Kasatochi Volcano is one of many mostly submarine volcanoes whose summit emerges from the waters of the Bering Sea off the southwest coast of Alaska. After earthquakes and other seismic activities starting on or around August 7, Kasatochi began erupting large plumes of ash and gases. On August 8, 2008, skies were cloudy when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite passed overhead and captured this natural-color image. The bright clouds provided good contrast for the volcanic plume, which is dark brown.
The ash plume spread southeastward from the volcano over the Pacific Ocean. Weather patterns caused the plume to diffuse as it swirled counterclockwise. Beneath the plume, which is dark brown, a few breaks in the clouds reveal that the normally deep blue waters of the Pacific are turquoise-colored. This brightness may be the result of ash or rocks debris settling on the water’s surface. According to an article in an Anchorage newspaper, the ash cloud forced cancellation of scores of flights into and out of Alaska, stranding as many as 6,000 passengers.
After earthquakes and other seismic activity starting on August 7, 2008, Kasatochi Volcano began erupting large plumes of ash and gases in subsequent days. Over the following week, the plume of sulfur dioxide spread across Canada and the Northeast United States.