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The Aral Sea An Ecological Disaster Where in the World? 1964 1964 1973 1964 1973 1987 1964 1973 1997 1987 1964 1973 1999 1987 1997 1964 1987 Over the past 30 - 1973 40 years there has been a loss of more than 60% of the lake's water. The 1999 lake has shrunk from over 65,000 sq km to less than half that size, exposing large areas of the lake bed. From 1973 to 1987 the Aral dropped from fourth to sixth among the world's largest lakes. 1997 1964 1973 The Aral, once the world's fourth-largest lake, has lost 90 percent of its source waters and half its surface area. 1999 1987 1997 2003 How did this happen? For more than 30 years, water has been diverted from the Amu-Darya and the SyrDarya Rivers feeding the Aral, to irrigate millions of acres of land for cotton and rice production in Central Asia. How did this happen? By 1960 water diverted from rivers that feed the Aral Sea irrigated 11 million acres, most of it former desert, producing enough cotton to make the Soviet Union a net exporter. Today, these rivers irrigate 20 million acres, extending as far as China to the east and Afghanistan to the south. What are the Hydrological Consequences? The lake's salt concentration increased from 10% to more than 23%, obliterating twentyfour species of fishes that once thrived there. Ships lie abandoned on salt-encrusted seabeds, and fishing villages are now far from water. What are the Climatological Consequences? The local climate has shifted. Desert land has spread; wetlands have dried up; and sandstorms, stirring up pesticide-laden dust, are more common. Summers are hotter and dryer, winters colder, growing seasons shorter. What are the Health Consequences? As the water retreated, salty soil remained on the exposed lake bed. Dust storms have blown up to 75,000 tons of this exposed soil annually, dispersing its salt particles and pesticide residues. This air pollution has caused widespread nutritional and respiratory ailments . Cancers have increased by 30 times; arthritis by 60 times; chronic bronchitis by 30 times. What are the Economic Consequences? Ships lie abandoned on salt-encrusted seabeds, and fishing villages are now up to 50km. from water. Besides, twenty-four species of fish that once thrived there are now extirpated. Crop yields have been diminished by the added salinity, even in some of the same fields irrigated with the diverted water. What comes next? Despite international agencies' new clinics, studies, and infrastructure solutions, and the Central Asian republics' commitment to stabilized water use, the Aral continues shrinking; unless irrigation is cut by one fifthan unlikely scenario, given the region's poverty and dependence on farming, it will continue to shrink. Most recently Kazakhstan built a dam separating the northern and southern portions. This should restore the northern water levels (fed by the Syr Darya), and condemn the southern portion (water from the Amu Darya no longer reaches the Aral Sea). Bibliography • http://edcwww.cr.usgs.gov/earthshots/slow/Aral/A ral • A SEA CHANGE , Harper's Magazine, 0017789X, Oct2000, Vol. 301, Issue 1805 • Google Earth. • unimaps.com/aral-sea/