Correlations Between Climate and Streamflow in the Little Washita River Watershed, OK

Three substantially different methods have been used to relate the runoff in the Little Washita River, OK, to climate parameters. One method uses a detailed watershed runoff model SWAT, which integrates several well established hydrologic runoff model components. The second approach is based on a mean monthly water budget and calculates runoff as one of its components. The third approach simply correlates measured runoff with measured weather parameters. The timescales of these tlrree methods are substantially different: daily, monthly, and seasonal (3-months) for the three methods, respectively. The timescale is the shortest for the most process oriented model and the longest for the purely statistical method. The simplest of these three methods in terms of data requirement and computational effort is described herein and applied to the Little Washita Watershed. The other two are explained in reports by Mohseni and Stefan (1996) and Hanratty (1996).