Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps
Glacier retreat results in major landscape changes including the formation of new lakes in Glacier-Bed Overdeepenings (GBOs) that can provoke catastrophic Glacial Lake Outburst Flood (GLOF) hazards, but could also provide economic opportunities. This study aims to identify and characterize the locat...
Published in: | Géomorphologie : relief, processus, environnement |
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2021
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Online Access: | http://journals.openedition.org/geomorphologie/15255 |
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fttriple:oai:gotriple.eu:oai:revues.org:geomorphologie/15255 2023-05-15T16:38:23+02:00 Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps Cathala, Maeva Magnin, Florence Linsbauer, Andreas Haeberli, Wilfried 2021-05-03 http://journals.openedition.org/geomorphologie/15255 undefined unknown Groupe français de géomorphologie Géomorphologie : relief, processus, environnement urn:doi:10.4000/geomorphologie.15255 http://journals.openedition.org/geomorphologie/15255 undefined Désenglacement des paysages surcreusements glaciaires futurs lacs potentiels Alpes françaises anticipation des aléas naturels Deglaciating landscapes Glacier Bed Overdeepenings potential future lakes French Alps hazards anticipation geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2021 fttriple https://doi.org/10.4000/geomorphologie.15255 2023-01-22T19:03:22Z Glacier retreat results in major landscape changes including the formation of new lakes in Glacier-Bed Overdeepenings (GBOs) that can provoke catastrophic Glacial Lake Outburst Flood (GLOF) hazards, but could also provide economic opportunities. This study aims to identify and characterize the location of potential GBOs in the French Alps as possible sites for future lakes. We first ran GlabTop (Glacier-bed Topography) and GlabTop2 models, two GIS schemes calculating glacier ice thickness and mapping potential GBOs. Their level of confidence is estimated using morphological analysis based on slope angle, crevasse fields and lateral narrowing at bedrock thresholds. 139 GBOs (>0.01km²) were predicted among which 59 have medium to very high confidence. 20 lakes are already forming at the snout of retreating glaciers, including four lakes at predicted GBOs <0,01km². The Vanoise massif hosts 43% of the predicted GBOs but the Mont Blanc massif gathers larger, deeper and more voluminous ones. Most of the predicted GBOs are below 3,500m a.s.l. as related to the elevation of the corresponding glaciers. In the Vanoise massif, many predicted GBOs have rather low confidence because of the extent of ice-cap like glaciers for which the shear stress approach used by GlabTop becomes questionable. Furthermore, 58 potential GBOs were detected by visual analysis of glacier morphologies. The study highlights the relevance of combining various methods to determine GBOs and is a first step towards the anticipation of future risks and opportunities related to the formation of new lakes in the French Alps. Dans le contexte actuel de retrait glaciaire, de nouveaux lacs se forment parfois dans les surcreusements des lits glaciaires. Ces lacs peuvent provoquer ou amplifier des aléas naturels (e.g., vidange brutale d’un lac) ou être source d’opportunités économiques. Cette étude vise à identifier et caractériser les surcreusements glaciaires pour déterminer les futurs lacs potentiels dans les Alpes françaises. La topographie sous ... Article in Journal/Newspaper Ice cap Unknown Four Lakes ENVELOPE(-126.826,-126.826,54.858,54.858) Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) Mont Blanc ENVELOPE(69.468,69.468,-49.461,-49.461) New Lakes ENVELOPE(177.649,177.649,51.951,51.951) Géomorphologie : relief, processus, environnement 27 1 19 36 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
unknown |
topic |
Désenglacement des paysages surcreusements glaciaires futurs lacs potentiels Alpes françaises anticipation des aléas naturels Deglaciating landscapes Glacier Bed Overdeepenings potential future lakes French Alps hazards anticipation geo envir |
spellingShingle |
