In early August 2008, Okmok Volcano continued releasing a plume of volcanic ash. According to the Alaska Volcano Observatory (AVO), the volcano experienced a continuous volcanic tremor on August 4, 2008, along with continuing ash emissions.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image on August 4, 2008. A break in the clouds allows a clear view of the volcano, along with a hotspot—an area of unusually high surface temperature—at the summit. Compared to the image acquired by MODIS the previous day, the volcanic plume in this image is lighter in color and more diffuse in shape. The volcanic plume—likely a mixture of ash and steam—blends in with the clouds toward the southwest.
Okmok comprises the northeast end of Umnak Island in Alaska’s Aleutian Islands. It is a shield volcano with a low, broad shape that resembles an ancient warrior shield. The volcano has experienced intermittent activity since 1805.