Smithsonian / USGS Weekly Volcanic Activity Report

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday and averaging 16 reported volcanoes, this is not a comprehensive list of all eruptions this week, but rather a summary of activity that meet criteria discussed in the "Criteria and Disclaimers" section below.

Volcanic activity reported here is preliminary and subject to change. Carefully reviewed, detailed narratives over longer time periods are published as reports of the Bulletin of the Global Volcanism Network available through volcano profile pages.

Smithsonian / USGS Weekly Volcanic Activity Report for the week of 3 July-9 July 2024
Name	Country	Volcanic Province	Eruption Start Date	Report Status
Cleveland	United States	Aleutian Ridge Volcanic Arc	—	New
Etna	Italy	Sicily Volcanic Province	2022 Nov 27	New
Home Reef	Tonga	Tofua Volcanic Arc	—	New
Karymsky	Russia	Eastern Kamchatka Volcanic Arc	2024 Jun 20	New
Stromboli	Italy	Aeolian Volcanic Arc	1934 Feb 2	New
Aira	Japan	Ryukyu Volcanic Arc	2017 Mar 25	Continuing
Dukono	Indonesia	Halmahera Volcanic Arc	1933 Aug 13	Continuing
Ebeko	Russia	Kuril Volcanic Arc	2022 Jun 11	Continuing
Great Sitkin	United States	Aleutian Ridge Volcanic Arc	2021 May 25	Continuing
Ibu	Indonesia	Halmahera Volcanic Arc	2008 Apr 5	Continuing
Lewotobi	Indonesia	Sunda Volcanic Arc	2023 Dec 23	Continuing
Lewotolok	Indonesia	Sunda Volcanic Arc	—	Continuing
Marapi	Indonesia	Sunda Volcanic Arc	2023 Dec 3	Continuing
Merapi	Indonesia	Sunda Volcanic Arc	2020 Dec 31	Continuing
Nyamulagira	DR Congo	Albertine Rift Volcanic Province	2018 Apr 18	Continuing
Nyiragongo	DR Congo	Albertine Rift Volcanic Province	2002 May 17 (?)	Continuing
Purace	Colombia	Northern Andean Volcanic Arc	—	Continuing
Rincon de la Vieja	Costa Rica	Central America Volcanic Arc	2021 Jun 28	Continuing
Sabancaya	Peru	Central Andean Volcanic Arc	2016 Nov 6	Continuing
Semeru	Indonesia	Sunda Volcanic Arc	2017 Jun 6	Continuing
Sheveluch	Russia	Eastern Kamchatka Volcanic Arc	1999 Aug 15	Continuing
Suwanosejima	Japan	Ryukyu Volcanic Arc	2004 Oct 23	Continuing

All times are local unless otherwise stated.

Cleveland (United States) | 3 July-9 July 2024 | New Activity / Unrest Cite this Report

Cleveland
Aleutian Ridge Volcanic Arc

AVO reported that sulfur dioxide emissions were detected by local gas monitoring sensors at Cleveland starting on 21 June. The emission rate increased during 24-30 June and then declined to background levels on 1 July. Although sulfur dioxide emissions had declined, vigorous steaming and moderately elevated surface temperatures at the summit were detected in satellite images the following days. On 5 July the Volcano Alert Level was raised to Advisory (the second lowest level on a four-level scale) and the Aviation Color Code was raised to Yellow (the second lowest color on a four-color scale). During 6-8 July a few small earthquakes were detected, steaming from the summit was observed, and elevated surface temperatures were characterized as weak. On 8 July the Volcano Alert Level was lowered to Normal and the Aviation Color Code was lowered to Green.

