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Posts tagged Endorheic Lake

Lake Balqash, Kazakhstan and Lake Issyk Kul, Kyrgyzstan – December 24th, 2008

December 24th, 2008 Category: Image of the day, Lakes

Lake Balqash, Kazakhstan and Lake Issyk Kul, Kyrgyzstan - November 24th, 2008

Lake Balqash, Kazakhstan and Lake Issyk Kul, Kyrgyzstan - November 24th, 2008

In the lower part of the image we can see Lake Issyk Kul, in eastern Kyrgyzstan, navy blue in color and surrounded by the snow-covered Tian Shan mountains.

Although it is surrounded by snow-capped peaks, it never freezes; hence its name, which means “warm lake” in the Kyrgyz language.

It is an endorheic lake (a body of water that does not flow into the sea), the ninth largest lake in the world by volume and the second largest saline lake after the Caspian Sea.

Lake Issyk Kul has a length of 182 km, a width of up to 60 km, and covers an area of 6,336 km². This makes it the second largest mountain lake in the world behind Lake Titicaca in South America.

Located at an altitude of 1,608 m, it reaches 668 m in depth.

In the upper portion of the image, we can see Lake Balqash, in southeastern Kazakhstan. It can be observed more clearly than Lake Issyk Kul as it appears lighter in color.

Lake Balqash is the second largest lake in Central Asia after the Aral Sea. It is a closed basin that is part of the endorheic basin that includes the Caspian and Aral seas.

The lake currently covers 16,996 km² (6,562 sq mi), but, like the Aral Sea, it is shrinking because of the diversion of water from the rivers that feed it.

The lake has a mean depth of 5.8 m, and a maximum of 25.6 m. The western half of the lake is fresh water, while the eastern half is saline. The mean depth of the eastern part is 1.7 times that of the western.

The water pollution of Balkhash is intensified as urbanisation and industrialisation in the area grow rapidly. Extinctions of species in the lake due to its decreasing area, as well as overfishing activities, are cause for alarm among conservationist organisations worldwide.

source Wikipedia

The Shrinking of the Aral Sea – December 18th, 2008

December 18th, 2008 Category: Image of the day, Lakes

The shrinking of the Aral Sea - July 1st, 2006 and December 2nd, 2008

The shrinking of the Aral Sea - July 1st, 2006 and December 2nd, 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.

source Wikipedia