Désenglacement des paysages surcreusements glaciaires futurs lacs potentiels Alpes françaises anticipation des aléas naturels Deglaciating landscapes Glacier Bed Overdeepenings potential future lakes French Alps hazards anticipation geo envir Cathala, Maeva Magnin, Florence Linsbauer, Andreas Haeberli, Wilfried Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
topic_facet |
Désenglacement des paysages surcreusements glaciaires futurs lacs potentiels Alpes françaises anticipation des aléas naturels Deglaciating landscapes Glacier Bed Overdeepenings potential future lakes French Alps hazards anticipation geo envir |
description |
Glacier retreat results in major landscape changes including the formation of new lakes in Glacier-Bed Overdeepenings (GBOs) that can provoke catastrophic Glacial Lake Outburst Flood (GLOF) hazards, but could also provide economic opportunities. This study aims to identify and characterize the location of potential GBOs in the French Alps as possible sites for future lakes. We first ran GlabTop (Glacier-bed Topography) and GlabTop2 models, two GIS schemes calculating glacier ice thickness and mapping potential GBOs. Their level of confidence is estimated using morphological analysis based on slope angle, crevasse fields and lateral narrowing at bedrock thresholds. 139 GBOs (>0.01km²) were predicted among which 59 have medium to very high confidence. 20 lakes are already forming at the snout of retreating glaciers, including four lakes at predicted GBOs <0,01km². The Vanoise massif hosts 43% of the predicted GBOs but the Mont Blanc massif gathers larger, deeper and more voluminous ones. Most of the predicted GBOs are below 3,500m a.s.l. as related to the elevation of the corresponding glaciers. In the Vanoise massif, many predicted GBOs have rather low confidence because of the extent of ice-cap like glaciers for which the shear stress approach used by GlabTop becomes questionable. Furthermore, 58 potential GBOs were detected by visual analysis of glacier morphologies. The study highlights the relevance of combining various methods to determine GBOs and is a first step towards the anticipation of future risks and opportunities related to the formation of new lakes in the French Alps. Dans le contexte actuel de retrait glaciaire, de nouveaux lacs se forment parfois dans les surcreusements des lits glaciaires. Ces lacs peuvent provoquer ou amplifier des aléas naturels (e.g., vidange brutale d’un lac) ou être source d’opportunités économiques. Cette étude vise à identifier et caractériser les surcreusements glaciaires pour déterminer les futurs lacs potentiels dans les Alpes françaises. La topographie sous ... |
format |
Article in Journal/Newspaper |
author |
Cathala, Maeva Magnin, Florence Linsbauer, Andreas Haeberli, Wilfried |
author_facet |
Cathala, Maeva Magnin, Florence Linsbauer, Andreas Haeberli, Wilfried |
author_sort |
Cathala, Maeva |
title |
Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
title_short |
Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
title_full |
Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
title_fullStr |
Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
title_full_unstemmed |
Modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating French Alps |
title_sort |
modelling and characterizing glacier-bed overdeepenings as sites for potential future lakes in the deglaciating french alps |
publisher |
Groupe français de géomorphologie |
publishDate |
2021 |
url |
http://journals.openedition.org/geomorphologie/15255 |
long_lat |
ENVELOPE(-126.826,-126.826,54.858,54.858) ENVELOPE(-129.463,-129.463,58.259,58.259) ENVELOPE(69.468,69.468,-49.461,-49.461) ENVELOPE(177.649,177.649,51.951,51.951) |
geographic |
Four Lakes Glacial Lake Mont Blanc New Lakes |
geographic_facet |
Four Lakes Glacial Lake Mont Blanc New Lakes |
genre |
Ice cap |
genre_facet |
Ice cap |
op_relation |
urn:doi:10.4000/geomorphologie.15255 http://journals.openedition.org/geomorphologie/15255 |
op_rights |
undefined |
op_doi |
https://doi.org/10.4000/geomorphologie.15255 |
container_title |
Géomorphologie : relief, processus, environnement |
container_volume |
27 |
container_issue |
1 |
container_start_page |
19 |
op_container_end_page |
36 |
_version_ |
1766028663740956672 |