Modelling of the densification of polar firn: characterization of the snow-firn transition

Laurent Arnaud (1) , Volodya Lipenkov (2) , Jean-Marc Barnola (1) , Michel Gay (1) , Paul Duval (1)

1 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
2 AARI - Arctic and Antarctic Research Institute

The transformation of dry snow to firn is described by the transition between densification by deformationless restacking and densification by power-law creep.The observed decrease with temperature of the density at the snow- firn transition seems to result from the competition between grain-boundary sliding and power-law creep. These two densification processess occur concurrenLly in snow, although there are probably micro-regions in which sliding alone occurs. Validation ofa geometrical densifi- cation model developed for ceramics has been obtained from densification data from several Antarctic and Greenland sites and from the characterization of the structure of polar firn.

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]; Traitement des images [eess.IV]

Laurent Arnaud, Volodya Lipenkov, Jean-Marc Barnola, Michel Gay, Paul Duval. Modelling of the densification of polar firn: characterization of the snow-firn transition. International Symposium on Snow and Avalanches, 1997, Chamonix, France. pp.39-44. ⟨hal-00927005⟩