Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 27 July – 2 August 2022

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 21-28 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose up to 4 km (13,100 ft) a.s.l. and drifted in multiple directions.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin continued during 26 July-2 August. Weather clouds obscured satellite and webcam views during most of the week, though satellite radar data confirmed ongoing effusion; flows thickened but did not advance. Seismicity was low, and occasional local earthquakes were recorded. Steam emissions were visible in satellite and webcam images during 29-30 July.

Grimsvotn – Iceland : The Icelandic Meteorological Office (IMO) reported that increased seismicity, characterized by several earthquakes with magnitudes over 1, began at Grímsvötn during the afternoon of 2 August and continued through the afternoon of 3 August. The largest event was a M 3.6 detected at 1424.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 21-23 and 27-28 July. Ash plumes were identified in satellite images drifting 46 km ESE on 27 July.

Kilauea – Hawaiian Islands (USA): HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 26 July-2 August, entering the lava lake and flowing onto the crater floor. Minor ooze-outs along the margins of the crater floor were visible during 1-2 August. The lake level remained at the bounding levees.

Krakatau – Sunda Strait : PVMBG reported that the eruption at Anak Krakatau continued during 27 July-2 August. Several eruptive events occurred on 2 August (at 1549, 1835, 1906, 2249, and 2319) and on 3 August (at 0034, 0115, and 1540), sometimes producing black ash plumes that rose as high as 1.5 km above the summit and drifted NE and SW.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 22-28 July. Based on photo analyses, the volumes of both the SW and central lava domes had increased, with recent volume estimates of 1.67 and 2.79 million cubic meters, respectively. Seismicity remained at high levels. As many as 47 lava avalanches traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 1.8 km.

Pavlof – Alaska Peninsula, Alaska: AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 26 July-2 August. Daily elevated surface temperatures were identified in satellite images. Seismic tremor persisted and multiple daily explosions were detected in local and regional seismic and infrasound data. The explosions likely produced minor ash emissions that rose no higher than 3 km (10,000 ft) a.s.l., though cloud cover prevented confirmation on most days. Ash emissions were visible in webcam images during 27-28 July. Sulfur dioxide gas emissions were visible on 26 July and team emissions were noted during 30-31 July.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 27 July-2 August. Eruptive events recorded at 0637 on 27 July, 0926 on 29 July, 0825 on 31 July, 0757 on 1 August, 0555 on 2 August, and 0810 on 3 August produced ash plumes that rose 500-700 m above the summit and drifted SW.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch was characterized by explosions, hot avalanches, and lava-dome extrusion during 21-28 July. A daily thermal anomaly was identified in satellite images, and ash plumes were visible drifting 74 km SSW and SE on 22 and 24 July.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 25 July-2 August. One explosion produced an eruption plume that rose more than 1.8 km above the crater rim and caused ashfall in Toshima village (3.5 km SSW).

Yufu-Tsurumi – Kyushu (Japan) : JMA lowered the Alert Level for Yufu-Tsurumi to 1 (on a scale of 1-5) on 27 July, noting that seismicity had decreased after the 8 July earthquake swarm; no volcanic earthquakes were recorded on 9 July and afterwards.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 27 July – 2 August 2022

Aira – Kyushu (Japan) : 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.

Askja – Iceland : On 27 July IMO stated that uplift at Askja began in August 2021 and since then had totaled 35 cm, centered in the W part of Askja lake. The uplift was rapid, compared to similar volcanoes around the world, and likely caused by a magmatic intrusion at an estimated depth of 2 km. Seismicity remained low.

Ioto – Volcano Islands : Satellite images of Ioto (Iwo-jima) acquired on 15 July showed a darker area in the water along the SE coast, possibly above or near the 2001 vent, and a plume of discolored water drifting NE. Video taken on or around 25 July showed a white plume rising from the same area. Satellite images during 30-31 July showed small rounded gray zones at the water surface.

Krysuvik-Trolladyngja – Reykjanes Peninsula : Icelandic Meteorological Office (IMO) reported that an intense earthquake swarm began around noon on 30 July within the Krýsuvík-Trölladyngja volcanic system. The earthquakes were located in an area just NE of lava field in Geldingadalir, along the dike intrusion that preceded the March-September 2021 eruption. The swarm was likely caused by a magmatic intrusion at depths of 5-7 km. Earthquakes were reportedly felt in SW Iceland, in Reykjanesbær, Grindavík, the Capital region, and as far as Borgarnes. Several earthquakes were above M 3; a larger M 4 event was recorded at 1403. IMO raised the Aviation Color Code to Yellow, based on above-background seismic levels. At around 1800 the epicenters shallowed to depths of 2-5 km. By 1527 on 31 July almost 3,000 earthquakes had been detected, with four of the events larger than an M 4. A larger M 5.4 earthquake was detected at 1748. IMO reported at 1749 on 2 August that deformation models indicated magma around 1 km below the surface. The intrusion rate was close to double that recorded prior to the 2021 eruption, though by the reporting time the intrusion and seismicity rates had slowed. IMO noted that a similar pattern of events took place prior to the last eruption and stated that the likelihood of an eruption had increased. An effusive eruption began at 1315 on 3 August in Meradalir, near the border of the previous flow field N of Fagradalsfjall. Webcam video showed lava fountains rising along a 300-m-long fissure.

