The Colorado River is the dominant water source for the southwestern United States, crossing through seven states before reaching Mexico. The river supplies water to approximately 36 million people, irrigates nearly six million acres of farmland within and beyond the basin, and contributes an estimated 26 billion dollars each year to the region’s recreational economy. Yet the Colorado River’s water supply is already fully allocated, meaning that the economic and environmental health of the region is closely tied to the river’s streamflow.
Climate projections for the Southwest show a future marked by chronic drought and substantial reductions in streamflow. The region has already been impacted by climate change, experiencing warmer temperatures and more intense drought, particularly in late spring and early summer, resulting in reduced streamflow. In order to appropriately manage the Colorado River under changing conditions, water resource planners require reliable projections of future streamflow.
This project seeks to characterize how changing climate conditions affect cool and warm season precipitation in the Colorado River basin and the corresponding impacts on streamflow. Specifically, researchers will examine whether human-caused climate change interacts with natural variations in climate (such as the El Niño-Southern Oscillation) intensify climate extremes, such as severe drought. Researchers will implement a new technique to downscale global climate model data, to produce more accurate streamflow projections that can be used to make local- and regional-scale water management decisions. The results of this project will provide water managers and decision-makers with valuable insight into how the Colorado River’s water supply might change in the future, facilitating long-term planning of the river’s resources.