Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 13 November – 19 November 2019

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

Asosan | Kyushu (Japan) : JMA reported that the eruption at Asosan that began on 7 October continued through 18 November. The Tokyo VAAC reported that during 13-18 November ash plumes rose to 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted in multiple directions. On 18 November JMA confirmed ashfall in downwind areas.

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 6-12 November ash plumes from Dukono rose to an altitude of 2.1-2.3 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 11-12 and 14 November that sent ash plumes up to 3 km (10,00 ft) a.s.l. Ash plumes drifted E and NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 11-17 November lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.8 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 400 m above the summit. Incandescence from both summit craters was visible at night. The Alert Level remained at 2 (on a scale of 1-4).

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Klyuchevskoy was identified in satellite images during 8 and 10-13 November. Strong crater incandescence was visible at night during 10-11 November. The Aviation colour Code remained at Orange.

Krakatau | Indonesia : PVMBG reported that sometimes during 11-17 November dense white plumes rose as high as 150 m above Anak Krakatau’s active vent. The seismic network detected one eruptive event; dense gray-to-black plumes rose as high as 300 m above the vent. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Merapi | Central Java (Indonesia) : PVMBG reported that after the eruption at Merapi on 9 November seismicity increased and remained elevated. At 1046 on 17 November an eruption was recorded by the seismic network for two minutes and 35 seconds. An ash plume rose around 1 km above the crater rim and a pyroclastic flow traveled less than 1 km SE down the Gendol drainage. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 12-19 November white-to-gray plumes from Nevados de Chillán’s Nicanor Crater rose 450-900 m above the rim and drifted SE and NE. Occasional explosions ejecting incandescent material onto the flank were visible at night. The volcano Alert Level remained at Orange, the second highest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) reported that an average of 50 explosions of low-to-medium intensity per day occurred at Sabancaya during 11-17 November. Gas-and-ash plumes rose as high as 2.5 km above the summit and drifted SE and S. There were seven thermal anomalies identified in satellite data. The Alert Level remained at Orange (the second highest level on a four-colour scale) and the public were warned to stay outside of a 12-km radius.

Sangeang Api | Indonesia : The Darwin VAAC reported that during 14-19 November discrete and short-lived ash emissions from Sangeang Api rose to 2.4 km (8,000 ft) a.s.l. and drifted NW and W. Thermal anomalies were recorded at least during 18-19 November. The Alert Level remained at 2 (on a scale of 1-4).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 8-15 November. An ash plume rose to 9-10 km (29,500-32,800 ft) a.s.l. on 11 November; ash plumes drifted as far as 1,300 km ESE during 11-12 November. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that incandescence at Suwanosejima’s Ontake Crater was visible during 8-15 November. Occasional eruptive events during 13-15 November generated grayish white plumes that rose as high as 1.5 km above the crater rim. Ashfall was reported in Toshima Village (4 km SSW) on 14 November. The Alert Level remained at 2 (on a 5-level scale).

Volcanos

Global Volcanic Activity – New Activity for the week of 13 November – 19 November 2019

Cleveland | Chuginadak Island (USA) : AVO lowered the Volcano Alert Level for Cleveland to Advisory and the Aviation colour Code to Yellow on 15 November, noting that new satellite data and reanalysis of previous data over the past week showed that lava effusion likely had not begun on 8 November. Regional seismic and infrasound data showed no evidence of eruptive activity during 8-19 November; weakly-to-moderately elevated surface temperatures were sometimes identified in satellite images and steam plumes were sometimes visible in webcam images.

Kirishimayama | Kyushu (Japan) : The number of volcanic earthquakes with hypocenters just below Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, increased around 1900 on 17 November and continued to increase through the next day. JMA raised the Alert Level to 2 (on a scale of 1-5) on 18 November. Bad weather conditions prevented visual webcam observations.

Lateiki | Tonga Islands : Satellite images showed that the mid-October eruption at Lateiki (Metis Shoal) had formed a new and larger island, but by 14 November it had eroded to a size similar to the pre-eruptive size.

Shishaldin | Fox Islands (USA) : AVO reported that the eruption at Shishaldin continued at variable levels during 13-19 November. Seismicity increased during 13-14 November, and elevated surface temperatures were visible in satellite and webcam data. Minor ash emissions were visible and likely resulting from spatter cone collapses. Lava and debris flows had not advanced since 8 November; lava flows had traveled as far as 1.2 km and a large branched network of debris flows extended at least 5.5 km NE. Strongly elevated surface temperatures and a steam plume drifting more than 100 km SE were visible on 15 November. An incandescent lava flow on the NE flank was recorded in webcam images. Activity during 17-18 November was characterized by low seismic tremor and weakly-to-moderately elevated surface temperatures, consistent with cooling lava flows. Seismicity and surface temperatures again increased during 18-19 November. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

White Island | North Island (New Zealand) : GeoNet reported that minor increases in sulfur dioxide emission had been detected at White Island over the past several weeks, and the level of volcanic tremor increased from weak to moderate levels during the previous few weeks. The report noted that the changes are not uncommon and could be related to a variety of processes, though the elevated activity was above the expected range for minor volcanic unrest and associated hazards; GeoNet raised the Volcanic Alert Level for White Island to 2 and the Aviation colour Code to Yellow on 15 November.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 6 November – 12 November 2019

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

Asamayama | Honshu (Japan) : On 6 November JMA lowered the Alert Level for Asamayama to 1 (on a scale of 1-5) noting that no eruptions had occurred since 26 August, volcanic tremor had not been recorded since early September, and volcanic gas emissions had been generally low.

