New data sets to estimate terrestrial water storage change

The total amount of water stored in a river basin affects streamflow at various timescales and defines the river basin's response to atmospheric forcing. For example, spring runoff in mountainous midlatitude catchments depends on winter snowpack, and groundwater storage sustains flow during dry periods. An accurate estimation of terrestrial water storage (TWS) is thus paramount for improved water management. Direct determination of TWS is difficult due to insufficient in situ data on space-time variability of hydrologic stores (snow, soil moisture, groundwater) and fluxes (precipitation, evapotranspiration). However, alternative methods using new data sets show great potential to improve the estimation of intra-annual and interannual TWS dynamics.