HR: 0800h
AN: C31A-0286    [Abstracts]
TI: Linking an Energy-Balance Snow Model (SNOBAL) to a Soil Temperature and Moisture Model (SHAW)
AU: * Davidov, S
EM: stefand@uidaho.edu
AF: Department of Civil Engineering, University of Idaho, 800 Park Blvd, suite 105, Boise, ID 83712-7716 United States
AU: Marks, D
EM: danny@nwrc.ars.usda.gov
AF: USDA-ARS Northwest Watershed Research Center, 800 Park Blvd, Suite 105, Boise, ID 83712-7716 United States
AU: Flerchinger, G
EM: gflerchi@nwrc.ars.usda.gov
AF: USDA-ARS Northwest Watershed Research Center, 800 Park Blvd, Suite 105, Boise, ID 83712-7716 United States
AU: Garen, D
EM: DGaren@wcc.nrcs.usda.gov
AF: USDA-NWRC, National Water And Climate Center, 101 SW Main Street, Suite 1600, Portland, OR 97204-3224 United States
AB: Accurate estimates of streamflow from mountain basins require an accounting for linkages between snow deposition and melt, and the moisture and temperature state of the soil. Though detailed snow deposition, energy state, and melt have been effectively simulated over mountain basins up to 2500 km$^{2}$ in the western US, equivalent soil moisture and temperature simulation has been limited to small plots or lumped extensions using land cover features over experimental catchments. As a step toward development of a fully coupled snow-soil energy and water balance model, we are testing a loose coupling of two models - SNOBAL for snowmelt and SHAW for below-ground temperature and moisture. This will involve forcing the below-ground component of SHAW with the output from SNOBAL, and will be limited to snow season conditions for this test. The objective of the initial coupling will be to determine the reliability of the simulation compared to measured conditions, and the sensitivity of the simulated snow-soil system to explicit rather than coupled feed-backs between the models. While the snowmelt model offers a numerically stable two-layer explicit solution that has been effectively extended over solution grids of 500,000 cells or more, the soil model uses a more numerically demanding central difference approach in which the number of nodes and layers vary with time and conditions. An objective of the test coupling of these models will be to determine how to simplify the representation of the soil thermal and moisture system, and still achieve an acceptable simulation of soil moisture and temperature. This research will result in the design requirements for a fully coupled snow-soil energy and water balance model that will improve our ability to manage limited water resources in the inter-mountain western US.
DE: 1863 Snow and ice (1827)
DE: 1878 Water/energy interactions
SC: Cryosphere [C]
MN: 2004 AGU Fall Meeting