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 6-12 November ash plumes from Dukono rose to an altitude of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 2-6 November that sent ash plumes up to 3 km (10,00 ft) a.s.l. Ash plumes drifted N, E, and SE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 4-10 November lava continued to effuse from Karangetang’s Main Crater (S) and travel down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Incandescent blocks from the flows reached a distance of 1.8 km from the crater. Sometimes dense white plumes rose to 250 m above the summit craters. The Alert Level remained at 2 (on a scale of 1-4).

Krakatau | Indonesia : PVMBG reported that during 4-10 November diffuse white plumes rose as high as 200 m above Anak Krakatau’s active vent. The seismic network detected 30 eruptive events; dense gray-to-black plumes rose as high as 300 m above the vent. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Merapi | Central Java (Indonesia) : PVMBG reported that at 0621 on 9 November an eruption was detected by the seismic network at Merapi and lasted two minutes and 40 seconds. A pyroclastic flow traveled 2 km down the Gendol drainage on the SE flank and an ash plume rose around 1.5 km above the summit. Minor ashfall was reported in areas to the W as far as 15 km away, including Wonolelo, Sawangan, Magelang, and Tlogolele. The event did not notably impact the morphology of the lava dome and the drainage. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.

Sangeang Api | Indonesia : The Darwin VAAC reported that during 6-12 November discrete and short-lived ash emissions from Sangeang Api rose to 3 km (10,000 ft) a.s.l. and drifted NW, W, and SW. Thermal anomalies were visible during 6-8 November. The Alert Level remained at 2 (on a scale of 1-4).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 1-8 November. Ash plumes drifted as far as 640 km NW on 3 and 5 November. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that incandescence at Suwanosejima’s Ontake Crater was visible during 1-8 November. Very small eruptive events on 5 and 7 November generated grayish white plumes that rose 900 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Volcanos

Global Volcanic Activity – New Activity for the week of 6 November – 12 November 2019

Cleveland | Chuginadak Island (USA) : Highly elevated surface temperatures identified in satellite data indicated that slow lava effusion in Cleveland’s summit crater may have begun during 7-8 November. AVO raised the Volcano Alert Level to Watch and the Aviation colour Code to Orange. Robust steaming was visible in satellite and webcam images on 7 November.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images on 6 November. The Aviation colour Code remained at Orange.

Manam | Papua New Guinea : RVO reported that at 1330 on 2 November a single large explosion at Manam generated a dense dark ash plume that rose 1 km above the summit and drifted NW. A shock wave was felt at the Bogia Government station (about 40 km SE) about 1 minute later. RSAM values on 6 November fluctuated between 250 and 360 units but began to increase around 1430 and triggered alerts around 1445. Values continued to increase and reached 400-500 units, heralding an eruption which began during 1600-1630. A gray ash plume rose 1 km and drifted NW. Incandescent material ejecting from the vent was visible at the start of the eruption and became more visible as the evening grew darker. The eruption peaked in intensity around 1930, then declined and ceased during 2100-2200.

Popocatepetl | Mexico : During an overflight of Popocatépetl on 5 November CENAPRED scientists, researchers from Instituto de Geofísica de UNAM, and members of the Coordinación Nacional de Protección Civil observed lava dome number 85 in the bottom of the inner summit crater. The dome was 210 m in diameter, 80 m thick, and had an irregular surface. The inner crater remained 350 m in diameter and was 90 m deep. CENAPRED reported that each day during 6-12 November there were 58-148 steam-and-gas emissions, some of which contained ash. Explosions at 0300 and 0501 on 6 November and at 0023 and 0655 on 7 November ejected incandescent tephra onto the upper flanks. Five more explosions were detected on 6 November. Eruptive events at 0858 and 0941 on 9 November generated ash plumes that rose 2 km above the crater rim and drifted NW; between those two ash emissions explosions were recorded at 0923 and 2055. Explosions on 10 November were recorded at 0648 and 1636. An explosion at 2203 on 11 November ejected incandescent tephra as far down the E flank as 1.5 km and generated an ash plume that rose 2 km and drifted NE. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Shishaldin | Fox Islands (USA) : AVO reported that the eruption at Shishaldin continued at variable levels during 5-12 November. Periods of high-amplitude tremor during 5-6 November were likely related to increased lava effusion and fountaining, though weather clouds prevented visual confirmation. Intermittent advancement of active lava flows and lahars on the N flank were confirmed in RADAR data, and by 7 November the lava flow was 1.3 km long and the debris flow runout was 5 km. Seismic tremor was low during 8-9 November suggesting lava effusion was less likely; weather cloud cover continued to obscure views, though elevated surface temperatures were sometimes detected during brief periods of clear weather. Activity significantly increased during 10-11 November with lava fountaining visible in webcam views throughout the evening and night. Strongly elevated surface temperatures at the summit and along the flanks were visible in satellite data. Ash emissions reported by pilots and visible on webcam images rose as high as 3.7 km (12,000 ft) a.s.l. and drifted N. Activity decreased during 11-12 November. Strongly elevated surface temperatures were consistent with cooling lava flows. Seismicity decreased during the evening of 11 November and remained low. Minor steam-and-ash emissions were visible in webcam images. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 30 October – 5 November 2019

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

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 30 October-5 November ash plumes from Dukono rose to an altitude of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NE, E, and SE. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 25-26 and 29-30 October that sent ash plumes up to 2.5 km (8,200 ft) a.s.l. Ash plumes drifted E and NE. A weak thermal anomaly was identified in satellite images on 29 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ibu | Halmahera (Indonesia) : PVMBG reported that during 1-5 November white-and-gray plumes from Ibu rose 200-800 m above the summit and drifted E and N. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 1-5 November lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.5 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 200 m above the summit. The Alert Level remained at 2 (on a scale of 1-4).

