On February 21, 2007, a dust storm several hundred kilometers across clogged the skies over Algeria and Mali. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite took this picture the same day. This image shows the dust cloud over the Sahara Desert. As the dust is only slightly lighter than the sand below, the storm is easiest to discern in the east, over more variegated terrain.
The Sahara Desert ranks unsurprisingly among the world’s most dust-prone regions. Dust from this desert not only crosses national boundaries, but can also travel across the Atlantic Ocean to the Caribbean.