Kuchinoerabujima – Ryukyu Islands (Japan) : JMA reported that the number of volcanic earthquakes with hypocenters near Kuchinoerabujima’s crater began increasing around 1000 on 30 July and remained elevated. The Alert level was raised to 2 (on a scale of 1-5) on 31 July. Around 40 volcanic earthquakes were recorded by 1500 on 1 August. JMA noted that daily emissions of sulfur dioxide gas remained low, with a rate less than 50 tons per day. No deformation was detected.

Raung – Eastern Java : According to PVMBG an eruption at Raung at 1719 on 27 July produced a gray ash plume that rose 1-1.5 km above the summit and drifted W and NW. On 28 July a thermal anomaly in the crater was identified in satellite images and data from the GPS network indicated inflation, likely from an intrusion of magma. Seismicity on 29 July was dominated by continuous tremor. The Alert Level was raised to 2 (on a scale of 1-4) that same day, and the public was warned to stay 3 km away from the crater.

Volcanos

Roundup of Global Volcanic Activity – Continuing Activity for the week 20 July – 26 July 2022

Chiles-Cerro Negro – Colombia-Ecuador : Instituto Geofísico de la Escuela Politécnica Nacional (IGEPN) and the Observatorio Vulcanológico y Sismológico de Pasto del Servicio Geológico Colombiano (SGC OVSP) both monitor the Cerro Negro de Mayasquer and Chiles volcanoes, called the Chiles-Cerro Negro volcanic complex (CCNVC), and both issued reports on the seismic swarm that began on 27 May. This seismicity was mainly characterized by VT earthquakes, typically indicating rock fracturing events. The swarm continued during 12-26 July, though the number and size of events were variable. The earthquakes were located along a fracture zone on and as far as 3.5 km S of Chiles volcano, at depths less than 6 km. The number of long-period (LP) and very-long-period (VLP) earthquakes, low-energy events indicating fluid movement, had increased in the previous two weeks; 60 of such events were recorded on 17 July, the highest daily number of events recorded since the beginning of permanent monitoring in November 2013, and 64 were recorded in 20 July. During 12-23 July a total of 43 earthquakes had local magnitudes greater than 2; four of those events, a M 3.3 recorded at 1038 on 16 July, a M 2.8 at 0816 on 22 July, a M 3.5 at 1746 on 22 July, and a M 3 at 2247 on 23 July were all felt in surrounding areas, including in the municipality of Cumbbal, in the department of Nariño. At 0833 on 25 July a M 5.6 was recorded, with a hypocenter located about 10 km S of Tufiño (Carchi province, Ecuador). Building damage was reported in San Gabriel, Tulcán, and El Ángel (Ecuador) and in the Municipalities of Túquerres and Cumbal (Colombia). Data from continuous GPS geodetic bases located in the vicinity of the Chiles volcano showed a trend of inflation at a rate of approximately 28 mm/year that has been recorded since 2016 (the beginning of deformation monitoring) through the end of 2020, when the deformation stabilized. Neither inflation nor deflation was detected during the beginning of 2020 or in 2021. Inflation was again detected in March, at a rate of 32 mm/year. The rate of inflation notably increased during April-July to an average of 106 mm/year, occurring in at least two deformation zones, one S of Chiles and another in the Potrerillos caldera.

Dukono – Halmahera : PVMBG reported that during 19-25 July almost daily white-and-gray ash plumes from Dukono rose as high as 300 m above the summit and drifted N, E, and W.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin continued during 19-26 July. Elevated surface temperatures were identified in satellite images during 19-20 July; weather clouds obscured satellite and webcam views during most of the rest of the week. Seismicity was low, and occasional local earthquakes were recorded. Steam emissions were visible in satellite images during 25-26 July.

Ibu – Halmahera : PVMBG reported that the eruption at Ibu continued during 21-25 July. Gray-and-white ash plumes of variable densities generally rose as high as 2 km above the summit and drifted in multiple directions.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 14-21 July. Ash plumes were identified in satellite images drifting 170 km S and SE on 15 July.

Kilauea – Hawaiian Islands (USA) : HVO stated that by 19 July about 98 million cubic meters of lava had been erupted from a vent in the lower W wall of at Kilauea’s Halema`uma`u Crater since the current eruption began on 29 September 2021, raising the crater floor by 133 m. Lava continued to effuse from the vent during 19-26 July, entering the lava lake and flowing onto the crater floor. The lake level remained at the bounding levees, though lava oozed from the lake margins on most days. The sulfur dioxide emission rate was approximately 1,300 tons/day on 21 July.

Krakatau – Sunda Strait : The Darwin VAAC reported that during 20 and 22-24 July ash plumes from Anak Krakatau rose to 2.6-3 km (9,000-10,000 ft) a.s.l. and drifted SW, WSW, and W based on satellite and webcam images as well as weather models.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 20-26 July. Daily white or white-and-gray emissions rose as high as 500 m above the summit and drifted in multiple directions. Photos in some posted reports showed Strombolian activity at the active vent.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 15-21 July. The heights and morphologies of the SW and central lava domes were unchanged from the previous week, and seismicity remained at high levels. As many as 22 lava avalanches traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 1.8 km.

