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

• Main Authors: Arnaud, Laurent, Lipenkov, Volodya, Barnola, Jean-Marc, Gay, Michel, Duval, Paul
• Other Authors: Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Arctic and Antarctic Research Institute (AARI), Russian Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 1997
• Subjects: [PHYS.MECA.MEMA]Physics [physics]/Mechanics [physics]/Mechanics of materials [physics.class-ph]; [SPI.MECA.MEMA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of materials [physics.class-ph]; [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV]; Annals of Glaciology; Antarc*; Antarctic; Greenland
• Online Access: https://hal.science/hal-00927005; https://hal.science/hal-00927005/document; https://hal.science/hal-00927005/file/igs_annals_vol26_year1998_pg39-44.pdf

International audience 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.