Thermal signals from the volcano have been increasing over the past days, suggesting that the lava output at the summit crater has increased. This could again again to dangerous pyroclastic flows if the lava dome or lava flows become unstable on the steep upper flanks of the volcano. Such flows can easily reach inhabited areas.
During the past months (at least since May) the volcano has been constantly active with a weakly alimented lava flow on the upper southern flank, which has been generating frequent incandescent rock falls. It decreased during July, but a new phase of more violent activity might be in the making now and could make new evacuations necessary. Alert level of the volcano remains at 3 (out of 4).
August 19, 2015. Karangetang , Siau island , Indonésia :
Source : T Pfeiffer.
Photo : 04.2015 VSI Badan Geologi