Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 15 January 2020 – 21 January 2020

Aira | Kyushu (Japan) : JMA reported nighttime crater incandescence at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-20 January. Small eruptive events were occasionally recorded by the seismic network. A total of 21 explosions were detected, with ash plumes rising as high as 2 km above the crater rim and large blocks ejected as far as 1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Asosan | Kyushu (Japan) : JMA reported that eruptive activity at Asosan was recorded during 7-20 January. Plumes rose 0.9-1 km above the crater rim during 15-20 January and caused ashfall in areas downwind; the Tokyo VAAC reported that ash plumes mainly drifted S, SE, E, and NE. 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 15-21 January ash plumes from Dukono rose 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E, SE, S, and SW. 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 and 13-14 January that sent ash plumes up to 3 km (10,000 ft) a.s.l.; ash plumes drifted E and caused ashfall in Severo-Kurilsk. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that there were 8-17 explosions per hour recorded at Fuego during 14-21 January, generating ash plumes that rose as high as 1.1 km above the crater rim and generally drifted 10-22 km SW and W. 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), Sangre de Cristo (8 km WSW), and El Porvenir (8 km ENE). Explosions sometimes produced shock waves that rattled houses in communities within a 7 km radius, though they were felt up to 25 km away during 19-20 January. Incandescent material was ejected 100-500 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), Honda, and Las Lajas (SE) ravines. Ash plumes drifted 18 km E during 20-21 January.

Ijen | Eastern Java (Indonesia) : PVMBG reported that during 1-18 January white plumes rose 250-400 m above Ijen’s water lake surface and no change in the colour of the water was noted. An increase in the number of shallow volcanic earthquakes was detected; continuous tremor emerged on 11 January, peaked on 15 January, and then decreased during 17-18 January. The temperature of the lake water fluctuated, though overall it decreased from 38 degrees Celsius in June 2019 to 20 degrees Celsius on 14 January; the lake water was 46 degrees Celsius during a period of increased activity from February to March 2018. The Alert Level remained at 1 (on a scale of 1-4), and residents and visitors were advised to not approach the crater rim or descend to the crater floor.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 13-19 January 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 50-300 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 10-12 and 15-16 January. The Aviation colour Code remained at Orange.

Nishinoshima | Japan : The Japan Coast Guard (JCG) reported that during an overflight of Nishinoshima conducted from 1335 to 1412 on 17 January surveyors observed continuous gray emissions rising from the central crater of the pyroclastic cone to 1.8 km (5,900 ft) a.s.l. and drifting E and NE. The central crater was open to the ENE; lava flows traveled NE and entered the ocean, producing steam plumes at the coastline.

Pacaya | Guatemala : INSIVUMEH reported that during 15-21 January Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 100 m above the crater rim, building a small cone. Multiple lava flows, some short-lived, traveled as far as 150 m W and S, and down the NW flank towards Cerro Chino.

Reventador | Ecuador : IG reported that during 15-22 January seismic data from Reventador’s network indicated a high level of seismic activity, including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions. Daily gas-and-ash plumes rose as high as 1.6 km above the crater rim and drifted W, NW, and N. Incandescent blocks rolled 700 m down the flanks. Weather sometimes prevented views of the summit area.

Santa Maria | Guatemala : INSIVUMEH reported that explosions at Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 800-900 m above the crater and drifted as far as 1.4 km W and SW. INSIVUMEH noted that ashfall was likely in areas downwind. Avalanches of material descended the NW, SW, and SE flanks of Caliente cone.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 10-17 January. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Shishaldin | Fox Islands (USA) : AVO reported that after almost a week of relatively quiet conditions at Shishaldin, during 16-17 January seismicity began to climb and the temperature of the thermal anomaly slightly increased. Activity intensified at 0030 on 19 January and by around 0630 the plume became more ash-rich. By around 0828 the ash plume rose to 6.1 km (20,000 ft) a.s.l. and drifted 150 km E, prompting AVO to raise the Aviation colour Code to Red and the Volcano Alert Level to Warning. Lava flows descended the NE and N flanks and generated lahars. By 1530 seismicity abruptly decreased, though around the same time the robust steam-and-ash plume (visible to pilots and in webcam and satellite images) rose as high as 9.1 km (30,000 ft) a.s.l. and continued to drift 150 km SSE. Minor amounts of ash fell in False Pass. Ash emissions had significantly declined by 2200 and seismicity was low; the Aviation colour Code was lowered to Orange and the Volcano Alert Level was lowered to Watch just after midnight the next morning. A detached volcanic cloud was identified in satellite images drifting ESE over the Pacific Ocean. During 20-21 January elevated surface temperatures were identified in satellite images, though the N-flank flow was not active. Seismicity remained above background levels, and coincided with detections in infrasound data that suggested small explosions at the vent. Steaming from the summit was visible in webcam images.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that Suwanosejima’s seismic network recorded an explosion at Ontake Crater on 10 January and occasional small eruptive events during 12-17 January. Plumes rose as high as 1 km above the crater rim. Residents of Toshima Village (4 km SSW) reported ashfall and explosion and rumbling sounds. The Alert Level remained at 2 (on a 5-level scale).

White Island | North Island (New Zealand) : On 22 January GeoNet reported that lava had been extruded into the vents created by the 9 December White Island eruption based on visual observations from the week before and on 21 January. Airborne gas measurements indicated high levels on 21 January and the vent temperature was very hot at more than 400 degrees Celsius. According to a news article another person died as a result from the eruption, bringing the total number of deaths to 20. The Volcanic Alert Level remained at 2 and the Aviation colour Code remained at Yellow.

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