The Inner Tibetan Plateau (TP) is an endorheic basin with densely distributed lakes that serve as "sentinels" of climate change. With climate warming and humidification, the lakes on the Inner TP have experienced a dramatic expansion; drainage reorganization events can occur, which in turn, pose a flood risk to surrounding villages and roads or break existing watersheds, converging into exorheic basins and threatening the ecological environment. Therefore, an effective and accurate estimation of lake water storage (LWS) changes on the Inner TP under climate change is urgently needed.

 

Recently, a collaborative research team led by the Institute of Atmospheric Physics at the Chinese Academy of Sciences estimated the LWS for 18 lakes (>300 km²) on the Inner TP from 2002 to 2018 using Gravity Recovery and Climate Experiment (GRACE) data and land surface model simulations.

 

Lhanag-tso lake, with the high altitude of 4574 meters (Image by WANG Longhuan)

 

"The estimated LWS agreed well with the multi-source satellite altimetry data. The LWS of the 18 lakes on the Inner TP expanded rapidly with an increasing rate of 26.92 mm every year," said Prof. JIA Binghao, "the increasing rate of LWS by the mid-twenty-first century for an intermediate scenario is predicted to decrease to 40% of that in recent decades based on an artificial neural network model."

 

This prediction is supported by the terrestrial water storage and glacial runoff projections on the Inner TP. The results of this study highlight the importance of water resource mitigation and adaptation to avoid flood threats from increased LWS on the Inner TP.

 

"The LWS estimations based on GRACE data and land surface model can be used to identify regional changes in lakes for areas with limited available data, which is a helpful tool for monitoring lake water resource changes," said Prof. XIE Zhenghui.

 

This work has been published in Science Bulletin. 

 

Reference:

Binghao Jia, Longhuan Wang, Zhenghui Xie, 2023: Increasing lake water storage on the Inner Tibetan Plateau under climate change. Science Bulletin, 68(5), 489-493. https://doi.org/10.1016/j.scib.2023.02.018.