An underwater volcano in the South Pacific nation of Tonga with a history of creating short-lived islands is growing again toward the ocean surface. Metis Shoal has throughout recorded history created lava domes, pumice rafts and small islands that are eventually eroded by waves. It spawned a huge pumice raft in August that made headlines when sailors encountered it. The volcano has since been observed causing plumes of steam to rise above the Pacific.
Global Volcanic Activity – Ongoing Activity for the week of 16 October – 22 October 2019
Aira | Kyushu (Japan) : JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible at night during 15-21 October. There were 14 explosions and seven non-explosive eruptive events detected by the seismic network. Eruption plumes rose as high as 3 km above the crater rim and large blocks were ejected as far as 1.3 km away. The sulfur dioxide emission rate was high, at 2,800 tons/day, on 15 October. The Alert Level remained at 3 (on a 5-level scale).
Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 16-22 October ash plumes from Dukono rose to altitudes of 2.1-2.3 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions. 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 11-18 October that sent ash plumes up to 4 km (13,100 ft) a.s.l. Ash plumes drifted NE, causing ashfall in Severo-Kurilsk on 15 October. A weak thermal anomaly was identified in satellite images on 12 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Etna | Sicily (Italy) : INGV reported that during 14-20 October diffuse ash plumes from Etna’s Northeast Crater (NEC) varied from quickly-dispersing puffs to emissions lasting several hours. Ash drifted S, producing ashfall in areas downwind including Pedara, Mascalucia, Nicolosi, San Giovanni La Punta, and Catania. Ash plumes also rose from Voragine Crater (VOR).
Ibu | Halmahera (Indonesia) : PVMBG reported that at 0829 on 20 October an ash plume from Ibu rose at least 400 m above the summit and drifted W. 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.
Karangetang | Siau Island (Indonesia) : PVMBG reported that during 14-20 October 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. Incandescence from both summit craters was visible at night. Sometimes dense white plumes rose to 600 m above the summit. According to the Darwin VAAC minor ash plumes were visible in satellite images rising to 2.4 km (8,000 ft) a.s.l. (600 m above the summit) and drifting W and NW. The Alert Level remained at 2 (on a scale of 1-4).
Krakatau | Indonesia : PVMBG reported that during 14-20 October Anak Krakatau’s seismic network recorded 24 eruptive events. Diffuse white plumes rose as high as 150 m above the vent. A webcam on the volcano recorded several eruptions that ejected dense, blackish-gray ash plumes 150-300 m above the crater floor. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.
Merapi | Central Java (Indonesia) : PVMBG reported that an eruption at Merapi at 1631 on 14 October generated an ash plume that rose 3 km above the summit and caused ashfall in areas as far as 25 km SW. A pyroclastic flow traveled 2 km down the Gendol drainage on the SW flank. The event changed the shape of the dome by removing a NE-SW trending section that was 100 m long, 30 m wide, and 20 m deep. Lava continued to extrude during 14-20 October, generating at least two block-and-ash flows that traveled 1 km down the Gendol drainage. Foggy conditions sometimes prevented visual observations. White emissions rose as high as 500 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to stay outside of the 3-km exclusion zone.
Semeru | Eastern Java (Indonesia) : The Darwin VAAC reported that on 18 October an ash plume from Semeru rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted W based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4).
Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 11-18 October. Explosions during 11-13 and 15 October produced ash plumes that rose 6.5-7 km (21,300-23,000 ft) a.s.l. and drifted 620 km E and SE. Resuspended ash drifted 125 km E during 16-17 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).
Shishaldin | Fox Islands (USA) : On 17 October AVO raised the Aviation colour Code for Shishaldin to Orange and the Volcano Alert Level to Watch noting that new lava effusion in the summit crater had begun on 13 October. Weather clouds had mostly prevented views of the crater during 12-18 October; elevated surface temperatures were detected during 13 and 17-20 October. A steam plume was visible in webcam images on 19 October.
Tangkubanparahu | Western Java (Indonesia) : Diffuse white water-vapor plumes rose 40 m above the vent on Tangkubanparahu’s Ratu Crater floor during 14-21 October. PVMBG lowered the Alert Level to 1 (on a scale of 1-4) on 21 October, noting that phreatic events had not been recorded for the past month, deformation data indicated no rising magma, and other data all suggested decreased activity. Tourists were advised to avoid going into the crater.