Climatic Research Unit

Regional case studies

Changes in snow cover over the Alps

The ENSEMBLES RCMs indicate that by 2100 snow cover is reduced all over Europe and will have almost completely disappeared in southern and western Europe. In the Alps, the decrease is much smaller above 2000m. Kotlarski et al., 2009.

Change of mean winter snow water equivalent in the European Alps (2070-2099 minus 1970-1999) versus orography. Shown are the ensemble mean, minimum and maximum based on six ENSEMBLES regional climate change scenarios (DMI, ETHZ, HC, KNMI, MPI, SMHI) assuming SRES A1B emissions.

The ENSEMBLES regional climate change scenarios were analysed with respect to projected changes in European snow cover with an emphasis on the European Alps (Kotlarski et al., 2009). In this region, snow cover strongly influences the annual cycle of river discharge and is of major socio-economic importance (e.g., for tourism). All investigated RCMs agree on the fact that, by 2100, snow cover is reduced all over Europe and will have almost completely disappeared in southern and western Europe. In the European Alps, a distinct elevation gradient of percentage changes in snow water equivalent (swe) appears: low-lying areas will experience an swe loss of 80% or more, while the swe decrease is much smaller in regions above 2000m. One reason for this is the compensation of higher winter temperatures by projected increases of wintertime precipitation in high-elevation regions.

Kotlarski, S., Lüthi, D. and Schär, C., 2009: Future changes of European snow cover as simulated by an ensemble of regional climate models. In preparation.

 

return to top