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Etna (Italy) | 3 July-9 July 2024 | New Activity / Unrest Cite this Report

Etna
Sicily Volcanic Province

Sezione di Catania - Osservatorio Etneo (INGV) reported that an eruption at Etna continued during 3-9 July, with activity intensifying on 4 July and producing substantial ashfall in areas downwind during 4-7 July. Strombolian activity at Voragine Crater intensified during 2-3 July and lava continued to flow into Bocca Nuova Crater. During the evening of 3 July Dipartimento della Protezione Civile raised the Alert Level to Yellow (the second lowest level on a four-level scale). Strombolian activity at Voragine notably intensified during the morning of 4 July and tremor amplitude further increased around 1420. Two lava flows from two vents located on the SE and NW sides of the growing scoria cone continued to flow into the Bocca Nuova. Bombs and scoria were ejected hundreds of meters high. The Strombolian activity changed to tall lava fountaining at 1815 and produced ash-and-gas plumes that rose to about 4.5 km a.s.l., or over 1.1 km above the summit, and drifted SE. Notable ashfall was reported in several areas downwind as far as Catania (29 km SSE). The lava fountaining gradually decreased through the night and ceased at around 0350 on 5 July; about an hour of Strombolian activity followed. Ash-and-gas emissions continued to rise to the same height as the previous day and drifted SE. Significant ashfall was reported in areas downwind and beyond Syracuse, 60-80 km SSE. According to a news article the airport in Catania closed due to ash on the runways; operations resumed by 1500, though some flight restrictions were in place.

The amplitude of volcanic tremor fluctuated between medium and high levels. Strombolian activity resumed during the afternoon on 6 July. The activity intensified at around 0000 on 7 July and changed to lava fountaining by around 0400. Ash emissions rose about 9 km a.s.l. (about 5 km above the summit) and drifted ESE, causing significant ashfall to the E, especially in the area between Zafferana Etnea (10 km SE) and Giarre (17 km ESE). At around 0850 lava overflowed the NW rim of Bocca Nuova Crater and traveled just over 500 m, stopping at around 3,000 m elevation. Sporadic ash emissions at Southeast Crater were observed. The lava fountaining gradually weakened and ceased at around 1000 and was followed by Strombolian activity that also gradually weakened and then ceased after about an hour. A more notable ash emission from Southeast Crater occurred at 1141 and rapidly dissipated. By 1228 minor ash emissions continued to occur and lava continued to flow from the summit craters.

Sources: Sezione di Catania - Osservatorio Etneo (INGV), Dipartimento della Protezione Civile, Reuters, Euronews

Home Reef (Tonga) | 3 July-9 July 2024 | New Activity / Unrest Cite this Report

Home Reef
Tofua Volcanic Arc

The Tonga Geological Services reported that an eruption at Home Reef was ongoing during 3-9 July based on the detection of thermal anomalies. Daily thermal anomalies were identified in infrared satellite images, though the number and intensity of the anomalies were variable. A satellite image acquired at 0720 on 4 July showed a small ash cloud drifting N at 2 km a.s.l. A plume of discolored water originating along the central part of the E coast, at the N end of the new lava flow, was visible in a 5 July satellite image drifting SE. The Maritime Alert Level remained at Orange (the second highest level on a four-color scale) and mariners were advised to stay 4 km away from the island, the Aviation Color Code remained at Yellow (the second lowest color on a four-color scale), and the Alert level for residents of Vava’u and Ha’apai remained at Green (the lowest color on a four-color scale).

Source: Tonga Geological Services, Government of Tonga

Karymsky (Russia) | 3 July-9 July 2024 | New Activity / Unrest Cite this Report

Karymsky
Eastern Kamchatka Volcanic Arc

KVERT reported that explosive activity at Karymsky that started on 20 June possibly continued through 4 July; weather clouds obscured views during the week. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Stromboli (Italy) | 3 July-9 July 2024 | New Activity / Unrest Cite this Report

Stromboli
Aeolian Volcanic Arc

INGV reported a period of intense activity at Stromboli that included spattering, lava overflows from a series of vents along the Sciara del Fuoco, pyroclastic flows, and debris avalanches. During 1-3 July low- to medium-intensity explosive activity at two vents in Area N (one at N1 and one at N2) and in sector S2 (Area C-S) ejected coarse material (bombs and lapilli) less than 150 m above the vents. Explosive activity at S2 decreased and then stopped on 3 July.

