Dust blew off Western Africa
A dust plume blew off the coast of western Africa on February 6, 2012. It was spanning hundreds of kilometers. Distinct plumes blow off the coast of Western Sahara over the ocean, but the large veil of dust in the southwest likely arose farther inland. Sandy desert covers most of Mauritania, and those sand seas may have provided the material for most of the dust in this image. The clouds in the southeast are part of a large cloudbank stretching over western Africa. This large cloudbank could be associated with the weather pattern that blew the dust off the coast.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite took this picture the same day. West of Mauritania, the dust is thick enough to hide the ocean surface below. Part of the Cape Verde archipelago dimly shows through the plume. Clouds floating overhead cast their shadows on the dust. (EarthObservatory)
Is this very unusual?