.3 km. During the 8 April explosion at Showa, a small pyroclastic flow traveled 400 m down the E flank, the first since June 2015. A 2,200-m-high ash plume rose from Showa crater on 17 April. Minor emissions that rose 800 m were detected at Minamidake on 20 and 28 April. Two explosions occurred on 27 April at Showa, followed by additional explosions on 28, 29, and 30 April; the events generated ash plumes that rose 3,000 m. Pyroclastic flows were generated during the events of 28 and 30 April; they each flowed about 500 m, SE and E, respectively.

A large explosion at the Showa crater on 1 May sent an ash plume to 4,100 m above the crater rim (figure 57). It was the first time since 21 May 2015 that a plume rose higher than 4,000 m. At the Minamidake summit crater, ash emissions on 1 and 13 May rose 3,500 and 3,700 m, respectively, the first plumes at Minamidake over 3,000 m since October 2009. An explosion on 8 May at Showa sent an ash plume over 3,300 m above the crater rim, and tephra reached 1,300 m from the crater. Numerous ash emissions continued throughout the month, some with plumes rising to 3,500 m. The Tokyo VAAC issued 26 reports between 13 and 22 May. Activity diminished toward the end of the month, but minor inflation continued.

Figure (see Caption) Figure 57. An explosive eruption at Sakurajima's Showa Crater on 1 May 2016 sent an ash plume 4,100 m above the crater that drifted SE. It was the highest plume in the last year. Taken with the "Cattle Root" webcam, courtesy of JMA (May 2016 Monthly Sakurajima report).

Multiple ash emissions in early June 2016 produced plumes as high as 2,000 m above the Showa crater rim. An explosion on 3 June produced a pyroclastic flow that traveled 400 m SE, and tephra that was ejected 800 m from the crater. An emission at the Minamidake crater on 3 June rose 1,500m high. No further explosive activity was reported for June; only a minor emission from the Showa crater on 29 June. During the month, the Tokyo VAAC issued only six reports (during 2-3 June).

Two explosive events were recorded at Showa crater in July 2016. An explosion occurred on 2 July that produced a 1,200-m-high ash plume and sent large blocks 800 m from the crater. A substantial explosion on 26 July at Showa sent blocks 800 m from the crater, and produced an ash plume that rose 5,000 m. A minor amount of ashfall on the W and SW flanks of Sakurajima was observed, and ashfall was confirmed in a wide area from Kagoshima City (10 km W) to Hioki City (25 km NW). The Tokyo VAAC reported an ash plume drifting SW at 6.1 km altitude that day.

Minor emissions were observed at the Minamidake crater intermittently throughout August 2016, but no emissions or explosions were reported from Showa. The Tokyo VAAC reported a low-level ash plume on 22 August at 1.2 km altitude drifting 50 km SW (figure 58). This was the last VAAC report for 2016. Although there were no emissions or explosive activity reported from either crater during September-December 2016, inflation of the volcano continued, and thus the Alert Level remained at 3.

Figure (see Caption) Figure 58. An ash emission rose from Sakurajima's Minamidake crater on the morning of 22 August 2016. This was the last reported ash emission of 2016. Taken from the Tarumizu City MBC (Minaminihon Broadcasting Co., Ltd.) webcam no. 14, located about 14 km E. Courtesy of Minaminihon Broadcasting Co., Ltd. (http://www.mbc.co.jp/web-cam/).

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Hawai'i Institute of Geophysics and Planetology (HIGP), MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); NASA Earth Observatory, EOS Project Science Office, NASA Goddard Space Flight Center, Goddard, Maryland, USA (URL: http://earthobservatory.nasa.gov/); Japan Aerospace Exploration Agency (JAXA) (URL: http://global.jaxa.jp/); Associated Press (URL: http://www.ap.org/); Tom Pfeiffer, Volcano Discovery (URL: http://www.volcanodiscovery.com/ ); Naoto Yoshidome, Twitter (URL: https://twitter.com); Minaminihon Broadcasting Co., Ltd (MBC). (http://www.mbc.co.jp/web-cam/).


July 2018 (BGVN 43:07) Citation IconCite this Report

Activity resumed in March 2017 and remained relatively low through the year

Aira caldera encompasses the northern half of Kagoshima Bay in Kyushu, Japan. During the Holocene activity has been focused at Sakurajima volcano along the southern rim of the caldera, and more recent activity has occurred at the Minamidake and Showa summit craters (figure 59). Minamidake crater has been persistently active since 1955, and activity at Showa crater resumed in 2006. Sakurajima is one of Japan's most active volcanoes and frequently deposits ash over the nearby Kagoshima city. This report covers activity that occurred through 2017 and is based on reports issued by the Japan Meteorological Agency (JMA).

Figure (see Caption) Figure 59. The active Minamidake and Showa craters of Sakurajima volcano at Aira. Three incandescent vents within the craters are visible in this Sentinel-2 false color thermal image (bands 12, 11, 4) that was acquired on 13 December 2017. Courtesy of Sentinel Hub Playground.

Typical activity largely consists of Vulcanian explosions that produce ash plumes and small pyroclastic flows. Prior to a decrease in activity in August 2016, the volcano typically produced tens of explosions per month. The last recorded explosion in 2016 was a low-level ash plume on 22 August at 1.2 km altitude, reported by the Tokyo Volcanic Ash Advisory Center (VAAC). Sakurajima has remained on Activity Alert Level 3 (do not approach) on an alert level scale of 1 (little to no activity) to 5 (eruption or imminent eruption causing significant damage to residential areas).

Activity has been low since August 2016. No eruptions were observed through January and February 2017, and both seismicity and SO2 emission levels remained low.

Eruptive activity resumed on 25 March 2017 at 1803 local time, when the Minamidake crater produced an ash plume to 500 m above the crater and a pyroclastic flow travelled approximately 1,100 m to the south (figure 60). Several additional small ash emission events were noted after this event.

Figure (see Caption) Figure 60. Eruption at the Minamidake crater of Sakurajima (Aira caldera) on 25 March 2017 at 1803 local time. The ash plume reached 500 m above the crater and a pyroclastic flow traveled 1,100 m to the south. Image taken by the Kaigata surveillance camera, courtesy of JMA (March 2017 Monthly Sakurajima report).

Showa crater resumed activity at 0511 on 26 April 2017; 19 more events occurred through the month, including two larger explosive events. One explosive event produced an ash plume to 3,200 m above the crater on 28 April at 1101 local time. Two events occurred at the Minamidake crater through April.

Activity continued at the Showa crater in May, with 47 ash emission events, with nine of these being explosive events. One event on 2 May produced a 4,000-m-high plume that deposited ash on nearby communities (figure 61). Several larger explosions ejected blocks out to 500-800 m from the Showa crater. Activity continued at Minamidake crater, with ash reaching 2,500 m above the crater during an event on 5 May.

Figure (see Caption) Figure 61. Eruption of Sakurajima in the Aira caldera on 2 May 2017 at 0320 local time. The ash plume reached 4,000 m above the crater. Image taken by the Tarumi Ararazaki surveillance camera, courtesy of JMA (May 2017 Monthly Sakurajima report).

Through June, the Showa crater produced 14 events, including two explosive events. An explosion on 6 June produced an ash plume up to 3,200 m above the crater and blocks were deposited out to 800 m from the crater. One small event occurred at Minamidake. Activity was reduced in July, with seven events at Showa crater and none at Minamidake.

During August no events took place at Minamidake. However, Showa crater remained active with 98 events, including 20 that were explosive. Activity through September was similar with no activity in Minamidake crater and 170 events at Showa, including 38 explosive events.

Activity declined again from October through December. During October there were 37 events from Showa crater, with five being explosive (figure 62). One event at Minamidake crater on 31 October produced an ash plume up to 1,000 m above the crater. During November, five events occurred at Minamidake crater, and one at Showa crater that produced an ash plume to 1,300 m above the crater. In December, one event occurred at the Showa crater and Minamidake produced one small event.

Figure (see Caption) Figure 62. An explosive event is seen in this webcam image from the Sakurajima volcano Showa crater (Aira caldera) on 1 October, 2135 local time. Incandescent blocks were deposited out to 1,300 m from the crater. Image taken by the Tarumi Arasaki surveillance camera, courtesy of JMA (October 2017 Monthly Sakurajima report).

Information Contacts: Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


August 2018 (BGVN 43:08) Citation IconCite this Report

Activity increased at Minamidake and decreased at Showa crater in early 2018

Sakurajima is a persistently active volcano within the Aira caldera in Kyushu, Japan. The two currently active summit craters are Showa and Minamidake, both of which produce intermittent ash plumes and occasional pyroclastic flows. This report summarizes the activity from January through June 2018 as described in reports issued by the Japan Meteorological Agency (JMA) and Tokyo Volcanic Ash Advisory Center (VAAC).

The volcano remains on Alert Level 3 (out of five). A change in activity occurred in late 2017 to early 2018, with a reduction in activity at the Showa crater and a significant increase in activity at the Minamidake crater (table 19 and figure 63). During January through June 2018 a total of 260 explosions were recorded at Minamidake (135 of these were explosive), and four at Showa. Pyroclastic flows were produced on 1 April from Showa crater that travelled 800 m, and a flow reached 1,300 m from Minamidake crater on 16 June. Periodic incandescence was visible at the summit throughout the reporting period.

Table 19. Eruptive events and pyroclastic flows recorded at the active craters of Sakurajima volcano in Aira caldera. The number of events that were explosive in nature are in parentheses. Data courtesy of JMA (January to June 2018 monthly reports).

Month No. of ash emissions at Showa crater No. of ash emissions at Minamidake crater Pyroclastic flows
Jan 2018 1 12 (4) --
Feb 2018 0 7 (3) --
Mar 2018 0 44 (17) --
Apr 2018 3 66 (50) 800 m E from Showa.
May 2018 0 96 (48) --
Jun 2018 0 35 (13) 1,300 m SW from Minamidake.
Figure (see Caption) Figure 63. The number of monthly explosions at Minamidake (upper) and Showa (lower) craters of Sakurajima, Aira caldera. The first half of 2018 has seen a dramatic increase in activity at Minamidake, and a decrease in activity at Showa crater. Grey bars indicate eruptions and red bars specify explosive eruptions. Note that the scale on the two graphs are different. Courtesy of JMA (June 2018 monthly report).

In January 2018, one ash emission occurred at Showa crater and twelve occurred at Minamidake, with four of these classified as explosive eruptions. The largest ash plume reached 2,500 m above the crater on the 18th and two explosions ejected material out to a maximum of 700-800 m from the craters. Through February, three of seven ash emissions at Minamidake were explosive. The largest ash plume occurred on the 19th and reached 1,500 m above the crater. On the 27th, the crater ejected material out to 700 m from the crater.

Through March, 44 ash emissions occurred with 17 of these classified as explosive events. The largest ash plume was produced on the 26th and reached 3,400 m above the crater. An explosive eruption on 10 March ejected material out to 1,300 m from the crater. During April, Minamidake produced 66 ash emission; 50 of these were explosive (figure 64). Showa produced three events in total and an event on 1 April produced a pyroclastic flow that traveled 800 m to the E (figure 65).The largest ash plume was from Minamidake that reached 3,400 m above the crater.

Figure (see Caption) Figure 64. True color Sentinel-2 satellite image of an ash plume at Sakurajima, Aira caldera, at 1056 on 12 April. The Tokyo VAAC reported that the plume that reached an altitude of 2.4 km. Courtesy of Sentinel Hub Playground.
Figure (see Caption) Figure 65. Eruption of the Sakurajima Showa crater (within the Aira caldera) at 1611 on 1 April. The ash plume rose to 1,700 m above the crater and the pyroclastic flow (circled) travelled 800 m to the east. Image taken by the Kaigata webcam, courtesy of JMA (April 2018 monthly report).

Elevated activity continued at Minamidake through May, with 96 ash emissions (48 explosive), and the highest reported ash plume reaching 3,200 m above the crater on the 24th. An explosion on 5 May scattered ejecta out to 1,300 m from the crater. Activity was reduced in June with 35 ash emissions (13 explosive) from Minamidake, with an explosive event on the 16th producing an ash plume to 4,700 m above the crater and a pyroclastic flow out to 1,300 m (figure 66). This event deposited ash on nearby communities.

Figure (see Caption) Figure 66. Eruption at the Sakurajima Minamidake crater (at Aira caldera) at 1607 on 16 June. The ash plume rose to 4,700 m above the crater and the pyroclastic flow (circled) traveled 1,300 m. Image captured by the Kaigata surveillance camera, courtesy of JMA (June 2018 monthly report).

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


January 2019 (BGVN 44:01) Citation IconCite this Report

Ash plumes continue at the Minamidake crater from July through December 2018

Sakurajima is one of the most active volcanoes in Japan and is situated in the Aira caldera in southern Kyushu. It regularly produces ash plumes and scatters blocks onto the flanks during explosions. This report covers July through December 2018 and describes activity at the Minamidake crater, which has continued with the activity typically observed at Sakurajima volcano. In late 2017 the eruptive activity has migrated from being centered at the Showa crater, to being focused at the Minamidake crater. This change has continued into the later half of 2018. The following activity summarizes information issued by the Japan Meteorological Agency (JMA), the Japan Volcanic Ash Advisory Center (VAAC), and satellite data.

Activity from July through December 2018 was focused at the summit Minamidake crater with 8 to 64 ash emission events per month, with 50-60% being explosive in nature during four of the six months reported (table 20, figure 67). The maximum explosions per day was 64 on 31 August (figure 68). No pyroclastic flows were recorded during this time. Recent activity at the Showa crater has been declining and no activity was observed during the reporting period. Sakurajima has remained on Alert Level 3 on a 5-level scale during this time, reflecting the regular ash plumes and volcanic blocks that erupt out onto the slopes of the volcano during explosive events.

Table 20. Monthly summary of eruptive events recorded at Sakurajima's Minamidake crater in Aira caldera, July-December 2018. The number of events that were explosive in nature are in parentheses. No events were recorded at the Showa crater during this time. Data courtesy of JMA (July to December 2018 monthly reports).

Month Ash emissions (explosive) Max. plume height above the crater Max. ejecta distance from crater
Jul 2018 29 (16) 4.6 km 1.7 km
Aug 2018 64 (37) 2.8 km 1.3 km
Sep 2018 44 (22) 2.3 km 1.1 km
Oct 2018 8 (0) 1.6 km --
Nov 2018 14 (2) 4 km 1.7 km
Dec 2018 56 (34) 3 km 1.3 km
Figure (see Caption) Figure 67. Satellite images showing ash plumes from Sakurajima's Minamidake summit crater (Aira caldera) in August, September, and November 2018. Natural color satellite images (bands 4, 3, 2) courtesy of Sentinel Hub Playground.
Figure (see Caption) Figure 68. Explosions per day at Sakurajima's Minamidake summit crater (Aira caldera) for July through December 2018. Data courtesy of JMA.