Pavlof – Alaska Peninsula, Alaska : AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 19-26 July. Seismic tremor persisted and multiple daily explosions were detected in seismic and infrasound data. Elevated surface temperatures were identified almost daily in satellite images; weather clouds sometimes prevented views. Diffuse ash emissions were visible in webcam images during 19-20 July. A low-level ash cloud that rose to 2.6 km (8,600 ft) a.s.l. was observed by a pilot at around 1150 on 22 July and corresponded to a slightly larger explosion detected in infrasound data. Steam emissions were visible in satellite images during 25-26 July.

Reventador – Ecuador : IG characterized the ongoing eruption at Reventador as moderate during 19-26 July. Gas-and-ash plumes, observed with the webcam or reported by the Washington VAAC, rose as high as 1.4 km above the summit and drifted in multiple directions. An active lava flow descending the NE flanks was visible in thermal webcam images during 21-24 July.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 19-26 July. Daily ash-and-gas plumes were identified in IG webcam images and visible in satellite images according to the Washington VAAC. Plumes rose as high as 2 km above the volcano and drifted WNW, W, and S. Incandescent material was seen descending the SE flank during 21-22 July.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 19-26 July. At 1455 on 24 July an ash plume rose 300 m above the summit and drifted SW.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch was characterized by explosions, hot avalanches, and lava-dome extrusion during 15-21 July. A daily thermal anomaly was identified in satellite images, and ash plumes were visible drifting 125 km E and SE during 16 and 18-19 July.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 18-25 July. There were four explosions, producing eruption plumes that rose as high as 1.2 km above the crater rim and ejecting larger material 300 m from the vent. Crater incandescence was observed nightly, and volcanic tremor was occasionally recorded.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 20 July – 26 July 2022

Aira – Kyushu (Japan) : 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.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 14-21 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose up to 3.5 km (11,500 ft) a.s.l. and drifted E and S. A thermal anomaly over the volcano was identified in satellite images during 17-18 July.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 13 July – 19 July 2022

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 7-14 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose up to 3 km (10,000 ft) a.s.l. and drifted E. A thermal anomaly over the volcano was identified in satellite images during 10-11 July. According to observers, an explosion at 1740 local time on 16 July produced an ash plume that rose to 4.5 km (14,800 ft) a.s.l. and drifted 5 km SE.

Turrialba – Costa Rica : OVSICORI-UNA reported that at 0749 on 17 July a brief ash emission from Turrialba rose 200 m above the crater and drifted SW. Minor amounts of ash fell in Irazú Volcano National Park.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 6 June – 12 July 2022

Bezymianny – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Bezymianny was identified in satellite images during 1-7 July.

Great Sitkin – Andreanof Islands (USA) : AVO reported that the eruption at Great Sitkin continued during 6-12 July. Elevated surface temperatures were occasionally identified in satellite images; weather clouds sometimes obscured satellite and webcam views. Seismicity was low, and occasional local earthquakes were recorded. Sulfur dioxide emissions were possibly detected during 9-10 July.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 30 June and 3 and 7 July.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 6-12 July, entering the lava lake and flowing onto the crater floor. The lake level was variable, and occasional lava breakouts occurred along the margins. Low-level spattering from the W vent was visible on most days, with material ejected no more than 10 m above the vent.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 6-12 July. Daily white-and-gray or white, gray, and black emissions rose as high as 700 m above the summit and drifted in multiple directions. Photos in posted reports showed Strombolian activity from the crater.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 1-7 July. The heights and morphologies of the SW and central lava domes were unchanged from the previous week, and seismicity remained at high levels. As many as 60 lava avalanches traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 2 km.

Nyamulagira – DR Congo : Thermal anomalies from lava effusion on Nyamulagira’s crater floor were identified in satellite images on 6 and 11 July.

Nyiragongo – DR Congo : Thermal anomalies from lava effusion on Nyiragongo’s crater floor were identified in satellite images on 1, 6, and 11 July.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 5-12 July, and seismic tremor persisted. Daily elevated surface temperatures identified in satellite images were consistent with the continuing effusion of short lava flows; the lava flow was 380 m long by 27 June. Three small explosions were detected during 0315-0317 on 7 July in seismic and infrasound data. Multiple small explosions were recorded during 10-12 July.

Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 4-10 July with a daily average of 20 explosions. Gas-and-ash plumes rose as high as 2.2 km above the summit and drifted E, SE, and S. As many as six thermal anomalies originating from the lava dome in the summit crater were identified in satellite data. Minor inflation continued to be detected near Hualca Hualca (4 km N).

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 6-12 July. At 0616 on 10 July an ash plume rose 400 m above the summit and drifted SW.

Semisopochnoi – Aleutian Islands (USA) : AVO reported ongoing low-level seismicity, steam emissions, and sulfur dioxide emissions at Semisopochnoi, though no explosive activity had been detected since 12 June.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 1-7 July and the eruption was characterized by ongoing explosions, hot avalanches, and lava-dome extrusion. At 1130 local time on 12 July video and satellite images showed an ash plume drifting 12 km S at altitudes of 4-4.5 km (13,100-14,800 ft) a.s.l.

