Estimates of snow accumulation and volume in the Swiss Alps under changing climatic conditions

Abstract

Snow is a key feature of mountain environments in terms of the controls it exerts on hydrology, vegetation, and in terms of its economic significance (e.g., for the ski industry). Its quantification in a changing climate is thus important for various environmental and economic impact assessments. Based on observational analysis, surface energy balance modeling, and the latest data from high-resolution regional climate models, this paper investigates the possible changes in snow volume and seasonality in the Swiss Alps. An average warming of 4°C as projected for the period 2071-2100 with respect to current climate suggests that snow volume in the Alps may respond by reductions of at least 90% at altitudes close to 1000 m, by 50% at 2000 m, and 35% at 3000 m. In addition, the duration of snow cover is sharply reduced in the warmer climate, with a termination of the season 50-60 days earlier at high elevations above 2000-2500 m and 110-130 days earlier at medium elevation sites close to the 1000 m altitude. The shortening of the snow season concerns more the end (spring) rather than the beginning (autumn), so that it should be expected that snow melt will intervene much earlier in the season than under current conditions. The results of this study are of relevance to the estimations of the impacts that the projected warming may have on the amount and timing of water in hydrological basins, on the start of the vegetation season, and on the financial status of many mountain resorts.

The changing roles of temperature and precipitation on snowpack variability in Switzerland as a function of altitude

“…The snowpack also controls the timing and amount of seasonal runoff in alpine rivers and has a direct influence on the energy sector through hydropower [Rahman et al, 2012], which is the most important source of electricity in alpine countries [Romerio, 2002]. The decrease in the number of snow days in Switzerland since the late 1980s [Scherrer et al, 2004;Marty, 2008], and the expected decline in conditions appropriate for snow formation and retention under warmer climate conditions [Beniston et al, 2003b], are a source of concern for investors and policy makers on the future viability of these sectors.…”

Snowmelt infiltration and storage within a karstic environment, Vers Chez le Brandt, Switzerland

“…With increased global temperature, the hydrologic cycle could undergo significant alteration including possible reductions in seasonal snow cover (Beniston et al, 2003) and shifts in amount and type of precipitation (Arnell, 2001). Alterations in these parameters would invariable affect the volumetric and temporal distribution of groundwater recharge, particularly in cold-regions (Eckhardt and Ulbrich, 2003).…”

Trends in Swiss Alpine snow days: The role of local‐ and large‐scale climate variability

“…[2] Snow is a resource of great commercial and social value for the Swiss Alpine region (tourism, drinking water reservoir, hydro-electricity) but it also bears considerable hazards (avalanches, road closures) [e.g., Beniston et al, 2003;Elsasser and Messerli, 2001]. However, the number of snow days (SD) varies substantially on interannual to decadal time scales.…”