The morphodynamics of the mont blanc massif in a changing cryosphere: a comprehensive review

International audience One of the most glacierized areas in the European Alps, the Mont Blanc massif, illustrates how fast changes affect the cryosphere and the related morphodynamics in high mountain environments, especially since the termination of the Little Ice Age. Contrasts between the north-w...

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Bibliographic Details
Published in:Geografiska Annaler: Series A, Physical Geography
Main Authors: Deline, Philip, Gardent, Marie, Magnin, Florence, Ravanel, Ludovic
Other Authors: Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Institut de Géographie Lausanne (IGUL), Université de Lausanne (UNIL)
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2012
Subjects:
Ice
Online Access:https://hal.archives-ouvertes.fr/halsde-00757235
https://doi.org/10.1111/j.1468-0459.2012.00467.x
Description
Summary:International audience One of the most glacierized areas in the European Alps, the Mont Blanc massif, illustrates how fast changes affect the cryosphere and the related morphodynamics in high mountain environments, especially since the termination of the Little Ice Age. Contrasts between the north-west side, gentle and heavily glaciated, and the south-east side, steep and rocky, and between local faces with varying slope angle and aspect highlight the suitability of the study site for scientific investigations. Glacier shrinkage is pronounced at low elevation but weaker than in other Alpine massifs, and supraglacial debris covers have developed over most of the glaciers, often starting in the nineteenth century. Lowering of glacier surface also affects areas of the accumulation zone. While modern glaciology has been carried out in the massif for several decades, study of the permafrost has been under development for only a few years, especially in the rock walls. Many hazards are related to glacier dynamics. Outburst flood from englacial pockets, ice avalanche from warm-based and cold-based glaciers, and rock slope failure due to debuttressing are generally increasing with the current decrease or even the vanishing of glaciers. Permafrost degradation is likely involved in rockfall and rock avalanche, contributing to the chains of processes resulting from the high relief of the massif. The resulting hazards could increasingly endanger population and activities of the valleys surrounding the Mont Blanc massif.