The ‘Asian water tower’ is brimming — with glacial melt water
The Tibetan Plateau’s store of underground water has increased, but the replenishment is coming mainly from melting glaciers, snow and permafrost1.
The plateau, known as the ‘Asian water tower’, spans 3 million square kilometres across south and central Asia, and its rivers provide water to more than 2 billion people. Understanding how climate change affects the plateau’s groundwater — the water stored in subsurface pores, fissures and caves — is crucial for maintaining water security and food production.
Yiguang Zou at the Southern University of Science and Technology in Shenzhen, China, and colleagues combined data from satellite observations, models and other sources to assess changes in the plateau’s total water storage and in reserves such as lakes, glaciers, snow and permafrost. By subtracting those reserves from the total, the researchers found that the Tibetan Plateau’s groundwater cache rose by about 5.5 billion tonnes per year from 2003 to 2016.
Precipitation declined during that time, and water stored in solid forms — as ice and snow — shrank by nearly 18 billion tonnes per year, indicating that climate change-induced melting had led to the increase in groundwater.
doi: https://doi.org/10.1038/d41586-022-02989-x
References
Zou, Y. et al. Geophys. Res. Lett. https://doi.org/10.1029/2022GL100092 (2022).