Stromboli – Aeolian Islands (Italy) : INGV reported that during 4-10 July activity at Stromboli was characterized by ongoing explosions from four vents in Area N (North Crater area) and two vents in Area C-S (South-Central Crater area). Infrequent explosions from the N1 vent (Area N) ejected mostly ash, with some course material. The N2 vent (Area N) mostly emitted gases along with occasional explosions and sustained jetting. Material ejected from Area N rose no higher than about 60 m above the vents. No explosions occurred at the S1 and C vents in Area C-S; explosions that were medium-to-low intensity and frequency at the two S2 vents ejected material no higher than about 30 m.

Suwanosejima – Ryukyu Islands (Japan) : JMA lowered the Alert Level for Suwanosejima to 2 (on a 5-level scale) on 11 July, reflecting declining activity and a reduced likelihood that tephra would be ejected farther than 1 km. The number and intensity of explosions had been variable since early April but decreased overall, and material had not been ejected beyond a 1-km radius. Eruption plume heights had occasionally exceeded 3 km above the crater rim since July 2021 but none that high had been observed since mid-April. The number of volcanic earthquakes had temporality increased on 17 May but were generally low.

Taal – Luzon (Philippines) : PHIVOLCS lowered the Alert Level for Taal to 1 (on a scale of 0-5) on 11 July, noting that during the previous two months activity was characterized by baseline levels of volcanic earthquakes, weak gas emissions, and minor surface activity. Phreatomagmatic bursts from Main Crater were last observed on 2 and 10 February and 26 March. An average of seven daily volcanic earthquakes were recorded during 1 January-31 May, and none were detected after 13 June. Deformation data since January 2020 showed overall deflation. Sulfur dioxide emissions averaged 1,214 tonnes per day during May-July, though the most recent measurement was 237 tonnes per day. Minor emissions from fumarolic vents in Main Crater continued to produce diffuse steam-rich plumes that rose as high as 2.4 km.

Yakedake – Honshu (Japan) : JMA reported that after an increase in the number of small volcanic earthquakes with epicenters near Yakedake’s summit in late May, seismicity remained elevated for a few weeks. Seismicity decreased in mid-June and returned to baseline levels.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 6 June – 12 July 2022

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing during 1-11 July. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose up to 3.2 km (10,500 ft) a.s.l. and drifted NW, NE, and SE. A thermal anomaly over the volcano was identified in satellite images on 3 July.

Yufu-Tsurumi – Kyushu (Japan) : JMA reported that during 0247-0500 on 8 July the seismic network at Yufu-Tsurumi recorded 57 volcanic earthquakes with hypocenters 1-4 km beneath Garandake, a small lava dome on the N flank of the larger Tsurumidake lava dome at the E end of the complex. A total of 92 volcanic earthquakes were recorded by 1100 on 8 July; no additional events were detected through 11 July.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 29 June – 5 July 2022

Chikurachki – Paramushir Island (Russia) : An explosive phase at Chikurachki began at 1230 on 30 June (local time), prompting KVERT to raise the Aviation Color Code to Orange (the second highest level on a four-color scale). Ash plumes from the explosions rose to 4.5 km (14,800 ft) a.s.l. and drifted 300 km W and 50 km SSE. Activity declined by 1230 on 1 July. Gas-and-steam emissions were visible during 2-5 July.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing. A thermal anomaly over the volcano was identified in satellite images on 23 June. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes that rose up to 3.5 km (11,500 ft) a.s.l. and drifted NW, NE, and SE during 24-25 and 30 June.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 22 June – 28 June 2022

Aira – Kyushu (Japan) : 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.

Bezymianny – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Bezymianny was identified in satellite images during 17-26 June.

Dukono – Halmahera : 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.

Great Sitkin – Andreanof Islands (USA) : 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.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 17 and 19-23 June.

Kilauea – Hawaiian Islands (USA) : 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.

Krakatau – Sunda Strait : 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.

Lewotolok – Lembata Island : 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.

Merapi – Central Java : 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.

Ontakesan – Honshu (Japan) : 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.

Pavlof – Alaska Peninsula, Alaska : 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.

Ruang – Sangihe Islands : 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.

Ruapehu – North Island (New Zealand) : 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.

Semeru – Eastern Java : 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.

Semisopochnoi – Aleutian Islands (USA) : 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.

Sheveluch – Central Kamchatka (Russia) : 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.

Suwanosejima – Ryukyu Islands (Japan) : 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.

Whakaari/White Island – North Island (New Zealand) : 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.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 15 June – 21 June 2022

Bezymianny – Central Kamchatka (Russia) : KVERT reported that eruptive activity at Bezymianny that continued during 10-17 June was characterized by strong fumarolic emissions, lava-dome incandescence, and hot avalanches. A daily thermal anomaly was also identified in satellite images.

Chiles-Cerro Negro – Colombia-Ecuador : Recent increased seismicity began in May. Earthquakes were first felt on 12 June by residents near the border of Colombia and Ecuador, in the indigenous reservations of Chiles, Panán, and Mayasquer (Colombia), and in Tufiño (Ecuador). Seismicity continued, and from 0205 on 12 June to 0832 on 14 June there were 260 events clustered in two zones, in the S part of CCNVC (at depths of less than 6 km below the CCNVC summit) and about 9 km SE beneath Caldera de Potrerillos (at depths of 7-9 km). The earthquake swarm activity was similar to other swarms recorded since 2013. A trend of inflation at a rate of approximately 28 mm/year has been recorded since 2016 (the beginning of deformation monitoring) through the end of 2020, when the deformation stabilized. Neither inflation nor deflation was detected during the beginning of 2020 or in 2021. Inflation was again detected in March and was continuing at a rate of 32 mm/year. Data from hydrothermal sites around CCNVC showed variations from previous measurements in gas data, and conductivity, temperature, pH, and morphology of a few of the hot spring locations, though they were a result of changes to the hydrothermal systems and not increased volcanic activity.

