Report for Whakaari/White Island
On 28 June GeoNet reported that activity at Whakaari/White Island had remained at a low level. Observations during an overflight the week before showed that fumaroles active on the crater floor did not contain ash. Gas emission rates had decreased compared to the last observations from mid-May, and the temperature of fumarolic emissions was low at 170 degrees Celsius on 22 June. Visual observations and data collected during the flight, coupled with data from automatically collected monitoring instruments, indicated almost no changes at the volcano in the previous few weeks. The Volcanic Alert Level remained at 1 and the Aviation Color Code remained at Green.
Report for Ruapehu
On 28 June GeoNet reported that it had been 10 days since the last notable tremor at Ruapehu and the level remained weak. Lake water temperatures declined to 21 degrees Celsius on 14 June from a high of 40 degrees Celsius recorded in early May; temperatures had increased to 25 degrees Celsius during the previous two weeks. Gas emissions continued to fluctuate based on data collected during overflights and were about 10% less on 23 June than on 13 May, though the sulfur dioxide rate during 24-25 June was comparable to those recorded in mid-May, based on gas measuring equipment recently installed at the volcano. The emission, water temperature and seismic data together indicated continuing moderate levels of unrest. The Volcanic Alert Level remained at 2 (on a scale from 0-5) and the Aviation Color Code remained at Yellow.
Report for Krakatau
PVMBG reported that at 1712 on 25 June an eruptive event at Anak Krakatau produced a dense black ash plume that rose 400 m above the summit and slowly drifted SW. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay at least 5 km away from the crater.
Report for Merapi
BPPTKG reported that the eruption at Merapi continued during 17-23 June. The heights and morphologies of the SW lava dome and the central lava dome were unchanged from the previous week, and seismicity remained at high levels. As many as 70 lava avalanches traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 1.8 km. Seismicity remained high. 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.
Report for Semeru
PVMBG reported that the eruption at Semeru continued during 22-28 June. Weather clouds prevented visual observations on most days; at 0628 on 24 June an eruptive event produced an ash plume that rose 700 m and drifted SW. The Alert Level remained at 3 (on a scale of 1-4). The public was warned to stay at least 5 km away from the summit, and 500 m from Kobokan drainages within 17 km of the summit, along with other drainages originating on Semeru, including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.
Report for Lewotolok
PVMBG reported that the eruption at Lewotolok continued during 22-28 June. An eruptive event was recorded at 2235 on 24 June by the seismic network, though the event was not visually observed. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater, and 3.5 and 4 km away from the crater on the SE flank and E and NE flanks, respectively.
Report for Ruang
An increased number of deep volcanic earthquakes at Ruang in April prompted PVMBG to raise the Alert Level to 2 (on a scale of 1-4). A total of 232 deep volcanic earthquakes were recorded by the seismic network during 1 April-22 June, with just over half of them occurring in early to mid-April. No data was recorded from 18 April through 11 May due to technical difficulties. The network recorded 6-20 events during 11-31 May and just 1-2 events during 1-21 June. PVMBG lowered the Alert Level to 1 on 23 June.
Report for Dukono
Based on satellite and wind model data, the Darwin VAAC reported that during 22-25 and 27 June ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted N, NW, and W. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone.
Report for Bulusan
PHIVOLCS reported that unrest continued at Bulusan during 22-28 June. Emissions rose 100-400 m above the summit and drifted NW and W; cloudy weather prevented views of the volcano on 26 June. Sulfur dioxide emissions were 559-751 tonnes per day during 22-26 June. The seismic network recorded 7-65 daily volcanic earthquakes. A small-volume lahar was detected during a thunderstorm, beginning at 1904 on 26 June and lasting for 54 minutes based on seismic and infrasound data. Narrow, channel-confined lahar deposits were seen later along the Calang Creek on the SW flank, in the Cogon barangay. The Alert Level remained at 1 (on a scale of 0-5) and PHIVOLCS reminded the public not to enter the 4-km-radius Permanent Danger Zone (PDZ) nor the 2 km Extended Danger Zone (EDZ) on the SE flank.