Activity through July consisted of 29 ash emission events (16 of which were explosive) producing ash plumes up to a maximum height of 4.6 km above the crater and ballistic ejecta (blocks) out to 1.7 km from the crater, but ash plumes were more commonly 1.2 to 2.5 km high. The largest explosive event occurred on 16 July, producing an ash plume up to 4.6 km from the vent and ejecting ballistic rocks out to 1.3-1.7 km from the crater (figure 69). On 17 July, sulfur dioxide emissions were measured at 1,300 tons per day, and on 26 July emissions were measured to be 2,100 tons per day.

Figure (see Caption) Figure 69. Ash plumes erupting from the Sakurajima Minamidake crater (Aira caldera) on 16 July 2018 at 1538 (upper) and 1500 (lower) local time. The ash plumes reached 4.6 km above the crater rim and ejected rocks out to 1.3-1.7 km from the crater. Higashikorimoto webcam images courtesy of JMA (July 2018 monthly report).

During August the Minamidake crater produced 64 ash emission events (37 explosive in nature) with a maximum ash plume height of 2.8 km above the crater, and a maximum ballistic ejecta distance of 1.3 km from the crater on 31 August (figure 70). Ash plumes were more commonly up to 1 to 2.1 km above the crater. Sulfur dioxide emissions were very high on 2 August, measured as high as 3,200 tons per day, and was measured at 1,500 tons per day on 27 August.

Figure (see Caption) Figure 70. Activity at Sakurajima volcano (Aira Caldera) in August 2018. Top: A gas-and-ash plume that reached 2.8 km above the crater at 1409 on 29 August. Bottom: Scattered incandescent blocks out to 1-1.3 km from the crater on the flanks of Sakurajima after an explosion on 31 August. Higashikorimoto and Kaigata webcam images courtesy of JMA (August 2018 monthly report).

Throughout September 44 ash emission events occurred, with 22 of those being explosive in nature. The Maximum ash plume height reached 2.3 km above the crater, and the maximum ejecta landed out to 1.1 km from the crater. An explosive event on 9 September ejected material out to 700 m away from the crater and on 22 September an event scattered blocks out to 1.1 km from the crater (figure 71).

Figure (see Caption) Figure 71. Incandescent blocks on the flanks of Sakurajima volcano (Aira caldera) after an explosion on 22 September 2018 at 2025. The event scattered blocks out to 1.1 km from the Minamidake crater. Kaigata webcam image courtesy of JMA (September 2018 monthly report).

October and November were relatively quiet with regards to the number of ash emission events with only 22 events over the two months. The maximum ash plume heights reached 1.6 and 4 km, respectively. An observation flight on 22 October showed the currently inactive Showa crater restricted to minor fumarolic degassing, and steam-and-gas and dilute ash plume activity in the Minamidake crater (figure 72). An eruption on 14 November at 0043 local time produced an ash plume to over 4 km above the crater and scattered incandescent blocks out to over 1 km from the crater (figure 73). This was the first ash plume to exceed a height of 4 km since 16 July 2018. Two events occurred during 16-19 November that produced ash plumes up to 1.6 km. Sulfur dioxide measurements were 3,400 tons on 4 October, 400 tons on 17 October, 1,000 tons on 23 October, 1,100 tons on 6 November, and 1,400 tons on 20 November.

Figure (see Caption) Figure 72. Minor fumarolic degassing has occurred in Sakurajima's Showa crater (Aira caldera) and the vent has been blocked by ash and rock. The active Minamidake crater is producing a blue-white plume to 400 m above the crater and a dilute brown plume that remained within the crater. Images taken by the Japan Maritime Self-Defense Force 1st Air Group P-3C on 22 October 2018, courtesy of JMA (October 2018 monthly report).
Figure (see Caption) Figure 73. Eruption of Sakurajima (Aira caldera) on 14 November at 0043 local time ejecting incandescent blocks more than 1 km from the crater and an ash plume up to 4 km above the crater. Photos courtesy of The Asahi Shimbun.

Small ash plumes continued through December with 56 ash emission events, 34 of which were explosive in nature. The maximum ash plume height above the crater reached 3 km, and the maximum distance that ejecta traveled from the vent was 1.3 km, both during an event on 24 December (figure 74). An explosive event produced an ash plume that reached a height of 2.5 km above the crater and scattered ejecta out to 1.1 km from the crater.

Figure (see Caption) Figure 74. An explosive event at 1127 on 24 December 2018 at Sakurajima's Minamidake crater (Aira caldera). The ash plume reached 3 km above the crater rim. Higashikorimoto webcam image courtesy of JMA (December 2018 monthly report).

Intermittent incandescence was observed at the summit at nighttime throughout the entire reporting period. Areas of elevated thermal energy within the Minamidake crater were visible in cloud-free Sentinel-2 satellite images (figure 75) and elevated temperatures were detected in MIROVA on a few days.

Figure (see Caption) Figure 75. Sentinel-2 thermal satellite images showing the summit area of Sakurajima volcano, Aira caldera, in October 2018. The areas of elevated thermal activity (bright orange-red) are visible within the Minamidake crater. No thermal anomalies are visible within the Showa crater. Thermal (Urban) satellite images (bands 12, 11, 4) courtesy of Sentinel Hub Playground.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); The Asahi Shimbun (URL: http://www.asahi.com/ajw/articles/AJ201811140035.html accessed on 12 March 2018).


July 2019 (BGVN 44:07) Citation IconCite this Report

Explosions with ejecta and ash plumes continue weekly during January-June 2019

Sakurajima rises from Kagoshima Bay, which fills the Aira Caldera near the southern tip of Japan's Kyushu Island. Frequent explosive and occasional effusive activity has been ongoing for centuries. The Minamidake summit cone has been the location of persistent activity since 1955; the Showa crater on its E flank has also been intermittently active since 2006. Numerous explosions and ash-bearing emissions have been occurring each month at either Minamidake or Showa crater since the latest eruptive episode began in late March 2017. This report covers ongoing activity from January through June 2019; the Japan Meteorological Agency (JMA) provides regular reports on activity, and the Tokyo VAAC (Volcanic Ash Advisory Center) issues tens of reports each month about the frequent ash plumes.

From January to June 2019, ash plumes and explosions were usually reported multiple times each week. The quietest month was June with only five eruptive events; the most active was March with 29 (table 21). Ash plumes rose from a few hundred meters to 3,500 m above the summit during the period. Large blocks of incandescent ejecta traveled as far as 1,700 m from the Minamidake crater during explosions in February and April. All the activity originated in the Minamidake crater; the adjacent Showa crater only had a mild thermal anomaly and fumarole throughout the period. Satellite imagery identified thermal anomalies inside the Minamidake crater several times each month.

Table 21. Monthly summary of eruptive events recorded at Sakurajima's Minamidake crater in Aira caldera, January-June 2019. The number of events that were explosive in nature are in parentheses. No events were recorded at the Showa crater during this time. Data courtesy of JMA (January to June 2019 monthly reports).

Month Ash emissions (explosive) Max. plume height above crater Max. ejecta distance from crater
Jan 2019 8 (6) 2.1 km 1.1 km
Feb 2019 15 (11) 2.3 km 1.7 km
Mar 2019 29 (12) 3.5 km 1.3 km
Apr 2019 10 (5) 2.2 km 1.7 km
May 2019 15 (9) 2.9 km 1.3 km
Jun 2019 5 (2) 2.2 km 1.3 km

There were eight eruptive events reported by JMA during January 2019 at the Minamidake summit crater of Sakurajima. They occurred on 3, 6, 7, 9, 17, and 19 January (figure 76). Ash plume heights ranged from 600 to 2,100 m above the summit. The largest explosion, on 9 January, generated an ash plume that rose 2,100 m above the summit crater and drifted E. In addition, incandescent ejecta was sent 800-1,100 m from the summit. Incandescence was visible at the summit on most clear nights. During an overflight on 18 January no significant changes were noted at the crater (figure 77). Infrared thermal imaging done on 29 January indicated a weak thermal anomaly in the vicinity of the Showa crater on the SE side of Minamidake crater. The Kagoshima Regional Meteorological Observatory (KRMO) (11 km WSW) recorded ashfall there during four days of the month. Satellite imagery indicated thermal anomalies inside Minamidake on 7 and 27 January (figure 77).

Figure (see Caption) Figure 76. Incandescent ejecta and ash emissions characterized activity from Sakurajima volcano at Aira during January 2019. Left: A webcam image showed incandescent ejecta on the flanks on 9 January 2019, courtesy of JMA (Explanation of volcanic activity in Sakurajima, January 2019). Right: An ash plume rose hundreds of meters above the summit, likely also on 9 January, posted on 10 January 2019, courtesy of Mike Day.
Figure (see Caption) Figure 77. The summit of Sakurajima consists of the larger Minamidake crater and the smaller Showa crater on the E flank. Left: The Minamidake crater at the summit of Sakurajima volcano at Aira on 18 January 2019 seen in an overflight courtesy of JMA (Explanation of volcanic activity in Sakurajima, March 2019). Right: Two areas of thermal anomaly were visible in Sentinel-2 satellite imagery on 27 January 2019. "Geology" rendering (bands 12, 4, and 2) courtesy of Sentinel Hub Playground.

Activity increased during February 2019, with 15 eruptive events reported on days 1, 3, 7, 8, 10, 13, 14, 17, 22, 24, and 27. Ash plume heights ranged from 600-2,300 m above the summit, and ejecta was reported 300 to 1,700 m from the crater in various events (figure 78). KRMO reported two days of ashfall during February. Satellite imagery identified thermal anomalies at the crater on 6 and 26 February, and ash plumes on 21 and 26 February (figure 79).

Figure (see Caption) Figure 78. An explosion from Sakurajima at Aira on 7 February 2019 sent ejecta up to 1,700 m from the Minamidake summit crater. Courtesy of JMA (Explanation of volcanic activity in Sakurajima, February 2019).
Figure (see Caption) Figure 79. Thermal anomalies and ash emissions were captured in Sentinel-2 satellite imagery on 6, 21, and 26 February 2019 originating from Sakurajima volcano at Aira. Top: Thermal anomalies within the summit crater were visible underneath steam and ash plumes on 6 and 26 February (closeup of bottom right photo). Bottom: Ash emissions on 21 and 26 February drifted SE from the volcano. "Geology" rendering (bands 12, 4, and 2) courtesy of Sentinel Hub Playground.

The number of eruptive events continued to increase during March 2019; there were 29 events reported on numerous days (figures 80 and 81). An explosion on 14 March produced an ash plume that rose 3,500 m above the summit and drifted E. It also produced ejecta that landed 800-1,100 m from the crater. During an overflight on 26 March a fumarole was the only activity in Showa crater. KRMO reported 14 days of ashfall during the month. Satellite imagery identified an ash plume on 13 March and a thermal anomaly on 18 March (figure 82).

Figure (see Caption) Figure 80. A large ash emission from Sakurajima volcano at Aira was photographed by a tourist on the W flank and posted on 1 March 2019. Courtesy of Kratü.
Figure (see Caption) Figure 81. An ash plume from Sakurajima volcano at Aira on 18 March 2019 produced enough ashfall to disrupt the trains in the nearby city of Kagoshima according to the photographer. Image taken from about 20 km away. Courtesy of Tim Board.
Figure (see Caption) Figure 82. An ash plume drifted SE from the summit of Sakurajima volcano at Aira on 13 March (left) and a thermal anomaly was visible inside the Minamidake crater on 18 March 2019 (right). "Geology" rendering (bands 12, 4, and 2) courtesy of Sentinel Hub Playground.

A decline in activity to only ten eruptive events on days 7, 13, 17, 22, and 25 was reported by JMA for April 2019. An explosion on 7 April sent ejecta up to 1,700 m from the crater. Another explosion on 13 April produced an ash plume that rose 2,200 m above the summit. Most of the eruptive events at Sakurajima last for less than 30 minutes; on 22 April two events lasted for almost an hour each producing ash plumes that rose 1,400 m above the summit. Ashfall at KRMO was reported during seven days in April. Two distinct thermal anomalies were visible inside the Minamidake crater on both 12 and 27 April (figure 83).

Figure (see Caption) Figure 83. Two thermal anomalies were present inside Minamidake crater at the summit of Sakurajima volcano at Aira on 12 (left) and 27 (right) April 2019. "Geology" rendering (bands 12, 4, and 2) courtesy of Sentinel Hub Playground.

There were 15 eruptive events during May 2019. An event that lasted for two hours on 12 May produced an ash plume that rose 2,900 m from the summit and drifted NE (figure 84). The Meteorological Observatory reported 14 days with ashfall during the month. Two thermal anomalies were present in satellite imagery in the Minamidake crater on both 17 and 22 May.

Figure (see Caption) Figure 84. An ash plume rose 2,900 m above the summit of Sakurajima at Aira on 12 May 2019 (left); incandescent ejecta went 1,300 m from the summit crater on 13 May. Courtesy of JMA (Explanation of volcanic activity in Sakurajima, May 2019).

During June 2019 five eruptive events were reported, on 11, 13, and 24 June; the event on 11 June lasted for almost two hours, sent ash 2,200 m above the summit, and produced ejecta that landed up to 1,100 m from the crater (figure 85). Five days of ashfall were reported by KRMO.

Figure (see Caption) Figure 85. A large ash plume on 11 June 2019 rose 2,200 m above the summit of Sakurajima volcano at Aira. Courtesy of Aone Wakatsuki.

Information Contacts: Japan Meteorological Agency (JMA), Otemachi, 1-3-4, Chiyoda-ku Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); Mike Day, Minnesota, Twitter (URL: https://twitter.com/MikeDaySMM, photo at https://twitter.com/MikeDaySMM/status/1083489400451989505/photo/1); Kratü, Twitter (URL: https://twitter.com/TalesOfKratue, photo at https://twitter.com/TalesOfKratue/status/1101469595414589441/photo/1); Tim Board, Japan, Twitter (URL: https://twitter.com/Hawkworld_, photo at https://twitter.com/Hawkworld_/status/1107789108754038789); Aone Wakatsuke, Twitter (URL: https://twitter.com/AoneWakatsuki, photo at https://twitter.com/AoneWakatsuki/status/1138420031258210305/photo/3).


January 2020 (BGVN 45:01) Citation IconCite this Report

Ongoing explosions with ejecta and ash plumes, along with summit incandescence, during July-December 2019

Sakurajima is a highly active stratovolcano situated in the Aira caldera in southern Kyushu, Japan. Common volcanism for this recent eruptive episode since March 2017 includes frequent explosions, ash plumes, and scattered ejecta. Much of this activity has been focused in the Minamidake crater since 1955; the Showa crater on the E flank has had intermittent activity since 2006. This report updates activity during July through December 2019 with the primary source information from monthly reports by the Japan Meteorological Agency (JMA) and various satellite data.

