L’impact du climat sur les variations des glaciers alpins depuis 100 ans

The Climate change impact on alpine glaciers over the last 100 years

Laboratoire de Glaciologie et de Géophysique de l’Environnement Centre National de la Recherche Scientifique 38402 Saint Martin d’Hères Cedex, BP 96, France

Auteur de correspondance : vincent@lgge.obs.ujf-grenoble.fr

Abstract

The topic of this paper is to analyze the glacier mass balance measurements over the last 100 years in the Alps and to study the climatic origin of these fluctuations. Using the longest mass balance series, this study shows that cumulative mass balance fluctuations are very similar over the last 50 years and it reveals a common climatic signal over the entire region. The annual mass balances are primarily driven by the summer ablation. Moreover, the ablation changes result from a very large energy flux rise at the glacier surface over the last two decades. Conversely, very high elevation glaciated areas, above 4200 m a.s.l., are not affected by this warming.