A gradual increase in the amplitude of seismic tremor from medium to high levels began at around 1730 on 3 July. A sudden increase in amplitude to very high levels occurred at about 1820 and the amplitude peaked 20 minutes later, concurrent with stronger spattering in Area N at 1835. A series of about 20 collapses at the cone began at around 1845, producing avalanches of incandescent material that rapidly descended the Sciara del Fuoco, reached the coastline, and spread out over the sea. The activity produced ash clouds that drifted over the S and E parts of the island. Spattering and explosive activity followed, and at 1902 lava overflowed Area N, descended the upper part of the Sciara del Fuoco, and produced block avalanches that rolled down the flank. At about 1905 tremor amplitude rapidly decreased but remained at high levels. Lava flows continued to be fed through the night, reaching 550-600 m elevation, but ceased in the morning and cooled.

A period of almost continuous landslides occurred at N2 during the early afternoon of 4 July. At around 1410 on 4 July a lava flow from a new vent at 700 m elevation in Area N descended the Sciara del Fuoco along with a pyroclastic flow. At 1714 the lava branched at around 600-650 m elevation and traveled parallel to the first, reaching the coastline at 1747. At 1818 a new vent with a high lava effusion rate opened at around 510 m elevation. Both the lava flow and a simultaneously generated pyroclastic flow rapidly descended the Sciara del Fuoco to the coastline, where the pyroclastic flow spread over the sea for several hundred meters. An ash plume rose 2 km a.s.l. Numerous additional pyroclastic flows descended the Sciara del Fuoco; the most notable one occurred at 2010 and again spread several hundred meters over the water. At 2000 the Dipartimento della Protezione Civile raised the Alert Level to Red (the highest level on a four-level scale).

Lava flowed down to the coast on 5 July and produced steam-and-ash plumes where it contacted the sea. Tremor amplitude fluctuated between high and very high values and then decreased to average values by 0600. A sequence of pyroclastic flows at 1219, 1227, 1230, and 1233 quickly descended the flank and reached the sea; another descended the Sciara del Fuoco at 1431. By 1536 fresh lava supply to the flow had decreased, and material breaking from the flow front was rolling down the flank. Effusive activity increased at around 2055 based on field observations and a lava flow descended the flank, stopping a few tens of meters from the coastline; effusion again stopped.

Lava effusion restarted by 1321 on 6 July from a vent at 485 m elevation and produced a lava flow that traveled about 285 m. Blocks detached from the flow front and rolled down the flank to the sea. Effusive activity intensified during 6-7 July. Lava from vents at 510 m and 485 m elevation converged and flowed down the flank to the coast, creating a small lava delta and producing ash-and-steam plumes. Incandescent lava blocks rolled down the flanks and caused small phreatic explosions when they reached the sea.

Sources: Sezione di Catania - Osservatorio Etneo (INGV), Dipartimento della Protezione Civile

Aira (Japan) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Aira
Ryukyu Volcanic Arc

JMA reported ongoing eruptive activity at Minamidake Crater (Aira Caldera’s Sakurajima volcano) during 1-8 July. Nighttime crater incandescence was visible. An explosion at 2151 on 2 July produced an ash plume that rose 1.7 km above the crater rim and drifted NE, and also ejected large blocks 800-1,100 m from the vent. An explosion at 2208 on 4 July produced an ash plume that rose 900 m above the crater rim and drifted NE, with large blocks ejected 500-700 m from the vent. An eruptive event at 0513 on 8 July produced an ash plume that rose 2.3 km above the crater rim and drifted NE. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters.