Kerinci | Indonesia : PVMBG reported that at 0614 on 30 October a brownish-white ash emission from Kerinci rose around 800 m above the summit and drifted NE, E, and SE. Brownish ash emissions rose 800 m and drifted WSW at 1721 on 30 October and to 500 m and drifted ESE at 0543 on 1 November. An eruptive event at 0553 on 2 November generated a brown ash emission that rose 500 m and drifted ESE. During 3-5 November brown ash plumes rose 100-500 m. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) reported that an average of 28 low-to-medium intensity explosions per day occurred at Sabancaya during 28 October-3 November. Gas-and-ash plumes rose as high as 2 km above the summit and drifted W, SW, and S. There were nine thermal anomalies identified in satellite data. The Alert Level remained at Orange (the second highest level on a four-colour scale) and the public were warned to stay outside of a 12-km radius.

Sangeang Api | Indonesia : The Darwin VAAC reported that during 30-31 October and 3-4 November discrete and short-lived ash emissions from Sangeang Api rose 2.7-3.5 km (9,000-11,000 ft) a.s.l. and drifted NW, W, and SW. Thermal anomalies were visible on 3 and 5 November. The Alert Level remained at 2 (on a scale of 1-4).

Semeru | Eastern Java (Indonesia) : The Darwin VAAC reported that on 30 October an ash plume from Semeru rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted SE and S based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 25 October-1 November. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Stromboli | Aeolian Islands (Italy) : INGV reported that during 30 October-5 November activity at Stromboli was characterized by ongoing Strombolian activity and degassing from multiple vents within the crater terrace. Explosions originated at a rate of 2-13 per hour from vents in Area N (north crater area) and at a rate of 7-16 per hour from vents in Area C-S (south central crater area). Explosions from Area N ejected lapilli and bombs no more than 175 m high, while explosions at Area C-S ejected tephra to heights under 250 m.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that at 1225 on 19 October a very small eruptive event at Suwanosejima’s Ontake Crater generated a gray plume that rose 300 m above the crater rim. A small amount of ash fell in Toshima, 4 km SW. Very small eruptions during 29-30 October generated grayish-white plumes that rose 800 m. Ashfall was reported in Toshima on 29 October. The Alert Level remained at 2 (on a 5-level scale).

Yasur | Vanuatu : On 31 October the Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that recent observations and data from Yasur’s seismic network confirmed ongoing sometimes strong explosions. The Alert Level remained at 2 (on a scale of 0-4). VMGD reminded residents and tourists that hazardous areas were near and around the volcanic crater, within a 395-m-radius permanent exclusion zone, and that volcanic ash and gas could reach areas impacted by trade winds.

Volcanos

Global Volcanic Activity – New Activity for the week of 30 October – 5 November 2019

Kikai | Japan : An eruption at Satsuma Iwo-jima, a subaerial part of Kikai’s NW caldera rim, was detected at 1735 on 2 November, prompting JMA to raise the Alert Level to 2 (on a 5-level scale). A grayish-white plume rose 1 km above the Iodake crater rim. The report noted that the number of volcanic earthquakes has been low, with no variations before or after the event. The next day during an overflight conducted by the Coast Guard and the Japan Meteorological Agency Mobile Survey Team (JMA-MOT) observers noted no changes to the geothermal field and no new deposits from the event the day before. Views of the crater were obscured by white plumes rising 300 m above the crater rim.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that ash plumes and steam-and-gas plumes with some ash drifted 130 km SW on 25 October according to video and satellite data. A weak thermal anomaly was identified in satellite images during 26-27 and 30 October. The Aviation colour Code remained at Orange.

Metis Shoal | Tonga Islands : GeoNet reported that by 1 November the eruption at Metis Shoal (Lateiki) had formed an elongated island, with no visible evidence of the old 1995 dome. According to a news article the new island is about 100 m wide and 400 m long, and had emerged at a location 120 m away from the former island. The article noted that the eruption had ceased.

Shishaldin | Fox Islands (USA) : AVO reported that by 28 October two stalled lava flows extended as far as 1.8 km down Shishaldin’s NW flank, lahars had traveled at least 4 km down the NW flank, and trace ash deposits on the N flank were identified in satellite images. Activity paused during 29-30 October but resumed on 31 October. Numerous small explosions were detected by the local seismic network during 31 October-1 November and incandescence was visible in webcam images. There was no evidence of active lava flows outside of the summit crater. During 1-2 November seismicity remained elevated characterized by periods of high-amplitude tremor. Small explosions were recorded in seismic and infrasound data. Elevated surface temperatures were detected in satellite images and incandescence was observed in webcam images overnight. A pilot observed a lava flow in the morning of 2 November. Sporadic incandescence recorded by the webcam overnight during 2-3 November suggested minor explosive activity and/or lava fountaining. On 3 November lava overflowed the summit crater and traveled at least 400 m down the NW flank and 300 m down the SE flank. By 4 November the flow on the NW flank had branched and lengthened to 1 km. Lahars were as long as 2 km on the N and S flanks. Spatter deposits from explosions or fountaining were visible on the summit cone. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 23 October – 29 October 2019

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

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 23-29 October ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 18, 20-21, and 23 October that sent ash plumes up to 3 km (10,000 ft) a.s.l. Ash plumes drifted N, E, and SE. A weak thermal anomaly was identified in satellite images on 20 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kanlaon | Philippines : On 25 October PHIVOLCS lowered the Alert Level for Kanlaon to 0 (on a scale of 0-5) noting that volcanic activity had declined to baseline levels in June and had continued to be low.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 21-27 October lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.8 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Incandescence from both summit craters was visible at night. Sometimes dense white plumes rose to 500 m above the summit. The Alert Level remained at 2 (on a scale of 1-4).

