Vulnerability of soil moisture and ground water stocks to meteorological droughts from anthropogenic influences

A meteorological drought often originates as an atmospheric water deficit, interacts with the terrestrial components over land surface, and propagates deficits along the hydrologic cycle. As this propagation phenomenon occurs through the medium of the land surface, human induced land surface management plays a crucial intermediary role in translating the effects of meteorological drought to hydrologic component variations. Therefore, in this study, we quantify the effect of human land surface management practices in propagating the meteorological deficits through soil moisture and ground water; two crucial components of the hydrologic cycle. This is quantified by contrasting model simulations that employ the assimilation of global remote sensing information with those that do not incorporate observational constraints. Specifically, the study employs a global modeling setup that assimilates soil moisture, terrestrial water storage, and leaf area index estimates from remote sensing over the past two decades. The difference in the spatio-temporal responses of soil moisture and ground water variability to meteorological droughts in global simulations with and without data assimilation is used to quantify information about human interference hotspots on drought propagation. This framework can be further utilized attribute the effect of human interference on several hydrologic components.