Source: Japan Meteorological Agency (JMA)

Dukono (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Dukono
Halmahera Volcanic Arc

PVMBG reported that the eruption at Dukono was ongoing during 3-10 July. Daily gray-and-white ash plumes that were sometimes dense rose 100-1,200 m above the summit and drifted W, NE, and E. The ash plumes were white, gray, and black on 9 July. The Alert Level remained at Level 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Ebeko (Russia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Ebeko
Kuril Volcanic Arc

KVERT reported that moderate explosive activity was ongoing at Ebeko during 27 June-4 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 28-30 June and 4 July generated ash plumes that rose as high as 4 km (13,100 ft) a.s.l. and drifted N, NE, and SE. Thermal anomalies were identified in satellite images during 28-29 June; on other days either no activity was observed or weather conditions prevented views. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Great Sitkin (United States) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Great Sitkin
Aleutian Ridge Volcanic Arc

AVO reported that slow lava effusion in Great Sitkin’s summit crater was last confirmed in a 7 July radar image; effusion likely continued during 8-9 July. Seismicity was low during 3-9 July with few daily small earthquakes recorded by the seismic network. Weather clouds mostly obscured satellite and webcam views during most of the week. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)

Ibu (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Ibu
Halmahera Volcanic Arc

PVMBG reported that activity at Ibu continued during 3-9 July. Daily white-and-gray or white, gray, and black ash plumes rose as high as 5 km above the summit and drifted in multiple directions. The ash plumes rose 3-4 km above the summit during 3-5 July and as high as 1.2 km during 6-9 July. The Alert Level remained at 3 (the second highest level on a four-level scale) and the public was advised to stay 4 km away from the active crater and 5 km away from the N crater wall opening.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Lewotobi (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Lewotobi
Sunda Volcanic Arc

PVMBG reported that eruptive activity at Lewotobi’s Laki-laki volcano continued during 3-9 July. Multiple daily gray or white-and-gray ash plumes that were sometimes dense rose 50-1,000 m above the summit and drifted SW, W, and NW. According to a news article a series of three black-to-gray ash plumes with increasing intensity occurred on 3 July; the first two plumes rose 700 m and 800 m, and the third, recorded at 1356, rose 3 km. The plumes drifted E, NW, W, and SW. The Alert Level remained at 3 (the second highest level on a scale of 1-4) and the public was warned to stay outside of the exclusion zone, defined as a 3-km radius around both Laki-laki and Perempuan craters, 4 km to the NNW and SSE of Laki-laki.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Antara News

Lewotolok (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Lewotolok
Sunda Volcanic Arc

PVMBG reported that the eruption at Lewotolok continued during 3-9 July. White-and-gray ash plumes rose as high as 300 m above the summit and drifted W and NW during 3-4 July. Daily white steam-and-gas emissions rose as high as 400 m above the summit and drifted NW and W on the other days during the week. Summit incandescence was visible in webcam images during the week; incandescent material being ejected above the summit was visible in a 6 July image. The Alert Level remained at 2 (on a scale of 1-4) and the public was warned to stay 2 km away from the vent and 2.5 km away from the vent on the S, SE, and W flanks.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Marapi (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Marapi
Sunda Volcanic Arc

PVMBG reported that eruptive activity at Marapi (on Sumatra) was ongoing during 3-9 July. White gas-and-steam plumes rose 200-800 m above the summit and drifted in multiple directions during 4-5 and 8 July. Emissions were not observed on the other days. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 3 km away from the active crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Merapi (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Merapi
Sunda Volcanic Arc

BPPTKG reported that the eruption at Merapi (on Java) continued during 28 June-4 July. Seismicity had increased compared to the previous week. The SW lava dome produced 94 lava avalanches that traveled as far as 1.8 km down the upper part of the Bebeng drainage on the SW flank. One pyroclastic flow descended the SW flank as far as 1 km. Morphological changes to the SW lava dome were due to continuing effusion and collapses of material. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-7 km away from the summit, based on location.

Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)

Nyamulagira (DR Congo) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Nyamulagira
Albertine Rift Volcanic Province

A 5 July satellite image showed an irregularly shaped thermal anomaly on the NE-central part of Nyamuragira’s crater floor. Weather clouds obscured parts of the crater.

Source: Copernicus

Nyiragongo (DR Congo) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Nyiragongo
Albertine Rift Volcanic Province

A 5 July satellite image showed a dark elliptical area of lava on Nyiragongo’s crater floor. Gas-and-steam plumes appeared to be rising from two central vents. Thermal anomalies identified in SWIR images corresponded to the location of the lava area along with a small brighter area at the center.