Krakatau | Indonesia : PVMBG reported that during 21-27 October diffuse white plumes rose as high as 100 m above Anak Krakatau’s active vent. As many as three eruptive events per day during 25-27 October generated ash plumes that rose as high as 200 m above the vent. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 22-24 October white-to-gray plumes from Nevados de Chillán’s Nicanor Crater rose as high as 1.3 km above the rim and drifted SE. Explosions ejecting incandescent material onto the flank were visible at night. A new lava flow from the crater had begun to effuse on 16 October and continued to very slowly advance on the NE flank. Diffuse white plumes rose from the crater on 25 and 29 October; cloudy weather obscured views in between those dates. The volcano Alert Level remained at Orange, the second highest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.

Piton de la Fournaise | Reunion Island (France) : OVPF reported that inflation began to be detected at Piton de la Fournaise on 11 October and a seismic crisis was recorded on 21 October. A second seismic crisis began at 0415 on 25 October accompanied by rapid deformation. Volcanic tremor began at 1440, signaling the arrival of magma to the surface; the eruption area was not visible in webcam views. Field observers first saw two active fissures at the S part of l’Enclos Fouqué at an elevation of 1,400 m. Several lava flows were identified, with the front of the longest flow reaching an area 2 km upstream from National Road RN2 by 1700. Tremor intensity began to decline around three hours after the start of the eruption and continued to decline through the morning of 26 October. That same morning there was one active vent producing 10-20-m-high lava fountains. Downstream of piton Tremblet the flow forked and by 1700 on 26 October the leading toe was about 250 m from RN2. On 27 October tremor intensity fluctuated concurrently with the variable intensity of cone formation. The cone had grown to 10 m high and lava was ejected 20 m above the cone rim. Only one lava flow was active and was 200 m long; the flow near RN2 had not progressed. The eruption ceased at 1630.

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) reported that an average of 48 low-to-medium intensity explosions per day occurred at Sabancaya during 21-27 October. Gas-and-ash plumes rose as high as 2.5 km above the summit and drifted W, SW, and S. There were 15 thermal anomalies identified in satellite data. The report noted that the lava dome in the summit crater had been slowing extruding since February and filling in the N part of the crater, though the rate of the extrusion had increased in recent months. On 26 October Observatorio Vulcanológico del INGEMMET (OVI) conducted a drone overflight and captured video of the lava dome. The estimated volume of the lava dome was 4.6 million cubic meters based on the footage. The Alert Level remained at Orange (the second highest level on a four-colour scale) and the public were warned to stay outside of a 12-km radius.

Sangeang Api | Indonesia : The Darwin VAAC reported that during 26-28 October multiple discrete ash emissions from Sangeang Api rose to 2.1-2.7 km (7,000-9,000 ft) a.s.l. and dissipated rapidly to the NW, WNW, and W. A thermal anomaly was visible in satellite images on 26 October. The Alert Level remained at 2 (on a scale of 1-4).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 18-25 October. Resuspended ash drifted 110 km SE during 19-20 October. Explosions recorded on 21 October generated ash plume that rose to 10-11 km (32,800-36,100 ft) a.s.l. and drifted 1,300 km SE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

White Island | North Island (New Zealand) : GeoNet reported that sulfur dioxide emissions and the level of volcanic tremor both increased at White Island over the past several months, and were at the highest levels since 2016. The report noted that the changes could be related to a variety of processes, including an increased level of unrest, though the level of hazards on the island remained unchanged; the Volcanic Alert Level remained at 1 (the second lowest level on a 0-5 scale) and the Aviation colour Code remained at Green. The crater lake level continued to rise and impact surface activity around vents, creating small-scale geysering, on the W side of the crater floor.

Volcanos

Global Volcanic Activity – New Activity for the week of 23 October – 29 October 2019

Klyuchevskoy | Central Kamchatka (Russia) : A small amount of ash began to be visible in gas-and-steam emissions at Klyuchevskoy beginning at 1020 on 24 October, prompting KVERT to raise the Aviation colour Code to Yellow (the second lowest level on a four-colour scale). Later that day video images showed an ash plume rising as high as 6 km (19,700 ft) a.s.l. and drifting 40 km NE. The Aviation colour Code was raised to Orange. KVERT and the Tokyo VAAC noted that during 25-28 October ash plumes rose to 5.5 km (18,000 ft) a.sl. and drifted 15-20 km SE, E, and NW. A weak thermal anomaly over the volcano was identified on 18 and 24 October.

