To sustain growing food demand and increasing standard of living, global water withdrawal and consump-tive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over large scales, a number of macro-scale hydrological models (MHMs) have been developed in recent decades. However, few models consider the interaction between terrestrial wa-ter fluxes, and human activities and associated water use, and even fewer models distinguish water use from surface water and groundwater resources. Here, we couple a global water demand model with a global hydrological model and dynamically simulate daily water withdrawal and consump-tive water use over the period 1979–2010, using two re-analysis products: ERA-Interim and MERRA. We explic-itly take into account the mutual feedback between supply and demand, and implement a newly developed water allo-cation scheme to distinguish surface water and groundwater use. Moreover, we include a new irrigation scheme, which works dynamically with a daily surface and soil water bal-ance, and incorporate the newly available extensive Global Reservoir and Dams data set (GRanD). Simulated surface water and groundwater withdrawals generally show good agreement with reported national and subnational statistics. The results show a consistent increase in both surface water and groundwater use worldwide, with a more rapid increase in groundwater use since the 1990s. Human impacts on ter-restrial water storage (TWS) signals are evident, altering the seasonal and interannual variability. This alteration is partic-ularly large over heavily regulated basins such as the Col-orado and the Columbia, and over the major irrigated basins such as the Mississippi, the Indus, and the Ganges. Including human water use and associated reservoir operations gener-ally improves the correlation of simulated TWS anomalies with those of the GRACE observations.
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