The disappearance of the Aral Sea, 1960–2026

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In 1960 the Aral Sea, on the border of Kazakhstan and Uzbekistan, was the fourth-largest lake in the world: about 67,600 km² of brackish water with a fishing fleet, canneries and more than a thousand islands. From the early 1960s Soviet irrigation schemes took the water of its two rivers, the Amu Darya and the Syr Darya, to grow cotton and rice in the desert. The sea fell, from the mid-1970s by more than half a metre a year, split into a northern and a southern lake around 1989, and its southern part broke up further. Since 2005 the Kokaral dike has held the North Aral at about 42 m and its fish have come back; the South Aral is a narrow, very salty western basin and a shallow eastern basin that is now dry in most years. In September 2026, the last frame, about 4,900 km² of open water was left, 7% of the 1960 sea. The pale shape is the sea of 1960, now mostly dry seabed; islands are drawn in the same colour. The blue is the water in each year, at the late-summer low (every frame is dated 1 September). 1960–1984 are reconstructions: each shore is the contour of the Copernicus 90 m elevation model, measured in 2011–2015 when the old seabed was dry, at the sea level published for that year (53.4 m in 1960, 42.75 m in 1984, Baltic datum). 1986–2021 come from Landsat: water that was present all year in the JRC Global Surface Water yearly classification (v1.4); cells without images take their state from the neighbouring years, and 1985, 1988, 1995 and 1997 are left out because too few images exist. For 1986 and 1987 so few images exist that their shapes lean on 1989: the fall of 5,700 km² between 1984 and 1986 is too steep and the near-standstill until 1989 too flat, while the measured level fell steadily through those years. 2022–2026 come from Sentinel-2 images of August and September: water where the MNDWI index is above 0.3, a threshold that reproduces the JRC result for 2021. Lakes under about 40 km² and the lakes and reservoirs of the Amu Darya delta, which canals keep full, are left out, and shores are smoothed to about 250 m. The Berg Strait between the northern and the southern lake was by 1986 a channel too narrow for this method; it is drawn about 0.8 km wide in 1986 and 1987, until the split. Areas in the captions are measured on these shapes, and the percentage is the share of the 1960 area; published figures differ by a few per cent in most years, and by much more in years when the shallow eastern basin holds a thin sheet of water (2018: 8,900 km² here, 6,990 km² in the CAWater-Info tables). The satellite basemap shows today's land. Sources: JRC Global Surface Water, Pekel et al. 2016 (Nature 540), © European Union, CC BY 4.0; Copernicus DEM GLO-90 (ESA; © DLR e.V. 2010–2014 and © Airbus Defence and Space GmbH 2014–2018, provided under COPERNICUS by the European Union and ESA); Copernicus Sentinel-2 data 2022–2026; CAWater-Info / SIC ICWC morphometric tables; Micklin 1988 (Science 241); Micklin, Aladin, Plotnikov & Ermakhanov 2016; Aladin et al., Northern Aral Sea (ILEC); Ermakhanov et al. 2012; Izhitskiy et al. 2016; World Bank SYNAS-1 completion report (2011); NASA Earth Observatory.

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