HR: 0800h
AN: H21G-0819    [Abstracts]
TI: Streamflow Reconstructions and Periods of Drought in the Upper Green River Basin, Wyoming, USA
AU: * Barnett, A
EM: barnetta@uwyo.edu
AF: University of Wyoming Departement of Civil Engineering, 1000 East University Avenue Dept 3295, Laramie, WY 82071,
AU: Watson, T
EM: twatson@uwyo.edu
AF: University of Wyoming Departement of Civil Engineering, 1000 East University Avenue Dept 3295, Laramie, WY 82071,
AU: Gray, S T
EM: sgray8@uwyo.edu
AF: Director, Water Resources Data System and Wyoming State Climatologist, 1000 East University Avenue Dept 3295, Laramie, WY 82071,
AU: Tootle, G
AF: University of Wyoming Departement of Civil Engineering, 1000 East University Avenue Dept 3295, Laramie, WY 82071,
AB: The upper Green River 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 drought has greatly stressed the water supply system of the Colorado River. This has resulted in increased interest in the Colorado River Compact and related "Law of the River." The current research developed proxy records (streamflow) derived from tree ring chronologies. These streamflow reconstructions provide an effective way to analyze patterns of drought over a period of time extending beyond any instrumental record in the upper Green River Basin (GRB). Six new tree ring chronologies were developed in the foothills of the Wind River Mountain Range, along the eastern boundary of the upper GRB. The six new chronologies consisted of three Douglas fir (Pseudotsuga menziesii) and three limber pine (Pinus flexilis) sites. The newly developed tree ring chronologies and existing chronologies around the region were used in developing the streamflow reconstructions. Nine streamflow reconstructions were developed for both headwater stations (utilizing unimpaired streamflow records) and stations lower in the basin (utilizing naturalized streamflow records). Traditionally, streamflow reconstructions have been limited to large rivers, but reconstructing headwater stream records provides information to water users high in the basin as well as providing spatial variations in streamflow variability across the river basin. All upper basin reconstructions extended back to the year 1615. The most downstream station in the upper GRB (Green River, near Greendale, UT) was extended to 1439. The coefficient of variance (R2) for this reconstruction is 0.65. Different modes of drought were identified for the Green River, near Greendale, UT reconstruction. Annual extremes (wet and dry) and persistent wet and dry (drought) periods were identified. The wet and dry periods identified were analyzed and compared with long term trends in the reconstructed streamflow record.
DE: 1812 Drought
DE: 1860 Streamflow
DE: 1869 Stochastic hydrology
DE: 1884 Water supply
SC: Hydrology [H]
MN: 2007 Fall Meeting