The small Aral is falling again: twenty years after the Kok-Aral dam, satellite level, lake area and Syr darya inflow, 1993-2026

Abstract

In 2005 the Kok-Aral dam separated the northern part of the Aral Sea, the Small Aral, from the drying southern part. This study uses satellite altimetry from 1992 to 2026, Landsat measurements of the lake's area in 2016-2024 and the winter inflow of the Syr Darya recorded by the Interstate Commission for Water Coordination to ask whether the gain from the dam has lasted. The summer level of the Small Aral rose by 1.52 m in the first year after the dam, from 40.64 m in 2005 to 42.16 m in 2006, and stayed at about 42.48 m on average until 2020. After 2020 it fell to 41.64 m on average in 2021-2025, and the lake's area fell by about 7%. The fall is not an artefact of a change of satellite: at each of the four changes of satellite the old and new instruments agree within a few centimetres. It coincides with less water reaching the lake: the winter inflow at the Karateren gauge fell from 3.32 km3 on average in the winters of 2015/16-2017/18 to 1.35 km3 in 2018/19-2024/25, and the lake's area follows the sum of the last two or three winters (r = 0.81 and 0.91) more closely than the last winter alone, although with only seven or eight years these figures are uncertain. The results do not support the author's view that the dam brought little change, but show that its gain is not permanent.

Keywords: Aral Sea, Small Aral, Kok-Aral dam, satellite altimetry, Landsat, Syr Darya, water balance

Список литературы

1. Micklin P. The future Aral Sea: hope and despair // Environmental Earth Sciences. 2016. Vol. 75, No. 9. Art. 844. https://doi.org/10.1007/s12665-016-5614-5
2. Singh A., Seitz F., Schwatke C. Inter-annual water storage changes in the Aral Sea from multi-mission satellite altimetry, optical remote sensing, and GRACE satellite gravimetry // Remote Sensing of Environment. 2012. Vol. 123. P. 187-195. https://doi.org/10.1016/j.rse.2012.01.001
3. Liu Q., Lee Y.-K., Grassotti C., Liang X., Kidder S.Q., Kusselson S. The challenge of surface type changes over the Aral Sea for satellite remote sensing of precipitation // IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing. 2022. Vol. 15. P. 8650-8655. https://doi.org/10.1109/JSTARS.2022.3212647
4. NASA Goddard Space Flight Center, USDA Foreign Agricultural Service. G-REALM: Global Reservoir and Lake Monitor, 10-day lake product, target 001442 (Aral Sea 3). https://blueice.gsfc.nasa.gov/gwm/lake/Index (accessed 24.09.2026).
5. U.S. Geological Survey. Landsat Collection 2 Level-2 Science Products, via Microsoft Planetary Computer. https://planetarycomputer.microsoft.com/dataset/landsat-c2-l2 (accessed 03.10.2026).
6. Interstate Commission for Water Coordination of Central Asia (ICWC). Information bulletins No. 70, 73, 77, 81, 84, 87, 91, 96, 100, 108: channel balance of the Syr Darya for the non-growing season. http://www.cawater-info.net/library/rus/icwc/ (accessed 21.10.2026).
7. Здесь была река. Почему обмеление Сырдарьи достигло критической отметки // Tengrinews.kz. 02.11.2021. https://tengrinews.kz/article/zdes-reka-pochemu-obmelenie-syirdari-dostiglo-kriticheskoy-1663/ (accessed 30.10.2026).

Как цитировать

Nazarbayev Intellectual School, Taraz, Kazakhstan The small Aral is falling again: twenty years after the Kok-Aral dam, satellite level, lake area and Syr darya inflow, 1993-2026 // Central Asian Scientific Journal. – 2026. – No. 4(32), Vol. 2. – Pp. 215–218. – DOI: 10.5281/zenodo.23890176.