Assessing the importance of snowmelt in distributed hydrologic simulations

The proper representation of physical snow processes at the regional and continental scales is crucial to accurate climate and weather simulations in the cold season. One aspect of this is the sensitivity of such representations on the hydrologic cycle. To gage this sensitivity we are using a coupled model framework linking the SSiB land-surface model (with a collection of snow sub-model variants) coupled to a ground-water model (MODFLOW) and a surface/stream flow hydrology model (CASC2D). Here, we shall focus on the Wind River Basin, Wyoming, in the GCIP LSA/NW region. This basin has a number of USGS stream gages and SnoTel stations allowing us to observe the effects of snow melt on the hydrologic cycle. Observed meteorological forcings (e.g., from atmospheric model output or reanalysis) will drive the model system over a series of sensitivity runs over the Wind River Basin. Preliminary results of these simulations will be presented.