Adaptation Planning for Climate Change Impacts on Irrigated Agriculture in California

TitleAdaptation Planning for Climate Change Impacts on Irrigated Agriculture in California
Publication TypeConference Paper
Year of Publication2012
AuthorsWinter, Jonathan M., Fekete B M., Ruane Alex C., and Rosenzweig Cynthia
Conference NameAmerican Geophysical Union
Keywordsclimate impacts, drought, global environmental change, Hydrology, impacts of global change, irrigation

Climate change presents a unique challenge to water resources managers. As evolving patterns of precipitation alter the quantity and quality of runoff within watersheds, demand from competing sectors continues to increase. The agricultural industry is especially sensitive to future shifts in water supply and demand since irrigated croplands require large quantities of water at low prices. California is of interest because of its $35-billion agricultural sector, limited water resources, and complexity. This presentation explores future changes to the water resources of the western United States and the implications of these changes on California’s irrigated agriculture. North American Regional Climate Change Assessment Program (NARCCAP) model output was used to drive current (1980-1999) and future (2050-2069) Water Balance/Transport Model (WBM) simulations of key water cycle components, including evapotranspiration, soil moisture, surface runoff, and groundwater recharge, as well as some water use components, including agricultural and electrical, over the contiguous United States. Climatic and hydrologic data were then synthesized to evaluate whether drought conditions in California, both historic and future, dominantly coincide with droughts in adjacent states and identify neighboring regions with the potential to provide supplemental water resources to California. Uncertainty in the assessment of future water supply was analyzed using multiple general circulation model-regional climate model pairs from NARCCAP.