Roundup of Global Volcanic Activity – Ongoing Activity for the week of 19 July – 25 July 2017
Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 23 July an ash plume from Bagana drifted W at an altitude of 2.1 km (7,000 ft) a.s.l.
Bezymianny | Central Kamchatka (Russia) : KVERT reported that during 14-21 July a thermal anomaly was identified daily over Bezymianny in satellite images. A lava flow continued to move down the W flank of the dome. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Bogoslof | Fox Islands (USA) : AVO reported that during 19-25 July no significant activity at Bogoslof was observed in cloudy or mostly cloudy satellite images, and no activity was detected in seismic, infrasound, or lightning data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.
Cleveland | Chuginadak Island (USA) : AVO reported that during 19-23 July elevated surface temperatures from Cleveland were identified in satellite images; no activity was observed in seismic, infrasound, or web-camera data although these data had been intermittent. On 21 July AVO noted that a new small lava dome, about 30 m in diameter and 10 m high, had appeared at the bottom of the summit crater within the previous week. The webcam recorded a weak steam plume rising from the summit crater on 25 July. 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 21-25 July ash plumes from Dukono rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted E and NE.
Karymsky | Eastern Kamchatka (Russia) : KVERT reported that explosions at Karymsky on 18 July generated ash plumes that rose 1.7 km (5,600 ft) a.s.l. Satellite images showed a weak thermal anomaly over the volcano during 18-20 July, and ash plumes drifting 117 km E on 20 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Kilauea | Hawaiian Islands (USA) : During 19-25 July 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. Several large cracks running parallel to the coastline spanned the width of the delta. Surface lava flows were active above the pali and on the coastal plain about 2 km upslope from the gravel emergency route.
Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 19-20 July a weak thermal anomaly over Klyuchevskoy was identified in satellite images, and ash plumes drifted 300 km SW, SE, E, and NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Nishinoshima | Japan : The Japan Coast Guard reported that visual observations of Nishinoshima from an aircraft during the afternoon of 11 July confirmed that the eruption was ongoing. Emissions from the center of the cone were grayish white and tephra was ejected. The lava flow on the W flank continued to enter the ocean. Based on a pilot observation the Tokyo VAAC reported that on 18 July an ash plume rose to 3 km (10,000 ft) a.s.l.
Poas | Costa Rica : OVSICORI-UNA reported that during 19-24 July plumes of magmatic gases, water vapor, and aerosols were emitted from Poás’s vent A (Boca Roja), and plumes of gases, water vapor, and abundant yellow particles of native sulfur rose from vent B (Boca Azufrada). Plumes rose 300-500 m above the vents and drifted W and SW.
Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that since the beginning of July there had been a gradual increase in activity at Sabancaya associated with rising magma and increased sulfur dioxide gas emissions. Gas-and-ash plumes rose to moderate heights, between 2.5 and 4.5 km above the crater rim. On 22 July winds shifted S and SE, causing ashfall in Lluta (30 km SW), Huanca (75 km SSE), and in some parts of Arequipa (80 km SSE).
Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily during 14-21 July in satellite images over Sheveluch. Based on video and satellite data explosive activity lasting about 8 hours on 24 July generated ash plumes that rose 11.5-12 km (37,700-39,400 ft) a.s.l. and drifted almost 700 km NE. Strong pyroclastic flows were also observed. The Aviation colour Code was raised to Red (the highest level on a four-colour scale). Later that day only steam-and-gas emissions with a small amount of ash were noted; the Aviation colour Code was reduced to Orange.
Sinabung | Indonesia : Based on PVMBG and pilot observations, satellite and webcam images, and wind data, the Darwin VAAC reported that during 19-25 July ash plumes from Sinabung rose 2.7-6.1 km (9,000-20,000 ft) a.s.l. and drifted in multiple directions.
Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that during 18-19 July ash plumes from Suwanosejima rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted E.
Turrialba | Costa Rica : OVSICORI-UNA reported that during 19-24 July plumes of water vapor, aerosols, and magmatic gases rose as high as 500 m above Turrialba’s crater rim, and on most nights incandescence emanated from Cráter Oeste. The emissions contained ash during 20-22 July. Minor ashfall was reported in Coronado (San José) on 20 July, and in Sabanilla de Montes de Oca (30 km WSW) on 22 July.