Source: Copernicus

Purace (Colombia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Purace
Northern Andean Volcanic Arc

Observatorio Vulcanológico y Sismológico de Popayán, Servicio Geologico Colombiano (SGC) lowered the Alert Level for Puracé to Yellow (the second lowest level on a four-color scale) on 5 July noting that activity had declined and stabilized. Seismicity had increased around 24 April, peaked during 30 May-6 June with the highest daily number of earthquakes recorded since instrumental monitoring began, and then declined to pre-unrest levels during the past few weeks. The magnitudes of the earthquakes decreased to less than M1. Sulfur dioxide emissions also decreased during the previous few weeks and deformation rates were similar to those detected before the period of unrest.

Source: Servicio Geológico Colombiano (SGC)

Rincon de la Vieja (Costa Rica) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Rincon de la Vieja
Central America Volcanic Arc

OVSICORI-UNA reported that small phreatic eruptions at Rincón de la Vieja were recorded at 1140 and 1824 on 9 July. The second event produced a steam-and-gas plume that rose 1 km above the crater rim. A significant increase in tremor amplitude was detected in the afternoon of 9 July and remained high and continuous at least through the morning of 10 July.

Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA)

Sabancaya (Peru) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Sabancaya
Central Andean Volcanic Arc

Instituto Geofísico del Perú (IGP) reported that the eruption at Sabancaya continued at moderate levels during 1-7 July with a daily average of 40 explosions. Gas-and-ash plumes rose as high as 2.9 km above the summit and drifted less than 10 km E and SE. Thermal anomalies over the lava dome in the summit crater were identified in satellite data. Slight inflation was detected near the Hualca Hualca sector (4 km N). Sulfur dioxide emissions were at moderate levels, averaging 497 tons per day. The Alert Level remained at Orange (the third level on a four-color scale) and the public was warned to stay outside of a 12 km radius.

Source: Instituto Geofísico del Perú (IGP)

Semeru (Indonesia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Semeru
Sunda Volcanic Arc

PVMBG reported that eruptive activity continued at Semeru during 3-9 July. White-and-gray ash plumes that were sometimes dense rose 300-1,000 m above the summit and drifted in multiple directions. Daily eruptive events, sometimes several per day, were recorded by the seismic network, though plumes were not always visually confirmed; emissions were not observed during 4-5 July. Incandescence at the summit and incandescent avalanches on the SE flank were occasionally observed in webcam images. The Alert Level remained at 3 (the third highest level on a scale of 1-4). The public was warned to stay at least 5 km away from the summit in all directions, 13 km from the summit to the SE, 500 m from the banks of the Kobokan drainage as far as 17 km from the summit, and to avoid other drainages including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Sheveluch (Russia) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Sheveluch
Eastern Kamchatka Volcanic Arc

KVERT reported that thermal anomalies over both the “300 years of RAS” dome and the older lava dome at Sheveluch were identified in satellite images during 28 June and 3-4 July. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Suwanosejima (Japan) | 3 July-9 July 2024 | Continuing ActivityCite this Report

Suwanosejima
Ryukyu Volcanic Arc

JMA reported that eruptive activity at Suwanosejima's Ontake Crater continued during 1-8 July and produced volcanic plumes that rose as high as 500 m above the crater rim. Crater incandescence was observed nightly in webcam images. No explosions were recorded. The Alert Level remained at 2 (on a 5-level scale) and the public was warned to stay at least 1.5 km away from the crater.

Source: Japan Meteorological Agency (JMA)

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Criteria & Disclaimers

Criteria

The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:

- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.

Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.

It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.

Disclaimers

1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are cover longer time periods and are more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.

2. Rapidly developing events lead to coverage that is often fragmentary. Volcanoes, their eruptions, and their plumes and associated atmospheric effects are complex phenomena that may require months to years of data analysis in order to create a comprehensive summary and interpretation of events.

3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.

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