During July to December 2019, explosive eruptions and ash plumes were reported multiple times per week by JMA. November was the most active, with 137 eruptive events, seven of which were explosive while August was the least active with no eruptive events recorded (table 22). Ash plumes rose between 800 m to 5.5 km above the crater rim during this reporting period. Large blocks of incandescent ejecta traveled as far as 1.7 km from the Minamidake crater during explosions in September through December. The Kagoshima Regional Meteorological Observatory (11 km WSW) reported monthly amounts of ashfall during each month, with a high of 143 g/m2 during October. Occasionally at night throughout this reporting period, crater incandescence was observed with a highly sensitive surveillance camera. All explosive activity originated from the Minamidake crater; the adjacent Showa crater produced mild thermal anomalies and gas-and-steam plumes.

Table 22. Monthly summary of eruptive events recorded at Sakurajima's Minamidake crater in the Aira caldera, July through December 2019. The number of events that were explosive in nature are in parentheses. No events were recorded at the Showa crater during this time. Ashfall is measured at the Kagoshima Local Meteorological Observatory (KLMO), 10 km W of Showa crater. Data courtesy of JMA (July to December 2019 monthly reports).

Month Ash emissions (explosive) Max plume height above crater Max ejecta distance from crater Total amount of ashfall (g/m2)
Jul 2019 9 (5) 3.8 km 1.1 km --
Aug 2019 -- 800 m -- 2
Sep 2019 32 (11) 3.4 km 1.7 km 115
Oct 2019 62 (41) 3.0 km 1.7 km 143
Nov 2019 137 (77) 5.5 km 1.7 km 69
Dec 2019 71 (49) 3.3 km 1.7 km 54

An explosion that occurred at 1044 on 4 July 2019 produced an ash plume that rose up to 3.2 km above the Minamidake crater rim and ejected material 1.1 km from the vent. Field surveys conducted on 17 and 23 July measured SO2 emissions that were 1,200-1,800 tons/day. Additional explosions between 19-22 July generated smaller plumes that rose to 1.5 km above the crater and ejected material 1.1 km away. On 28 July explosions at 1725 and 1754 produced ash plumes 3.5-3.8 km above the crater rim, which resulted in ashfall in areas N and E of Sakurajima (figure 86), including Kirishima City (20 km NE), Kagoshima Prefecture (30 km SE), Yusui Town (40 km N), and parts of the Kumamoto Prefecture (140 km NE).

Figure (see Caption) Figure 86. Photo of the Sakurajima explosion at 1725 on 28 July 2019 resulting in an ash plume rising 3.8 km above the crater (left). An on-site field survey on 29 July observed ashfall on roads and vegetation on the N side of the island (right). Photo by Moto Higashi-gun (left), courtesy of JMA (July 2019 report).

The month of August 2019 showed the least activity and consisted of mainly small eruptive events occurring up to 800 m above the crater; summit incandescence was observed with a highly sensitive surveillance camera. SO2 emissions were measured on 8 and 13 August with 1,000-2,000 tons/day, which was slightly greater than the previous month. An extensometer at the Arimura Observation Tunnel and an inclinometer at the Amida River recorded slight inflation on 29 August, but continuous GNSS (Global Navigation Satellite System) observations showed no significant changes.

In September 2019 there were 32 eruptive events recorded, of which 11 were explosions, more than the previous two months. Seismicity also increased during this month. An extensometer and inclinometer recorded inflation at the Minamidake crater on 9 September, which stopped after the eruptive events. On 16 September, an eruption at 0746 produced an ash plume that rose 2.8 km above the crater rim and drifted SW; a series of eruptive events followed from 0830-1110 (figure 87). Explosions on 18 and 20 September produced ash plumes that rose 3.4 km above the crater rim and ejecting material as far as 1.7 km from the summit crater on the 18th and 700 m on the 20th. Field surveys measured an increased amount of SO2 emissions ranging from 1,100 to 2,300 tons/day during September.

Figure (see Caption) Figure 87. Webcam image of an ash plume rising 2.8 km from the Minamidake crater at Sakurajima on 16 September 2019. Courtesy of Weathernews Inc.

Seismicity, SO2 emissions, and the number of eruptions continued to increase in October 2019, 41 of which were explosive. Field surveys conducted on 1, 11, and 15 October reported that SO2 emissions were 2,000-2,800 tons/day. An explosion at 0050 on 12 October produced an ash plume that traveled 1.7 km from the Minamidake crater. Explosions between 16 and 19 October produced an ash plume that rose up to 3 km above the crater rim (figure 88). The Japan Maritime Self-Defense Force 1st Air group observed gas-and-steam plumes rising from both the Minamidake and Showa craters on 25 October. The inflation reported from 16 September began to slow in late October.

Figure (see Caption) Figure 88. Photos taken from the E side of Sakurajima showing gas-and-steam emissions with some amount of ash rising from the volcano on 16 October 2019 after an explosion around 1200 that day (top). At night, summit incandescence is observed (bottom). Courtesy of Bradley Pitcher, Vanderbilt University.

November 2019 was the most active month during this reporting period with increased seismicity, SO2 emissions, and 137 eruptive events, 77 of which were explosive. GNSS observations indicated that inflation began to slow during this month. On 8 November, an explosion at 1724 produced an ash plume up to a maximum of 5.5 km above the crater rim and drifted E. This explosion ejected large blocks as far as 500-800 m away from the crater (figure 89). The last time plumes rose above 5 km from the vents occurred on 26 July 2016 at the Showa crater and on 7 October 2000 at the Minamidake crater. Field surveys on 8, 21, and 29 November measured increased SO2 emissions ranging from 2,600 to 3,600 tons/day. Eruptions between 13-19 November produced ash plumes that rose up to 3.6 km above the crater and ejected large blocks up 1.7 km away. An onsite survey on 29 November used infrared thermal imaging equipment to observe incandescence and geothermal areas near the Showa crater and the SE flank of Minamidake (figure 90).

Figure (see Caption) Figure 89. Photos of an ash plume rising 5.5 km above Sakurajima on 8 November 2019 and drifting E. Photo by Moto Higashi-gun (top left), courtesy of JMA (November 2019 report) and the Geoscientific Network of Chile.
Figure (see Caption) Figure 90. Webcam image of nighttime incandescence and gas-and-steam emissions with some amount of ash at Sakurajima on 29 November 2019. Courtesy of JMA (November 2019 report).

Volcanism, which included seismicity, SO2 emissions, and eruptive events, decreased during December 2019. Explosions during 4-10 December produced ash plumes that rose up to 2.6 km above the crater rim and ejected material up to 1.7 km away. Field surveys conducted on 6, 16, and 23 December measured SO2 emissions around 1,000-3,000 tons/day. On 24 December, an explosion produced an ash plume that rose to 3.3 km above the crater rim, this high for this month.

Sentinel-2 natural color satellite imagery showed dense ash plumes in late August 2019, early November, and through December (figure 91). These plumes drifted in different directions and rose to a maximum 5.5 km above the crater rim on 8 November.

Figure (see Caption) Figure 91. Natural color Sentinel-2 satellite images of Sakurajima within the Aira caldera from late August through December 2019 showed dense ash plumes rising from the Minamidake crater. Courtesy of Sentinel Hub Playground.

MIROVA (Middle InfraRed Observation of Volcanic Activity) analysis of MODIS satellite data showed intermittent thermal anomalies beginning in mid-August to early September 2019 after a nearly two-month hiatus (figure 92). Activity increased by early November and continued through December. Three Sentinel-2 thermal satellite images between late July and early October showed distinct thermal hotspots within the Minamidake crater, in addition to faint gas-and-steam emissions in July and September (figure 93).

Figure (see Caption) Figure 92. Thermal anomalies at Sakurajima during January-December 2019 as recorded by the MIROVA system (Log Radiative Power) started up in mid-August to early September after a two-month break and continued through December. Courtesy of MIROVA.
Figure (see Caption) Figure 93. Sentinel-2 thermal satellite images showing small thermal anomalies and gas-and-steam emissions (left and middle) at Sakurajima within the Minamidake crater between late July and early October 2019. All images with "Atmospheric penetration" (bands 12, 11, 8A) rendering; courtesy of Sentinel Hub Playground.

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); Weathernews Inc. (Twitter: @wni_jp, https://twitter.com/wni_jp, URL: https://weathernews.jp/s/topics/201608/210085/, photo posted at https://twitter.com/wni_jp/status/1173382407216652289); Bradley Pitcher, Vanderbilt University, Nashville. TN, USA (URL: https://bradpitcher.weebly.com/, Twitter: @TieDyeSciGuy, photo posted at https://twitter.com/TieDyeSciGuy/status/1185191225101471744); Geoscientific Network of Chile (Twitter: @RedGeoChile, https://twitter.com/RedGeoChile, Facebook: https://www.facebook.com/RedGeoChile/, photo posted at https://twitter.com/RedGeoChile/status/1192921768186515456).


July 2020 (BGVN 45:07) Citation IconCite this Report

Near-daily explosions with ash plumes continue, large block ejected 3 km from Minamidake crater on 4 June 2020

Sakurajima rises from Kagoshima Bay, which fills the Aira Caldera near the southern tip of Japan's Kyushu Island. Frequent explosive and occasional effusive activity has been ongoing for centuries. The Minamidake summit cone has been the location of persistent activity since 1955; the adjacent Showa crater on its E flank has also been intermittently active since 2006. Numerous explosions and ash-bearing emissions have been occurring each month at either Minamidake or Showa crater since the latest eruptive episode began in late March 2017. This report covers ongoing activity at Minamidake from January through June 2020; the Japan Meteorological Agency (JMA) provides regular reports on activity, and the Tokyo VAAC (Volcanic Ash Advisory Center) issues tens of reports each month about the frequent ash plumes.

Activity continued during January-June 2020 at Minamidake crater with tens of explosions each month. The Tokyo VAAC issued multiple daily reports of ash emissions during January and February. Less activity occurred during the first half of March but picked up again with multiple daily reports from mid-March through mid-April. Emissions were more intermittent but continued through early June, when activity decreased significantly. JMA reported explosions with ash plumes rising 2.5-4.2 km above the summit, and ejecta traveling generally up to 1,700 m from the crater, although a big explosion in early June send a large block of tephra 3 km from the crater (table 23). Thermal anomalies were visible in satellite imagery on a few days most months and were persistent in the MIROVA thermal anomaly data from November 2019 through early June 2020 (figure 94). Incandescence was often visible at night in the webcams through early June; the Showa crater remained quiet throughout the period.

Table 23. Monthly summary of eruptive events recorded at Sakurajima's Minamidake crater within the Aira Caldera, January through June 2020. The number of events that were explosive in nature are in parentheses. No events were recorded at the Showa crater during this time. Ashfall is measured at the Kagoshima Local Meteorological Observatory (KLMO), 10 km W of Showa crater. Data courtesy of JMA (January to June 2020 monthly reports).

Month Ash emissions (explosive) Max plume height above crater Max ejecta distance from crater Total amount of ashfall (g/m2) Total ashfall previous month
Jan 2020 104 (65) 2.5 km 1,700 m 75 (12 days) 280,000 tons
Feb 2020 129 (67) 2.6 km 1,800 m 21 (14 days) 230,000 tons
Mar 2020 26 (10) 3.0 km 1,700 m 3 (8 days) 360,000 tons
Apr 2020 51 (14) 3.8 km 1,700 m less than 0.5 (2 days) 160,000 tons
May 2020 51 (24) 4.2 km 1,300 m 19 (8 days) 280,000 tons
Jun 2020 28 (16) 3.7 km 3,000 m 71 (9 days) 150,000 tons
Figure (see Caption) Figure 94. Persistent thermal anomalies were recorded in the MIROVA thermal energy data for the period from 2 July 2019 through June 2020. Thermal activity increased in October 2019 and remained steady through May 2020, decreasing abruptly at the beginning of June. Courtesy of MIROVA.

Explosions continued at Minamidake crater during January 2020 with 65 ash plumes reported. The highest ash plume rose 2.5 km above the crater on 30 January, and incandescent ejecta reached up to 1,700 m from the Minamidake crater on 22 and 29 January (figure 95). Slight inflation of the volcano since September 2019 continued to be measured with inclinometers and extensometers on Sakurajima Island. Field surveys conducted on 15, 20, and 31 January measured the amount of sulfur dioxide gas released as very high at 3,400-4,700 tons per day, as compared with 1,000-3,000 tons in December 2019.

Figure (see Caption) Figure 95. An explosion at the Minamidake summit crater of Aira’s Sakurajima volcano on 29 January 2020 produced an ash plume that rose 2.5 km above the crater rim and drifted SE (left). On 22 January incandescent ejecta reached 1,700 m from the summit during explosive events. Courtesy of JMA (Sakurajima Volcanic Activity Commentary, January 2020).

About the same number of explosions produced ash plumes during February 2020 (67) as in January (65) (figure 96). On 10 February a large block was ejected 1,800 m from the crater, the first to reach that far since 5 February 2016. The tallest plume, on 26 February rose 2.6 km above the crater. Sentinel-2 satellite imagery indicated two distinct thermal anomalies within the Minamidake crater on both 1 and 6 February (figure 97). Activity diminished during March 2020 with only 10 explosions out of 26 eruptive events. On 21 March a large bomb reached 1,700 m from the crater. The tallest ash plume rose 3 km above the crater on 17 March. Scientists noted during an overflight on 16 March that a small steam plume was rising from the inner wall on the south side of the Showa crater; a larger steam plume rose to 300 m above the Minamidake crater and drifted S (figure 98). Sulfur dioxide emissions were similar in February (1,900 to 3,100 tons) and March (1,300 to 3,400 tons per day).

Figure (see Caption) Figure 96. An ash plume rose from the Minamidake crater at the summit of Aira’s Sakurajima volcano on 6 February 2020 at 1752 local time, as seen looking S from the Kitadake crater. Courtesy of JMA (Sakurajima Volcanic Activity Commentary, February 2020).
Figure (see Caption) Figure 97. Sentinel-2 satellite imagery revealed two distinct thermal anomalies within the Minamidake crater at Aira’s Sakurajima volcano on 1 and 6 February 2020. Images use Atmospheric penetration rendering (bands 12, 11, 8A). Courtesy of Sentinel Hub playground.
Figure (see Caption) Figure 98. During an overflight of Aira’s Sakurajima volcano on 16 March 2020, JMA captured this view to the SW of the Kitadake crater on the right, the steam-covered Minamidake crater in the center, and the smaller Showa crater on the left adjacent to Minamidake. Courtesy of JMA and the Maritime Self-Defense Force 1st Air Group P-1 (Sakurajima Volcanic Activity Commentary, March 2020).

