By May 26, 2010, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this photo-like image, Iceland’s Eyjafjallajökull Volcano had slowed its eruption. A tiny, white puff of steam rises from the volcano in this image. Considerable steam had been coming from the crater, said the Icelandic Met Office, but monitoring the eruption became difficult because of windblown ash. The problem is illustrated here. Two broad swaths of tan ash, many kilometers across, obscure the Icelandic coastline and sweep over the Atlantic Ocean.
The ash resembles an eruption plume in color, but it is actually resuspended ash. During Eyjafjallajökull’s eruption, fine powdery ash fell around the volcano and on areas downwind. The ash still rests lightly on the land’s surface and is easily lifted in the wind. On May 26, winds blew toward the south, southeast, picking up a thick cloud of ash near the volcano.
The ash is blowing over the North Atlantic Ocean. The ocean itself is colored with subtle swirls of blue and green, revealing the presence of a large phytoplankton bloom. While volcanic ash can fertilize ocean waters in parts of the world where waters contain little iron, the North Atlantic already contains more than enough iron to sustain large phytoplankton blooms. This bloom is part of the large phytoplankton bloom that covers much of the North Atlantic every spring and summer.
The large image is the highest-resolution version of the image. The image is available in additional resolutions from the MODIS Rapid Response System.
Sveinbjörnsson, H., Arason, T., and Hreinsdóttir, S. (2010, May 26). Eruption in Eyjafjallajökull. (pdf) Icelandic Meteorological Office and Institute of Earth Sciences, University of Iceland. Accessed May 26, 2010.