A long line of Sahara dust swept across Mali, Mauritania, and Western Sahara and out over the Canary Islands on March 3, 2004. The dust appears to have originated in Algeria. Winter and spring dust storms are common in Western Africa when the sirocco winds, hot, dry, dust-laden winds, blow north and northwest out of the Sahara desert. This image was taken by the Terra satellite. Later on the same day, the Aqua satellite recorded a similar scene. As the day progressed, the dust grew thicker and the storm extended farther west.
The high resolution image provided above is at MODIS’ maximum resolution of 250 meters per pixel. The scene is available in additional resolutions.