The Shrinking of the Aral Sea – December 18th, 2008
The Aral Sea is a landlocked endorheic basin in Central Asia; it lies between Kazakhstan in the north and Karakalpakstan, an autonomous region of Uzbekistan, in the south.
The name roughly translates as “Sea of Islands”, referring to more than 1,500 islands of one hectare or more that once dotted its waters. There are now three lakes in the Aral Basin: the North Aral Sea and the eastern and western basins of the South Aral Sea.
Once the world’s fourth-largest inland sea with an area of 68,000 km², the Aral Sea has been steadily shrinking since the 1960s, after the rivers Amu Darya and Syr Darya that fed it were diverted by Soviet Union irrigation projects.
By 2004, the sea had shrunk to 25% of its original surface area, and a nearly fivefold increase in salinity had killed most of its natural flora and fauna.
By 2007 it had declined to 10% of its original size, splitting into three separate lakes, two of which are too salty to support fish. The once prosperous fishing industry has been virtually destroyed, causing unemployment and economic hardship.
The two side-by-side images here demonstrate how the Aral Sea has changed in the last few years. To the left is an image taken on July 1st, 2006; to the right, an image from December 2nd, 2008. It is easy to see how much the central lake has reduced in size. On the left, it still has some algae growth, with sediments towards the southern shore, and a dark blue area of deeper waters towards the north shore. In the more recent picture, the bright green algal bloom does not appear; rather, the water seems light blue, shallow, and full of sediments.
The Aral Sea is also heavily polluted, largely as the result of weapons testing, industrial projects, pesticides and fertilizer runoff. Wind-blown salt from the dried seabed damages crops, and polluted drinking water and salt- and dust-laden air cause serious public health problems.
The retreat of the sea has reportedly also caused local climate change, with summers becoming hotter and drier, and winters colder and longer.