Impacts of Global Climate Change and Local Water Management On Regional Water Balance and Land-Atmosphere Feedbacks

Land-atmosphere energy and moisture fluxes are an important component of regional climate. Recent studies have shown that anthropogenic climate change is altering the hydrologic cycle at global and regional scales, including precipitation amount, frequency, and intensity, evaporative demand, and net radiation at the surface. Other studies suggest that local water management practices, including groundwater pumping and irrigation, alter soil moisture and groundwater depth alter the surface water-energy balance and may feed back on local climate. Here we use ParFlow, a three-dimensional, variably-saturated groundwater flow model with integrated land-surface and overland flow processes, to examine the influences of climate change and water management on land surface energy and water fluxes over the Southern Great Plains region of North America. Local and basin-scale water and energy budgets are compared between multiple climate and water management scenarios, focusing on groundwater recharge and storage, streamflow, and root zone soil moisture. Results demonstrate that in addition to the impacts of anthropogenic climate change on regional hydrology, anthropogenic changes in regional hydrology have the potential to significantly alter local and regional climate.