3rd October 2014 Eastern basin of the Aral Sea has completely dried up This year marks another milestone for the Aral Sea — a once huge lake in Central Asia that has been shrinking rapidly since the 1960s. For the first time in modern history, its eastern basin has completely dried up.
These images, taken by NASA's flagship Terra satellite, show how the Aral Sea has changed in just 14 years. It is now apparent that its eastern basin has completely dried up. The transformation is especially stark when compared to the approximate shoreline location in 1960 (black outline). "This is the first time the eastern basin has completely dried in modern times," says Philip Micklin, a geographer from Western Michigan University and expert on the Aral Sea. "And it is likely the first time it has completely dried in 600 years, since Medieval desiccation associated with diversion of Amu Darya to the Caspian Sea." In the 1950s and 60s, the government of the former Soviet Union diverted the Amu Darya and the Syr Darya – the region's two major rivers – in order to irrigate farmland. This diversion began the lake's gradual retreat. By the year 2000, the lake had separated into the North (Small) Aral Sea in Kazakhstan and the South (Large) Aral Sea in Uzbekistan. The South Aral had further split into western and eastern lobes.
The eastern lobe of the South Aral nearly dried in 2009, then saw a huge rebound in 2010. Water levels continued to fluctuate annually in alternately dry and wet years. According to Micklin, the desiccation in 2014 occurred because there has been less rain and snow in the watershed that starts in the Pamir Mountains; this has greatly reduced water flow on the Amu Darya. In addition, huge amounts of river water continue to be withdrawn for irrigation. The Kok-Aral Dam across the Berg Strait – a channel that connects the northern Aral Sea with the southern part – played some role, but has not been a major factor this year, he said. Formerly the world's fourth largest lake (pictured below in 1964), the Aral Sea is often described as the worst ecological disaster on the planet. With its eastern half now gone, what remains of the western half is expected to vanish by 2019.
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