Cleveland – Chuginadak Island (USA) : AVO reported that during 15-21 June elevated surface temperatures over Cleveland were sometimes identified in satellite images, reflecting the continuing emissions of hot gases. Weather clouds sometimes prevented views of the volcano. Crater subsidence in the summit crater was detected during the previous several weeks. Sulfur dioxide emissions were detected on 15 and 21 June.

Dukono – Halmahera : Based on satellite and wind model data, the Darwin VAAC reported that during 16-21 June ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted NW and W.

Etna – Sicily (Italy) : INGV reported that during 13-19 June gas emissions rose from Etna’s Southeast Crater (SEC) and Bocca Nuova Crater (BN); the emissions from BN were dense and voluminous on 13 June and drifted SSW. Lava effusion from the vent located at about 2,700 m elevation, along the fissure that had opened on 29 May, had slowed by 13 June and stopped by that evening. Lava continued to erupt from a vent along the 7 June fissure, located at the base of the N wall of the Valle del Bove, advancing to 1,760 m elevation by 14 June. Effusion ceased overnight during 15-16 June.

Great Sitkin – Andreanof Islands (USA) : AVO reported that the eruption at Great Sitkin continued during 8-14 June. Elevated surface temperatures were identified in satellite data almost daily, consistent with lava effusion; weather clouds sometimes obscured satellite and webcam views. Seismicity was low with several small local earthquakes detected by the seismic network.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 10-11 and 15-17 June.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 14-22 June, entering the lava lake and flowing onto the crater floor. The surface of the lava lake was continuously active all week, and nearly continuous breakouts occurred along the margins. The lake level was variable in response to cycles of inflation and deflation. By 17 June the total volume of erupted lava was an estimated 93 million cubic meters, and the lake which had risen a total of 120 m since 29 September 2021.

Krakatau – Sunda Strait : PVMBG reported that several eruptive events at Anak Krakatau were recorded during 15-17 June. Eruptions at 0636, 1337, and 2119 on 15 June, 1241 on 16 June, and 0042 and 1839 on 17 June produced dense gray-to-black ash plumes that rose 300-600 m above the summit and drifted N, SW, and S. A few of the webcam images posted with the reports showed ejected incandescent material.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 14-22 June. An eruptive event at 1501 on 16 June produced a white-to-gray ash plume that rose about 700 m above the summit and drifted W and NW. Another event at 1127 on 17 June generated a dense gray ash plume that rose about 1 km and drifted W.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 10-16 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 58 lava avalanches traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 1.8 km. Seismicity remained high.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 14-21 June, and seismic tremor persisted. Daily elevated surface temperatures identified in satellite images were consistent with the continuing effusion of short (500 m or less) lava flows.

Reventador – Ecuador : IG reported that a high level of activity continued at Reventador during 14-22 June, though cloudy weather conditions sometimes prevented visual observations. Gas-and-ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 1.7 km above the summit and drifted mainly NW and W. Incandescence from the crater was often visible at night or during the early morning.

Ruapehu – North Island (New Zealand) : On 20 June GeoNet reported continuing unrest at Ruapehu. Tremor levels had been characterized as weak to moderate for the previous three weeks but increased for a brief period. Levels increased sharply during the evening of 17 June, fluctuated between moderate and strong levels on 18 June, and then decreased to weak levels by 19 June. Lake water temperatures continued to decline, reaching 22 degrees Celsius.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 14-22 June. Daily ash-and-gas plumes were identified in webcam images, and seen in satellite images by the Washington VAAC. Plumes rose as high as 2.4 km above the volcano and drifted W and SW; ashfall was reported in Retén Ichubamba (35 km WNW) and Chauzán San Alfonso (40 km W) during 14-16 June. Almost every day multiple thermal anomalies over the volcano were visible in satellite data. Weather clouds sometimes obscured views of the volcano.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 14-21 June. Periods of weak tremor were recorded by the seismic network. Weather clouds often prevented satellite and webcam views; minor steam emissions were visible in one clear webcam image on 17 June.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 10-17 June and explosions, hot avalanches, and lava-dome extrusion continued. A daily thermal anomaly was identified in satellite images. Webcam images recorded explosions on 10 June that sent ash plumes to 6.5 km (21,300 ft) a.s.l. The ash plumes were visible in satellite images drifting 130 km SE. At 0847 on 20 June (local time) explosions were recorded in webcam images. Ash plumes rose to 7 km (23,000 ft) a.s.l. and drifted 10 km E.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 13-20 June. Crater incandescence was visible at night. Emissions rose as high as 1.6 km above the crater rim and material was ejected as far as 300 m from the vent.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 15 June – 21 June 2022

Bulusan – Luzon (Philippines) : PHIVOLCS reported that unrest continued at Bulusan during 15-21 June. Emissions, sometimes voluminous, rose 100-500 m above the summit and drifted NW, WSW, and SW. Daily sulfur dioxide emissions were 660-1,255 tonnes per day. During 0500-2345 on 20 June the seismic network recorded 65 volcanic earthquakes, including one low-frequency volcanic earthquake; most of the events were weak and shallow.