Kuchinoerabujima | Ryukyu Islands (Japan) : A large shallow earthquake at Kuchinoerabujima was recorded at 2133 on 27 October, prompting JMA to raise the Alert Level to 3 (the middle level on a scale of 1-5) within a few hours. The report also stated that the number of volcanic earthquakes had increased on 18 October. A large earthquake was also detected on 18 October but had occurred at a slightly deeper location (below the W part of Shindake Crater) than the 27 October event.

Pavlof | United States : AVO reported that after a small explosion at Pavlof was recorded on 19 October and before 25 October clear satellite and webcam views did not show any deposits associated with the event. Weakly elevated surface temperatures and a small steam plume were occasionally visible. No other activity was detected during 26-29 October. The Aviation colour Code remained at Yellow and the Volcano Alert Level remained at Advisory.

Shishaldin | Fox Islands (USA) : Pilot and local observations as well as webcam views all indicated that the incandescence at Shishaldin’s summit crater was from low-level Strombolian activity during 21-22 October. Seismicity and infrasound signals were consistent with low-level eruptive activity, and a steam plume was persistent. By 23 October lava had filled the crater and during 23-24 October overflowed the N crater rim. A 200-m-long lava flow on the N flank melted snow and caused a lahar which traveled 2.9 km and stopped at about 1,230 m elevation. A smaller lava flows caused a 1-km-long lahar to descend the NE flank. Spatter accumulated around the crater rim and melted snow. On 25 October AVO noted that trace ash deposits had extended at least 8.5 km SE. Low-level eruptive activity continued during 26-29 October. Seismicity remained elevated, with periods of high-amplitude tremor. Small explosions were recorded during 27-28 October. A satellite image from 28 October showed a 850-m-long SWIR anomaly on the NW flank from a lava flow. A central spatter cone was visible. Spatter deposits on the snow at the upper flanks was evident, and tephra deposits extended about 2.5 km N. The lahar on the NW flank branched extensively at lower elevations and was at least 5 km long. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Volcanos

Global Volcanic Activity – New Activity for the week of 16 October – 22 October 2019

Masaya | Nicaragua : According to news reports, ash was emitted from Masaya on 15 October, causing very minor ashfall in Colonia 4 de Mayo, 6 km NW.

Metis Shoal | Tonga Islands : The Wellington VAAC reported that on 22 October pilots observed intermittent white plumes rising from Metis Shoal (Lateiki) to 3.7 km (12,000 ft) a.s.l. There was no ash signature in the plumes.

Pavlof | United States : On 19 October small explosion signals at Pavlof were detected by the infrasound network located at Sand Point and on the local seismic network, prompting AVO to raise the Aviation Colour Code to Yellow and the Volcano Alert Level to Advisory. Clouds obscured satellite views of the volcano around the time of the event; slightly elevated surface temperatures were detected in satellite images during 19-20 October.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 9 October – 15 October 2019

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

Ambrym | Vanuatu : Vanuatu Meteorology and Geo-Hazards Department (VMGD) reported that data and observations during February-October indicated that conditions at Ambrym had become stable after the eruption in December 2018 that focused on the summit caldera and East Rift Zone. On 10 October the Alert Level was lowered to 1 (on a scale of 0-5) indicating minor unrest. VMGD warned the public to stay outside of the Permanent Danger Zone defined as a 1-km radius from Benbow Crater and a 2-km radius from Marum Crater, and additionally to stay away from the ground cracks resulting from the December 2019 eruption (a 500-m-radius around the major cracks at Paamal village).

Asosan | Kyushu (Japan) : JMA reported that during 7-15 October ash plumes rose as high as 1.3 km above Asosan’s summit crater rim, causing ashfall in areas downwind including periodically at the Kumamoto Regional Meteorological Observatory. Crater incandescence was occasionally visible at night. The sulfur dioxide emission rate was very high at 4,000 tons per day on 11 October. The Alert Level remained at 2 (on a scale of 1-5).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 9-15 October ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : KVERT reported that ash from Ebeko was reported in Severo-Kurilsk (Paramushir Island), about 7 km E, during 4-5 October. Volcanologists in Severo-Kurilsk observed explosions during 7-8 and 10 October that sent ash plumes up to 2.5 km (8,200 ft) a.s.l. and drifted E and NE. A weak thermal anomaly was identified in satellite images on 8 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ibu | Halmahera (Indonesia) : PVMBG reported that at 0707 on 15 October an ash plume from Ibu rose at least 400 m above the summit and drifted S. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 7-15 October lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.5 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 400 m above the summit. The Alert Level remained at 2 (on a scale of 1-4).

Krakatau | Indonesia : PVMBG reported that at 1010 and 1226 on 12 October, 1026 on 13 October, and 1228 on 14 October the webcam at Anak Krakatau recorded dense gray-black ash plumes rising about 200 m above the bottom of the crater and drifting N. The 14 October event was recorded by the seismic network for three minutes. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Reventador | Ecuador : IG reported that during 8-15 October seismic data from Reventador’s network indicated a high level of seismic activity, including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions. Weather often prevented views of the summit area, although during clear conditions ash-and-steam plumes were visible rising sometimes higher than 1 km above the crater rim and drifting NW, W, and SW. Crater incandescence was periodically observed at night. Blocks were observed rolling down the flanks on 10 and 14 October.

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) reported that an average of 36 low-to-medium intensity explosions per day occurred at Sabancaya during 7-13 October. Gas-and-ash plumes rose as high as 3.5 km above the summit and drifted SE and SW. There were 15 thermal anomalies identified in satellite data. The Alert Level remained at Orange (the second highest level on a four-colour scale) and the public were warned to stay outside of a 12-km radius.

