Eruptions

JMA reported that during 24-29 April white plumes from Asosan?s Nakadake Crater rose 200-800 m above the crater rim. Many low-amplitude tremors and volcanic earthquakes were recorded. Sulfur dioxide emissions were generally high but on 25 April the gas emissions were very high at 4,000 tons/day, a value not exceeded since 12 March. Emissions were 3,300 tons/day on 25 April. Weak incandescence from Nakadake Crater was visible at night during 27-28 April. The Alert Level remained at 2 (on a scale of 1-5).

Source: Japan Meteorological Agency (JMA)

KVERT reported that during 21-22 April a weak thermal anomaly over Klyuchevskoy was identified in satellite images along with gas-and-steam plumes containing ash drifting 160 km E. The Aviation Color Code was raised to Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

The Darwin VAAC reported that during 24-26 April white plumes of variable density rose 300-500 m above Tengger Caldera?s Bromo cone. White-to-black emissions rose 500 m above the cone on 27 April, and white-to-gray emissions rose 600 m above the cone on 29 April. The Alert Level remained at 2 (on a scale of 1-4), and visitors were warned to stay outside of a 1-km radius of the crater.

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

PVMBG reported that at 0534 on 30 April a dense gray ash plume from Agung rose 1 km above the crater rim and drifted E. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

JMA reported that incandescence from Minamidake crater (at Aira Caldera?s Sakurajima volcano) was occasionally visible at night during 22-29 April. Three events and one explosion during 22-26 April generated plumes that rose as high as 1.4 km above the crater rim. A small event was recorded on 27 April. The Alert Level remained at 3 (on a 5-level scale).

Source: Japan Meteorological Agency (JMA)

Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 24-27 and 29-30 April ash plumes from Dukono rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted in multiple directions. The Alert Level remained at 2 (on a scale of 1-4), and visitors were 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)

Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 21-22 and 24 April that sent ash plumes up to 2.5 km (8,200 ft) a.s.l. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

KVERT reported that a weak thermal anomaly over Karymsky was visible in satellite images during 18-21 April. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

PVMBG reported that there were 19 events during 22-28 April recorded by Anak Krakatau?s seismic network; no emissions from the events were visually observed, even though the visibility was a mix of clear and foggy conditions. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 2-km radius hazard zone from the crater.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

PVMBG reported that during 22-28 April the lava dome at Merapi continued to grow slowly, with any extruded material channeled into the SE-flank Gendol River drainage. White emissions rose 70 m. Five block-and-ash flows traveled as far as 1.2 km in the Gendol drainage on 24 April. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)