Report for Suwanosejima
JMA reported that the eruption at Suwanosejima's Ontake Crater continued during 20-27 June. Emissions rose as high as 2 km above the crater rim and material was ejected as far as 200 m from the vent. The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater.
Report for Aira
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.
Report for Ontakesan
Inflation and increased seismicity were detected at Ontakesan in February, causing JMA to raise the Alert Level. Inflation ceased in late February and deformation rates had stabilized. Seismicity continued to fluctuate, but decreased in mid-March and volcanic tremor ceased on 19 March. No changes in emissions were observed on 4 June. JMA lowered the Alert Level for Ontakesan to 1 (on a scale of 1-5) on 23 June.
Report for Chikurachki
KVERT reported that a thermal anomaly over Chikurachki was identified on 21 June and an explosive eruption occurred on 24 June. Explosions recorded during 0730-2100 on 24 June (local time) produced ash plumes that rose to 4.5 km (14,800 ft) a.s.l. A 14 x 30 km ash cloud was visible in satellite images at 0850 drifting 25 km SE, prompting KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale). A VONA issued at 1445 on 25 June (local time) stated that only gas-and-steam emissions were rising from the volcano and that the Aviation Color Code was lowered to Yellow. The ash cloud from the explosive phase had drifted about 790 km SE. Satellite images on 26 June indicated no additional explosions; gas-and-steam emissions persisted. At 1624 (local time) the Aviation Color Code was lowered to Green.
Report for Ebeko
KVERT reported that moderate activity at Ebeko continued according to volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E. Explosions generated ash plumes that rose up to 2.5 km (8,200 ft) a.s.l. and drifted S, SE, and NE during 18 and 22-23 June. A thermal anomaly over the volcano was identified in satellite images on 22 June. At 1510 local time on 24 June an ash plume was observed drifting 5 km SE at an altitude of 2.5 km (8,200 ft) a.s.l., prompting KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale).
Report for Karymsky
KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 17 and 19-23 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.
Report for Bezymianny
KVERT reported that a thermal anomaly over Bezymianny was identified in satellite images during 17-26 June. The Alert Level was lowered to Yellow (the second lowest level on a four-color scale) on 26 June. Dates are based on UTC times; specific events are in local time where noted.
Report for Sheveluch
KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 17-23 June and the eruption characterized by explosions, hot avalanches, and lava-dome extrusion continued. Webcam images recorded explosions on 19 and 21 June that sent ash plumes to 7 and 5 km (23,000 and 16,400 ft) a.s.l., respectively. The ash plumes were visible in satellite images drifting 255 km ENE and 70 km SW during 19-20 and 21 June. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.
Report for Semisopochnoi
AVO reported that low-level eruptive activity at Semisopochnoi's North Cerberus cone continued during 21-27 June. Periods of low-amplitude tremor and a few small low-frequency earthquakes were recorded by the seismic network. Weather clouds often prevented satellite and webcam views; sulfur dioxide emissions were detected in satellite images during 23-24 June and a robust steam plume was visible in webcam images during 25-26 June. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.
Report for Great Sitkin
AVO reported that the eruption at Great Sitkin continued during 21-28 June. Elevated surface temperatures were identified in satellite images during 26-27 June; weather clouds obscured satellite and webcam views on the other days. Seismicity was low. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Report for Pavlof
AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 21-28 June, and seismic tremor persisted. Daily elevated surface temperatures identified in satellite images were consistent with the continuing effusion of short (615 m or less) lava flows. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange.
Report for Kilauea
HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 22-28 June, entering the lava lake and flowing onto the crater floor. The lake remained active all week, and nearly continuous breakouts occurred along the margins. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.
Report for San Cristobal
According to a news article, INETER reported that at 0751 on 26 June a moderate explosion at San Cristóbal produced a gas-and-ash plume that rose 1.5 km above the crater rim and drifted WSW. A minor amount of ash fell in the communities of La Grecias 3 and Las Grecias 4 (12 km WSW), and the city of El Viejo (18 km WSW). RSAM data spiked during the explosion and then returned to normal levels afterwards.