Semeru | Eastern Java (Indonesia) : The Darwin VAAC reported that during 13-14 September ash plumes from Semeru rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted SW based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 4-11 October. Explosions seen in video and satellite images on 6 and 9 October produced ash plumes that rose 6.5-11 km (21,300-36,100 ft) a.s.l. and drifted 1,100 km E. Resuspended ash drifted 170 km E on 4 and 8 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Volcanos

Global Volcanic Activity – New Activity for the week of 9 October – 15 October 2019

Metis Shoal | Tonga Islands : According to news articles the Tonga Geological Services Office of the Ministry of Lands and Natural Resources stated that several observations indicating a possible eruption at Metis Shoal, also known as Lateiki, were reported during 13-15 October. Real Tonga pilots flying between Tongatapu and Vava’u observed the intermittent plumes rising to 4.6-5.2 km (15,000-17,000 ft) a.s.l. and drifting N on 15 October. Ash in the plumes was not identifiable according to the Wellington VAAC.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 2 October – 8 October 2019

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

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 2-8 October ash plumes from Dukono rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 27 September-4 October that sent ash plumes up to 4 km (13,100 ft) a.s.l. Ash plumes drifted SE, E, and NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that there were 10-18 explosions per hour recorded at Fuego during 2-8 October, generating ash plumes that rose as high as 1.1 km above the crater rim and drifted 10-25 km S, SW, W, and NW. Ashfall was reported in several areas downwind including Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I and II (8 km SW), Finca Palo Verde, San Pedro Yepocapa (8 km NW), and El Porvenir (8 km ENE). Explosions sometimes produced shock waves that rattled houses in nearby communities. Incandescent material was ejected 200-400 m high and caused avalanches of material that occasionally traveled long distances (reaching vegetated areas) down the Seca (W), Taniluyá (SW), Ceniza (SSW), Trinidad (S), El Jute (SE), Las Lajas (SE), and Honda ravines. Lava flows traveled 200 m down the Seca drainage on 6 October and were active in the Santa Teresa (W) drainage on 8 October. Lahars descended the Ceniza, El Mineral, and Seca drainages during 3-7 October, carrying tree branches, trunks, and blocks 1-3 m in diameter.

Hakoneyama | Honshu (Japan) : On 7 October JMA lowered the Alert Level for Hakoneyama to 1 (the lowest level on a 5-level scale), noting that the number of volcanic earthquakes had decreased to background levels after a spike in seismicity was recorded in May. Inflation had been detected but had become almost stagnant after late August. Fumaroles in the Owakudani hot springs area continued to be active, with gas-and-steam plumes rising 100-400 m above their vents.

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that during 6-7 October ash plumes from Ibu rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted S and N based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 30 September-6 October lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.8 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 300 m above the summit. The Alert Level remained at 2 (on a scale of 1-4).

Karymsky | Eastern Kamchatka (Russia) : On 3 October KVERT reported that a weak thermal anomaly over Karymsky continued to be periodically visible in satellite images. Ash explosions were last recorded on 24 September. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Kerinci | Indonesia : PVMBG reported that at 1253 on 6 October a brown ash emission from Kerinci rose around 600 m above the summit and drifted WSW according to a ground observer. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Krakatau | Indonesia : PVMBG reported that Anak Krakatau’s seismic network recorded one eruptive event during 30 September-6 October. A webcam at the summit recorded diffuse white plumes rising as high as 50 m above the crater rim. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Manam | Papua New Guinea : RVO reported that white emissions rose from Manam during 1-7 October and variable crater incandescence from Main Crater was visible at night. Seismicity was at low to moderate levels with RSAM values fluctuating around 300 units. The Darwin VAAC reported that during 3-4 October diffuse ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted N and NW, based on satellite data and weather models. A thermal anomaly was also visible.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 24 September-1 October seismicity at Nevado del Ruiz increased in both frequency and magnitude compared to the previous week. Steam-and-gas plumes rose as high as 1.4 km above the summit and drifted mainly NW. A tremor pulse recorded at 2353 on 29 September was associated with an ash plume that drifted NW and was observed by Parque Nacional Natural los Nevados (PNNN) officials, SGC staff in the field, and residents of Manizales (25 km NW). Seismicity continued to indicate gas-and-ash emissions during 1-4 October. Beginning at 0138 on 4 October seismicity increased; several ash emissions were visible during the morning in webcam images and by SGC staff in the field. The emissions rose as high has 800 m and drifted mainly NW, causing ashfall locally and in Manizales. The Alert Level remained at 3 (Yellow; the second lowest level on a four-colour scale).

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 2-8 October white-to-gray gas plumes from Nevados de Chillán’s Nicanor Crater rose as high as 1 km above the rim and drifted ESE, S, and SE. Explosions on 2 and 6 October ejected incandescent material onto the flank. The lava flow on the NNE flank ceased advancing around 6 October, and small pyroclastic flows were recorded during 6-8 October. The volcano Alert Level remained at Orange, the second highest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.

