Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 16 December 2020 – 22 December 2020

Aira – Kyushu (Japan) : JMA reported nightly incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 14-21 December and that the sulfur dioxide emission rate remained high. Four explosions were recorded during 16-18 December. One of the explosions, at 1959 on 17 December, generated a plume that rose 3 km above the crater rim and ejected bombs 1.3-1.7 km away from the crater. Another explosion, at 0439 on 18 December, produced a plume that rose 1.8 km and ejected bombs 1-1.3 km away from the crater. The Alert Level remained at 3 (on a 5-level scale).

Dukono – Halmahera (Indonesia) : Based on satellite and wind model data, the Darwin VAAC reported that during 18-19 December ash plumes from Dukono rose to 2.1 km (7,000 ft) a.s.l. and drifted SE and E. 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 15-17 December that sent ash plumes up to 3 km (10,000 ft) a.s.l. and drifted NE, SE, and S. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Etna – Sicily (Italy) : INGV reported that strong activity at Etna’s Southeast Crater (SEC) included fountaining and lava flows on 21 December. Tremor amplitude had gradually increased on 20 December but weather conditions prevented visual observations. During the morning of the 21st Strombolian activity occurred at three vents. By 0800 tremor amplitude suddenly increased, and by 1000 lava fountaining from at least two vents was observed in thermal camera images, along with an eruption plume to 3 km (10,000 ft) a.s.l. A lava flow emerged from the SW part of the cone, which had collapsed on 13 December, and traveled SW before branching W and E. A second flow from the NE side of the cone traveled E into the Valle del Bove. Lava fountaining ended around noon, with a simultaneous decrease in tremor amplitude. During the morning of 22 December a few small phreatic explosions were visible in webcam images, likely generated from the interaction of snow and lava. The front of the active SW flow reached 2,500 m elevation. By 1741 both flows were cooling down and no longer advancing.

Ibu – Halmahera (Indonesia) : PVMBG reported that at 1826 on 19 December an ash plume from Ibu rose 400 m above the summit 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.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was visible during 11-12 and 17 December. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Klyuchevskoy – Central Kamchatka (Russia) : KVERT reported that Strombolian and sometimes Vulcanian activity at Klyuchevskoy continued during 11-18 December and lava advanced down the Kozyrevsky drainage on the S flank. A large bright thermal anomaly was identified daily in satellite images. A steam-and-gas plume with some ash rose to 6 km (19,700 ft) a.s.l. and drifted 120 km NE on 13 December. The Aviation colour Code remined at Orange (the second highest level on a four-colour scale).

Nishinoshima – Japan : JMA reduced the exclusion zone for Nishinoshima from a radius of 2.5 to 1.5 km around the summit crater on 18 December; eruptive activity ended in August. Fumarolic and high-temperature areas remained visible.

Popocatepetl – Mexico : CENAPRED reported that each day during 16-22 December there were 112-231 steam-and-gas emissions from Popocatépetl, some of which contained minor amounts of ash. A gas, steam, and ash plume drifted SE on 22 December. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Reventador – Ecuador : IG reported that a high level of activity continued to be recorded at Reventador during 16-22 December; adverse weather conditions sometimes prevented visual conformation. Seismicity was characterized by 40-109 daily explosions, volcano-tectonic and harmonic tremor events, and long-period earthquakes as well as signals indicating emissions. Gas, steam, and ash plumes, observed sometimes multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 1 km above the summit crater and drifted mainly NW and W. Crater incandescence and incandescent blocks rolling 600 m down the NE and S flanks were observed nightly. The 450-m-long lava flow on the NE flank remained active but did not advance.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 16-22 December. Seismicity was characterized by 20-127 daily explosions, occasional harmonic tremor, long-period earthquakes, and signals indicating emissions. Weather clouds often prevented visual observations of the volcano, but the Washington VAAC and IG webcams recorded daily ash plumes that rose as high as 2.4 km above the summit and drifted mainly NW, W, and SW. Seismic signals signifying lahars were recorded during 16-18 December.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 11-18 December. On 22 December residents of Ust-Kamchatsk Village, 85 km SE, observed ash plumes rising to 8 km (26,200 ft) a.s.l. and drifting 42 km NE. The Aviation colour Code was raised to Red (the highest level on a four-colour scale). Just over an hour later ash plumes rose 6.5-7.5 km (21,300-24,600 ft) a.s.l. and drifted 130 km E; the Aviation colour Code was lowered to Orange.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported nighttime incandescence and intermittent eruptive activity at Suwanosejima’s Ontake Crater during 11-18 December. A total of five explosions were recorded, ejecting bombs up to 500 m away from the crater and producing gray-and-white plumes that rose 1.6 km above the crater rim. Ashfall was reported in Toshima village (4 km SSW). The Alert Level remained at 2 (on a 5-level scale).

Villarrica – Chile : POVI reported that four ash emissions at Villarrica were visible in webcam images on 16 December. SERNAGEOMIN stated that two ash pulses were associated with long-period (LP) events at 1146 and 1156 that same day; the first ash emission rose 160 m above the crater rim and drifted NW while the second rose 280 m and drifted 500 m NE. At 1716 on 17 December an ash emission associated with an LP event rose 720 m and drifted ESE. The Alert Level remained at Yellow, the second lowest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the municipalities of Villarrica, Pucón (16 km N), Curarrehue, and the commune of Panguipulli, and the exclusion zone for the public of 500 m around the crater.

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