American Geophysical Union, Geophysical Research Letters, 7(38), p. n/a-n/a, 2011
DOI: 10.1029/2011gl046976
Full text: Unavailable
1] This paper analyzes the proportion of snowfall days relative to precipitation days, in order to assess the impact of changing temperatures on snowfall, while minimizing the impact of variations in precipitation frequency and intensity. We analyzed the ratio of snowfall days to precipitation days for up to 100 years at 76 meteorological stations, spanning elevations from 200 to 2700 m asl in Switzerland. Our re-sults show clear decreasing trends in snowfall days relative to precipitation days. These decreases are connected to increasing temperatures. The decrease in snowfall days was stronger at lower elevations, i.e., at locations with tem-peratures closer to the melting point. We observed a baseline seasonal temperature threshold of −2.7°C ± 0.8°C in winter and −3.8°C ± 0.6°C in spring, above which the decrease in snowfall days grew rapidly. From these observations, we developed an empirical model that can be used to evaluate the impact of future temperature increases on snowfall, inde-pendent of changes in the frequency and intensity of precip-itation events.