Submitted to: Trans American Geophysical Union
Publication Type: Proceedings
Publication Acceptance Date: November 16, 1999
Publication Date: N/A
Technical Abstract: The areal distribution of snowfall impacts many aspects of river basin hydrology and biology. In mountainous terrain, the areal distribution takes on complex patterns which are difficult and expensive to monitor. We have implemented the RAMS model (Regional Atmospheric Modeling system) to predict areal distributions of snow and rain accumulations in the mountainous terrain of Idaho. Accurate simulations in rugged terrain require careful choice of input parameters and measured data assimilation criteria. As is typical in atmospheric models, the model gridded terrain in mountainous regions must be exaggerated in order to produce realistic precipitation amounts. Initial and boundary condition data are supplied through measured rawindsonde and surface data and gridded analyses. Proper weighting of these input data are critical for accurate simulation of the atmospheric moisture conditions in mountainous terrain. We are verifying the model with dual gauge snowfall accumulations from the Reynolds Creek Experimental Watershed. The model results are also being used to cross-validate NEXRAD snowfall measurements. We are starting to use the modeled snowfall data in distributed river basin hydrology models in conjunction with frozen ground estimates from RadarSat data to simulate cold season flooding.