The South Aral Sea was a lake in the basin of the former

Aral Sea The Aral Sea ( ; kk, Арал теңізі, Aral teñızı; uz, Орол денгизи, Orol dengizi; kaa, Арал теңизи, Aral teńizi; russian: Аральское море, Aral'skoye more) was an endorheic lake lying between Kazak ...

which formed in 1987 when that body divided in two, due to diversion of river inflow for

agriculture Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people ...

. In 2003, the South Aral Sea itself split into eastern and western basins, the ''Eastern Sea'' and the ''West Aral Sea'', connected by a narrow channel (channel bed at an elevation of ) that balanced surface levels but did not allow mixing, and in 2005 the North Aral Sea was dammed to prevent the collapse of its fisheries, cutting off the only remaining inflow to the southern lakes. In 2008, the Eastern Sea split again, and in May 2009 had almost completely dried out, leaving only the small permanent Barsakelmes Lake between the Northern and Western Seas and increasing the expanse of the Aralkum desert. In 2010, it was partially filled again by meltwater, and by 2014 was once again dry. The West Aral Sea has some replenishment from groundwater in the northwest, and so is likely to avoid desiccation.

Background

The

began shrinking in the 1960s, when the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

decided that the two rivers feeding it, the

Amu Darya The Amu Darya, tk, Amyderýa/ uz, Amudaryo// tg, Амударё, Amudaryo ps, , tr, Ceyhun / Amu Derya grc, Ὦξος, Ôxos (also called the Amu, Amo River and historically known by its Latin name or Greek ) is a major river in Central Asi ...

and the

Syr Darya The Syr Darya (, ),, , ; rus, Сырдарья́, Syrdarjja, p=sɨrdɐˈrʲja; fa, سيردريا, Sirdaryâ; tg, Сирдарё, Sirdaryo; tr, Seyhun, Siri Derya; ar, سيحون, Seyḥūn; uz, Sirdaryo, script-Latn/. historically known ...

, would be diverted in order to

irrigate Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow crops, landscape plants, and lawns. Irrigation has been a key aspect of agriculture for over 5,000 years and has been develo ...

cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...

and food crops in

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...

and

Uzbekistan Uzbekistan (, ; uz, Ozbekiston, italic=yes / , ; russian: Узбекистан), officially the Republic of Uzbekistan ( uz, Ozbekiston Respublikasi, italic=yes / ; russian: Республика Узбекистан), is a doubly landlocked co ...

. In 1987, due to an accelerated loss of water, the Aral Sea was split into northern and southern parts; the northern part is the current North Aral Sea.

Salinity

In 2007, the western basin had a

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

of 70 g/L and the eastern basin 100 g/L. Once the water level falls below the connecting channel (elevation 29 m), the salinities can be expected to diverge further. Under current conditions, the eastern basin may receive water from the

in wet years, fluctuating in salinity and flooding an area of up to 4500 km² in salt water to a depth of about one meter, which would preclude any economic activity in the area, while the western basin becomes increasingly saline. Water diversion from the Amu Darya directly to the deeper western basin could lower its salinity enough to allow resumption of local fisheries, while allowing the eastern basin to desiccate almost entirely and avoiding the problems of flooding.

Current situation

The West Aral Sea is expected to stabilize at , a mean depth of , and a maximum depth of , assuming groundwater discharge at the rate of per year.Peter O. Zavialov, 2005, ''Physical oceanography of the dying Aral Sea,'' p 112 The Eastern Sea dried up completely in the summer of 2009, apart from the small permanent Barsakelmes Lake (between the Northern and Western seas), but it received some water from snow melt in the spring of 2010. It is expected to alternate between complete desiccation in the summers and the occasional flood from the Amu Darya or spillover from the dam holding back the North Aral Sea, though a second dike, begun in 2010, may reduce the incidence of the latter. In 2015, the Western Sea was starting to split into two, as the channel that connects the central part of the sea and the small North-Eastern part was growing skinnier. (This can be seen on the 2014 picture.) Since 2018, the split has been complete.https://eurasianet.org/northern-arals-promise-stunted-by-dam-height-international-disputes Satellite image of 2020

References

{{Lakes of Kazakhstan Aral Sea Lakes of Kazakhstan Lakes of Uzbekistan