Santa Maria | Guatemala : INSIVUMEH reported that each day during 2-8 October there were as many as five explosions per hour detected at Santa María’s Santiaguito lava-dome complex. Ash plumes rose 700-900 m above the complex and drifted SW. Avalanches of material descended the SE and S flanks. Ash fell in Monte Claro (S) on 2 October.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 29 September and 1-2 October video and satellite images recorded ash plumes from explosions at Sheveluch rising as high as 9 km (29,500 ft) a.s.l., and a notable pyroclastic flow traveled SE on 1 October. Ash plumes from the events drifted 1,400 km SE and E. On 6 October satellite images showed ash plumes rising to 10 km (32,800 ft) a.s.l. and drifting 430 km NE. The Aviation colour Code was raised to Red (the highest level on a four-colour scale). Later that day the ash plumes were visible in satellite images drifting 1,080 km ENE. The Alert Level was lowered back to Orange.

Tangkubanparahu | Western Java (Indonesia) : PVMBG reported that during 30 September-6 October diffuse white water vapor plumes rose 150 m above the vent on Tangkubanparahu’s Ratu Crater floor. The seismic network recorded continuous tremor. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 1.5 km away from the active crater.

Volcanos

Global Volcanic Activity – New Activity for the week of 2 October – 8 October 2019

Copahue | Central Chile-Argentina border : OVDAS-SERNAGEOMIN and ONEMI reported that during 2-7 October a webcam at Copahue recorded white and gray emissions rising as high as 300 m above the El Agrio Crater rim and drifting ENE, SE, and SSE. By 7 October the number and intensity of seismic events detected at Copahue had decreased to low levels. The volcano Alert Level was lowered to Yellow (second lowest level on a four-colour scale). ONEMI maintained the Yellow Alert (the middle level on a three-colour scale) for residents, and stated that the public should stay at least 1 km away from El Agrio Crater.

Ulawun | New Britain (Papua New Guinea) : RVO reported that the fissure eruption on Ulawun’s WSW flank had ceased by 4 October, producing only diffuse white-to-gray steam plumes with a blueish tinge from the main coalesced vent. Weak incandescence from the vent was visible at night on 5 October. The lava-flow rate slowed to 3-5 m a day, likely because it was no longer being fed. RSAM decreased to 1,000 units; regular small high-frequency events were recorded during 4-7 October. RVO recommended that the Alert Level be reduced to Stage 2.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 25 September – 1 October 2019

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

Asosan | Kyushu (Japan) : JMA reported that during 25-30 September ash plumes rose as high as 1.6 km above Asosan’s summit crater rim and drifted NE and NW, causing ashfall in areas downwind. The sulfur dioxide emission rate was 2,600 tons per day on 26 September. The Alert Level remained at 2 (on a scale of 1-5).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 25 September-1 October ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions. 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.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 22-23 September that sent ash plumes up to 3 km (10,000 ft) a.s.l. Ash plumes drifted E and NE, causing ashfall in Severo-Kurilsk. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Etna | Sicily (Italy) : INGV reported that intense Strombolian activity from vents at the bottom of Etna’s Voragine Crater (VOR) continued during 23-29 September. Gas emissions from Northeast Crater (NEC) were intense and continuous, and ash plumes were occasionally visible and sometimes accompanied by incandescent flashes. A large ash emission rose from the crater on 27 September and drifted S.

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that on 28 September ash plumes from Ibu rose to altitudes of 1.8-2.1 km (6,00-7,000 ft) a.s.l. and drifted WNW based on satellite images and weather models. PVMBG reported that at 1806 on 30 September an ash plume rose about 800 m above the crater rim and drifted N. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 25 September-1 October lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.5 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 300 m above the summit. On 27 and 29 September the Darwin VAAC noted that ash plumes rose to 2.1-2.4 km (7,000-8,000 ft) a.s.l. (about 330-640 m above the crater rim) and drifted SW and W. The Alert Level remained at 2 (on a scale of 1-4).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible in satellite images on 19 September. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Krakatau | Indonesia : PVMBG reported that Anak Krakatau’s seismic network recorded 10 eruptive events during 23-29 September. A webcam at the summit recorded diffuse white plumes rising as high as 150 m from the vent at the bottom of the crater. Eruptive events recorded by the webcam at 0813 on 25 September, 0555 and 0835 on 26 September, and 1520 on 27 September generated dense gray-and-white ash plumes that rose 150-200 m from the vent and generally drifted N. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Manam | Papua New Guinea : The Darwin VAAC reported that on 29 September diffuse ash plumes from Manam rose to altitudes of 2.4-2.7 km (8,000-9,000 ft) a.s.l. and drifted W, based on satellite data and weather models. A sulfur dioxide signature in the plume was also detected. On 30 September RVO reported increased seismicity; the VAAC noted ongoing emissions and a persistent thermal anomaly.

Merapi | Central Java (Indonesia) : PVMBG reported that the lava dome at Merapi slowly grew during 20-26 September and was an estimated 468,000 cubic meters, based on 19 September measurements based on drone photos. Extruded lava fell into the upper parts of the SE flank, generating three block-and-ash flows that traveled as far as 1.5 km down the Gendol drainage. Diffuse white plumes rose as high as 75 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 24 September-1 October white-to-gray gas plumes from Nevados de Chillán’s Nicanor Crater rose as high as 1.3 km above the rim and drifted NE, E, and SE. Explosions sometimes ejected incandescent material onto the flanks. A lava flow on the NNE flank continued to advance at a low rate. Ashfall was reported 15 km WNW in Las Trancas on 24 September. The Alert Level remained at Orange, the second highest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.

