Climate change will impact water supplies, exacerbating existing pressures on water resources caused by population and economic growth. Given the combination of these stressors, the sustainability of water resources in future decades is a concern
in many parts of the world. This study presents an integration of water withdrawal projections and future estimates of renewable water supply across the United States to assess future water availability in the face of a changing climate. The water demand projections in this work are based on business-asusual
trends in growth, particularly of population and energy demand, and renewable water supply projections are based on the average results of an ensemble of sixteen established climate models.
The analysis is performed using annual water use data at the U.S. county level, and using global climate model outputs for temperature and precipitation, both projected 20-40 years into the future. The analysis provides a national-scale evaluation of
the results of changing water demand and supply, and helps identify regions that are most susceptible to climate change.