Dukono (Indonesia) – Report for 28 August-3 September 2019

Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 28 August-3 September ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 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.

Sources: Darwin Volcanic Ash Advisory Centre (VAAC),Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

Ebeko (Russia) – Report for 28 August-3 September 2019

KVERT reported that a thermal anomaly over Ebeko was identified in satellite images on 23 August.
Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E, observed explosions during 27-28 August that sent ash plumes up to 3 km (10,000 ft) a.s.l. and drifted E. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

AVO Cleveland YELLOW/ADVISORY – Unrest continues; satellite observations obscured by clouds.

Sep 10, 2019 20:12 – Satellite images show highly elevated surface temperatures in the summit crater during periods of good weather over the past day. Local seismic data is out but no activity was detected by regional seismic data or infrasound arrays during the last 24 hours.

Episodes of lava effusion and explosions can occur without advance warning. Explosions from Cleveland are normally short duration and only present a hazard to aviation in the immediate vicinity of the volcano. Larger explosions that present a more widespread hazard to aviation are possible, but are less likely and …

AVO Semisopochnoi ORANGE/WATCH – Seismicity remains elevated.

Sep 10, 2019 20:12 – Low-level eruptive activity may be continuing at Semisopochnoi. Seismic activity over the past day remains elevated with low-frequency earthquakes but there were no explosions detected in regional infrasound data. Satellite observations were mostly obscured by clouds over the past day.

Semisopochnoi is monitored with an on-island seismic network and remotely by satellite and lightning sensors. An infrasound array on Adak Island may detect explosive emissions from Semisopochnoi with a slight delay (approximately 13 minutes) if atmospheric conditions permit.

AVO Shishaldin ORANGE/WATCH – Low-level eruption continues; elevated surface temperatures observed in satellite

Sep 10, 2019 20:12 – Low-level eruptive activity continues at Shishaldin volcano. Seismicity remains elevated with steady tremor detected over the past day. Satellite images show highly elevated surface temperatures in the summit crater, Clear web camera images from this morning show no evidence of hot deposits on the upper flank as suggested by satellite data from yesterday.

Shishaldin is monitored by local seismic and infrasound sensors, satellite data, a web camera, a telemetered geodetic network, and distant infrasound and lightning networks.

Asamayama (Japan) – Report for 21 August-27 August 2019 – NEW

JMA reported that at 1928 on 25 August a small eruption at Asamayama generated a grayish-white ash plume that rose 600 m above the crater rim and drifted E. Large blocks were also ejected from the crater. Minor ashfall was reported in Karuizawa Town, Nagano Prefecture, about 4 km E. The plume then turned white and continuous emissions rose 200 m during 25-26 August. The Alert Level remained at 2 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)

Shishaldin (United States) – Report for 21 August-27 August 2019 – NEW

AVO reported that during 21-28 August continuous, low-level tremor at Shishaldin was recorded by the seismic network and elevated surface temperatures were often visible in satellite images. The spatter cone in the crater had grown and partially filled the summit crater. NOAA scientists took video of the eruption during an overflight on 17 August and noted repetitive minor explosive activity within the summit crater. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.

Source: US Geological Survey Alaska Volcano Observatory (AVO)