Mount Redoubt, AlaskaMay 5th, 2009 at 8:45 pm by Patrick Powell under Weather
Mount Redoubt in Alaska will likely erupt soon. To geologists, soon means in a few minutes or in the next few years. But judging by the wording used by the AVO (Alaskan Volcano Observatory) it could be the next few days.
Here is the latest update from the AVO this afternoon “Seismic activity remains at an elevated level at Redoubt Volcano, and the lava dome in the summit crater continues to grow. An explosive event due to dome collapse, from instability of the growing dome, or due to internal depressurization could occur at any time. An explosion may produce a high altitude (>30,000 ft ASL) ash plume, trace to minor ash fall in parts of south-central Alaska, lahars in the Drift River valley, and pyroclastic flows in the immediate vicinity of the volcano. AVO continues 24/7 operations and is monitoring the situation closely.”
The use of “explosive event” and “instabilaty of a growing lava dome” is pretty strong wording for volcanologists, and it appears they are anticipating something fairly intense and in short order. One of the webicorders (siesmigraphs) on the flank of the mountain has been showing nearly constant rumbling with some larger spikes. This is generally interpreted as magma (lava) moving up toward the surface, and the AVO has also been monitoring the growth of the lava dome. The AVO does an outstanding job of tracking the volcanoes across Alaska and this volcano is being extensively documented.
On a side note, volcanism especially in the high latitudes can have an impact on weather throughout the northern hemisphere. The size of the eruption will determine the amount of impact, but a VEI (Volcano Explosivity Index) 6 would have a definite cooling impact on Wisconsin for about a year and would likely create extrodinary sunsets through the summer. Mount Redoubt is a stratovolcano and has had a few major eruptions in the past. Smithsonian Weekly Volcano Report It is also worth noting that there are currently 26 Volcanoes worldwide in some state of eruption. Nearly all are weak at this time and that is not unusual, included in that list of 26 is Chaiten in Chile which initially erupted last year with an explosive outburst.