Implementing sectoral water usage in the Community Earth System Model for projecting future water resource availability

Due to the combined effect of human-driven depletion and anthropogenic climate change, groundwater storage is decreasing across the globe. This trend will potentially have an adverse impact on future human socio-economic development, by increasing the frequency and duration of both hydrological and socio-economic droughts as well as generating inter-sectoral competition for limited water resources.

Large-scale modelling studies on changes in groundwater availability can be separated into two big families. First, hydrological impact models actively consider water usage across sectors but ignore land-atmosphere interactions by design. Second, Earth System Models consider two-way interactions between climate and groundwater resources, but almost never consider the anthropogenic water resource depletion, except in some cases for irrigation.

The goal of this study is to connect the expertise of these two families by implementing domestic and industrial water usage in the Community Earth System Model version 2. Using land-atmosphere coupled simulations, we will revisit previously computed trends in future groundwater availability by simultaneously accounting for climate change and anthropogenic water resource usage.