Satellites See Kasatochi Eruption

Volcano Erupts in Alaska’s Aleutian Island Chain August 7, 2008

Aug 8, 2008

An explosive eruption occurred at Kasatochi Volcano (52.18ºN, 175.51ºW) on the afternoon of August 7th, 2008, sending volcanic ash and gas 35,000 feet into the atmosphere

A volcano in Alaska’s Aleutian Island Chain, home to some of the world’s most dangerous volcanoes, has popped up on the radar screen at the Alaska Volcano Observatory (AVO). Satellite images from August 7th, 2008, show a large eruption cloud emanating from Kasatochi Volcano.

GOES Satellite Images of the Eruption

A loop of these images (provided by David Schneider, AVO), taken from NOAA’s Geostationary Operational Environmental Satellite (GOES), shows three distinct eruptions happening one after the other from August 7th 2300 UTC to August 8th 0530 UTC. The volcanic clouds are shown drifting to the southwest of the volcano. Earlier this summer, these same satellites detected an eruption from Alaska’s Okmok Volcano.

Earthquakes Warned of Activity

Days before the eruption of Kasatochi, the Alaska Volcano Observatory’s network of seismic instruments picked up an increase in seismic activity in areas near the volcano. Although no seismic networks are located on Kasatochi Volcano itself, networks located on neighboring island volcanoes can be used to pinpoint the source of activity. It was first undetermined what the exact source of these earthquakes could be. Earthquakes near volcanoes are caused by magma movement, but earthquakes near an island could also be the result of submarine activity.

Now that the Kasatochi volcano has erupted, scientists are more certain that these earthquakes are associated with volcanic activity. Moreover, AVO stated that a field crew from the U.S. Fish and Wildlife Service doing work on Kasatochi Island reported periods of continuous ground shaking lasting 5-10 minutes, numerous rock falls, and the strong smell of sulfur hours before the eruption.

The Kasatochi Volcano eruption is an excellent example of how satellite data are useful in monitoring volcanoes. Because there are so many volcanoes located in the Aleutian Island Chain – and the activity of these volcanoes is infrequent and irregular – it is not practical to commit millions of dollars of equipment and human resources to every volcano. Kasatochi Volcano has not been active in over a hundred years, and even reports of eruptions in the late 1800’s are difficult to confirm.

However, the current eruption exploded with enough intensity to send a cloud of gas and ash 35,000 feet into the atmosphere, making the eruption hazardous to aviation operations in the area. Subsequent satellite data of this eruption will assist scientists and the aviation community in helping aircraft to avoid this hazardous cloud. This especially highlights the need for earth-observing satellites to continue to help volcanologists all over the world monitor remote volcanoes and the unexpected hazards they can produce.

Sources:

Simon Carn, Personal Communication, Joint Center for Earth Systems Technology, University of Maryland, Baltimore Campus

David Schneider, Personal Communication, Alaska Volcano Observatory, U.S. Geological Survey

The copyright of the article Satellites See Kasatochi Eruption in Volcanoes is owned by Alexandra Matiella Novak. Permission to republish Satellites See Kasatochi Eruption in print or online must be granted by the author in writing.