INTEGRATING SNOW MANAGEMENT PROCESSES AND PRACTICES INTO A DETAILED SNOW- PACK MODEL. RELEVANCE, APPLICATIONS AND PROSPECTS

G rowing environmental concerns and the ongoing economic crisis push ski resorts operators to pay greater attention to water and energy consumptions and at the same time climate change raises worrying questions about the future of snow industry. Demand for optimization and diagnostics have been growing quickly among professionals and policy makers while paradoxically snow management strategies and impacts on snowpack properties have so far drawn sporadic interest in terms of scientific research. Here we introduce a new numerical tool for snow management analysis and simulation based on the SAFRANCrocus model chain. We present the first step of the integration of snow management (snowmaking, grooming) into the detailed snowpack model Crocus. Several ski resorts in the French Alps were interviewed to collect data about machine-made snow production (water volumes, periods of production, snowmaking constraints, etc.) and to assess standard practices (work schedules, priority periods and extra constraints), which we implemented in the model. SAFRAN-Crocus runs provide realistic and consistent results when compared to observations by professionals. Machine-made snow production occurs in the model depending on a predefined production scheme and meteorological constraints (wind, wet-bulb temperature). Machine made snow properties are set to commonly observed properties in terms of density and microstructure characteristics, which differ widely from natural fresh snow properties. Simulation results from Les 2Alpes resort (Oisans, French Alps) illustrate the first results. Accounting for machinemade snow production leads to significant enhancement of snowpack conditions for skiing (increased depth and mass) and the season length is extended. The densification due to grooming has also been investigated and shows a significant effect on thermal properties of the snowpack. The season length is also extended thanks to the densification of the snowpack. Overall, the introduction of snow management practices in Crocus appears as a potentially powerful tool to simulate snow conditions on ski resorts tracks. Promising outlooks are presented, among which a diagnostic of resorts ability to face climate change including snow management practices accounting for technical, environmental and regulatory constraints (e.g. water volumes optimization, grooming schedule, etc.).