Ebeko – Paramushir Island (Russia) _ KVERT reported that small phreatic bursts were visible at Ebeko during 11-15 June along with periodic, moderate explosions that generated ash up to 2.5 km (8,200 ft) a.s.l.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 8 June – 14 June 2022

Aira – Kyushu (Japan) : 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.

Bezymianny – Central Kamchatka (Russia) : KVERT reported that eruptive activity at Bezymianny was characterized by strong fumarolic emissions, lava-dome incandescence, and hot avalanches continued during 4-9 June. A daily thermal anomaly was identified in satellite images.

Dukono – Halmahera : Based on satellite and wind model data, the Darwin VAAC reported that during 8-14 June ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted NW, W, and SW.

Erta Ale – Ethiopia : On 2, 7, and 12 June infrared satellite data showed two thermal anomalies of variable intensities in Erta Ale’s S pit crater.

Etna – Sicily (Italy) : INGV reported that during 6-12 June explosive activity at Etna’s Southeast Crater (SEC) produced sporadic and minor ash emissions that rapidly dispersed. The fissure located at the upper part of the Valle del Bove, between 2,700 and 2,900 m elevation, continued to produce lava flows at a variable rate. The flows were most active between 2,000 and 2,100 m elevation but overall were visibly cooling during the week. Flows from the fissure that had opened on 7 June at the base of the N wall of the Valle del Bove, at 1,979 m elevation, had traveled 170 m and were also cooling. A new fissure with three active vents opened on 11 June around 1,900 m elevation. Lava effusion was slow, and the flow only traveled a few tens of meters.

Great Sitkin – Andreanof Islands (USA) : AVO reported that the eruption at Great Sitkin continued during 8-14 June. Elevated surface temperatures were identified in satellite data almost daily, consistent with lava effusion. Seismicity was low.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 4-9 June.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 8-14 June, entering the lava lake and flowing onto the crater floor. The surface of the lava lake was continuously active all week, and the lake level was relatively stable. Nearly-continuous breakouts of lava occurred along the margins of the lake. The sulfur dioxide emission rate was approximately 1,900 and 1,350 tonnes per day on 8 and 10 June, respectively.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 8-14 June. Daily white-and-gray emissions rose as high as 1 km above the summit and drifted in multiple directions. The summit crater was often incandescent, and a 200-m-long lava flow was active W of the summit.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 3-9 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 75 lava avalanches, reaching a maximum distance of 2 km, traveled down the Bebeng drainage on the SW flank. Seismicity remained high.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 8-14 June, and seismic tremor persisted. Daily elevated surface temperatures identified in satellite images were consistent with the continuing effusion of short (500 m or less) lava flows. Diffuse, low-level ash emissions were visible in webcam images on 13 June.

Popocatepetl – Mexico: CENAPRED reported that the eruption at Popocatépetl continued during 7-14 June. Each day there were 9-36 steam-and-gas emissions that rose from the crater and drifted in multiple directions.

Ruapehu – North Island (New Zealand) : On 14 June GeoNet reported that unrest at Ruapehu continued to decline. During the previous week volcanic tremor levels were weak, but remained above background levels recorded since 2013. Lake water temperatures had dropped to 23 degrees Celsius, which corresponded to the long-term average heat flow. Relatively high sulfur dioxide and carbon dioxide measurements were recorded in mid-May, but weather conditions prevented gas measurement flights after that time.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 8-14 June. VONAs were issued for a few eruptive events (recorded at 0547 on 10 June, 0546 on 11 June, 0521 on 13 June, and at 0546 on 14 June) that produced ash plumes that rose 200-500 m above the summit and drifted in multiple directions.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 7-14 June. Seismicity remained elevated with intermittent tremor and occasional explosions. Minor ash emissions rising to low altitudes (less than 1.5 km (5,000 ft) a.s.l.) were visible in webcam images on most days; weather clouds sometimes prevented satellite and webcam views.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 4-9 June and explosions, hot avalanches, and lava-dome extrusion continued. A daily thermal anomaly was identified in satellite images.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 6-13 June. Crater incandescence was visible at night. One explosion was recorded during 6-10 June, producing a plume that rose 2 km above the crater rim and ejecting material 300 m away from the vent. During 10-13 June eruption plumes rose as high as 1.5 km above the crater rim and material was ejected as far as 300 m from the vent.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 8 June – 14 June 2022

