Climate Change Mitigation Could Exacerbate U.S. Water Deficits


Ongoing integrated modeling efforts focus on devising sustainable climate change mitigation policies and jointly considering potential synergies and constraints within the climate-energy-water nexus. While there is evidence that climate warming will contribute to increasing intensity and duration of drought, understanding the overall impact of climate change mitigation on water resources requires accounting for the impact of mitigation-induced changes in water demands from human activities. In a study led by Department of Energy (DOE) scientists at Pacific Northwest National Laboratory (PNNL), researchers used a regional integrated assessment model and a regional Earth system model at high spatial and temporal resolutions over the United States to compare the implications of two representative concentration pathways under consistent socioeconomic conditions. By using integrated, high-resolution models of human and natural system processes, the scientists show that in the United States, over the course of the 21st century and under one set of consistent socioeconomics, reductions in water stress from slower rates of climate change resulting from emission mitigation are overwhelmed by the increased water stress from the emission mitigation itself. The finding that the human dimension outpaces the benefits from mitigating climate change is contradictory to the general perception that climate change mitigation improves water conditions. This research shows the potential for unintended and negative consequences of climate change mitigation.


Work was supported by PRIMA, a Laboratory Directed Research and Development program at Pacific Northwest National Laboratory. This research also leveraged capabilities funded by DOE’s Integrated Assessment Research and Earth System Modeling programs.


Hejazi, M. I., N. Voisin, L. Liu, L. M. Bramer, D. C. Fortin, J. E. Hathaway, M. Huang, P. Kyle, L. R. Leung, H.-Y. Li, Y. Liu, P. L. Patel, T. C. Pulsipher, J. S. Rice, T. K. Tesfa, C. R. Vernon, and Y. Zhou. 2015. “21st Century United States Emissions Mitigation Could Increase Water Stress more than the Climate Change It is Mitigating,” Proceedings of the National Academy of Sciences (USA), DOI: 10.1073/pnas.1421675112.