Dust Plumes Off Libya
Two-toned dust plumes blew northward off the coast of Libya on October 26, 2007, as the MODIS on NASA's Terra satellite took this picture. While plumes in the west are beige, reminiscent of the Sahara's sands, the plumes in the east are distinctly darker. The differences in color can be traced to the varied origins of the plumes.
In northeastern Libya, where the land projects northward into the Mediterranean Sea, the land surface differs from the inland desert. This area contains the Akhdar Mountains, and the coastal plain north of these mountains contains light, fertile soils. Not only is this difference in land cover discernible when skies are clear and winds are calm, it is also apparent when dust blows off the coast. Like the soils where they originate, plumes from the coastal plain are darker than those from the inland desert.