During April 2020, ejecta again reached as far as 1,700 m from the crater; 14 explosions were identified from the 51 reported eruptive events, an increase from March. The tallest plume, on 4 April, rose 3.8 km above the crater (figure 99). The same number of eruptive events occurred during May 2020, but 24 were explosive in nature. A large plume on 9 May rose to 4.2 km above the rim of Minamidake crater, the tallest of the period (figure 100). On 20 May, incandescent ejecta reached 1,300 m from the summit. Sulfur dioxide emissions during April (1,700-2,100 tons per day) and May (1,200-2,700 tons per day) were slightly lower than previous months.

Figure (see Caption) Figure 99. A large ash plume at Aira’s Sakurajima volcano rose from Minamidake crater at 1621 on 4 April 2020. The plume rose to 3.8 km above the crater and drifted SE. Courtesy of JMA (Sakurajima Volcanic Activity Commentary, April 2020).
Figure (see Caption) Figure 100. Activity continued at Aira’s Sakurajima volcano during May 2020. A large plume rose to 4.2 km above the summit and drifted N in the early morning of 9 May (left). The Kaigata webcam located at the Osumi River National Highway Office captured abundant incandescent ejecta reaching 1,300 m from the crater during the evening of 20 May. Courtesy of JMA (Sakurajima Volcanic Activity Commentary, May 2020).

A major explosion on 4 June 2020 produced 137 Pa of air vibration at the Seto 2 observation point on Sakurajima Island. It was the first time that air vibrations exceeding 100 Pa have been observed at the Seto 2 station since the 21 May 2015 explosion at the Showa crater. The ash plume associated with the explosion rose 1.5 km above the crater rim. During an 8 June field survey conducted in Higashisakurajima-cho, Kagoshima City, a large impact crater believed to be associated with this explosion was located near the coast 3 km SSW from Minamidake. The crater formed by the ejected block was about 6 m in diameter and 2 m deep (figure 101); fragments found nearby were 10-20 cm in diameter (figure 102). A nearby roof was also damaged by the blocks. Smaller bombs were found in Kurokami-cho, Kagoshima City, around 4- 5 km E of Minamidake on 5 June; the largest fragment was 5 cm in diameter. Multiple ash plumes rose to 3 km or more above the summit during the first ten days of June; explosions on 4 and 5 June reached 3.7 km above the crater (figure 103). Larger than normal inflation and deflation before and after the explosions was recorded during early June in the inclinometers and extensometers located on the island. Incandescence at the summit was observed at night through the first half of June. The Tokyo VAAC issued multiple daily ash advisories during 1-10 June after which activity declined abruptly. Two brief explosions on 23 June and one on 28 June were the only two additional ash explosions reported in June.

Figure (see Caption) Figure 101. A large crater measuring 6 m wide and 2 m deep was discovered 3 km from the Minamidake crater in Higashisakurajima, part of Kagoshima City, on 8 June 2020. It was believed to be from the impact of a large block ejected during the 4 June explosion at Aira’s Sakurajima volcano. Photo courtesy of Kagoshima City and JMA (Sakurajima Volcanic Activity Commentary, June 2020).
Figure (see Caption) Figure 102. Fragments 10-30 cm in diameter from a large bomb that traveled 3 km from Minamidake crater on Sakurajima were found a few days after the 4 June 2020 explosion at Aira. Courtesy of JMA, photo courtesy of Kagoshima City (Sakurajima Volcanic Activity Commentary, June 2020).
Figure (see Caption) Figure 103. An ash plume rose 3.7 km above the Minamidake crater at Aira’s Sakurajima volcano on 5 June 2020 and was recorded in Sentinel-2 satellite imagery. Image uses Atmospheric penetration rendering (bands 12, 11, 8A). Courtesy of Sentinel Hub playground.

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


January 2021 (BGVN 46:01) Citation IconCite this Report

Intermittent explosions continue during July through December 2020

Sakurajima is the active volcano within the Aira Caldera in Kyushu, Japan. With several craters historically active, the current activity is concentrated in the Minamidake summit crater. Activity usually consists of small explosions producing ashfall and ballistic ejecta, with occasional pyroclastic flows and lahars. The current eruption has been ongoing since 25 March 2017, but activity has been frequent over the past few hundred years. This bulletin summarizes activity that occurred during July through December 2020 and is largely based on reports by the Japan Meteorological Agency (JMA) and satellite data. The Alert Level remains at 3 on a 5-level scale. There was no activity at the Showa crater in 2020.

The number of recorded explosive and ash eruptions for 2020 at the Minamidake crater were 221 and 432, respectively (228 and 393 the previous year). Activity declined in July and remained low through the end of December. There was ash reported on 79 days of the year, most frequently in January, and only 26 of those days during August-December (table 24 and figure 104). The largest ash plumes during this time reached 5 km at 0538 on 9 August, 3 km at 1959 on 17 December, and 3.5 km at 1614 on 29 December. The decline in events was reflected in thermal data, with a decline in energy detected during June through October (figure 105). Recorded SO2 was generally high in the first half of the year then began to decrease from April to around 1,000 tons/day until around late May. Emissions increased after August and were extremely high in October. There were no notable changes in the geothermal areas around the craters.

Table 24. Number of monthly total eruptions, explosive eruptions, days of ashfall, and ashfall amounts from Sakurajima's Minamidake crater at Aira during 2020. Note that smaller events that did not reach the threshold of explosions or eruptions also occurred. Ashfall was measured at Kagoshima Local Meteorological Observatory; ash weights are rounded down to the nearest 0.5 g/m2 and zero values indicate that less than this amount was recorded. Data courtesy of JMA.

MonthExplosive EruptionsAsh EruptionsDays of AshfallAshfall Amount (g/m2)
Jan 2020 65 104 12 75
Feb 2020 67 129 14 21
Mar 2020 10 26 8 3
Apr 2020 14 51 2 0
May 2020 24 51 8 19
Jun 2020 16 28 9 71
Jul 2020 0 0 0 0
Aug 2020 1 1 1 0
Sep 2020 0 7 4 2
Oct 2020 0 2 6 2
Nov 2020 6 8 11 5
Dec 2020 18 25 4 14
Total 2020 221 432 79 212
Figure (see Caption) Figure 104. The total calculated observed ash erupted from Aira's Sakurajima volcano. Top: Annual values from January 1980 to November 2020. Bottom: the monthly values during January 2009 through November 2020. Courtesy of JMA (January 2021 Sakurajima monthly report).
Figure (see Caption) Figure 105. Thermal data detected at Aira's Sakurajima volcano during February through December 2020 by the MIROVA thermal detection system that uses MODIS satellite middle infrared data. There was a decline in activity during June-September, with energy emitted in November-December remaining lower than earlier in the year. Courtesy of MIROVA.

During July "very small" explosions were observed on the 1st, 2nd, and 8th, with the last explosion producing a plume up to 600 m above the crater. These events didn't generate enough of an ash plume to be counted as either a quiet or explosive eruption, leaving no eruptions reported during July. No incandescence was observed at the crater since 3 June. Field surveys on 2, 13, and 21 July detected 600 to 1,300 tons of SO2 per day.

An explosion occurred at 0538 on 9 August, producing an ash plume to 5 km above the crater, dispersing NE (figure 106). This was the largest explosion observed through the Sakurajima surveillance camera since 8 November 2019. Ashfall was reported in Kagoshima City, Aira City, Kirishima City, Yusui Town, and parts of Miyazaki and Kumamoto Prefectures. Ashfall measured to be 300 g/m2 in Shirahama on Sakurajima island (figure 106). No ballistic ejecta were observed due to clouds at the summit, but very small explosions were occasionally observed afterwards.

Figure (see Caption) Figure 106. An explosion at Aira's Sakurajima volcano at 0538 on 9 August 2020 (top, taken from the Ushine surveillance camera in Kagoshima) produced ashfall in Shirahama on Sakurajima (bottom). The plume contains a white steam-rich portion on the left, and a darker relatively ash-rich portion on the right. Images courtesy of JMA (Sakurajima August 2020 monthly report).

A small lake or pond in the eastern Minamidake crater was first observed in PlanetScope satellite imagery on 1 August (through light cloud cover) and intermittently observed when the summit was clear through to the 22nd (figure 107). The summit is obscured by cloud cover in many images before this date. An observation flight on 14 August confirmed weak gas emission from the inner southern wall of the Showa crater, and a 200-m-high gas plume rose from the Minamidake crater, dispersing SE (figure 108). Thermal imaging showed elevated temperatures within the crater. SO2 measurements were conducted during field surveys on the 3rd, 13th, 24th and 31st, with amounts similar to July at 600 to 1,400 tons per day.

Figure (see Caption) Figure 107. A crater lake is visible in the eastern part of the Minamidake summit crater at Aira's Sakurajima volcano on 5, 18, and 22 August 2020. Four-band PlanetScope satellite images courtesy of Planet Labs.
Figure (see Caption) Figure 108. Gas emissions from the Minamidake and Showa craters at Sakurajima in the Aira caldera on 14 August 2020. Photos taken from the from Kagoshima Prefecture disaster prevention helicopter at 1510-1513. Courtesy of JMA (Sakurajima August monthly report).

Activity continued at Minamidake crater throughout September with seven observed eruptions sending plumes up to 1.7 km above the crater, and additional smaller events (figure 109). An ash plume reached 1 km at 0810 on the 15th. Ashfall was reported on four days through the month with a total of 2 g/m2 measured. Incandescence was observed in nighttime surveillance cameras from the 9-10th for the first time since 2 June, then continued through the month. There was an increase in detected SO2, with measurements on the 11th and 25th ranging from 1,300 to 2,000 tons per day.

Figure (see Caption) Figure 109. Examples of activity at Aira's Sakurajima volcano on 4, 10, and 14 September 2020. The images show an ash plume reaching 1.7 km above the crater (top left), a gas-and-steam plume (bottom left), and incandescence at night visible in a gas-and steam plume (right). Images courtesy of JMA (September 2020 Sakurajima monthly report).

During October two eruptions and occasional smaller events occurred at the Minamidake crater and there were six days where ashfall occurred at the Kagoshima Local Meteorology Observatory (including remobilized ash). An ash plume rose to 1.7 km above the crater at 1635 on the 3rd and 1 km on the 30th. Incandescence was observed at night through the month (figure 110). Gas surveys on the 20th, 21st, 23rd, and 26th recorded 2,200-6,600 tons of SO2 per day, which are high to very high levels and a large increase compared to previous months. An observation flight on the 13th confirmed lava in the bottom of the Minamidake crater (figure 111). Gas emissions were rising to 300 m above the Minamidake crater, but no emissions were observed at the Showa crater (figure 112).

Figure (see Caption) Figure 110. Gas emissions and incandescence seen above the Sakurajima Minamidake crater at Aira on 10 and 23 October 2020. Courtesy of JMA (Sakurajima October 2020 monthly report).
Figure (see Caption) Figure 111. Lava was observed on the floor of the Minamidake summit crater at Aira's Sakurajima volcano on 13 October 2020, indicated by the yellow dashed line. Courtesy of JMA (Sakurajima October 2020 monthly report).
Figure (see Caption) Figure 112. An observation flight on 13 October 2020 noted gas emissions up to 300 m above the Minamidake crater at Sakurajima, but no emissions from the Showa crater. Courtesy of JMA (Sakurajima October 2020 monthly report).

Eight ash eruptions and six explosive eruptions occurred during November as well as additional very small events. At 1551 on the 3rd an ash plume reached 1.8 km above the crater and an event at 1335 on the 10th produced large ballistic ejecta out to 600-900 m from the crater (figure 113). Ashfall was reported on 11 days this month (including remobilized ash). Incandescence was observed at night and elevated temperatures in the Minamidake crater were detected by satellites (figure 114). Detected SO2 was lower this month, with amounts ranging between 1,300 and 2,200 on the 9th, 18th and 24th.

Figure (see Caption) Figure 113. Ash plumes at Aira's Sakurajima volcano rise from the Minamidake crater in November 2020. Left: an ash plume rose to 1.8 km above the crater at 1551 on the 3rd and drifted SE. on 3 (left) and 10 (right) November 2020. Right: An explosion at 1335 on the 10th produced an ash plume to 1.6 km above the crater and ballistic ejecta out to 600-900 m, with one projectile indicated by the red arrow. Courtesy of JMA (Sakurajima November 2020 monthly report).
Figure (see Caption) Figure 114. An ash plume drifts SE from the Minamidake crater at Aira's Sakurajima volcano on 8 November 2020. This thermal image also shows elevated temperatures in the crater. Sentinel-2 False color (urban) satellite image (bands 12, 11, 4) courtesy of Sentinel Hub Playground.

During December there were 25 ash eruptions and 18 explosive eruptions recorded, with large ballistic ejecta reaching 1.3-1.7 km from the crater (figure 115). An explosion on the 2nd sent an ash plume up to 1 km above the crater and ballistic ejecta out to 1-1.3 km, and an event at 0404 on the 12th produced incandescent ballistic ejecta reached out to 1.3-1.7 km from the crater. At 1959 on 17 December an explosion generated an ash plume up to 3 km above the crater and ejecta out to 1.3-1.7 km. A photograph that day showed an ash plume with volcanic lightning and incandescent ejecta impacting around the crater (figure 116). On the 18th an ash plume reached 1.8 km and ejecta impacted out to 1-1.3 km. An event at 1614 on the 29th produced an ash plume reaching 3.5 km above the crater. Elevated temperatures within the Minamidake crater and plumes were observed intermittently in satellite data through the month (figure 117). This month there were four days where ashfall was recorded with a total of 14 g/m2. Incandescence continued to be observed at night through the month. High levels of gas emission continued, with field surveys on 2nd, 7th, 16th and 21st recording values ranging from 1,500 to 2,900 tons per day at the Observatory located 11 km SW.

Figure (see Caption) Figure 115. Explosions at Aira's Sakurajima volcano from the Minamidake summit crater in December 2020. Top: An explosion recorded at 0404 on the 12th produced incandescent ballistic ejecta out to 1.3-1.7 km from the crater, with an example indicated in the red circle. Bottom: An explosion at 1614 on the 29th produced an ash plume up to 3.5 km above the crater, and ballistic ejecta out to 1.3-1.7 km. Courtesy of JMA (top, from Sakurajima December 2020 monthly report) and Volcano Time Lapse (bottom).
Figure (see Caption) Figure 116. An explosion from Sakurajima's Minamidake crater at Aira produced an ash plume with volcanic lightning on 17 December 2020. Photograph taken from Tarumizu city, courtesy of Kyodo/via Reuters.
Figure (see Caption) Figure 117. Activity at Aira's Sakurajima volcano during December 2020. Top: Sentinel-2 thermal satellite image showing a diffuse gas-and-steam plume dispersing to the SE with elevated temperatures within the Minamidake summit crater on the 22nd. PlanetScope satellite image showing an ash plume dispersing between the N and E on the 26th. Sentinel-2 False color (urban) satellite image (bands 12, 11, 4) courtesy of Sentinel Hub Playground. PlanetScope satellite image courtesy of Planet Labs.

