Shorter snow cover duration since 1970 in the Swiss Alps due to earlier snowmelt more than to later snow onset

摘要: Global warming has strong impacts on snow cover, which in turn affects ecosystems, hydrological regimes and winter tourism. Only a few long-term series are available worldwide, especially at high elevation. Here, we analyzed several snowpack characteristics over the period 1970–2015 eleven meteorological stations, spanning elevations from 1139 to 2540 m asl Swiss Alps. Snow cover duration significantly shortened all sites, average by 8.9 days decade−1. This shortening was largely driven earlier snowmelt (on average 5.8 days decade−1) partly later onset but latter significant only ~30 % of stations. On average, season now starts 12 days ends 26 days than 1970. Overall, annual maximum depth declined 3.9 10.6 % decade−1 reached 7.8 ± 0.4 12.0 ± 0.4 days earlier, though these trends hide inter-annual decadal variability. The number days with ground also decreased elevations, regions for thresholds 1 100 cm. our results demonstrate marked decline parameters, irrespective elevation region, whether drier or wetter locations, pronounced shift spring, connection reinforced during this season.