SPACEPHOTOS

The Aral Sea has shrunk to less than half its size since 1985. The Aral Sea receives little water (sometimes no water) from the two major rivers that empty into itthe Syr Darya and Amu Darya. Instead, the river water is diverted to support irrigation for the region extensive cotton fields. Recently, water scarcity has increased due to a prolonged drought in Central Asia. As the Aral Sea recedes, its former sea bed is exposed. The Aral sea bed is composed of fine sedimentsincluding fertilizers and other agricultural chemicalsthat are easily picked up by the region strong winds, creating thick dust storms. The International Space Station crew observed and recorded a large dust storm blowing eastward from the Aral Sea in late June 2001. This image illustrates the strong coupling between human activities (water diversions and irrigation), and rapidly changing land, sea and atmospheric processesthe winds blow across the Sea and pick up dust (former sea bottom sediments) as soon as the blowing air masses hit land. Note that the northern boundary of the dust storm occurs along the Syr Darya, where no bottom sediments are exposed.