Volcanos

Roundup of Global Volcanic Activity:

Sakurajima (Kyushu, Japan): The volcano remains in a state of elevated activity. Ash emission and explosions have been occurring with no break when observed from nearby during the past night: The volcano constantly emitted dilute to dense ash plumes in the form of both steady plumes or in single puffs. The ash emissions occurred in long-lasting phases that were either completely silent or, more often, accompanied by weak to loud hissing and roaring sounds of degassing that swell and decrease in pulses, resembling the sound of airplane turbines. It appears that this activity corresponds to deep-seated strombolian activity. At night, faint glow could sometimes be seen at the crater during the emissions.

Kelimutu (Flores): The alert level of the volcano has been placed back to green (normal) by the Indonesian Volcanological Survey. The increased evaporation and the change of colour of two of the three crater lakes, that had prompted the raise in alert status in June, have returned to normal levels or been reverted in July, suggesting that the crisis of the volcano is over. Monitored parameters as seismic and degassing activity have decreased back to normal levels.

Popocatépetl (Central Mexico): Activity has remained stable, with an average of about 2 emissions per hour of mostly low intensity. No larger explosions have occurred since the past update. Bright glow from the crater and a significant SO2 plume indicate that magma continues to rise within the volcano. Although activity is back to levels comparable to most of the previous months, the alert level remains at Yellow phase 3 (but might be soon lowered again to phase 2).

Turrialba (Costa Rica): A significant earthquake swarm has started late on 13 July at the volcano and is continuing. This could indicate a rise of magma in progress and eventually lead to new eruptions in the near future.

Tungurahua (Ecuador): A large explosive eruption occurred Sunday (14 July) morning, producing a large ash plume that could be seen from Quito (135 km away) and pyroclastic flows. According to Washington VAAC, the ash reached altitudes of 45,000 ft (13 km). The eruption followed a fast build-up of seismic activity, and likely corresponds to a vulcanian-type explosion, where pressure builds up to eject a solid plug that has tapped the vent. Elevated seismic activity had been noted in phases at the volcano during the previous weeks and while not completely unexpected as a potential scenario, the strength of the explosion was a surprise. The threat and hazard of new pyroclastic flows prompted the government to evacuate people living nearest to the volcano.