Bulusan – Luzon (Philippines) : PHIVOLCS reported that increased seismicity at Bulusan began at 0500 on 9 June, characterized by a total of 45 volcanic earthquakes, including two low-frequency events. Most of the events were low magnitude and shallow. A phreatic eruption was detected at 0337 on 12 June. Plumes were not visible in webcam images due to darkness, but residents of Inlagadian (Casiguran municipality) briefly saw incandescence at the base of a plume. In data from seismic and infrasound instruments the event was classified as an explosion-type earthquake which lasted about 18 minutes. An explosion was felt by residents within 5 km, including in the barangays of Añog (Juban) and Inlagadian. Rumbling was heard in Sitio Bagong Barrio, and in barangays of Santa Lourdes (Barcelona), Inlagadian and San Juan (Casiguran), Bentuco (Gubat), and Añog, Calateo, and Puting Sapa (Juban). Sporadic ash emissions began to be observed at 0430. At daybreak emissions were visible rising from six vents: Blackbird Crater (the main crater), three explosion pits in the summit crater, and two vents on the NW and N sides of the summit. Steam, gas, and ash plumes rose 400-750 m above the summit and drifted several kilometers NW. Ash carried by winds fell in areas as far as 50 km NW, in Sorsogon City and Palanas, Pilar, Sorsogon Province, across Sorsogon Bay, and as far as Anislag, Daraga, Albay. Ash on the upper NW flanks was visible, and several barangays in the municipalities of Casiguran, Juban, and Magallanes experienced minor ashfall. Emissions continued throughout the day. According to a news article more than 11,000 people (at least 2,800 families) in Juban evacuated, and flights in and out of the Bicol International Airport were cancelled. After the eruption gas emissions rose from the main crater and, for the first time this year, from the NW summit vent.

Krakatau – Sunda Strait : PVMBG reported that an eruptive event at Anak Krakatau was recorded at 1159 on 8 June, producing a dense white-to-gray ash plume that rose about 500 m above the summit and drifted SW. At 1304 a dense gray ash plume rose around 500 m and drifted S.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week 1 June – 7 June 2022

Bulusan – Luzon (Philippines) : At 1037 on 5 June a phreatic eruption at Bulusan produced a gray steam-rich plume, somewhat visible through weather cloud cover, that rose at least 1 km above the summit and drifted W. The event lasted about 17 minutes and was visible from Juban (Sorsogon Province). Ashfall was reported in Puting Sapa, Añog, Guruyan, Catanusan, Buraburan, Bacolod, and Sangkayon in Juban, and Bolos in Irosin, Sorsogon Province. Residents of Añog, Guruyan, and Catanusan also reported rumbling sounds and a sulfur odor. PHIVOLCS raised the Alert Level to 1 (on a scale of 0-5) and 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. After the eruption gas emissions rose from the main crater and, for the first time this year, from the NW summit vent.

Reykjanes – Reykjanes Peninsula : On 2 June IMO reported that the rate of uplift on the Reykjanes Peninsula had significantly decreased, and seismicity had been declining, with only about 150 earthquakes recorded the previous day. The Aviation Color Code was lowered to Green because the data indicated no magma movement.

Ulawun – New Britain (Papua New Guinea) : RVO reported that at 0820 on 2 June a small eruption at Ulawun produced dense gray ash plumes that rose about 3 km above the summit and drifted NW. The elevated activity lasted 10-15 minutes. Minor ashfall was reported in areas downwind, including in Ulamona Mission and on Lolobau Island. Seismicity increased during the event, then dropped back to lower levels. Diffuse white plumes were visible rising from the summit the next day.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 25 May – 31 May 2022

Aira – Kyushu (Japan) : 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.

Ambae – Vanuatu : On 27 May the Vanuatu Meteorology and Geo-Hazards (VMGD) reported that the cone in Ambae’s Lake Voui continued to produce steam and ash emissions.

Dukono – Halmahera : Based on satellite and wind model data, the Darwin VAAC reported that during 26-28 and 30-31 May ash plumes from Dukono rose to 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted in multiple directions.

Etna – Sicily (Italy) : INGV reported that during 23-29 May activity at Etna’s Southeast Crater (SEC) was characterized by intermittent Strombolian activity and occasional ash emissions. At 0805 on 29 May a fissure opened in the upper part of the Valle del Bove. Two vents along the fissure, located at 2,850 and 2,730 m elevation, produced slow-moving lava flows that had advanced E to 2,090 m elevation by the next day. During an aerial survey conducted on 30 May scientists observed a series of about four arc-shaped fractures on the E flank of SEC, between 3,000 and 3,200 m elevation, and unstable and slumped material which had moved downslope.

Fuego – South-Central Guatemala : INSIVUMEH reported that 2-9 explosions per hour were recorded at Fuego during 24-31 May, generating ash plumes that rose as high as 1.1 km above the crater rim. The ash plumes drifted as far as 30 km in multiple directions, causing ashfall on most days in areas downwind including La Soledad (11 km N), Chimaltenango (21 km NNE), Parramos, Yepocapa (8 km N), Quisaché, Santa Isabel, La Rochela, El Zapote (10 km S), and La Trinidad (S). Ashfall was probable but not reported on three of the days. Daily shock waves rattled structures in communities around the volcano and occasional rumbling was heard. Block avalanches descended the upper flanks in all directions, but most commonly were visible in the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, and Las Lajas (SE) drainages. Explosions ejected incandescent material 100-400 m above the summit on most days. Lahars descended the Ceniza and El Jute (SE) drainages during 27-28 May.

Gaua – Banks Islands (Vanuatu) : On 27 May Vanuatu Meteorology and Geo-Hazards (VMGD) reported that steam emissions continued to be emitted at Gaua based on satellite images and local observers. The steam plumes may have contained volcanic gases.

