Dust Storm Over the Aral Sea
Swirling brown sand colors over the green waters of the Aral sea in this recent MODIS Aqua image. The Aral Sea is a landlocked endorheic sea in Central Asia, between Kazakhstan in the north and Karakalpakstan to the south.
An Endorheic basin is a watershed from which there is no outflow of water from it; for example, no rivers, or underground flow, or diffusion through rock. Any rain that falls into it, remains there permanently, until it evaporates. These sorts of basins are more common in hot desert locations, though they can occur in any climate.
In the case of the Aral Sea, the rivers that feed it (the Amu Darya and Syr Darya) have been shrinking since the 1960s, as they were diverted by the Soviet Union for irrigation. The sea's surface area has shrunk by approximately 60%, and its volume by 80%. For more information on the Aral Sea, try reading the Wikipedia entry on it!
Besides the sandstorm covering the Aral Sea, also of note in this image are the two red dots, which represent active fires.