Research Title: Interaction of Climate & Hydrologic Systems
Funding Level (millions of dollars):
Committee on Environment and Natural Resources (CENR) Component:
(a) Subcommittee: Global Change Subcommittee (100%)
(b) Environmental Issue: Natural Variability (100%)
(c) Research Activity: System structure and function: Understanding (50%), Observation (8%); Assessment (20%); Data Management (22%)
U.S. Geological Survey
104 National Center
Reston, VA 22092
Point of Contact:
The program objectives are to improve (1) fundamental understanding of the response of the hydrologic system to atmospheric conditions and changes, as well as the feedback effects on the atmosphere that are produced by the hydrologic system; (2) the accuracy of climate model predictions; and (3) the accuracy of the predictions of watershed and continental water balance response (streamflow, soil moisture, and ground water) to climatic variability and change.
The adequate parameterization of variables representing the terrestrial phase of the hydrologic cycle remains a major weakness of existing climate models. The transfer of water and energy to, across, and from the land surface is important both as a determinant of climate and as a determinant of water availability. A major emphasis of this program is to translate process understanding of hydrologic systems from the plot or basin scale up to continental and global scales.
The program encompasses a number of intensive field investigations at geographically diverse locations involving both monitoring of and process research on the fluxes of water and energy at the land surface, and land-atmosphere feedback mechanisms. These field investigations are known as the Water, Energy, and Biogeochemical Budgets (WEBB) studies. They involve long-term observation and modeling of the components of water and energy budgets to provide information on these interactive processes.
The USGS is deeply involved in climate modeling activities at NOAA's Geophysical Fluid Dynamics Laboratory and at the National Center for Atmospheric Research by having USGS hydrologists working as part of the research teams of both institutions on model development, testing, and verification. The USGS WEBB investigations are conducted in close collaboration with the Forest Service, National Park Service, the U.S. Army Corps of Engineers, and the National Science Foundation's Long-Term Ecological Research (LTER) sites. USGS is also playing a pivotal role in the development of the GEWEX project in the Mississippi River basin along with NOAA, NASA, and DOE.
In the near term this program will provide important guidance to policy makers on where to invest research funds to get the most improvement in climate model predictions. Over the longer-term, it will provide the understanding necessary to develop policy-relevant climate predictions.