The Asian Water Tower is Losing 24 Billion Tonnes of Groundwater Annually

Groundwater reserves beneath High Mountain Asia (HMA) are shrinking at an alarming rate, according to a recent satellite-based study led by Prof. Shudong Wang from the Aerospace Information Research Institute of the Chinese Academy of Sciences. The region, which supports farming, cities, and ecosystems across numerous downstream countries, is experiencing a decline of about 24.2 billion tonnes of groundwater annually.

The study utilized an AI-powered assessment model that integrates satellite observations and Earth system modeling to analyze groundwater storage changes over the past two decades. The findings indicate that approximately two-thirds of HMA has experienced declining groundwater storage from 2003 to 2020, with the most significant losses occurring in heavily populated basins such as the Ganges-Brahmaputra, Indus, and Amu Darya.

Climate-related factors account for nearly half of the observed variations in groundwater storage, while human water withdrawals, particularly for irrigation in agricultural regions, have increasingly contributed to depletion since 2010. Researchers project that groundwater losses will persist if current water use patterns remain unchanged. Although increased glacier melt may temporarily mitigate the crisis around the 2060s, this effect is not sustainable and is expected to be followed by accelerated losses, posing a greater threat to agricultural areas reliant on these water reserves.