Volcanos

Roundup of Global Volcanic Activity:

Klyuchevskoy (Kamchatka): The volcano remains active. It produces a variable but often intense steam plume with possibly some ash. On webcam images, there are sporadic small explosions visible, suggesting that weak strombolian activity continues at the summit. A large steam ring was produced this morning.

Aso (Kyushu): The Japan Meteorological Agency reported in its latest activity summary (for September 2013) a seismic crisis that started on 23 September evening. An survey of SO2 emissions 2 days later showed an increase of gas release as well, suggesting a magmatic intrusion was taking place. No eruption has taken place since then. Japanese volcanologists immediately raised the alert level from 1 to 2, as there is a possibility of sudden explosions that could throw blocks to distances of perhaps as far as 1 km. The new alert level means that the active Nakadake 1 crater is currently closed for access. In late September seismicity remained high, but with a declining trend. No other information was given in the report.

Sakurajima (Kyushu, Japan): The volcano has picked up activity again. Over the past days, the Showa crater has been producing near-constant ash emissions and several vulcanian explosions with ash plumes rising up to 14,000 ft (4.2 km) altitude.

Bagana (Bougainville Island, Papua New Guinea): Explosions continue. An ash plume was spotted this morning at 9,000 ft (2,7 km) altitude extending 60 nautical miles to the west.

Sinabung (Sumatra, Indonesia): Eruptions seem to increase. Over the past days, ash explosions have occurred at rates of 1-2 per day. Ash plumes rose to 10,000-12,000 ft (3-3.6 km) altitude. At least one pyroclastic flow occurred on 11 Nov, reaching about 1 km length. Several 1000 people have been evacuated from nearby villages at the foot of the volcano and a (dangerously small) 3 km exclusion zone around the volcano is in place.

Popocatépetl (Central Mexico): Activity has remained stable at low levels. CENAPRED reported 61 weak emissions of mostly steam, gas and only occasionally minor amounts of ash during the 24 hour observation interval between 12-13 Nov.

Reventador (Ecuador): The activity consisting of sporadic small to moderate explosions continues but has decreased after 2 November. On that day, a small pyroclastic flow descended on the west flank of the active cone, reaching a length of 300-400 m. Explosions produced plumes of up to about 2 km height and light ash fall occurred in San Rafael village located 8 km east of the volcano.

Jebel Zubair (Red Sea): Signs of weak continuing or renewed activity could be spotted again on recent satellite data after few weeks with no evidence of activity. The MODIS / Terra satellite image from 11 Nov shows a gas plume drifting NE from the new island as well as a discoloured water plume extending south. The discoloured sea water is likely caused by dissolved volcanic gasses (H2S in particular). The absence of steam suggests that there is no lava entering the sea and no submarine effusive activity.

Heard (Australia, Southern Indian Ocean): A thermal hot spot was visible on satellite data from 9 Nov, suggesting that some activity continues or has resumed at the remote volcano.