Volcano World

The Darwin VAAC reported that continuous ash plumes from Bagana were identified in satellite images rising to 3.7 km (12,000 ft) a.s.l. and drifting W and SW during 17-20 September. Weather clouds sometimes obscured views.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)

Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported continuing unrest at Kanlaon during 17-24 September, characterized by increased seismicity and sulfur dioxide emissions. The seismic network recorded five volcanic earthquakes during 17-18 September and 15-55 daily volcanic earthquakes during the rest of the week. Weather clouds obscured views of the summit during 17-19 September. Voluminous gas-and-steam emissions rose 300-800 m above the summit and drifted in multiple directions during 20-23 September. Sulfur dioxide emissions were recorded daily and continued to be high, averaging 5,362-10,449 tonnes/day. According to a Disaster Response Operations Monitoring and Information Center (DROMIC) report there were a total of 3,905 people in evacuation centers as of 22 September. The Alert Level remained at 2 (on a scale of 0-5) and PHIVOLCS reminded the public to remain outside of the 4-km-radius Permanent Danger Zone and warned pilots not to fly close to the volcano.

Sources: Disaster Response Operations Monitoring and Information Center (DROMIC),Philippine Institute of Volcanology and Seismology (PHIVOLCS)

Hawaiian Volcano Observatory (HVO) reported that the eruption at Kilauea which began on 15 September from fissures to the W of Napau Crater and on the crater floor continued during 17-19 September, and then paused on 20 September. The eruption area is located in a remote section of the middle East Rift Zone. The opening of new fissures on the Napau Crater floor during 0400-0500 on 17 September was detected using infrasound signals, a thermal anomaly identified in a GOES satellite image, and webcam views. During an overflight later that morning, scientists observed lava fountaining 10 m high along the fissures and lava flows advancing on the crater floor. The activity was vigorous but had started to wane by the afternoon. During an overflight on the morning of 18 September, volcanologists observed only minor activity on the crater floor. Only one vent was active and produced low lava fountains in a tiny pond, and there was some residual movement of lava along a margin of the flow field. A small new flow at the W end of the fissure system was inactive. Steam-and-gas continued to be emitted from the fissures to the W of the crater that had opened on 15 September. New fissures opened W of the crater at around 1515 on 18 September. Flows from lava fountains along the fissure rapidly advanced E and cascaded down the NW wall of Napau Crater onto the crater floor. Sulfur dioxide emissions averaged 10,000 tonnes per day, associated with the opening of the new vents. The lava falls continued overnight during 18-19 September and by around 1000 on 19 September about one-third of the crater floor, or approximately 250,000 square meters, was covered by lava. The amount of coverage suggested that the lava effusion rate was 5-15 cubic meters per second during the most active phase. Activity greatly diminished overnight; the lava channels and falls began to crust over by 2000 and during 2100-2200 they had completely crusted over. Strong incandescence from the vent began to decrease around 0230 on 20 September. Field crews observed minor spattering and small fountains at one end of the vent at around 0830, but by 1000 no activity was seen, and the eruption had paused. In total lava flows covered about 63 hectares (630,000 square meters) of Napau Crater and areas to the W. At 0812 on 23 September the Volcano Alert Level was lowered to Advisory (the second level on a four-level scale) and the Aviation Color Code was lowered to Yellow (the second color on a four-color scale). HVO noted that observations and instrumental data since the pause in the eruption indicated that the potential for renewed eruptive activity had declined. Seismicity in the area was extremely low and no tremor was being recorded. Deformation data showed that magma movement to the middle East Rift Zone has slowed dramatically or stopped altogether. Volcanic gas emissions decreased to near background levels.

Source: US Geological Survey Hawaiian Volcano Observatory (HVO)

According to the Japan Meteorological Agency (JMA) discolored water around Sumisujima was observed on 18 September during an overflight conducted by the Japan Coast Guard. An area of pale-blue to white discolored water extended about 1.8 km NW of the N coast of the island. A very small amount of grayish-white material was floating in the same area as the discolored water and along the W coast. At 1100 on 19 September JMA issued an ?eruption warning? noting that an eruption could affect the surround waters of the island.

Source: Japan Meteorological Agency (JMA)

The Wellington VAAC reported that low-level steam-and-gas emissions from Whakaari/White Island were visible in webcam and satellite images during 18-19 September. The plumes rose 900 m (3,000 ft) a.s.l. and drifted NE; there was no evidence that the plumes contained ash. Views were sometimes obscured by weather clouds.

Source: Wellington Volcanic Ash Advisory Center (VAAC)

Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera?s Sakurajima volcano) during 16-23 September. Crater incandescence was visible in webcam images during dark hours, and there were occasional very small eruptive events. An explosion at 1332 on 16 September generated an ash plume that rose 1.5 km above the crater rim and drifted NW. During a field visit on 18 September sulfur dioxide emissions were high, averaging 2,200 tons per day. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters.

Source: Japan Meteorological Agency (JMA)

Kamchatkan Volcanic Eruption Response Team (KVERT) reported that moderate explosive activity was ongoing at Ebeko during 12-19 September. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E), explosions during 12, 14-17, and 19 September generated ash plumes that rose as high as 2.5 km (8,200 ft) a.s.l. and drifted SW, N, and NE. Satellite data indicated that either no activity was observed, or weather conditions prevented views. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

A 14 September satellite image of Erta Ale showed an oval-shaped thermal anomaly just N of the N pit crater, possibly indicative of an active lava flow. The anomaly was absent in a 19 September image. Small thermal anomalies were visible over both the N and S pit craters in 14, 19, and 24 September images.

Source: Copernicus

Sezione di Catania - Osservatorio Etneo (INGV) reported that mainly gas emissions rose from Etna?s summit craters during 16-23 September. The activity was strongest at Bocca Nuova Crater where the gas emissions were dense and continuous, and occasionally contained ash. A series of explosions at NE Crater began at 2310 on 23 September and were visible in webcam images.

Source: Sezione di Catania - Osservatorio Etneo (INGV)

Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) reported that eruptive activity continued at Fuego during 17-24 September. Daily explosions were recorded by the seismic network, averaging 3-11 per hour when reported. The explosions generated gas-and-ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 30 km in multiple directions. Weak rumbling sounds were reported on most days and shock waves were sometimes detected in local areas. The explosions ejected incandescent material generally up to 200 m above the summit on most days though material was ejected 300-400 m above the summit during 21-22 September. The explosions often produced avalanches of material that descended the flanks, sometimes reaching vegetated areas. Ashfall was reported in areas downwind including Panimach I and II (8 km SW), El Porvenir (10 km S), Santa Sofia (12 km SW), Morelia (10 km SW), Los Yucales (12 km SW), and Yepocpa (8 km NW) during 17-18 September and in La Rochela (8 km SSW), Finca Ceiln (9 km S), El Zapote (10 km SSE), and El Rodeo during 21-22 September. Ashfall was forecast for areas downwind on the other days.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)