Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises
Alpine mountains are affected by significant geomorphological processes whose evolution is partly conditioned by permafrost warming: rockfalls of various volumes, destabilisation of rock glaciers, and cryokarst. These phenomena, because of their intensity, may generate risks for territories. This pa...
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Institut de Géographie Alpine
2015
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ftdoajarticles:oai:doaj.org/article:dd5623f3284d41f9a6e0237c010867f3 2023-05-15T17:56:23+02:00 Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises Xavier Bodin Philippe Schoeneich Philip Deline Ludovic Ravanel Florence Magnin Jean-Michel Krysiecki Thomas Echelard 2015-09-01T00:00:00Z https://doi.org/10.4000/rga.2806 https://doaj.org/article/dd5623f3284d41f9a6e0237c010867f3 EN FR eng fre Institut de Géographie Alpine http://journals.openedition.org/rga/2806 https://doaj.org/toc/0035-1121 https://doaj.org/toc/1760-7426 0035-1121 1760-7426 doi:10.4000/rga.2806 https://doaj.org/article/dd5623f3284d41f9a6e0237c010867f3 Revue de Géographie Alpine, Vol 103, Iss 2 (2015) permafrost French Alps geomorphological dynamics climate change Geography. Anthropology. Recreation G Physical geography GB3-5030 article 2015 ftdoajarticles https://doi.org/10.4000/rga.2806 2022-12-31T06:52:21Z Alpine mountains are affected by significant geomorphological processes whose evolution is partly conditioned by permafrost warming: rockfalls of various volumes, destabilisation of rock glaciers, and cryokarst. These phenomena, because of their intensity, may generate risks for territories. This paper provides a synthesis of the knowledge about the current status of the mountain permafrost in the French Alps and its recent evolution. This state-of-the-art overview is based on research conducted over the past 10 years and the measurements collected within PermaFRANCE, the French network for long-term observation of the mountain permafrost. The analysis of the available data shows that for a rock wall located at 3800 m asl., the temperature is between -4.5 and -1.5°C at a depth of 10 m, according to the aspect, whereas it is close to the melting point in surficial deposits at 2800 m asl. on a northern slope. Since the beginning of these measurements at depth in 2010, a trend of increasing temperature has been discernible, as found in other alpine boreholes. As clearly shown by the surface measurements conducted since 2003, the thermal regime is influenced by snow, particularly in surficial deposits and to a much lesser extent in rock walls. This inter-annual variability is combined with longer-term trends, which probably induce the observed changes in geomorphological dynamics associated with alpine permafrost: an increased frequency of gravitational processes such as rockfalls and fluctuation in rock glacier velocities. The possible increase in extreme events, such as rock avalanches or the destabilisation of rock glaciers, in the coming decades could create new or increased risks, to which territories must thus adapt. Article in Journal/Newspaper permafrost Directory of Open Access Journals: DOAJ Articles Revue de géographie alpine 103-2 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English French |
topic |
permafrost French Alps geomorphological dynamics climate change Geography. Anthropology. Recreation G Physical geography GB3-5030 |
spellingShingle |
permafrost French Alps geomorphological dynamics climate change Geography. Anthropology. Recreation G Physical geography GB3-5030 Xavier Bodin Philippe Schoeneich Philip Deline Ludovic Ravanel Florence Magnin Jean-Michel Krysiecki Thomas Echelard Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
topic_facet |
permafrost French Alps geomorphological dynamics climate change Geography. Anthropology. Recreation G Physical geography GB3-5030 |
description |
Alpine mountains are affected by significant geomorphological processes whose evolution is partly conditioned by permafrost warming: rockfalls of various volumes, destabilisation of rock glaciers, and cryokarst. These phenomena, because of their intensity, may generate risks for territories. This paper provides a synthesis of the knowledge about the current status of the mountain permafrost in the French Alps and its recent evolution. This state-of-the-art overview is based on research conducted over the past 10 years and the measurements collected within PermaFRANCE, the French network for long-term observation of the mountain permafrost. The analysis of the available data shows that for a rock wall located at 3800 m asl., the temperature is between -4.5 and -1.5°C at a depth of 10 m, according to the aspect, whereas it is close to the melting point in surficial deposits at 2800 m asl. on a northern slope. Since the beginning of these measurements at depth in 2010, a trend of increasing temperature has been discernible, as found in other alpine boreholes. As clearly shown by the surface measurements conducted since 2003, the thermal regime is influenced by snow, particularly in surficial deposits and to a much lesser extent in rock walls. This inter-annual variability is combined with longer-term trends, which probably induce the observed changes in geomorphological dynamics associated with alpine permafrost: an increased frequency of gravitational processes such as rockfalls and fluctuation in rock glacier velocities. The possible increase in extreme events, such as rock avalanches or the destabilisation of rock glaciers, in the coming decades could create new or increased risks, to which territories must thus adapt. |
format |
Article in Journal/Newspaper |
author |
Xavier Bodin Philippe Schoeneich Philip Deline Ludovic Ravanel Florence Magnin Jean-Michel Krysiecki Thomas Echelard |
author_facet |
Xavier Bodin Philippe Schoeneich Philip Deline Ludovic Ravanel Florence Magnin Jean-Michel Krysiecki Thomas Echelard |
author_sort |
Xavier Bodin |
title |
Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
title_short |
Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
title_full |
Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
title_fullStr |
Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
title_full_unstemmed |
Le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les Alpes françaises |
title_sort |
le permafrost de montagne et les processus géomorphologiques associés : évolutions récentes dans les alpes françaises |
publisher |
Institut de Géographie Alpine |
publishDate |
2015 |
url |
https://doi.org/10.4000/rga.2806 https://doaj.org/article/dd5623f3284d41f9a6e0237c010867f3 |
genre |
permafrost |
genre_facet |
permafrost |
op_source |
Revue de Géographie Alpine, Vol 103, Iss 2 (2015) |
op_relation |
http://journals.openedition.org/rga/2806 https://doaj.org/toc/0035-1121 https://doaj.org/toc/1760-7426 0035-1121 1760-7426 doi:10.4000/rga.2806 https://doaj.org/article/dd5623f3284d41f9a6e0237c010867f3 |
op_doi |
https://doi.org/10.4000/rga.2806 |
container_title |
Revue de géographie alpine |
container_issue |
103-2 |
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1766164538965622784 |