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Tokyo Volcanic Ash Advisory Center (VAAC), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://ds.data.jma.go.jp/svd/vaac/data/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground); Planet Labs, Inc. (URL: https://www.planet.com/); Kyodo/via REUTERS, "Photos of the Week" (URL: https://www.reuters.com/news/picture/photos-of-the-week-idUSRTX8HYLR); Volcano Time-Lapse, YouTube (URL: https://www.youtube.com/watch?v=jTgd152oGVo).


August 2021 (BGVN 46:08) Citation IconCite this Report

Intermittent explosions, ash plumes, ashfall, and incandescent ejecta through June 2021

The Aira caldera is located in the northern half of Kagoshima Bay in Kyushu, Japan and contains the active post-caldera Sakurajima volcano. Though several craters have been historically active, current activity is focused in the Minamidake summit crater, which has recently been erupting since March 2017. Activity is characterized by intermittent explosions, ash plumes and resulting ashfall, ballistic ejecta, and crater incandescence (BGVN 46:01). This report updates similar activity from January through June 2021 and uses information primarily from the Japan Meteorological Agency (JMA) and various satellite data.

During the reporting period, the number of eruptions had decreased significantly compared to previous months; at the Minamidake crater there were about 127 ash eruptions, 83 of which were explosive (compared to 432 and 221, respectively during the previous year). No eruptions were reported in the Showa crater through June. Ash was reported most frequently during March and April for 14 and 22 days, respectively (table 25). The tallest ash plume reached 4 km above the crater on 27 March, while the most amount of ashfall was 42 g/m2 during April. A decline in eruptive events after April was reflected both in JMA reports and thermal data (figure 118). Sentinel-2 infrared and natural color satellite imagery captured both thermal anomalies in the summit craters as well as significant ash plumes that resulted from the explosive eruptions (figure 119). Recorded sulfur dioxide emissions were relatively high during the beginning of the year and began to decrease to 1,300 tons/day in May.

Table 25. Number of monthly explosive eruptions, total eruptions, days of ashfall, ashfall amounts, and sulfur dioxide emissions from Sakurajima’s Minamidake crater at Aira during January-June 2021. Note that smaller events that did not reach the threshold of explosions or eruptions also occurred. Ashfall was measured at Kagoshima Local Meteorological Observatory. Data courtesy of JMA.

Month Explosive eruptions Ash eruptions Days of ashfall Ashfall amount (g/m2) SO2 emissions (tons/day)
Jan 2021 18 21 7 3 1,500-5,000
Feb 2021 11 22 7 11 1,100-4,300
Mar 2021 14 31 14 21 1,800-2,900
Apr 2021 34 42 22 42 1,800-2,900
May 2021 6 11 4 16 1,300
Jun 2021 0 -- 1 Less than 0.5 600-2,700
Figure (see Caption) Figure 118. Clusters of low-intensity thermal anomalies were detected at Aira’s Sakurajima volcano during January-June 2021 based on the MIROVA graph (Log Radiative Power). The number of relatively higher thermal anomalies seemed to decrease after April. Courtesy of MIROVA.
Figure (see Caption) Figure 119. Sentinel-2 infrared satellite images showing white gas-and-steam plumes rising from Aira’s Sakurajima volcano on 31 January (top left) 2021 accompanied by a thermal anomaly in the summit crater and two thermal anomalies in the summit crater on 21 April (bottom right). On 5 February (top right) and 27 March (bottom left) natural color satellite images showed distinct ash plumes drifting NE and NW, respectively, due to explosive eruptions. Images using “Atmospheric penetration” (bands 12, 11, 8A) rendering on 31 January and 21 April, and “Natural Color” (bands 4, 3, 2) rendering on 5 February and 27 March. Courtesy of Sentinel Hub Playground.

During January a total of 21 ash eruptions were detected, 18 of which were explosive. The number of volcanic earthquakes notably increased from 55 in December 2020 to 117, accompanied by white gas-and-steam emissions that rose 200 m above the crater and nighttime crater incandescence, as captured by a high-sensitivity surveillance camera. An explosion at 1642 on 4 January produced an ash plume that rose 1.8 km above the Minamidake crater. On 31 January an explosion at 0720 generated an ash plume that rose 2.3 km above the crater and ejected bombs 1.3-1.7 km high. JMA reported that sulfur dioxide emissions had been high since September 2020, and during January reported 1,500-5,000 tons/day, with the highest value recorded on 6 January. During seven days in the month, 3 g/m2 of ash fell, according to the Kagoshima Local Meteorological Observatory in Higashikorimoto (11 km WSW). Overall, about 100,000 tons of ash had fallen during the month.

Similar eruptive events continued in February, with 22 ash eruptions, 11 of which were explosive and ejected volcanic bombs 1-1.3 km from the Minamidake crater. The number of volcanic earthquakes increased to 292. During seven days of the month, ashfall was reported, accumulating to 11 g/m2; observation data showed that about 90,000 tons of ash had fallen during the month. SO2 emissions were between 1,100-4,300 tons/day, the higher of which was measured on 16 February. On 28 February an explosion at 2247 ejected bombs up to 1.3 km from the summit, produced an ash plume that rose 2.3 km above the crater, and was accompanied by crater incandescence.

Activity increased slightly during March and April, with 31 and 42 ash eruptions, respectively. The number of volcanic earthquakes decreased slightly from 195 in March to 148 in April. Explosions ejected incandescent material as far as 1.7 km from the Minamidake crater, accompanied by nighttime crater incandescence. An explosion on 5 March generated an ash plume that rose 2.7 km above the crater and ejected material as far as 1.1 km from the summit. On 27 March an eruption at 0236 produced an ash plume that rose 2.5-4 km above the crater and drifted NW, resulting in a large amount of ashfall in Kagoshima City (10 km W) (figure 120). Bombs were ejected up to 1.3 km from the crater. On 29 March at 1557 an ash plume rose 2.2 km above the crater and drifted SE, an accompanying pyroclastic flow was observed down the SE flank and ashfall was reported in Kagoshima City and the Kagoshima Prefecture. An explosion on 30 March at 0433 generated an ash plume 2.7 km above the crater and drifted E, ejecting material as far as 900 m from the crater and resulting in ashfall in Kagoshima City. Ashfall was reported on 14 days in March (21 g/m2) and 22 days in April (42 g/m2). A single thermal alert was detected by the MODVOLC system on 4 April; an explosion the following morning at 0641 on 5 April produced an ash plume 3 km above the crater. On 25 April an explosion at 0109 ejected material 1-1.3 km from the crater and an ash plume 2.3 km high. The explosion generated what was initially described as a pyroclastic flow that descended 1.8 km down the SW side of the crater; later field inspections did not observe pyroclastic flow deposits or damaged vegetation, and concluded that the plume was generated by winds. About 110,000-120,000 tons of ash was measured during the two months, and sulfur dioxide emissions remained consistent at 1,800-2,900 tons/day, according to JMA.

Figure (see Caption) Figure 120. Webcam images of Aira’s Sakurajima volcano showing dense gray ash plumes on 27 March (top left) rising 3.2 km above the crater, on 6 May (bottom left) rising 2.5 km above the crater, and on 28 April (right) 2021 incandescent material was visible on the flanks of the volcano accompanied by a small ash plume. Images courtesy of JMA (Sakurajima March, April, and May 2021 monthly reports).

During May and June, the number of eruptive events declined; 11 eruptions were detected during May, six of which were explosive and ejected material 800-1,100 m from the crater. On 6 May an explosion produced an ash plume that rose 2.5 km above the crater (figure 120). In June small, intermittent eruptions were detected, though none were explosive. Resulting ash plumes rose 1-2.5 km above the crater and were accompanied by nighttime crater incandescence, based on imagery from a high-sensitivity surveillance camera. The number of volcanic earthquakes continued to decrease each month from 91 to 18, respectively. During May ashfall was reported for four days, accumulating to 16 g/m2; about 50,000 tons of ash was measured. Less than 0.5 g/m2 was reported over the course of a day in June. SO2 emissions also gradually decreased from May at 1,300 tons/day to 600-2,700 tons/day in June.

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); Hawai'i Institute of Geophysics and Planetology (HIGP) - MODVOLC Thermal Alerts System, School of Ocean and Earth Science and Technology (SOEST), Univ. of Hawai'i, 2525 Correa Road, Honolulu, HI 96822, USA (URL: http://modis.higp.hawaii.edu/); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


January 2022 (BGVN 47:01) Citation IconCite this Report

Minor ash emissions July-December 2021

Sakurajima rises from Kagoshima Bay, which fills the Aira Caldera near the southern tip of Japan's Kyushu Island. Frequent explosive and occasional effusive activity has been ongoing for centuries. The Minamidake summit cone and crater has been the location of persistent activity since 1955; the Showa crater on its E flank has also been intermittently active since 2006. Explosions and ash-bearing emissions have continued primarily at the Minamidake crater since the latest eruptive episode began in late March 2017. This report covers ongoing activity at Minamidake from July through December 2021; the Japan Meteorological Agency (JMA) provides monthly reports on activity, and the Tokyo VAAC (Volcanic Ash Advisory Center) issues information about the ash emissions.

Activity decreased significantly during the second half of 2021 beginning in May (BGVN 46:08). The number of monthly explosions and ash emissions were both much lower compared with the first half of the year (table 26), as was the amount of ashfall recorded around the volcano. Thermal energy remained at low levels throughout the period (figure 121) although incandescence was visible from the webcams at night when the weather was clear. Very few ash emissions were reported each month, and ash plumes never rose more than 1,300 m above the summit (figure 122). All of the activity originated from the Minamidaki crater; there were no reports of activity from the Showa crater.

Table 26. Number of monthly explosive events, ash emission events, days of ashfall, ashfall amounts, and sulfur dioxide emissions from Sakurajima’s Minamidake crater at Aira during July-December 2021. Note that smaller ash events are not listed. Ashfall days were measured at Kagoshima Local Meteorological Observatory, and ashfall amounts represent material covering all of the Kagoshima Prefecture. Data courtesy of JMA monthly reports.

Month Explosive events Ash emission events Days of ashfall Ashfall amount (g/m2) SO2 emissions (tons/day)
Jul 2021 0 1 6 1 800-1,000
Aug 2021 0 0 0 0 600-1,500
Sep 2021 0 4 5 3 700-2,600
Oct 2021 1 1 5 Less than 0.5 400-1,000
Nov 2021 0 4 5 Less than 0.5 700-1,200
Dec 2021 0 7 2 Less than 0.5 600-1,200
Figure (see Caption) Figure 121. Thermal energy remained very low at Sakurajima in the Aira caldera throughout the second half of 2021 according to the MIROVA graph of Log Radiative Power from 3 May through December 2021. Courtesy of MIROVA.
Figure (see Caption) Figure 122. Few ash emissions were observed at Aira’s Sakurajima volcano during July-December 2021, and the ash plume heights never exceeded 1,300 m above the crater rim. The ash emission from the Minamidake summit crater on 28 July 2021 (left) rose 1,300 m above the crater rim as seen from the Kaigata surveillance camera. The ash plume on 26 September 2021 (right) rose to 1,100 m above the crater rim. Courtesy of JMA monthly reports.

There were 61 volcanic earthquakes reported during July, up from 18 in June. Less than a minute of volcanic tremors were recorded during the month, a significant drop from the 22 minutes in June. At the Kagoshima Local Meteorological Observatory, located in Higashikorimoto about 11 km WSW of Minamidake, the total amount of ashfall measured during the six days it was recorded was 1 g/m2. The total ashfall for Kagoshima Prefecture during July was about 10,000 tons. JMA reported 800-1,000 tons/day of SO2 emissions in July. An explosion on 28 July produced an ash plume that rose 1,300 m above the crater rim; no large volcanic bombs were reported. The Tokyo VAAC reported the ash emission on 28 July as rising to 2.4 km altitude and drifting NW. Two small ash emissions occurred at Minamidake on 2 and 10 August 2021. The ash plume on 10 August rose 900 m above the crater rim. 143 volcanic earthquakes were recorded during the month with 5 minutes of volcanic tremor. No ashfall was reported at the Observatory and the total ashfall around the Prefecture for August was about 5,000 tons. JMA reported 600-1,500 tons/day SO2 emissions during August.

During September 2021 four significant ash emissions events occurred at Minamidake crater and a few very small events, but no larger explosions. On 19 September the Tokyo VAAC reported an ash emission that rose to 2.1 km altitude and remained stationary. The tallest ash plume, on 26 September, rose 1,100 m above the crater rim. Seismometers recorded 124 volcanic earthquakes and three minutes of volcanic tremor. JMA reported 700-2,600 tons/day SO2 emissions, increasing somewhat at the end of the month. Inclinometers and extensometers recorded slight inflation of the volcano beginning on 13 September after a long period with little change. At the Observatory, ashfall was reported on five days with a total amount measured of 3 g/m2. The September total ash mass for the Prefecture was estimated at around 10,000 tons.

One explosion occurred from Minamidake crater on 8 October 2021 that sent volcanic bombs 600-900 m from the crater, the largest event of the period. Clouds prevented visual observations during the explosion. Other smaller ash emission events were also recorded. There were 51 volcanic earthquakes and no tremors recorded during the month. Incandescence from the summit crater was visible throughout the month (figure 123). Sulfur dioxide emissions ranged from 400-1,000 tons/day; they increased temporarily during the second half of September. Inflation of the volcano that was measured from the GNSS observations beginning in mid-September slowed in the beginning of October and ceased by mid-month. Ashfall was recorded at the Observatory on five days during the month with a total amount of 0.5 g/m2 measured. The total ashfall in the Kagoshima Prefecture for October was estimated at 7,000 tons. No particular changes were observed at the Minamidake and Showa craters during an overflight on 18 October 2021. On 31 October the Tokyo VAAC reported an ash emission that rose to about 2.4 km altitude. Clear Sentinel images from 3 and 28 October showed a moderate thermal anomaly at vent “A” in Minamidake crater.

Figure (see Caption) Figure 123. Incandescence was visible from the Minamidake summit crater at Sakurajima in the Aira caldera on 14 October 2021, and on most clear nights throughout the period. Courtesy of JMA Annual Report for 2021.

