GRACE-based terrestrial water storage anomaly estimation and its application in hydrological science

Abstract

Terrestrial water storage (TWS) is an important water cycle component for ecosystems, hydroclimate, and human activities. Traditionally, basin-scale TWS has been treated as residual for precipitation, runoff, and evapotranspiration. In recent years, TWS anomaly has been estimated via satellite remote sensing, although it is limited to large river basins. The amount of TWS covers all land water and ice such as soil moisture, snow cover, surface water, and ice in permafrost. In this article, we will explain the method of estimating TWS anomaly (TWSA) through satellite gravity observation GRACE (Gravity Recovery and Climate Experiment) and introduce its application mainly to the Siberian large river basin. The estimation of TWSA fluctuations by GRACE has led to several breakthroughs in watershed hydrology and hydrological studies. Long-term continuation of TWSA observation contributes to further advancements in water cycle research.