Understanding the Effects of Seasonal Precipitation Changes on Hydrology and Ecosystems in the Colorado River Basin

The Colorado River provides water to 40 million people in the southwestern United States. Consistent water level declines in Colorado River Basin reservoirs have focused research attention on the long-term changes in winter precipitation and the timing of snowmelt and runoff. Research on how warming temperatures affect winter precipitation and spring snowmelt is ongoing, however, less attention has been given to changes in spring and summer precipitation which also affects water supply, plant growth, and competition between native and non-native plants, and, in turn affects wildfire dynamics and wildlife habitat.  

The amount and timing of summer precipitation is largely influenced by variation in the North American Monsoon. To address knowledge gaps relating to changes in spring and summer precipitation in the Colorado River Basin, this project will analyze historical and future projections of temperature and precipitation, including contributions from the North American Monsoon; assess the consequences of precipitation changes on vegetation, including changes to native and non-native plants; and design research and share results with management partners. The project ultimately aims to improve operational decision-making and inform management of water and other natural resources in the region as climate continues to change.