Water Resources Grant: Projecting Colorado River Streamflow Under Climate Change

The project will address the projection of future water resources in the Colorado River basin with a physically-based modeling approach. The project incorporates dynamical downscaling and hydrologic modeling components. With dynamical downscaling, a regional atmospheric model will be forced with data from a courser resolution global model (grid spacing of hundreds of kilometers) to create climate information at a more regionalized scale (grid spacing of single to tens of kilometers). Hydrologic modeling will be performed using the Variable Infiltration Capacity (VlC) model (Liang et al., 1994) and will include the representation of subgrid scale variability in vegetation coverage, topography, precipitation, and soil moisture storage capacity. Regional climate modeling will add substantial value in the climatological representation of both cool and warm season precipitation in the Southwest (e.g. Dominguez et al. 2012; Castro et al. 2012).

The results from the regional climate projections produced by this project will provide a long-term (100 years and longer) continuous modeling product for both United States and Mexico. These regional scale climate projections will produce information at a more relevant spatial scale for decision making. They are also more applicable for use in applications of other disciplines, such as hydrology and ecology, which are in need of finer resolution long-term climate models. Hydrology streamflow projections for the selected river sub-basins will provide valuable guidance for in water resource planning for both Colorado basins.