GCIP research and the Department of Energy's Atmospheric Radiation Measuring (ARM) Program have led to improved understanding of the hydrologic cycle and evapotranspiration processes that affect water demand by vegetation; and improved forecasts of precipitation, and surface runoff processes that affect streamflow forecasts and water supplies. Much of this research is consolidated in the North American Land Data Assimilation System (NLDAS) project which involves the inter-comparison of different land surface models (LSMs), performs model simulations in a near-realtime setting, and will use different data assimilation techniques to assimilate observations into the LSMs. This study seeks to develop applications of this research for water resource managers. The Red-Arkansas River Basin is of particular interest because NOAA has also proposed this basin as a study site for the Hydrology for the Environment, Life, and Policy (HELP) Program.

An improved method for analyzing and predicting the consumptive use of water by irrigated crops and riparian vegetation is needed to make the optimal water management decisions. This effort seeks to apply different NLDAS LSMs and their output to improve real-time decision making. The approach will validate the LSMs predicted variables using Oklahoma Mesonet observations, and integrate the results into Reclamation's Agricultural Water Resources Decision Support (AWARDS) System (Hartzell et al, 1998, 2000). It will test the value of the research to improve North Fork Red River Basin catchment management during periods of drought in 2001-2002. Comparisons of the AWARDS system with and without the different LSMs output will be made to show the benefit and value of the hydrologic research to water managers. This will be provided in terms of error analysis - correlation of LSM predictions with measurements, potential water conserved, potential resulting benefits to drought mitigation, and integrated watershed management, and sustainability of scarce resources. Examples of real-time Internet-based AWARDS decision support products for water managers and irrigators will be provided.

During the summer of 2002, NLDAS operational and forecast surface energy budgets will be used to inform the farmers and irrigation districts of the current and future demand for water by their crops out to 48-72 hours using AWARDS on the Internet. These analyses and forecasts would be tested over the Lugert Altus Irrigation District in the North Fork Red River Basin in southwest Oklahoma.