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The tributary rivers Amu Darya and Syr Darya contribute major amounts of water to the hydrological budget of the endorheic Aral Sea.Processes controlling the flow of water into rivers in the headwater systems in Tien Shan (Kyrgyzstan) and Pamir (Tajikistan) are therefore most relevant.Lake water mineralization is strongly dependent on river discharge and has been inferred from spectrometrically determined gypsum contents.Comparison of highresolution mineralization data with other proxies for tracing precipitation in NW China indicate that mineralization over the past ~2000 years in the Aral Sea reflects snow cover variability and glacier extent in Tien Shan and Pamir (at the NW and W edges of the Tibetan Plateau).Snow cover in W Central Asia is preferentially a winter expression controlled by temperature patterns that impact the moisture-loading capacity over N Europe and NW Asia.We observed that the runoff, resulting from warmer winter temperatures in W Central Asia and resulting in a reduction of snow cover, decreased between AD 100~300, AD 1150~1250, AD 1380~1450, AD 1580~1680 and during several low frequency events after AD 1800.