Volcanos

Roundup of Global Volcanic Activity - Ongoing Activity for the week of 30 August - 5 September 2017

Aira | Kyushu (Japan) : JMA reported that six explosive events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 28 August-4 September ejected material as far as 800 m. Ash plumes rose as high as 2.2 km above the crater rim. Crater incandescence was observed at night. The Alert Level remained at 3 (on a 5-level scale).

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 31 August ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted N, W, and SW.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 28-30 August a thermal anomaly over Bezymianny was identified in satellite images. A lava flow continued to flow down the W flank of the dome; incandescence from the dome was visible at night. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Bogoslof | Fox Islands (USA) : AVO reported that an explosive event at Bogoslof began at 0405 on 30 August and continued intermittently until 0555; the event produced a low-level ash plume that rose to around 6.1 km (20,000 ft) a.s.l. and drifted SSE. Later that day seismic and infrasound data showed quiet conditions, and a low-level plume (likely steam) drifted almost 65 km SSE. Satellite, infrasound, and seismic data showed nothing notable during 31 August-5 September. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that elevated surface temperatures at Cleveland were identified in satellite data during 29-30 August and 4-5 September; cloudy weather sometimes prevented satellite and webcam observations. Small vapor plumes from the summit was observed in webcam images during 30-31 August. Nothing noteworthy was detected in seismic or infrasound data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 30 August-1 September and 3-5 September ash plumes from Dukono rose to altitudes of 1.5-2.4 km (5,000-8,000 ft) a.s.l. and drifted SW, W, and NW.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 28-29 August generated ash plumes that rose as high as 2.2 km (7,200 ft) a.s.l. Minor amounts of ash fell in Severo-Kurilsk on 28 April. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT noted gas-and-steam emissions at Karymsky since 12 August. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale) on 30 August.

Kilauea | Hawaiian Islands (USA) : During 30 August-5 September HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from long-active sources within Pu'u 'O'o Crater. The 61G lava flow, originating from a vent on Pu'u 'O'o Crater's E flank, continued to enter the ocean at Kamokuna. Surface lava flows were active above the pali and on the coastal plain. Slumping of seaward portions of the delta continued, and cracks running parallel to the coastline continued to widen. HVO warned of the potential for larger-scale delta collapses.

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite data, KVERT reported that ash plumes from explosions at Klyuchevskoy rose 6 km (19,700 ft) a.s.l. and drifted 550 km in multiple directions during 24-25 and 30 August. On 6 September KVERT noted that activity had decreased and that there was snow on the flanks; ash emissions were last observed on 30 August. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 1-2 September ash plumes from Langila rose 1.8 km (6,000 ft) a.s.l. and drifted N and NW.

Manam | Papua New Guinea : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 2 September an ash plume from Manam rose 2.1 km (7,000 ft) a.s.l. and drifted NNW.

Nishinoshima | Japan : The Japan Coast Guard reported that visual observations of Nishinoshima from an aircraft during the afternoon of 11 August suggested that the eruption was continuing; a high temperature area at the ocean entry on the W flank and a steam plume indicated flowing lava. Lava in the central crater could not be confirmed; a small fumarolic emission rose from the crater’s edge. Observations on the afternoon of 24 August suggested no lava flowing into the ocean.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; there was an average of 44 explosions recorded per day during 28 August-3 September. The earthquakes were dominated by long-period signals, with fewer numbers of hybrid events and signals indicating emissions. Gas-and-ash plumes rose 3.2 km above the crater rim and drifted no more than 40 km SE and S. The MIROVA system detected five thermal anomalies. The report warned the public not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified daily in satellite images during 25 August-1 September. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : Based on observations by PVMBG and the Jakarta MWO, satellite images, and wind data, the Darwin VAAC reported that during 31 August-1 September ash plumes from Sinabung rose 3.3-4 km (11,000-13,000 ft) a.s.l. and drifted WSW, NW, and ENE.

Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported explosions during 30 August-2 September.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 0820 on 5 September generated a plume that rose 400 m above the crater rim and drifted NW. Another event at 1550 that same day produced a plume that rose 500 m and drifted SW.

Ulawun | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 31 August-1 September and 5 September ash plumes from Ulawun rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SW, W, NW, and N.