Four recorded ash emission events were recorded by JMA at Minamidake crater during November 2021, and a few other much smaller events, but no large explosions took place. Ash emissions rose to a maximum height of 1,300 m above the crater rim. On 2 November the Tokyo VAAC reported an ash emission that rose to 2.4 km altitude and drifted SW. On 18 November two ash emissions also rose to 2.4 km altitude; one drifted SE and the other drifted NE. Observers on an overflight on 20 November saw no notable changes at the craters or surrounding summit area. An ash emission on 25 November rose to 2.1 km altitude and drifted E. Seismometers detected 57 volcanic earthquakes and no tremors during the month. Field measurements of SO2 indicated 700-1,200 tons/day were released by the volcano. Inclinometers and extensometers showed inflation during November. Ashfall total measured at the Observatory was less than 0.5 g/m2 over five days. The estimate of total ashfall in the prefecture for November was 5,000 tons. Clear skies on 2, 7, and 27 November revealed a thermal anomaly inside the Minamidake crater. In addition, a second faint thermal anomaly was visible inside the Minamidake crater on 27 November at vent ‘B’ (figure 124).

Figure (see Caption) Figure 124. Clear skies on 2 (left) and 27 (right) November 2021 revealed thermal anomalies within the Minamidake crater at Aira’s Sakurajima volcano. The brighter anomaly in both images is from vent A, and the fainter anomaly is vent B. Sentinel 2 satellite images use Atmospheric penetration rendering (bands 12, 11, and 8a). Courtesy of Sentinel Hub Playground.

During December 2021 larger ash emission events occurred seven times, an increase from previous months, and a few smaller events were also noted. The tallest ash plume rose 1,300 m above the crater rim on 2 December; the Tokyo VAAC reported the emission at 2.4 km altitude drifting SE. During an overflight on 8 December, no specific changes were visible at the summit crater area (figure 125). On 9 December an ash plume rose to 2.1 km altitude and drifted E. The next day two emissions rose to 2.4 km; one drifted NE. On 20 December an ash emission rose to 2.1 km altitude and drifted E. On 21 and 28 December ash plumes rose to 2.4 km and extended SE and E. Seismometers measured 136 volcanic earthquakes and less than one minute of tremor that was associated with very small ash emission events. Field measurements indicated 600-1,200 tons of SO2 were released daily. Inflation of the volcano decreased during December. Only slight ashfall (less than 0.5 g/m3) was recorded on two days of the month at the Observatory. A single thermal anomaly was visible inside the crater in Sentinel satellite imagery on 7 December, but an ash emission was visible on 22 December (figure 126).

Figure (see Caption) Figure 125. The Minimidake and Showa craters at the summit of Sakurajima in the Aira caldera seen in this aerial photo. Two active vents, A and B, are within the Minamidake crater. Image taken during an overflight on 8 December 2021. Courtesy of JMA Monthly Report.
Figure (see Caption) Figure 126. An ash emission rose from the Minamidake crater at Aira caldera’s Sakurajima volcano on 22 December 2021 and was recorded by this Natural color rendering (bands 4, 3, 2) Sentinel 2 satellite image. Courtesy of Sentinel Hub Playground.

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


July 2022 (BGVN 47:07) Citation IconCite this Report

Explosive events, plumes, minor ashfall, and crater incandescence during January-June 2022

The Aira caldera in the northern half of Kagoshima Bay contains the active post-caldera Sakurajima volcano near the southern tip of Japan’s Kyushu Island. Eruptions date back to the 8th century, which have deposited ash on Kagoshima, 8 km from the summit. The Minamidake summit cone and crater has had persistent activity since 1955; the Showa crater on the E flank has also been intermittently active since 2006. More recent activity has consisted of minor ash emissions, low thermal activity, and ashfall events (BGVN 47:01). The current eruption period began in late March 2017, characterized by some explosions and ash emissions in the Minamidake crater. This report updates information from January through June 2022 using monthly activity from the Japan Meteorological Agency (JMA), the Tokyo Volcanic Ash Advisory Center (VAAC), and various satellite data.

Low levels of activity from the Minamidake crater during this reporting period dominantly consisted of volcano-tectonic earthquakes, eruption plumes, and nighttime incandescence, with the addition of some explosions, ashfall, and sulfur dioxide emissions (table 27). Reports of activity in the Showa crater mainly described occasional white gas-and-steam emissions. Thermal activity remained at low levels throughout the period (figure 127), though summit crater incandescence was frequently reported at night during clear weather. Some thermal anomalies at the Minamidake crater were visible in Sentinel-2 infrared satellite imagery (figure 128).

Table 27. Number of monthly explosive events, days of ashfall, area of ash covered, and sulfur dioxide emissions from Sakurajima’s Minamidake crater at Aira during January-June 2022. Note that smaller ash events are not listed. Ashfall days were measured at Kagoshima Local Meteorological Observatory, and ashfall amounts represent material covering all the Kagoshima Prefecture. Data courtesy of JMA monthly reports.

Month Explosive events Days of ashfall Ashfall amount (g/m2) SO2 emissions (tons/day)
Jan 2022 5 1 Less than 0.5 400-1,000
Feb 2022 0 2 Less than 0.5 700-1,700
Mar 2022 0 0 0 800-1,300
Apr 2022 0 0 0 500-1,300
May 2022 0 3 Less than 0.5 500-1,700
Jun 2022 1 0 0 800-1,200
Figure (see Caption) Figure 127. Thermal activity at Sakurajima in the Aira caldera remained relatively low during January through June 2022, according to this MIROVA graph (Log Radiative Power). Three anomalies were detected during January, three during late February, three during early March, four during April, and one during early June. Courtesy of MIROVA.
Figure (see Caption) Figure 128. Sentinel-2 infrared satellite imagery showed weak thermal anomalies in the Minamidake crater at Aira’s Sakurajima volcano on 1 January 2022 (top left), 25 February 2022 (top right), 16 April 2022 (bottom left), and 30 June 2022 (bottom right). The brighter anomaly in the 1 January image is from vent A, while the fainter anomaly is vent B; both vents A and B are part of the Minamidake crater. The anomalies notably decreased in strength during 25 February and 16 April. On 30 June a stronger anomaly was visible in vent B, but clouds covered visibility in vent A. Images use “Atmospheric penetration” rendering (bands 12, 11, and 8a). Courtesy of Sentinel Hub Playground.

There were 103 volcanic earthquakes reported during January, a decrease from December 2021 (136). Additionally, a field survey reported that 400-1,000 tons/day (t/d) of sulfur dioxide emissions were emitted during the month, compared to December (600-1,200 t/d). Eruption plumes rose 1-2 km above the crater and drifted E and SE following eruption events detected on 1, 7, and 18 January. Nighttime crater incandescence was also visible on these days, based on surveillance cameras. On 7 and 18 January large volcanic blocks were ejected 600-900 m and 1-1.3 km from the Minamidake crater. Two eruptions were detected at the Minamidake crater on 28 January, one of which was described as an explosion; at 1319 a plume rose as high as 3.4 km above the crater and material traveled 1.3-1.7 km from the Minamidake summit crater (figure 129); crater incandescence accompanied this event. That same day, a field survey reported that ashfall was observed in Arimura Town (753 g/m2) and Kurokami-cho, according to JMA (figure 129).

Figure (see Caption) Figure 129. Webcam image of the explosion at the Minamidake summit crater of Aira’s Sakurajima at 1319 on 28 January 2022 (left). The resulting plume rose 3.4 km above the crater rim. Ashfall from the event was observed on 28 January in Arimura Town; about 753 g/m2 was recorded (right). Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, January 2022).

Activity during February was relatively low and consisted of 22 volcanic earthquakes and eruption events at 1620 on 13 February and 1540 on 15 February. A field survey reported that 700-1,700 t/d of sulfur dioxide emissions were measured during this month. The event on 13 February the eruption plume rose 1 km above the crater and drifted SE and on 15 February the plume rose 1.3 km above the crater and drifted E. Similar low activity during March and April was characterized by 36 and 37 volcanic earthquakes, respectively, and intermittent crater incandescence, based on surveillance camera data. Sulfur dioxide emissions were 800-1,300 t/d during March and 500-1,300 t/d during April. An eruption event on 17 March produced a small plume that rose 600 m above the crater rim, and one on 20 April sent a plume 900 m above the crater (figure 130).

Figure (see Caption) Figure 130. Webcam image of the eruption event at Sakurajima’s Minamidake crater at 1243 on 20 April 2022. The eruption plume rose 900 m above the crater rim. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, April 2020).

During May, the number of volcanic earthquakes detected increased to 154 and the sulfur dioxide emissions ranged from 500 to 1,700 t/d. An eruption at 1453 on 3 May generated a plume that rose 1 km above the crater. On 15 May an eruption event at 1141 produced a plume that rose 1.2 km above the crater. Another eruption event on 17 May occurred at 0900 and produced plumes that rose 1.5 km above the crater (figure 131). Nighttime crater incandescence also accompanied this event, based on high-sensitivity surveillance cameras. Volcanic tremors were detected during 17-19 May and JMA reported that there was a notable increase in the number of tremors on 19 May. Intermittent incandescence was visible at the Minamidake crater throughout the rest of the month. Activity during June remained consistent, with frequent nighttime incandescence and 57 volcanic earthquakes. Daily sulfur dioxide emissions were 800-1,200 t/d during June. Eruption events reported by JMA on 27, 28, and 29 June generated eruption plumes that rose 1.2-1.6 km above the crater and drifted NE. An explosion on 27 June at 1221 produced an eruption plume that rose 1.6 km above the crater and ejected volcanic blocks 600-900 m from the Minamidake crater.

Figure (see Caption) Figure 131. Webcam image of the eruption event at Sakurajima’s Minamidake crater at 0900 on 17 May 2022. The eruption plume rose 1.5 km above the crater rim. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, May 2022).

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).


January 2023 (BGVN 48:01) Citation IconCite this Report

Explosions, ash plumes, and ashfall during July-December 2022

Aira caldera is located in the northern half of Kagoshima Bay and contains the active post-caldera Sakurajima volcano near the southern tip of Japan’s Kyushu Island. Frequent historical eruptions have been recorded since the 8th century and have deposited ash on Kagoshima, one of Kyushu’s largest cities, 10 km W from the summit. The largest recorded eruption took place during 1471-76. The current eruption period began during late March 2017 and has more recently consisted of explosive events, eruption plumes, minor ashfall, and crater incandescence (BGVN 47:07). This report updates information from July through December 2022 using monthly activity from the Japan Meteorological Agency (JMA) and satellite data.

Thermal activity remained at low levels during the reporting period; only two anomalies were detected each month during late July and early August, and there was a brief period of no registered thermal data during mid-August through most of September (figure 132). After late October, the frequency of thermal anomalies increased slightly and up to two anomalies were observed in the Minamidake crater in Sentinel-2 infrared satellite imagery during the latter part of the year (figure 133).

Table 28. Number of monthly explosive events, days of ashfall, area of ash covered, and sulfur dioxide emissions from Sakurajima’s Minamidake crater at Aira during July-December 2022. Note that smaller ash events are not listed. Ashfall days were measured at Kagoshima Local Meteorological Observatory, and ashfall amounts represent material covering all the Kagoshima Prefecture. Data courtesy of JMA monthly reports.

Month Explosive events Days of ashfall Ashfall amount (g/m3) SO2 emissions (tons/day)
Jul 2022 12 6 28 1,400-3,200
Aug 2022 16 0 0 1,500-2,500
Sep 2022 23 14 53 1,900-2,400
Oct 2022 12 18 24 1,900-4,000
Nov 2022 5 10 9 700-1,900
Dec 2022 11 8 12 1,400-2,800
Figure (see Caption) Figure 132. Thermal activity at Sakurajima in the Aira caldera was relatively low during late July through December 2022, according to this MIROVA graph (Log Radiative Power). Two thermal anomalies were recorded during each month of late July and early August. No thermal activity was detected for a brief period during mid-August through most of September. The number of anomalies increased after mid-October and continued through the end of the year. Courtesy of MIROVA.
Figure (see Caption) Figure 133. Sentinel-2 infrared satellite imagery showed small thermal anomalies in the Minamidake crater at Aira’s Sakurajima volcano on 28 September 2022 (top left), 18 October 2022 (top right), and 27 November 2022 (bottom left). Vent A is located to the left and Vent B is to the right of Vent A; both vents are part of the Minamidake crater. Clouds covered Vent B on 28 September. A gas-and-steam emission covered the crater on 12 December 2022 (bottom right). Images use “Atmospheric penetration” rendering (bands 12, 11, and 8a). Courtesy of Sentinel Hub Playground.

JMA reported that during July there were 37 eruption events detected, 12 of which were explosion events. Accompanying eruption plumes rose 2.8 km above the crater rim. Nighttime incandescence was observed in the Minamidake crater using a high-sensitivity surveillance camera. No eruptions in the Showa crater were reported. Seismicity consisted of 146 volcanic earthquakes, which had increased compared to 57 earthquakes in June. According to field surveys, daily sulfur dioxide emissions ranged 1,400-3,200 tons/day (t/d). The Kagoshima Local Meteorological Observatory reported a total of 28 g/m2 of ashfall was observed during 6 days. On 17 July an explosion at 1852 generated an eruption plume that rose 2.8 km above the crater rim and large volcanic blocks were ejected 800-1,100 m above the crater rim (figure 134).

Figure (see Caption) Figure 134. Webcam image of the explosions at the Minamidake summit crater of Aira’s Sakurajima at 1855 on 17 July 2022. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, July 2022).

JMA reported an inflation event was first detected around 0900 on 18 July and warned residents that an inflation event suggested a magmatic intrusion was occurring. A field visit reported that sulfur dioxide emissions were at 1,900 t/d. Four eruptive events were recorded between 23 July and 1500 on 24 July that produced plumes that rose 1.2 km above the crater rim. A larger explosion at 2005 on 24 July ejected large volcanic blocks 2.4-2.5 km E. The accompanying volcanic plume rose 300 m above the crater rim and mixed with meteoric clouds. The last time an explosion ejected material more than 2 km from the crater was on 4 June 2020, according to JMA. The Volcano Alert Level (VAL) was briefly raised from 3 to 5 (on a 5-level scale) at 2050, signaling that the residents should evacuate. Ashfall was reported in Kagoshima City (10 km W). JMA noted that inflation stopped after this event. A field survey was conducted by the Japan Meteorological Agency Mobile Survey Team (JMA-MOT) on 25 July and confirmed that material was deposited more than 2.4 km from the vent, and they observed ashfall in an area from Shirahamacho (42 km NW) to Kurokamicho (5 km SE). Ash was deposited on the E flank of the Minamidake crater, based on data from infrared thermal imaging equipment and visual observations (figure 135). During 25-26 July a few small explosions and eruptive events generated plumes that rose as high as 2.2 km above the crater rim and disappeared into meteoric clouds. After 26 July, JMA noted that material had not been ejected more than 2 km from the crater, so the VAL was lowered back to 3.

