Volcanos

Roundup of Global Volcanic Activity:

Shiveluch (Kamchatka): Activity has been elevated during the past days. Several explosions and / or dome collapse events have sent ash plumes to about 20,000 ft (6 km) elevation during the past days.

Sakurajima (Kyushu, Japan): Activity remains high - explosions occur at more-than-usual frequency from the Showa crater. An eruption on 27 July produced an ash plume rising to 18,000 ft (5.7 km) altitude, i.e. an eruption plume about 4.5 km tall.

Karangetang (Siau Island, Sangihe Islands, Indonesia): VSI has decreased the alert level from 3 (Siaga, Alert) (since 8 August 2011) back to 2 (Waspada, watch). No lava emissions/ejections have been observed since 7 July and seismic activity has been decreasing over the past weeks. No hot spot is visible on satellite imagery.

Ambrym (Vanuatu): A seismic swarm at the volcano was detected on 26 July, but no evidence of unusual activity at the surface has been detected. The lava lakes inside Benbow and Marum remain active.

White Island (New Zealand): The seismic crisis ended on 28 July with no eruption. Degassing remains elevated and incandescence is still visible from the dome in the crater.

Tungurahua (Ecuador): During the past days, a further increase in activity of the volcano occurred, characterized by the generation of large explosions and a constant ash eruption column, and several small to big explosions that generated strong vibrations and rattled windows in villages near the volcano. An eruption at 07:23 (local time) on 28 July generated a small pyroclastic flow that affected the upper north and north east flank of the volcano. Constant ash emissions produce a an ash column of up to 1.5 km height, drifting westwards. Ash fell in the town of Mocha.