Influence of environmental factors on snow gliding prior to and after a first snowfall event

Davos

2022

1 S.

Sonderdruck

13068S

40003729

Abstract Despite the fact that snow gliding and glide avalanches have been thoroughly studied, they remain fairly unpredictable by the current methodology. There is a growing body of evidence that the environmental conditions in late autumn affect gliding activity in the following winter. In this study we analyze the effect of 67 independent variables, including variables that characterize the autumn conditions, on snow gliding by using ordinary least square regression. The analysis shows that the cumulative soil temperature (at 10 cm depth) summed for 3 weeks before a permanent snow-cover formation, the soil temperature at 10 cm depth, the soil water content at 0 cm depth, the cumulative air temperature summed for 1 month before a permanent snow cover formation and the daily minimum snow liquid-water content (LWC) significantly influence snow gliding. These results confirm our hypothesis that conditions preceding the formation of a permanent snow cover affect snow gliding. Furthermore, our findings suggest that stored heat in the soil is responsible for inducing water phase changes which are a source of liquid water at the snow–soil interface and promote gliding. Based on this and previous studies, we conclude that it is beneficial for further investigations to gather snow-gliding data for multiple seasons and differentiate between gliding and nongliding events, as well as between cold- and warm-temperature gliding events.