Future water resource shifts in the high desert Southwest of Northern New Mexico, USA

Abstract Study Region This study focuses on the headwaters of the Upper Rio Grande basin, the Pajarito Plateau, northern New Mexico, USA. Study Focus Our work examines 2050s water balance changes using the INFIL hydrologic model run under different downscaled earth system model (ESM) projections to simulate impacts on runoff, infiltration, and overall water regime shifts. New Hydrological Insights for the Region Climate change is shifting the water balance in the high desert of the US Southwest. Across the Pajarito Plateau, increases in temperature and changing precipitation form and delivery result in increased rain during winter, spring and fall, and decreased snow during winter (47 % less snow is projected to fall). ESM projections of summer rainfall vary, with increases and decreases possible. High elevation recharge zones exhibit increased runoff and infiltration, but across the region aridity also increases due to warmer temperatures. This dichotomy illustrates the complexities in regional responses that occur across time and space, and require a firm understanding to mitigate impacts on the region’s ability to sustainably manage water resources within the next 30 years.