Skip to Main content Skip to Navigation
Theses

Inventaire et retrait des glaciers dans les alpes françaises depuis la fin du Petit Age Glaciaire

Abstract : French alpine glaciers are retreating since the end of the Little Ice Age (LIA). In the context of the increasing air temperature and because of issues that they represent, it is necessary to improve glacier monitoring. Before the present study, the only two inventories covering the entire French Alps were made by Mougin (1925) and Vivian (1975). The main goal of this study is to realise a multi-temporal glacier inventory of glaciers in the French Alps and of their proglacial margins. Data from this inventory are used to study glacial retreat since the end of the LIA and to develop methods to detect sector that could be affected by instabilities. Multi-temporal inventory of French Alpine glacier glaciers is made for 3 dates: (i) 2006-2009, based on IGN recent orthophotographs, (ii) 1967-1971, based on 1: 25 000 IGN topographic maps, and (iii) the end of the LIA (for Mont Blanc, Vanoise and Ecrins massifs), crossing old documents and geomorphologic data based on field work and interpretation of orthophotographs. Data are integrated in a Geographical Information System (GIS), combining mapping and data base. Glaciers in the French Alps covered 275 km² in 2006-2009, 369 km² in 1967-1971 and 544 km² at the end of the LIA for Mont Blanc, Vanoise and Ecrins massifs. At a regional scale, glaciers lost 25 % of their 1967-1971 area and 50 % of their LIA area. Glacier shrinkage between 1967-1971 and 2006-2009 is about 2.5 times higher than between the end of the LIA and 2006-2009. At an individual scale glaciers lost 52 % of their area between 1967-1971 and 2006-2009, and 115 disappeared. At regional or individual scale, different trends in glacier shrinkage are observed according to the massifs, size and aspect of the glaciers. Simple methods, based on glaciers inventory and proglacial margins data, are developed in order to identify potential unstable lakes, glaciated sectors prone to glacier lake formation, ice avalanche triggering or mass destabilization, and proglacial margins where sliding or debris flows could occur.
Document type :
Theses
Complete list of metadata

https://tel.archives-ouvertes.fr/tel-01062226
Contributor : ABES STAR :  Contact
Submitted on : Tuesday, September 9, 2014 - 2:37:13 PM
Last modification on : Friday, March 25, 2022 - 9:44:25 AM
Long-term archiving on: : Wednesday, December 10, 2014 - 1:35:37 PM

File

These_Gardent_Marie_2014.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01062226, version 1

Collections

Citation

Marie Gardent. Inventaire et retrait des glaciers dans les alpes françaises depuis la fin du Petit Age Glaciaire. Géographie. Université de Grenoble, 2014. Français. ⟨NNT : 2014GRENA008⟩. ⟨tel-01062226⟩

Share

Metrics

Record views

1321

Files downloads

4096