Climate Change and Terrestrial Water Storage Decline over the Euphrates River Basin

Abstract:

The Euphrates river basin is a dryland basin indicated by the aridity index (the ratio of annual precipitation to potential evapotranspiration). The basin has been experiencing water shortages, being exacerbated by high demands for evaporative water in a warming climate and impacts from human interventions. As a transboundary river basin, limited water resources over the Euphrates may cause international tension and conflicts. Previous research has found a decadal drying trend over the basin using the terrestrial water storage (TWS) anomaly data derived from the Gravity Recovery and Climate Experiment (GRACE) twin satellites. However, current macroscale hydrological models tend to underestimate the drying trend, impeding the understanding of potential mechanisms driving the “dryland-drying” condition. Here, we use the Noah-MP land surface model to investigate impacts of climatic variations on the negative TWS trend. We focus our research project on explaining 1) how climate variations influence the demand-and-supply contrast of the atmospheric water, and 2) how land surface processes such as vegetation, soil moisture, and groundwater dynamics regulate water fluxes between the atmosphere and land surface, and ultimately TWS variations under a changing climate. Our research will provide useful insights into understanding ecohydrology and water managements over dryland regions.