Aral Sea

Aral Sea ărˈəl [key], salt lake, SW Kazakhstan and NW Uzbekistan, E of the Caspian Sea in an area of interior drainage. To the north and west are the edges of the arid Ustyurt Plateau; the Kyzyl Kum desert stretches to the southeast. As recently as the 1970s it was the world's fourth largest lake, c.26,000 sq mi (67,300 sq km) in area and c.260 mi (420 km) long and c.175 mi (280 km) wide. Fed by the Syr Darya and Amu Darya rivers, it was generally very shallow, attaining a maximum depth of c.180 ft (58 m). In the 1950s the Soviet Union decided to cultivate cotton in the region, and since the early 1960s the Syr Darya and Amu Darya have been used for large-scale irrigation, causing a drop in the flow of freshwater into the sea. The sea is, as a result, now greatly reduced. Since 2009 the only areas of the lake permanently filled with water have been in extreme W and N portions of its former lakebed, about a tenth or less of its former size in area.

The sea formerly supported local fishing and was navigable from Moynaq (Muinak) to Aral. As the Aral has retreated from its former shores, due to the combined effects of evaporation and water diversion, major environmental problems resulted. The quality of the remaining water deteriorated as the concentration of salts and agricultural chemicals increased, increased salinity and toxicity killed the fish, and the health of those living along the shore suffered, in part from duststorms carrying contaminated former lakebed soil. Regional weather has been affected as well, becoming harsher as the sea's moderating climatic influence has diminished. Vozrozhdeniye, the site of a Soviet germ warfare waste dump, is a former island that is no longer isolated from the surrounding region; in 2002 the United States and Uzbekistan cleaned up the site.

Geologically separate from the Caspian Sea since the last Ice Age, the Aral Sea was once only slightly saline. Mentioned in Arab writings of the 10th cent., it was called the Khwarazm (or Khorezm) Sea by later Arab geographers. It was reached in the 17th cent. by Russians, who called it the Sinyeye More (Blue Sea). The United Nations has estimated that what remains of the sea will essentially disappear by 2020 if nothing is done to reverse its decline. The Kok-Aral Dam (completed 2005) was constructed to enclose the small northern section (in Kazakhstan), which has revived, but it is a fraction of the former sea, and further increases in the northern section's size are limited by the height of the dam. Portions of the former lakebed have been planted with salt-tolerant trees to stabilize the contaminated soil.

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