Figure (see Caption) Figure 135. Photo of ashfall in Kurokamicho taken on 25 July 2022 after the explosion at Aira’s Sakurajima on 24 July 2022. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, July 2022).

There were 71 eruptions reported during August, 16 of which were explosions. Volcanic plumes rose 2.8 km above the crater rim. Nighttime crater incandescence was observed at the Minamidake crater. There were 207 volcanic earthquakes detected during the month. According to a field survey the amount of sulfur dioxide emissions released ranged between 1,500-2,500 t/d. Ashfall was not observed. On 2 August at 0055 a volcanic plume rose 2.8 km above the crater. On 15 August at 0009 an explosion produced an eruption plume that rose 2 km above the crater rim and ejected large blocks 1.3-1.7 km above the summit.

During September there were 36 eruption events and 23 of which were explosions. Volcanic plumes rose 2.8 km above the crater rim and nighttime crater incandescence persisted. There were 319 volcanic earthquakes detected during the month. Sulfur dioxide emissions ranged between 1,900-2,400 t/d. According to the Kagoshima Local Meteorological Observatory, a total of 53 g/m2 ashfall was observed over 14 days. On 23 September at 1335 a volcanic plume rose 1.7 km above the crater rim and continued until 1600. Some ashfall was observed on the SE flank. On 30 September at 1144 an explosion rose 2.8 km above the crater rim and drifted down-flank to the SE until 1600. A large amount of ash was deposited on the SE flank. Around 0000 volcanic blocks were ejected 1.3-1.7 km from the Minamidake crater.

Eruptive activity continued during October, with 39 events reported, which included 12 explosions. Volcanic plumes rose 2.4 km above the crater rim. Nighttime crater incandescence continued. Seismicity consisted of 145 volcanic earthquakes. According to a field survey, the amount of sulfur dioxide released during the month ranged from 1,900 t/d to 4,000 t/d, the latter of which was measured on 14 October. JMA noted that the amount of volcanic gas released has been generally high since July. Ashfall measurements showed that a total of 24 g/m2 fell over 18 days at the Kagoshima Local Meteorological Observatory. An explosion was detected at 1932 on 10 October that ejected material 1.3-1.7 km from the Minamidake summit crater. A field survey conducted on 11 October confirmed weak incandescence was visible in the Minamidake crater and a geothermal area was observed on the SE flank of Minamidake, part of the inner Showa crater wall. At 1424 on 18 October an eruption plume rose 2.4 km above the crater (figure 136). Smaller eruptive events were occasionally recorded during 28-31 October.

Figure (see Caption) Figure 136. Webcam image showing an eruption plume rising 2.4 km above Aira’s Sakurajima at 1429 on 18 October 2022. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, October 2022).

JMA reported 17 eruptive events occurred during November, which included 5 explosions. Volcanic plumes rose 2.2 km above the crater rim. Nighttime crater incandescence was reported in the Minamidake crater. There were 135 volcanic earthquakes detected throughout the month. The amount of sulfur dioxide emissions ranged from 700 t/d to 1,900 t/d and a total amount of 9 g/m2 of ashfall was observed at the Kagoshima Local Meteorological Observatory over 10 days. Explosions were detected at 0515 on 4 November and 1954 on 20 November and ejected volcanic blocks 600-900 m. An explosion at 2010 on 15 November generated a volcanic plume that rose 600 m above the crater rim and drifted SE. An explosion at 1334 on 21 November generated an eruption plume that rose 2.2 km above the crater rim and ejected large blocks as far as 500 m from the vent (figure 137). Small eruptive events were also detected during 25-28 November.

Figure (see Caption) Figure 137. Webcam image of an explosion at Aira’s Sakurajima on 1336 on 21 November 2022. The accompanying volcanic plume rose 2.2 km above the crater rim. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, November 2022).

During December, JMA reported that there were 20 eruptions, 11 of which were explosions. Volcanic plumes rose as high as 3.2 km above the crater rim. Nighttime crater incandescence remained visible at the Minamidake crater. There were 78 volcanic earthquakes detected during the month. According to a field survey the amount of sulfur dioxide emissions released was 1,400-2,800 t/d. During the month, 12 g/m2 of ash fell over 8 days during the month, as observed at the Kagoshima Local Meteorological Observatory. At 0340 on 2 December a volcanic plume rose 3.2 km above the crater rim and ejected blocks as far as 1.1 km from the vent (figure 138). A second explosions was detected at 1929 on 3 December that produced an eruption plume that rose 3 km above the crater rim and ejected volcanic blocks 1-1.3 km from the crater. Webcam video of the event showed incandescent material ejected above the crater and lightning in the ash plume. Two explosions were recorded on 14 December that generated eruption plumes rising 1.7 km above the crater rim and disappearing into the meteoric clouds. Ejected blocks traveled as far as 700 m from the vent. An explosion at 0805 on 17 December produced a plume that rose 700 m above the crater rim and interacted with meteoric clouds. Ejected blocks traveled 900 m from the vent. At 0449 on 22 December ejected blocks traveled 600-900 m from the vent. On 24 December at 1954 an explosion produced an eruption plume that rose 1.2 km above the crater rim and ejected large blocks as far as 1.1 km from the vent. Two explosions on 27 and 29 December generated volcanic plumes 1.7 km above the crater rim and ejected blocks as far as 900 m from the vent.

Figure (see Caption) Figure 138. Webcam image showing the explosion in the Minamidake summit crater at Aira’s Sakurajima at 0344 on 2 December 2022. The plume rose 3.2 km above the crater rim. Photo has been color corrected. Courtesy of JMA monthly report (Sakurajima volcanic activity explanatory material, December 2022).

Information Contacts: Japan Meteorological Agency (JMA), 1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122, Japan (URL: http://www.jma.go.jp/jma/indexe.html); MIROVA (Middle InfraRed Observation of Volcanic Activity), a collaborative project between the Universities of Turin and Florence (Italy) supported by the Centre for Volcanic Risk of the Italian Civil Protection Department (URL: http://www.mirovaweb.it/); Sentinel Hub Playground (URL: https://www.sentinel-hub.com/explore/sentinel-playground).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 48 confirmed Holocene eruptive periods.

2017 Mar 25 - 2024 Mar 1 (continuing) Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Minamidake summit crater
2017 Mar 25 - 2024 Mar 1 (continuing) Evidence from Observations: Reported

List of 4 Events for Episode 1 at Minamidake summit crater

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - VEI (Explosivity Index)

1955 Oct 13 - 2016 Aug 22 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode Minami-dake and east flank (Showa crater)
1955 Oct 13 - 2016 Aug 22 Evidence from Observations: Reported

List of 23 Events for Episode 1 at Minami-dake and east flank (Showa crater)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Pyroclastic flow weak or small
   - - - -    - - - - Lava lake Small
   - - - -    - - - - Lava dome
   - - - -    - - - - Ash
   - - - -    - - - - Bombs
   - - - -    - - - - Blocks
   - - - -    - - - - Pumice
   - - - -    - - - - Flames
   - - - -    - - - - Lightning
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
1955 Oct 13    - - - - Fatalities
1955 Oct 13    - - - - VEI (Explosivity Index)
1961 Dec    - - - - VEI (Explosivity Index)
1973 Jun 1    - - - - VEI (Explosivity Index)
1974 Jun 17    - - - - Fatalities
1974 Aug 9    - - - - Fatalities
2010 Feb 8    - - - - Lightning Lava fountaining on 8 February 2010 reached 1,000 m above the crater; this activity was visible at night and lightning was observed within the ash plume.
2013 Aug 18    - - - - Eruption cloud Height of 5 km above crater rim; highest since recording began in 2006.

[ 1954 Nov 16 ± 15 days - 1954 Dec 16 ± 15 days ] Uncertain Eruption

Episode 1 | Eruption Episode Minami-dake
1954 Nov 16 ± 15 days - 1954 Dec 16 ± 15 days Evidence from Unknown

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
1954 Nov    - - - - VEI (Explosivity Index)

1950 Jun 29 - 1950 Sep 9 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Minami-dake
1950 Jun 29 - 1950 Sep 9 Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity weak or small
   - - - -    - - - - Ash
1950 Jun 29    - - - - VEI (Explosivity Index)

1948 Jul 27 - 1948 Jul 27 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode East flank of Minami-dake (750 m)
1948 Jul 27 - 1948 Jul 27 Evidence from Observations: Reported

List of 4 Events for Episode 1 at East flank of Minami-dake (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Audible Sounds
1948 Jul 27    - - - - VEI (Explosivity Index)

1946 Jan - 1946 Nov Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode East flank of Minami-dake (750 m)
1946 Jan - 1946 Nov Evidence from Observations: Reported

List of 10 Events for Episode 1 at East flank of Minami-dake (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic)
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Ash
   - - - -    - - - - Blocks
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Property Damage
1946    - - - - Fatalities
1946 Jan    - - - - VEI (Explosivity Index)

1942 Jul 16 - 1942 Jul 16 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode East flank of Minami-dake (750 m)
1942 Jul 16 - 1942 Jul 16 Evidence from Observations: Reported

List of 5 Events for Episode 1 at East flank of Minami-dake (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Bombs
1942 Jul 16    - - - - VEI (Explosivity Index)

1941 Apr 28 - 1941 Aug 26 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode East flank of Minami-dake (750 m)
1941 Apr 28 - 1941 Aug 26 Evidence from Observations: Reported

List of 5 Events for Episode 1 at East flank of Minami-dake (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Bombs
1941 Apr 28    - - - - VEI (Explosivity Index)

1940 Apr 24 - 1940 Jul 9 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake and east flank (750 m)
1940 Apr 24 - 1940 Jul 9 Evidence from Observations: Reported

List of 4 Events for Episode 1 at Minami-dake and east flank (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Scoria
1940 Apr 24    - - - - VEI (Explosivity Index)

1939 Oct 26 - 1939 Nov 12 (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode East flank of Minami-dake (750 m)
1939 Oct 26 - 1939 Nov 12 (?) Evidence from Observations: Reported

List of 7 Events for Episode 1 at East flank of Minami-dake (750 m)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic)
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow weak or small
   - - - -    - - - - Ash
   - - - -    - - - - Bombs
   - - - -    - - - - Blocks
1939 Oct 26    - - - - VEI (Explosivity Index)

1938 Feb 25 - 1938 Mar 31 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1938 Feb 25 - 1938 Mar 31 Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Phreatic activity Uncertain
   - - - -    - - - - Ash
1938 Feb 25    - - - - VEI (Explosivity Index)

1935 Sep 20 - 1935 Sep 24 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Minami-dake
1935 Sep 20 - 1935 Sep 24 Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
1935 Sep 20    - - - - VEI (Explosivity Index)

1914 Jan 12 - 1915 May Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode West, east and SE flanks
1914 Jan 12 - 1915 May Evidence from Observations: Reported

List of 12 Events for Episode 1 at West, east and SE flanks

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Seismicity (volcanic) Before eruption.
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Ash
   - - - -    - - - - Earthquake (tectonic)
   - - - -    - - - - Deformation (deflation)
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
1914 Jan 12    - - - - Fatalities
1914 Jan 12    - - - - VEI (Explosivity Index)

[ 1899 Sep 24 - 1899 Sep 25 ] Uncertain Eruption

Episode 1 | Eruption Episode Minami-dake
1899 Sep 24 - 1899 Sep 25 Evidence from Unknown

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Volcanic "smoke"
1899 Sep 24    - - - - VEI (Explosivity Index)

1860 Confirmed Eruption Max VEI: 1

Episode 1 | Eruption Episode Minami-dake
1860 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
1860    - - - - VEI (Explosivity Index)

1799 Mar 27 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1799 Mar 27 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1799 Mar 27    - - - - VEI (Explosivity Index)

1797 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1797 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1797    - - - - VEI (Explosivity Index)

1794 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1794 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1794    - - - - VEI (Explosivity Index)

[ 1792 ] Uncertain Eruption

Episode 1 | Eruption Episode Minami-dake
1792 - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
1792    - - - - VEI (Explosivity Index)

1791 Sep 11 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1791 Sep 11 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1791 Sep 11    - - - - VEI (Explosivity Index)

1790 Jul 29 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1790 Jul 29 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1790 Jul 29    - - - - VEI (Explosivity Index)

1785 Nov 20 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode
1785 Nov 20 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1785 Nov 20    - - - - VEI (Explosivity Index)

1783 Sep 3 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode
1783 Sep 3 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
1783 Sep 3    - - - - VEI (Explosivity Index)

1782 Jan 18 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode NE flank (offshore)
1782 Jan 18 - Unknown Evidence from Observations: Reported

List of 1 Events for Episode 1 at NE flank (offshore)

Start Date End Date Event Type Event Remarks
1782 Jan 18    - - - - VEI (Explosivity Index)

1779 Nov 8 - 1781 May Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode NE flank, off NE coast, south flank
1779 Nov 8 - 1781 May Evidence from Observations: Reported

List of 20 Events for Episode 1 at NE flank, off NE coast, south flank

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Eruption cloud
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Ash violent, strong, or large
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Earthquakes (undefined)
   - - - -    - - - - Island
   - - - -    - - - - Lahar or Mudflow
   - - - -    - - - - Tsunami
   - - - -    - - - - Fauna Kill Terrestrial.
   - - - -    - - - - Property Damage
   - - - -    - - - - Evacuations
1779 Nov 8    - - - - VEI (Explosivity Index)
1779 Nov 9    - - - - Fatalities
1780 Feb 9    - - - - Fatalities
1780 Sep    - - - - VEI (Explosivity Index)
1781 Apr    - - - - VEI (Explosivity Index)
1781 Apr 11    - - - - Fatalities

[ 1766 Jun 5 ] Discredited Eruption

1756 Sep 9 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1756 Sep 9 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1756 Sep 9    - - - - VEI (Explosivity Index)

1749 Sep Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake summit, west flank?
1749 Sep - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake summit, west flank?