Popocatepetl | Mexico : CENAPRED reported that each day during 25 September-1 October there were 123-224 steam-and-gas emissions from Popocatépetl, some of which contained ash. As many as 10 explosions were recorded each day and crater incandescence was sometimes visible at night. During an overflight on 27 September observatory staff, scientists, and civil protection staff observed a lava dome, 30 m in diameter, at the bottom of the inner crater. The inner crater was 350 m in diameter and 150 m deep based on thermal images and photographs. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) reported that an average of 15 low-to-medium intensity explosions per day occurred at Sabancaya during 23-29 September. Gas-and-ash plumes rose as high as 1.7 km above the summit and drifted NW, W, and SW. There were 11 thermal anomalies identified in satellite data. The Alert Level remained at Orange (the second highest level on a four-colour scale) and the public were warned to stay outside of a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch’s lava dome was identified daily in satellite images during 20-27 September. Explosions recorded during 20-21, 23, and 26 September produced ash plumes that rose to 7 km (23,000 ft) a.s.l. and drifted 580 km ESE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Shishaldin | Fox Islands (USA) : On 26 September AVO reported that seismicity at Shishaldin had decreased during the previous few weeks to levels slightly above background. Satellite images indicated decreased surface temperatures at the summit over the same period and showed collapse and slumping of the floor of the summit crater, suggesting a withdrawal of magma. Tiltmeter data suggested that the collapse may have occurred on 19 September. The Aviation colour Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that during 20-27 September white plumes rose 800 m above the rim of Suwanosejima’s Ontake Crater and crater incandescence was visible at night. The Alert Level remained at 2 (on a 5-level scale).

Tangkubanparahu | Western Java (Indonesia) : PVMBG reported that during 23-29 September diffuse white water vapor plumes rose 200 m above the vent on Tangkubanparahu’s Ratu Crater floor. The seismic network recorded continuous tremor. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 1.5 km away from the active crater.

White Island | North Island (New Zealand) : GeoNet reported observing small-scale geyser-like explosions of mud and steam at White Island’s active vent area during the previous three weeks. The ejecta rose as high as 10 m above the active vents on the W part of the crater floor. An increase in frequency of these events was caused by crater lake water that has been rising since early August, covering the active vents. The geysering does not represent increased volcanic activity; the Volcanic Alert Level remained at 1 (the second lowest level on a 0-5 scale) and the Aviation colour Code remained at Green.

Volcanos

Global Volcanic Activity – New Activity for the week of 25 September – 1 October 2019

Copahue | Central Chile-Argentina border : On 30 September OVDAS-SERNAGEOMIN, ONEMI, and SEGEMAR reported that three long-period (LP) earthquakes with notable magnitudes were located about 5.8 km NE of Copahue’s El Agrio Crater. In addition, abundant LP and volcano-tectonic (VT) signals with relatively lower magnitudes were also located in the same area. Some of the events were felt by residents of Caviahue (10 km E) and Copahue 7 km NE) in Argentina. SERNAGEOMIN raised the Alert Level to Orange (second highest level on a four-colour scale) and ONEMI updated the Yellow Alert (the middle level on a three-colour scale) for residents, noting a restriction for entering a 5-km radius from El Agrio Crater. The seismic network recorded a local M 3.1 VT earthquake at 2340 on 30 September, and a local M 3.7 VT event at 0628 on 1 October. The report also noted that 14 lower-energy events (largest was M 2.4) were recorded.

Poas | Costa Rica : OVSICORI-UNA reported that during 16-26 September sulfur dioxide emissions from Poás drifted W and NE, causing a sulfur odor in Alajuela, Heredia, San José, and Cartago. Acidic rain was recorded at the official’s house in the Poás Volcano National Park (PNVP) on 23 September and at Universidad Nacional Costa Rica (UNA) in Heredia on 26 September. At 0540 on 30 September a five-minute-long phreatic eruption ejected sediment, and produced a plume that rose 2 km above the crater rim and drifted SW. Ashfall and a sulfur odor was reported in Trojas de Sarchi and Grecia. Officials closed the PNVP because of the eruption and ongoing elevated seismicity; the park remained closed the next day.

Ulawun | New Britain (Papua New Guinea) : RVO reported that small, discrete, volcano-tectonic earthquakes at Ulawun began occurring more regularly around 1000 on 30 September; by 1130 they were frequent and by 1220 they were characterized as a swarm. The magnitude of the events overall increased with time and some were felt by residents and accompanied by booming sounds. Events were less frequent and intense during 1730-1930. Sometime afterwards RSAM values erratically increased, reaching a high of 10,000 units between 0130 and 0200 on 1 October. The Alert Level was raised to Stage 2 (the second lowest level on a four-stage scale). Periods of volcano-tectonic earthquakes slowly transformed into continuous tremor with distinct bursts of high-frequency signals marking discrete volcano-tectonic events during 0430-0500 on 1 October. During this time a new vent opened in a deep valley on the SSW flank at 700 m elevation. The eruption was described as a distinct incandescent glow formed from ejecting material rising less than 100 m above the vent. By dawn light-gray ash plumes were visible rising several hundred meters and drifting NW. Lava fountaining continued throughout the day, and gray ash plumes rose several kilometers above the vent and drifted W. RVO recommended that the Alert Level be raised to Stage 3. On 2 October lava fountains rose several hundred meters and ash-and-steam plumes rose to variable heights between 2 and 5 km, causing ashfall in Navo (W). A lava flow which emerged during the night traveled 1-2 km NW, though visibility was hindered due to weather conditions. Loud rumbling and roaring was noted. Seismicity remained high with RSAM values passing 12,000 units.