HR: 1340h
AN: H23D-1160    [Abstracts]
TI: River Basin Water Balance Estimates of Evapotranspiration Using GRACE and Other Observations
AU: * Rodell, M
EM: Matthew.Rodell@nasa.gov
AF: NASA Goddard Space Flight Center, Hydrological Science Branch, Code 974.1, Greenbelt, MD 20771 United States
AU: Famiglietti, J S
EM: jfamigli@uci.edu
AF: University of California, Irvine, Department of Earth System Science, Irvine, CA 92697
AU: Chen, J
EM: chen@csr.utexas.edu
AF: The University of Texas at Austin, Center for Space Research, Austin, TX 78759
AU: Seneviratne, S
EM: senevira@janus.gsfc.nasa.gov
AF: University of Maryland, Baltimore County, Goddard Earth Science and Technology Center, Greenbelt, MD 20771
AU: Viterbo, P
EM: pedro.viterbo@ecmwf.int
AF: ECMWF, European Center for Medium-Range Weather Forecasts, Reading, RG2 9AX United Kingdom
AU: Holl, S
EM: sholl@uci.edu
AF: University of California, Irvine, Department of Earth System Science, Irvine, CA 92697
AU: Wilson, C R
EM: crwilson@mail.utexas.edu
AF: The University of Texas at Austin, Department of Geological Sciences, Austin, TX 78757
AB: Evapotranspiration links the global cycles of water, energy, and carbon, thus it is integral to Earth system science. However, it is difficult to estimate on regional, climatic scales. One approach is to use a water budget equation, i.e., total precipitation minus the sum of evapotranspiration and net runoff equals the change in terrestrial water storage. Gravity Recovery and Climate Experiment (GRACE) satellite observations of Earth's gravity field are enabling closure of this equation by providing the terrestrial water storage change term, which has been even more elusive than evapotranspiration until now. Here we describe the method for estimating evapotranspiration using data from GRACE along with observation based precipitation and runoff, which takes into account the unique nature of the GRACE observations. GRACE water storage changes are first substantiated by comparison with results from a land surface model and a combined atmospheric-terrestrial water budget approach. Evapotranspiration is then estimated over the Mississippi River basin and compared with output from the land surface model and two operational atmospheric modeling systems. Results suggest that the new technique provides skill in evaluating modeled evapotranspiration, particularly in terms of bias.
DE: 1818 Evapotranspiration
DE: 1833 Hydroclimatology
DE: 1836 Hydrologic budget (1655)
DE: 1223 Ocean/Earth/atmosphere interactions (3339)
DE: 1640 Remote sensing
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting