Roundup of Global Volcanic Activity – Ongoing Activity for the week of 15 February-21 February 2017
Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery, the Darwin VAAC reported that during 16 and 18-20 February ash plumes from Bagana rose to altitudes of 2.4-3.4 km (8,000-11,000 ft) a.s.l. and drifted SSE, S, and SW. Ash plumes drifted as far as 85 km during 19-20 February.
Bogoslof | Fox Islands (USA) : AVO reported that during 15-16 February cloud cover prevented satellite views of Bogoslof; no other data indicated eruptive activity. At 0955 on 17 February seismic data indicated the beginning of an explosive event, prompting AVO to raise the Aviation Colour Code (ACC) to Red and the Volcano Alert Level (VAL) to Warning. Individual pulses of seismicity was recorded until 1140, and then afterwards seismicity was low. Satellite images and pilot observations indicated that an ash plume rose to an altitude of 11.6 km (38,000 ft) a.s.l. The event was also verified by infrasound and lightning data. Another short-lived explosive event began at 1546, detected in infrasound and seismic data. A volcanic cloud identified in satellite images rose as high as 7.6 km (25,000 ft) a.s.l.
An explosion at 0450 on 18 February was detected in seismic, infrasound, and lightning data. The seismic data suggested that ash emissions lasted several minutes, and then seismicity decreased. A preliminary evaluation of satellite data indicated that a cloud rose at least as high as 7.6 km (25,000 ft) a.s.l.; the cloud drifted SW. On 19 February the ACC was lowered to Orange and the VAL was lowered to Watch. Later that day seismic and infrasound data recorded a series of short-lived explosive pulses during 1708-1745. The ACC was raised to Red and the VAL was raised to Warning. A plume identified in satellite images rose as high as 7.6 km (25,000 ft) a.s.l. and drifted 160 km SE over Unalaska Island. AVO geologists on the island described the cloud has having a white upper portion and a slightly darker lower portion. Storms in the region impacted data communications at AVO’s facility in Dutch Harbour on 20 February, limiting AVO’s ability to forecast and detect eruptions at Bogoslof.
Cleveland | Chuginadak Island (USA) : AVO reported that although weather clouds mostly prevented satellite and webcam views of Cleveland during 15-21 February, slightly elevated surface temperatures were identified in satellite imagery during 18-19 February. The Aviation Colour Code remained at Orange and the Volcano Alert Level remained at Watch.
Colima | Mexico : Based on Centro Universitario de Estudios e Investigaciones de Vulcanologia – Universidad de Colima observations, the Unidad Estatal de Protección Civil de Colima reported that during 10-16 February there were 10 low-intensity explosions at Colima. Gas emissions were at low-to-moderate levels. The report noted that the public should not enter the 8-km-radius exclusion zone.
Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 14 and 16-21 February ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions.
Kilauea | Hawaiian Islands (USA) : During 15-21 February HVO reported that the lava lake continued to rise and fall, circulate, and spatter in Kilauea’s Overlook vent. Webcams recorded incandescence from long-active sources within Pu’u ‘O’o Crater and from a vent high on the NE flank of the cone. All surface flows were active within 2.4 km of Pu’u ‘O’o. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna.
Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and wind data, the Darwin VAAC reported that during 17-18 February ash plumes from Langila rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted SE.