Meteorological controls on snow and ice ablation for two contrasting months on Glacier de Saint-Sorlin, France

Delphine Six (1) , Patrick Wagnon (1) , Jean-Emmanuel Sicart (2) , Christian Vincent (1)

1 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
2 GREATICE - Glaciers et ressources en eau d'altitude - Indicateurs climatiques et environnementaux

The influence of meteorological variables on snow/ice melting has been analyzed for two very contrasting months, in summer 2006, on Glacier de Saint-Sorlin, French Alps. July 2006 was the warmest July since 1950, and August 2006 was the coldest August since 1979. The total energy available for melting was just over half as much in August as in July, due to a sharp decrease in net shortwave radiation and in turbulent flux. This decrease of net shortwave radiation was mainly controlled by a strong increase in albedo responsible for an increase of reflected shortwave radiation, as well as by a reduction in incident shortwave radiation. During the two months, net longwave radiation remained almost unchanged. The mass balance computed from energy-balance modelling or with a degree-day approach was in good agreement with measured mass balance. Differences were attributed to space and time surface aspect variations which mainly controlled the observed mass balance.

Domaines: Glaciologie

Delphine Six, Patrick Wagnon, Jean-Emmanuel Sicart, Christian Vincent. Meteorological controls on snow and ice ablation for two contrasting months on Glacier de Saint-Sorlin, France. Annals of Glaciology, 2009, 50 (50), pp.66-72. ⟨10.3189/172756409787769537⟩. ⟨insu-00420643⟩