Sinabung (Sumatra, Indonesia): The alert level of the volcano was again raised from "siaga" to "awas", the highest on the Indonesian 1-4 scale. The reason is a currently elevated risk of possibly larger pyroclastic flows, that could be triggered by collapse of the increasing volume of the viscous lava lobe emplaced on the upper SE flank. The alert level of the volcano had been at 4 during late Nov 2013 until April 2014,- the first and so far most violent phase of pyroclastic flow generation after the lava had spilled over the summit crater and built a large lobe that reached the base of the cone. Since then, for more than a year now, lava effusion has continued at mild, more or less constant rate. Tremor data suggest that the supply rate of magma to the volcano's summit has been more or less constant during the past year. This activity produced successive lava lobes on the upper flank, all on top and/or at the upper sides of the main flow emplaced during the first months of the eruption. Associated avalanches and pyroclastic flows had mostly been smaller in comparison, although a few larger ones occurred as well.
Ambrym (Vanuatu): (3 Jun) The lava lakes on Ambrym remain very active. As to visiting the island and the aftermath of Cyclone Pam, our partners on location (guides, porters etc) confirmed us that expeditions to Ambrym and Vanuatu in general can again run with no obstacles.
Cotopaxi (Ecuador): (3 Jun) The volcano has been showing signs of unrest. Since mid-April this year, and particularly during May, a marked increased in earthquakes and SO2 emissions have been detected, which could be signs of a magma intrusion beneath the volcano. During May, about 3000 local earthquakes were recorded, a significant increased compared to April (628 quakes), and more than during the last seismic crisis in 2001-02. In particular, long-period earthquakes related to internal fluid movements have shown an increase in May. Most quakes were located in areas north and northeast of the volcano's summit, at two depth layers, one at shallow 3 km and others at deeper depths of up to 14 km. In addition, SO2 emissions have shown an increased from normal values of approx. 500 tons / day to 2500-3000 tons per day. At the crater, fumarolic activity has increased during May. During the weekend of 22 and 23 May, sulphur smell the upper northern flank was very intense.
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