On September 16, 2010, dust blew off the west coast of Africa for the second consecutive day. Captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite, this natural-color image shows two dust plumes.
The northern, lighter plume blows off the coast of Western Sahara. The southern, darker plume blows off the coast of Mauritania. The long southern plume forms a dusty arc spanning hundreds of kilometers. Along its southern margin, it grazes Cape Verde as it mixes with clouds.
Source points for the dust storm aren’t clear in this image, but the different colors of dust might result from different points of origin, such as one or more of the sand seas in Mauritania.