Geography H/W – The Disappearing Aral Sea
This essay intends to first introduce the disappearing Aral Sea, which due to the extensive agricultural activities devised by the Soviet government in the region, the former fourth-largest lake of the world is now the world's eighth largest lake. This has resulted in perhaps the world's most prominent man-made ecological disaster, giving its location and background knowledge with a map, and then describe its future in terms of how it is going to be utilized and what the consequences are, and then finally state what can be done about this “crisis”. @.
The Aral Sea is located in the Central Asian Republics of Uzbekistan and Kazakhstan. Due to its location in the center of a vast mainland far from oceans, the Aral Sea maintains a continental climate. Temperatures in the region go up as high as 40 degrees Celsius in the summer and in winters the temperature falls down to -20 degrees Celsius with minimal precipitation. The main volume of surface waters is consisted of thawed water from high glaciers, feeding the two recently largest rivers of the region: the Amu Darya (Located in Eastern Central Asia, 2580 km long) and the Syr Darya: (2,220 km long).
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, mainly occupying three basins in the central, western, and northern sections of its lakebed. It is about a third of its former size in area and less than an eighth in volume.
The sea formerly supported local fishing and was navigable from 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 have resulted. The quality of the remaining water has deteriorated, increased salinity has killed fish, and the health of those living along the shore has suffered. 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 2001 the United States agreed to help clean up the site.
Geologically separate from the Caspian Sea since the last Ice Age, the Aral Sea was once only slightly saline. The United Nations has estimated that the sea will essentially disappear by 2020 if nothing is done to reverse its decline, but in 2003 construction began on a dike to enclose the smaller northern section, in an attempt to revive at least that.
The drying up of the Aral Sea is also negatively affecting the region's climate. Earlier, the Aral Sea acted as a climate regulator for the region: it softened cold Siberian winds in winters and acted as a conditioner lowering heat in summer months. The sea's shrinkage has resulted in drier and shorter summers, and in longer and colder winters. The growing season has been shortened to 170 days (while 200 is necessary for cotton production). Precipitation on shore in the Aral region has decreased by a factor of 10, the humidity of air has decreased by 10%, summer temperatures have increased and winter temperatures decreased by + 2-3 degrees centigrade. The productivity of pasture-grounds half its previous level. The pollution effect is aggravated by the fact that the Aral Sea is situated on the "highway" where strong currents of air are blowing from the West to the East. This promotes carrying up of aerosols to higher layers of atmosphere and spreading of them around the Earth. That is why pesticides from the Aral region are found out in blood of penguins in the Antarctic Continent. The distinctive Aral dust is falling on glaciers of Greenland, on forests of Norway,...
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