Dataset Direct Download Service (WFS): Areas where natural snow is guaranteed in Haute-Savoie

Parts of the envelope of ski areas where natural snow is guaranteed, according to different scenarios of global warming. The current guaranteed natural snow zone is empirically defined “expert” in the light of past and current snow conditions (1980-2010). Its lower limit fluctuates with guidance (N, E, SE, S, SO, O). It is fixed for all the massifs of Haute-Savoie (the massifs Haut-Savoyards having a relatively homogeneous character from a meteorological point of view, and therefore logically, from a nivological point of view) at an altitude of 1,500 meters on the north facing and goes back to 1,800 meters facing south. Within the area, the snow is “guaranteed”: ski area operators and skiers can count from year to year on sufficient snow cover from mid-December to mid-April with a probability close to 1. This concept of guaranteed natural snow makes it possible to assess the degree of exposure to snow hazards in the ski areas of Haute-Savoie. It was used as part of a reflection on the potential interactions between climate change and snow resources in winter sports stations. In a forward-looking approach, DDT74 attempted to assess the future likelihood of snow in the ski areas of Haute-Savoie by simulating the consequences of global warming on the current guaranteed natural snow zone. These simulations result in a rise of the lower limit of the current zone of 150 metres per additional degree Celsius. Three warming scenarios were applied to the current guaranteed snow zone (+ 1 °C, + 2 °C and + 4 °C), to define three new “fictitious” areas of guaranteed natural snow.