This page contains archived content and is no longer being updated. At the time of publication, it represented the best available science.
This series of images shows a dust plume obtained from Total Ozone Mapping Spectrometer
(TOMS) data over the Sahara Desert and extending over the Atlantic Ocean and Canary Islands. The land sources of the dust plume are clearly visible, with the main source coming from Western Sahara and Mauritania. The green to red false colors in the dust plume image represent increasing amounts of aerosol, with the densest portion over the ocean. Under the densest portions of the dust plume (red) the amount of ultraviolet sunlight is reduced to half its normal value. Between February 27 to February 29 the ocean dust plume decreases while a massive dust plume develops over the land that covers a region from the equator to 30° N latitude. Based on previous dust events observed by
TOMS, there should be another dense plume over the ocean during the next few days.
A thick plume of dust blew off the coast of Mauritania in western Africa on October 2, 2007. In this image, the dust varies in color from nearly white to medium tan. The dust plume is easier to see over the dark background of the ocean, but the plume stretches across the land surface to the east, as well.