Water resources managers require improved methods for assessing the sensitivity of the systems they manage to seasonal and longer- term variations in weather and climate. Equally important is the need for methods of evaluating the risk or uncertainty associated with such assessments. Virtually all techniques of hydrologic analysis are based on the assumption of a stationary, or unchanging climate.
Climate modeling is limited by physical understanding and the speed of existing computers.
Hydrologic models have traditionally been more focused on the problem of flood responses and not the overall water budget. The objective of this program is to develop a capability to predict the hydrometeorological and water resources response to climate variability and change across the range of environmental conditions existing in the United States. This is providing Federal, State, and local water resource managers with the tools and techniques to improve management of existing water supplies. The BOR is working with the National Center for Atmospheric Research on the nesting of atmospheric models to improve prediction of hydrometeorological variables. The USGS is working under cooperative agreements with the governments of Japan and Russia on the development of improved watershed models.