Water Resources Research Act Program

Details for Project ID 2006WY32B

Predicting Drought in the Green River Basin

Institute: Wyoming
Year Established: 2006 Start Date: 2006-03-01 End Date: 2008-02-28
Total Federal Funds: $13,441 Total Non-Federal Funds: $99,617

Principal Investigators: Glenn Tootle

Project Summary: The Green River Basin (GRB) represents a vital water supply region for southwestern Wyoming and Upper / Lower Colorado River Compact states. Rapid development in the southwestern U.S. (e.g., Las Vegas, Phoenix) combined with the recent 5-year drought has greatly stressed the water supply system of the Colorado River. This has resulted in increased interest in re-evaluating the Compact and related Law of the River. The proposed two-year research project will use proxy records derived from tree rings to examine climatic controls on GRB streamflow and assess how natural interdecadal variability might impact delivery of water from the GRB. The proposed research will initially review existing streamflow proxies for the GRB and assess how reconstruction methodology might affect key elements (e.g. reconstructed drought magnitude) of these records. Next, an investigation of long-term streamflow variability, focusing on extreme events such as mega-droughts, will be performed. This investigation includes evaluating the influence of various atmospheric oceanic influences [e.g., El Niouthern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO)] on GRB streamflow. This analysis will also address how large-scale climatic drivers affect the spatial distribution of droughts, and therefore the demand for Colorado River water, across the Compact states. Finally, the results of the research will be used to develop probabilistic drought forecasts for the GRB. These forecasts would utilize both empirical probabilities for drought risk derived from the tree-ring record and links between streamflow and climatic drivers like ENSO and the PDO.