Great Sitkin – Andreanof Islands (USA) : AVO reported that the eruption at Great Sitkin continued during 24-31 May, though weather clouds sometimes hindered observations. Almost daily elevated surface temperatures were identified in satellite data, consistent with lava effusion, and satellite images during 28-29 May showed that the lava field had expanded. Steam emissions were occasionally visible.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 20 and 23-27 May.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 24-31 May, entering the lava lake and flowing onto the crater floor. The surface of the lava lake was continuously active all week, though the height of the lake was high and relatively stable. Nearly-continuous breakouts of lava occurred along the NW and W margins of the lake.

Kuchinoerabujima – Ryukyu Islands (Japan) : The number of volcanic earthquakes had decreased to low levels. The report noted that sulfur dioxide emissions had continued to remain low, and that no changes in temperature or the extent of the geothermal areas around the crater were observed.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during the month of May. White, gray, and black plumes rose as high as 1.2 km above the summit crater, and white-and-gray plumes rose 100-500 m. Lava flows were active on the crater floor. On 31 May lava flow breached the E crater rim and traveled 500 m E, towards the Jontona Village, located 4 km E of the summit.

Manam – Northeast of New Guinea : The Darwin VAAC reported daily ash plumes at Manam during 25-29 May. At 0720 on 25 May an ash plume rose to 2.4 km (8,000 ft) a.s.l. and drifted W, and dissipated within 30 minutes. Ash plumes rose to 2.1 km (7,000 ft) a.s.l. and drifted NW during 25-26 May. An eruptive event, observed at 0657 on 27 May by RVO and webcam images, produced an ash plume that rose to 2.4 km a.s.l. based on webcam views; weather clouds prevented satellite views of the emissions. On 28 May an ash plume rose to 2.1 km a.s.l. and drifted NE. A thermal anomaly over the volcano was visible following the emission. On 29 May diffuse ash plumes rose to 2.1-2.4 km a.s.l. and drifted in multiple directions.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 20-26 May. 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 144 lava avalanches traveled a maximum of 2 km down the Bebeng drainage on the SW flank. Three pyroclastic flows traveled 2 km down the Bebeng drainage. Seismicity remained high.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 24-31 May, and seismic tremor persisted. Daily elevated surface temperatures were identified in satellite images consistent with the effusion of short lava flows on the upper E flank. An active flow that was 650 m long was visible in satellite images during 28-29 May.

Rincon de la Vieja – Costa Rica : OVSICORI-UNA reported that several small phreatic explosions at Rincón de la Vieja were recorded during 25-28 May. A phreatic explosion at 1730 on 25 May produced minor ashfall on local plants located on the upper flanks. Weather conditions often prevented views of plumes.

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 23-31 May. Incandescence from Caliente crater and the lava flows on the W and SW flanks was visible nightly and during some early mornings. Avalanches of incandescent blocks descended the W, SW, and S flanks of Caliente. The lava flows continued to advance in the San Isidro channel, and produced block avalanches from the ends and sides of the flows that descended the S, SW, and S flanks. Ash from these avalanches fell in areas on and around the volcano. The lava flow was 3.3 km long by 27 May. Cement-like lahars descended the Cabello de Ángel drainage (a tributary of Nimá I on the SE flank) during 27-28 May, carrying tree trunks, branches, and blocks up to 1 m in diameter.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 24-31 May. Several eruptive events (recorded at 0553 and 0627 on 28 May, at 0819 on 29 May, and at 0529 on 30 May) produced ash plumes that rose 300-600 m above the summit and drifted N and SW.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 24-31 May. Seismicity continued to be elevated with intermittent tremor and several daily explosions recorded by infrasound and seismic instruments. Weather clouds often prevented satellite and webcam views; sporadic ash emissions were visible during 27-28 May and likely occurred on other days as well. Sulfur dioxide emissions were detected during 27-29 May, and elevated surface temperatures were identified during 28-29 May.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 20-27 May, and lava-dome extrusion continued.

Stromboli – Aeolian Islands (Italy) : INGV reported that during 23-29 May activity at Stromboli was characterized by ongoing explosions from four vents in Area N (North Crater area) and three vents in Area C-S (South-Central Crater area). During most of the week explosions from Area N vents (N1 and N2) averaged 3-6 events per hour; explosions from the N1 vent ejected lapilli and bombs 80-150 m high, and minor gas emissions and weak spattering was visible at N2 vents. No explosions occurred at the S1 and C vents in Area C-S (except for on 25 May); low- to medium-intensity explosions at the two S2 vents occurred at a rate of 0-4 per hour and ejected coarse material 80-150 m high. At 1611 on 25 May a high-energy explosive event occurred at the N vent in S2, ejecting material beyond the area viewed by the Pizzo webcam, located about 250 m elevation. A second explosion, recorded at 1612 at the C vent, ejected course material 80 m high.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that 33 explosions were recorded at Suwanosejima’s Ontake Crater during 23-30 May. Eruption plumes rose as high as 1.9 km above the crater rim and material was ejected 500 m above the vent. Crater incandescence was visible at night. Ash fell in Toshima village (3.5 km SSW) during 23-27 May. The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater.

Yasur – Vanuatu : On 27 May Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a high level of “major unrest”. Ash-and-gas emissions and loud explosions continued to be recorded, with bombs falling in and around the crater.