HR: 1340h
AN: H23C-1139    [Abstracts]
TI: Streamflow Simulations for the Mississippi River Basin Based on Ensemble Regional Climate Model Simulations
AU: * Arritt, R W
EM: rwarritt@bruce.agron.iastate.edu
AF: Iowa State University, 3010 Agronomy Hall, Ames, IA 50011 United States
AU: Jha, M
EM: manoj@iastate.edu
AF: Iowa State University, 3010 Agronomy Hall, Ames, IA 50011 United States
AU: Takle, E S
EM: gstakle@iastate.edu
AF: Iowa State University, 3010 Agronomy Hall, Ames, IA 50011 United States
AU: Gu, R
EM: roygu@iastate.edu
AF: Iowa State University, 3010 Agronomy Hall, Ames, IA 50011 United States
AB: Ensemble simulations provide a useful tool for studying uncertainties in climate projections and for deriving probabilistic information from deterministic forecasts. Although a number of studies have examined variability within climate models, fewer have quantified the extent to which variability and uncertainty in climate simulations then propagates through impacts models. Here we evaluate the variability in simulated streamflow that result from taking the streamflow model's inputs from different members of an ensemble of simulations by a decadal-scale nested regional climate model. The regional climate model, RegCM3, simulated a domain covering the continental U.S. and most of Mexico for the period 1986-2003 using initial and lateral boundary conditions from the NCEP-DOE Reanalysis 2. Three RegCM3 realizations were created, each initialized one month apart but otherwise identical in configuration so that their collective behavior provides a measure of internal variability of the climate model. RegCM3 output for daily precipitation, temperature, and radiation were then used as input to the Soil and Water Assessment Tool (SWAT) over the upper Mississippi River basin. Seasonal and interannual variability of SWAT-predicted streamflow indicate that the internal variability of the RegCM3 climate model carries through to produce spread in simulated streamflow from SWAT.
DE: 3337 Numerical modeling and data assimilation
DE: 3354 Precipitation (1854)
DE: 1833 Hydroclimatology
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting