The changing Aral Sea
The Aral Sea was an endorheic lake lying between Kazakhstan (Aktobe and Kyzylorda Regions) in the north and Uzbekistan (Karakalpakstan autonomous region) in the south. The name roughly translates as "Sea of Islands", referring to over 1,100 islands that once dotted its waters; in the Turkic languages aral means "island, archipelago". The Aral Sea drainage basin encompasses Uzbekistan and parts of Tajikistan, Turkmenistan, Kyrgyzstan, Kazakhstan, Afghanistan and Pakistan. Formerly one of the four largest lakes in the world with an area of 68,000 km2, the Aral Sea has been steadily shrinking since the 1960s after the rivers that fed it were diverted by Soviet irrigation projects. By 2007, it had declined to 10% of its original size, splitting into four lakes - the North Aral Sea, the eastern and western basins of the once far larger South Aral Sea, and one smaller lake between the North and South Aral Seas. By 2009, the southeastern lake had disappeared and the southwestern lake had retreated to a thin strip at the western edge of the former southern sea; in subsequent years, occasional water flows have led to the southeastern lake sometimes being replenished to a small degree. Satellite images taken by NASA in August 2014 revealed that for the first time in modern history the eastern basin of the Aral Sea had completely dried up. The eastern basin is now called the Aralkum Desert. In an ongoing effort in Kazakhstan to save and replenish the North Aral Sea, a dam project was completed in 2005; in 2008, the water level in this lake had risen by 12 m (39 ft) compared to 2003. Salinity has dropped, and fish are again found in sufficient numbers for some fishing to be viable. The maximum depth of the North Aral Sea is 42 m (as of 2008). The shrinking of the Aral Sea has been called "one of the planet's worst environmental disasters". The region's once-prosperous fishing industry has been essentially destroyed, bringing unemployment and economic hardship. The Aral Sea region is also heavily polluted, with consequential serious public health problems More information is available on Wikipedia
We continue our tour around the world in 2017 and today we stop over the Aral Sea. It is a salt lake or inland sea in Central Asia, near the Caspian Sea. The shrinking of the Aral Sea is perhaps the greatest human-made environmental catastrophe ever recorded. The salinity of the lake's waters has increased approximately threefold, adversely affecting plant and animal life here. The fishing industry has declined precipitously, and the waters are no longer transparent or filled with sturgeon, carp, and herring. The shores are barren and uninhabited, although several villages and large towns, such as Aralsk and Muynak, were located on its shore before 1960, and are now several miles from the water. In these images acquired from the Landsat 7/8 satellites, we aim to show in this time window of 16 years (before - after), the disappearance of what was once one of the main pools of water in the world. Until a few decades ago, the Aral Sea (salt lake of oceanic origin), was the fourth largest lake (sea) in the planet's surface. Today, the Aral Sea has reduced its surface area by 75%, and in only a little more than 10% of water is visible through satellites, while the remaining 90% is all sand. This image comparison demonstrates the benefits of satellite imagery, it that we can monitor the reduction of the Aral Sea over a period of time. Another aim of these images is to promote the opportunity to download Landsat data through the ESA portals, where images captured every day are made available in near real time to the users and the scientific community. Landsat full resolution data products are freely available for immediate download at:  View Landsat 7 ETM high resolution image (JPG 2.9 MB) View Landsat 8 OLI high resolution image (JPG 2.9 MB)
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