Assessment of the snow-cover numerical model crocus-application to avalanches and hydrology

• Main Author: Mingo, Laurent
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/4231

The French snow-cover numerical model CROCUS was tested with respect to avalanche forecasting issues and hydrological applications under two specific climatic conditions. Mt. Fidelity at Glacier National Park (Selkirk Mountains) and Blackcomb Mt. Resort (South coast Mountins) were chosen for the experiments. These sites are characterized by deep snow-packs (3 to 4 meter snow-pack is common) with moderate snow-pack temperature gradients in the order of 5 °C/m. Numerous time periods can also commonly experience 10 °C/m to 15 °C/m gradients as well as isothermal temperature distributions. Such snow-pack characteristics offer the possibility to assess the performances of the model under various new conditions that differ from previously published work. CROCUS proved itself being very efficient for modeling snow-depth, density and temperature profiles, which are parameters considered important for hydrological modeling. Results show that good performance of the grain simulation is only obtained for particular ranges of snow-pack temperature gradients. For values close to 5 °C/m it is sometime difficult to achieve good simulations and the model has a tendency to mistakenly emphasize facets formation. Suggestions are proposed for the remediation of this behavior. CROCUS' heat exchanges simulations at the surface of the snow-cover were processed as an attempt to track surface hoar occurrences. Encouraging results are shown.