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow Uncertain
1749 Sep    - - - - VEI (Explosivity Index)

1742 Apr 6 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Minami-dake
1742 Apr 6 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1742 Apr 6    - - - - VEI (Explosivity Index)

1706 Jan Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Minami-dake
1706 Jan - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1706 Jan    - - - - VEI (Explosivity Index)

1678 Mar 1 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Minami-dake
1678 Mar 1 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1678 Mar 1    - - - - VEI (Explosivity Index)

[ 1670 Jun 1 ] Uncertain Eruption

Episode 1 | Eruption Episode
1670 Jun 1 - Unknown Evidence from Unknown

List of 1 Events for Episode 1

Start Date End Date Event Type Event Remarks
1670 Jun 1    - - - - VEI (Explosivity Index)

1642 Apr 6 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Minami-dake
1642 Apr 6 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1642 Apr 6    - - - - VEI (Explosivity Index)

1478 Sep 23 Confirmed Eruption Max VEI: 2 (?)

Episode 1 | Eruption Episode Minami-dake
1478 Sep 23 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Property Damage
1478 Sep 23    - - - - VEI (Explosivity Index)

1471 Nov 3 - 1476 Oct 8 (in or after) Confirmed Eruption Max VEI: 5 (?)

Episode 1 | Eruption Episode NE and SW flanks, summit crater
1471 Nov 3 - 1476 Oct 8 (in or after) Evidence from Observations: Reported

List of 12 Events for Episode 1 at NE and SW flanks, summit crater

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Pumice
   - - - -    - - - - Earthquakes (undefined) Before.
   - - - -    - - - - Property Damage
1471    - - - - Fatalities
1471 Nov 3    - - - - VEI (Explosivity Index)
1473 Mar    - - - - VEI (Explosivity Index)
1475 Sep 24    - - - - VEI (Explosivity Index)
1476 Oct 8    - - - - VEI (Explosivity Index)

1468 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Minami-dake
1468 - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
1468    - - - - VEI (Explosivity Index)

0778 Confirmed Eruption Max VEI: 0 (?)

Episode 1 | Eruption Episode
0778 - Unknown Evidence from Observations: Reported

List of 1 Events for Episode 1

Start Date End Date Event Type Event Remarks
0778    - - - - VEI (Explosivity Index)

0766 Jul 20 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode
0766 Jul 20 - Unknown Evidence from Observations: Reported

List of 4 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Island
0766    - - - - Fatalities
0766 Jul 20    - - - - VEI (Explosivity Index)

0764 Jan Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode East flank (Nabe-yama), Sz-4 tephra
0764 Jan - Unknown Evidence from Observations: Reported

List of 9 Events for Episode 1 at East flank (Nabe-yama), Sz-4 tephra

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Phreatic activity
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.
   - - - -    - - - - Pumice
   - - - -    - - - - Property Damage
0764 Jan    - - - - Fatalities
0764 Jan    - - - - VEI (Explosivity Index)

0716 - 0718 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode
0716 - 0718 Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
   - - - -    - - - - Island
0716    - - - - VEI (Explosivity Index)

[ 0712 ] Uncertain Eruption

Episode 1 | Eruption Episode
0712 - Unknown Evidence from Unknown

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
0712    - - - - VEI (Explosivity Index)

0708 Confirmed Eruption Max VEI: 3

Episode 1 | Eruption Episode
0708 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion Uncertain
   - - - -    - - - - Island
0708    - - - - VEI (Explosivity Index)

0650 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Minami-dake
0650 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 1 Events for Episode 1 at Minami-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion

1050 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kannonzaki lava
1050 BCE (?) - Unknown Evidence from Correlation: Magnetism

List of 2 Events for Episode 1 at Kannonzaki lava

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.

2050 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Miyamoto lava
2050 BCE (?) - Unknown Evidence from Correlation: Magnetism

List of 2 Events for Episode 1 at Miyamoto lava

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Lava flow
   - - - -    - - - - Lava flow Entered water.

2900 BCE (?) Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode Kita-dake, Tephra layer Sz-5
2900 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 3 Events for Episode 1 at Kita-dake, Tephra layer Sz-5

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pumice
2900 BCE
(?)
   - - - - VEI (Explosivity Index)

3050 BCE (?) Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode Kita-dake, Tephra layer Sz-7
3050 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1 at Kita-dake, Tephra layer Sz-7

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
3050 BCE
(?)
   - - - - VEI (Explosivity Index)

4800 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kita-dake
4800 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 1 Events for Episode 1 at Kita-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion

5400 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kita-dake
5400 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1 at Kita-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pumice

5950 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kita-dake
5950 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1 at Kita-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pumice

6050 BCE (?) Confirmed Eruption Max VEI: 5

Episode 1 | Eruption Episode Kita-dake, Tephra layer Sz-11
6050 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 3 Events for Episode 1 at Kita-dake, Tephra layer Sz-11

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pumice
6050 BCE
(?)
   - - - - VEI (Explosivity Index)

6350 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kita-dake
6350 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 1 Events for Episode 1 at Kita-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion

7750 BCE (?) Confirmed Eruption  

Episode 1 | Eruption Episode Kita-dake
7750 BCE (?) - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 1 Events for Episode 1 at Kita-dake

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion

8050 BCE ± 1000 years Confirmed Eruption Max VEI: 6

Episode 1 | Eruption Episode Wakamiko Caldera
8050 BCE ± 1000 years - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 6 Events for Episode 1 at Wakamiko Caldera

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lapilli
   - - - -    - - - - Pumice
   - - - -    - - - - Caldera Explosion
6200 BCE ± 1000 years    - - - - VEI (Explosivity Index)
Deformation History

There is data available for 3 deformation periods. Expand each entry for additional details.


Deformation during 2006 Jun - 2011 Mar [Uplift; Observed by InSAR]

Start Date: 2006 Jun Stop Date: 2011 Mar Direction: Uplift Method: InSAR
Magnitude: 2.000 cm Spatial Extent: Unknown Latitude: Unknown Longitude: Unknown

Reference List: Nobile et al. 2013*; Nobile et al. 2014*.

Full References:

Nobile, A., D. Trippanera, S. Pepe, F. Casu, P. Tizzani, J. Ruch, Y. Aoki, N. Geshi, V. Acocella, E. Sansosti, V. Siniscalchi, S. Borgstrom, S. Zoffoli, 2013. Volcano deformation in Kyushu (SW Japan) through InSAR data. (abstract 1A1_2D-O2), Prseented at the IAVCEI 2013 Scientific Assembly, Kagoshima, Japan.

Nobile, A., S. Pepe, J. Ruch, D. Trippanera, F. Casu, R. Castaldo, P. Tizzani, Y. Aoki, N. Geshi, V. Acocella, E. Sansosti, V. Siniscalchi, S. Borgstrom, S. Zoffoli, 2014. Caldera deformation in Kyushu island (SW Japan) through InSAR data. (abstract 8850), EGU General Assembly, Vienna, Austria.

Deformation during 2002 Oct 11 - 2002 Oct 11 [Variable (uplift / subsidence); Observed by Strainmeter, Tilt]

Start Date: 2002 Oct 11 Stop Date: 2002 Oct 11 Direction: Variable (uplift / subsidence) Method: Strainmeter, Tilt
Magnitude: Unknown Spatial Extent: Unknown Latitude: Unknown Longitude: Unknown

Remarks: Tilt and strain records show upward tilt 3 hours prior to eruption, and downward tilt as the explosion occurred.


Reference List: Iguchi et al. 2008.

Full References:

Iguchi M, Yakiwara H, Tameguri T, Hendrasto M, Hirabayashi J-I, 2008. Mechanism of explosive eruption revealed by geophysical observations at the Sakurajima, Suwanosejima and Semeru volcanoes. J. Volcanol. Geotherm. Res., 178, 1-9. https://doi.org/10.1016/j.jvolgeores.2007.10.010

Deformation during 1995 - 1998 [Uplift; Observed by InSAR]

Start Date: 1995 Stop Date: 1998 Direction: Uplift Method: InSAR
Magnitude: 2.000 cm Spatial Extent: Unknown Latitude: 32.000 Longitude: 131.000
Figure (see Caption)

Recorded differential JERS interferograms over the Aira Caldera encompassing the 1993?1998 period. (a) Interferogram spanning four years from June 1993 to March 1997. (b) Interferogram spanning five years from October 1993 to August 1998. (c) Interferogram spanning five years from October 1993 to September 1998. A complete cycle of phase (purple, blue yellow) represents a decrease in range of 11.73 cm between the ground surface and the satellite.

From: Remy et al. 2007.


Reference List: Remy et al. 2007.

Full References:

Remy, D., S. Bonvalot, M. Murakami, P. Briole, S. Okuyama., 2007. Inflation of the Aira Caldera (Japan) detected over Kokubu urban area using SAR interferometry ERS data. eEarth, 2 (1), pp.17-25.

Emission History

There is no Emissions History data available for Aira.

Photo Gallery

An aerial view from the NE shows the three summit cones of Sakura-jima. Kita-dake, the northern cone, is at the right, Naka-dake in the center, and a plume of ash and steam rises from Minami-dake, the historically active southern crater. The city of Kagoshima appears at the upper right across Kagoshima Bay.

Copyrighted photo by Katia and Maurice Krafft, 1981.
An eruption plume from Sakurajima, one of Japan's most active volcanoes, rises above the city of Kagoshima. It is a post-caldera volcano of the Aira caldera at the northern half of Kagoshima Bay. Eruptions began around 13,000 years ago and built an island that joined the Osumi Peninsula during the eruption of 1914. Frequent eruptions have been recorded since the 8th century.

Photo courtesy of Richard Fiske (Smithsonian Institution).
A space shuttle photograph taken on 6 October 1985 shows an ash plume dispersing E from Sakurajima across the Osumi Peninsula to the Pacific Ocean. Sakurajima is near the S rim of the 20-km-wide Aira caldera that encompasses much of the N end of Kagoshima Bay. The caldera formed during an eruption about 22,000 years ago. Kagoshima City is the lighter-colored area across the bay immediately W.

NASA Space shuttle image, 1985 (http://eol.jsc.nasa.gov/).
The 1914 eruption, one of the largest in historical time from Sakura-jima, began with powerful explosions on January 12 from a vent on the west flank, and ten minutes later on the east flank. The initial plinian phase, seen here from Kagoshima City to the west, lasted until the next day, when lava emission began. Lava flows extended the shoreline on the west and east sides, eventually joining Sakura-jima island to the Osumi Peninsula. Damage to croplands and houses on the island from the 1914 eruption was severe.

From the collection of Maurice and Katia Krafft.
Sakurajima entered a period of frequent intermittent moderate explosions in October 1955. Ashfall from the active vent at Minamidake has often deposited ash on Kagoshima, southern Kyushu's largest city located 7 km across the bay. Ash plumes typically reach heights of 1-3 km above the vent. Lahars and ballistic block ejection have intermittently affected populated areas on the island. This September 1981 view shows an ash plume from the W.

Photo by Dick Stoiber, 1981 (Dartmouth College).
An ash plume rises above a restaurant on Sakurajima island in September 1981. Near-continuous periods of explosive eruptions have been occurring since 1955, frequently depositing ash on residential areas. Occasional larger explosions have ejected ballastic blocks that have penetrated concrete roofs of buildings. Villages are located along the island's coast, but most are only 3-5 km from the active Minamidake summit crater.

Photo by Dick Stoiber, 1981 (Dartmouth College).
An ash plume rises above Sakurajima on 9 September 1985, where frequent explosive activity has occurred since October 1955. Eruption plumes typically rise 1-3 km above the vent, with occasional larger explosions. Ashfall commonly occurs over the island and periodically in Kagoshima City, 8 km to the west. Larger explosions eject ballistic blocks that have damaged structures on the island.

Photo by Tom Pierson, 1985 (U.S. Geological Survey).
An incandescent lava dome is visible in the Minamidake crater of Sakurajima in this 9 September 1981 aerial view. Sakurajima has been in near-continuous activity since 1955, with frequent mild-to-moderate explosions that commonly produce ashfall on the island.

Photo by Norm Banks, 1981 (U.S. Geological Survey).
This torii, a Shinto shrine gate, was partially buried by ashfall from the 1914 eruption. The posts and chains surround the gate to protect this historical landmark. Originally 3 m high, the torii is located at the village of Kurokami on the E coast of Sakurajima, 5 km from the summit.

Photo by Norm Banks, 1981 (U.S. Geological Survey).
A plume rises above the Minamidake crater on Sakurajima. Activity at Kitadake, the peak to the right in this view from the SE, ended about 4,850 years ago, after which eruptions took place at Minamidake. Sakurajima is one of Japan's most active volcanoes and is a post-caldera cone in the Aira caldera at the northern half of Kagoshima Bay. Frequent historical eruptions have deposited ash across the bay on Kagoshima, one of Kyushu's largest cities.

Copyrighted photo by Shun Nakano (Japanese Quaternary Volcanoes database, RIODB, http://riodb02.ibase.aist.go.jp/strata/VOL_JP/EN/index.htm and Geol Surv Japan, AIST, http://www.gsj.jp/).
Sakurajima within Aira caldera is producing a gas plume to the NE in this November 2020 Planet Labs satellite image monthly mosaic (N is at the top; this image is approximately 43 km across). The 17 x 23 km caldera formed about 29,000 years ago during the eruption of around 98 km3 of pumice and 300 km3 of pyroclastic flows. In recent times the main epicenter for activity is Sakurajima that has since formed in Kagoshima Bay and is seen here with a weak gas plume dispersing NE to E.

Satellite image courtesy of Planet Labs Inc., 2020 (https://www.planet.com/).
GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Smithsonian Sample Collections Database

The following 35 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number Sample Description Lava Source Collection Date
NMNH 101503 Unidentified -- --
NMNH 101504 Unidentified -- --
NMNH 101505 Unidentified -- --
NMNH 106753-00 Osumilite -- --
NMNH 112953 Andesite -- --
NMNH 112953 Andesite -- --
NMNH 112954 Andesite -- --
NMNH 112954 Andesite -- --
NMNH 112954 Andesite -- --
NMNH 112955 Andesite MINAMI-DAKE CONE --
NMNH 112955 Andesite MINAMI-DAKE CONE --
NMNH 112956 Andesite -- --
NMNH 112956 Andesite -- --
NMNH 112957 Andesite -- --
NMNH 112957 Andesite -- --
NMNH 112958 Andesite -- --
NMNH 112958 Andesite -- --
NMNH 112958-1 Andesite -- --
NMNH 112959 Andesite KITA-DAKE CONE --
NMNH 112959 Andesite KITA-DAKE CONE --
NMNH 125022-00 Osumilite -- --
NMNH 88259 Volcanic Lapilli -- --
NMNH 88260 Volcanic Lapilli -- --
NMNH 88261 Pumice -- --
NMNH 88262 Volcanic Shale -- --
NMNH 88263 Pyroxene Andesite -- --
NMNH 88264 Lava -- --
NMNH 88265 Pyroxene Andesite -- --
NMNH 88266 Volcanic Bomb -- --
NMNH 88267 Volcanic Breccia -- --
NMNH 88268 Andesite -- --
NMNH 88658 Volcanic Bomb -- --
NMNH 88659 Shale -- --
NMNH 88661 Volcanic Ball -- --
NMNH 88661 Volcanic Bomb -- --
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