Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought?
The detachment of large parts of low-angle mountain glaciers resulting in massive ice–rock avalanches have so far been believed to be a unique type of event, made known to the global scientific community first for the 2002 Kolka Glacier detachment, Caucasus Mountains, and then for the 2016 collapses...
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Copernicus Publications
2021
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ftunivzuerich:oai:www.zora.uzh.ch:211398 2024-06-23T07:57:10+00:00 Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? Kääb, Andreas Jacquemart, Mylène Gilbert, Adrien Leinss, Silvan Girod, Luc Huggel, Christian Falaschi, Daniel Ugalde, Felipe Petrakov, Dmitry Chernomorets, Sergey Dokukin, Mikhail Paul, Frank Gascoin, Simon Berthier, Etienne Kargel, Jeffrey S 2021-04-12 application/pdf https://www.zora.uzh.ch/id/eprint/211398/ https://www.zora.uzh.ch/id/eprint/211398/1/2021_Paul_tc-15-1751-2021.pdf https://doi.org/10.5167/uzh-211398 https://doi.org/10.5194/tc-15-1751-2021 eng eng Copernicus Publications https://www.zora.uzh.ch/id/eprint/211398/1/2021_Paul_tc-15-1751-2021.pdf doi:10.5167/uzh-211398 doi:10.5194/tc-15-1751-2021 urn:issn:1994-0416 info:eu-repo/semantics/openAccess Creative Commons: Attribution 4.0 International (CC BY 4.0) http://creativecommons.org/licenses/by/4.0/ Kääb, Andreas; Jacquemart, Mylène; Gilbert, Adrien; Leinss, Silvan; Girod, Luc; Huggel, Christian; Falaschi, Daniel; Ugalde, Felipe; Petrakov, Dmitry; Chernomorets, Sergey; Dokukin, Mikhail; Paul, Frank; Gascoin, Simon; Berthier, Etienne; Kargel, Jeffrey S (2021). Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? The Cryosphere, 15(4):1751-1785. Institute of Geography 910 Geography & travel Earth-Surface Processes Water Science and Technology Journal Article PeerReviewed info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2021 ftunivzuerich https://doi.org/10.5167/uzh-21139810.5194/tc-15-1751-2021 2024-05-29T01:12:07Z The detachment of large parts of low-angle mountain glaciers resulting in massive ice–rock avalanches have so far been believed to be a unique type of event, made known to the global scientific community first for the 2002 Kolka Glacier detachment, Caucasus Mountains, and then for the 2016 collapses of two glaciers in the Aru range, Tibet. Since 2016, several so-far unrecognized low-angle glacier detachments have been recognized and described, and new ones have occurred. In the current contribution, we compile, compare, and discuss 20 actual or suspected large-volume detachments of low-angle mountain glaciers at 10 different sites in the Caucasus, the Pamirs, Tibet, Altai, the North American Cordillera, and the Southern Andes. Many of the detachments reached volumes in the order of 10–100 million m3. The similarities and differences between the presented cases indicate that glacier detachments often involve a coincidental combination of factors related to the lowering of basal friction, high or increasing driving stresses, concentration of shear stress, or low resistance to exceed stability thresholds. Particularly soft glacier beds seem to be a common condition among the observed events as they offer smooth contact areas between the glacier and the underlying substrate and are prone to till-strength weakening and eventually basal failure under high pore-water pressure. Partially or fully thawed glacier bed conditions and the presence of liquid water could thus play an important role in the detachments. Surface slopes of the detached glaciers range between around 10∘ and 20∘. This may be low enough to enable the development of thick and thus large-volume glaciers while also being steep enough to allow critical driving stresses to build up. We construct a simple slab model to estimate ranges of glacier slope and width above which a glacier may be able to detach when extensively losing basal resistance. From this model we estimate that all the detachments described in this study occurred due to a basal shear ... Article in Journal/Newspaper The Cryosphere University of Zurich (UZH): ZORA (Zurich Open Repository and Archive |
institution |
Open Polar |
collection |
University of Zurich (UZH): ZORA (Zurich Open Repository and Archive |
op_collection_id |
ftunivzuerich |
language |
English |
topic |
Institute of Geography 910 Geography & travel Earth-Surface Processes Water Science and Technology |
spellingShingle |
Institute of Geography 910 Geography & travel Earth-Surface Processes Water Science and Technology Kääb, Andreas Jacquemart, Mylène Gilbert, Adrien Leinss, Silvan Girod, Luc Huggel, Christian Falaschi, Daniel Ugalde, Felipe Petrakov, Dmitry Chernomorets, Sergey Dokukin, Mikhail Paul, Frank Gascoin, Simon Berthier, Etienne Kargel, Jeffrey S Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
topic_facet |
Institute of Geography 910 Geography & travel Earth-Surface Processes Water Science and Technology |
description |
The detachment of large parts of low-angle mountain glaciers resulting in massive ice–rock avalanches have so far been believed to be a unique type of event, made known to the global scientific community first for the 2002 Kolka Glacier detachment, Caucasus Mountains, and then for the 2016 collapses of two glaciers in the Aru range, Tibet. Since 2016, several so-far unrecognized low-angle glacier detachments have been recognized and described, and new ones have occurred. In the current contribution, we compile, compare, and discuss 20 actual or suspected large-volume detachments of low-angle mountain glaciers at 10 different sites in the Caucasus, the Pamirs, Tibet, Altai, the North American Cordillera, and the Southern Andes. Many of the detachments reached volumes in the order of 10–100 million m3. The similarities and differences between the presented cases indicate that glacier detachments often involve a coincidental combination of factors related to the lowering of basal friction, high or increasing driving stresses, concentration of shear stress, or low resistance to exceed stability thresholds. Particularly soft glacier beds seem to be a common condition among the observed events as they offer smooth contact areas between the glacier and the underlying substrate and are prone to till-strength weakening and eventually basal failure under high pore-water pressure. Partially or fully thawed glacier bed conditions and the presence of liquid water could thus play an important role in the detachments. Surface slopes of the detached glaciers range between around 10∘ and 20∘. This may be low enough to enable the development of thick and thus large-volume glaciers while also being steep enough to allow critical driving stresses to build up. We construct a simple slab model to estimate ranges of glacier slope and width above which a glacier may be able to detach when extensively losing basal resistance. From this model we estimate that all the detachments described in this study occurred due to a basal shear ... |
format |
Article in Journal/Newspaper |
author |
Kääb, Andreas Jacquemart, Mylène Gilbert, Adrien Leinss, Silvan Girod, Luc Huggel, Christian Falaschi, Daniel Ugalde, Felipe Petrakov, Dmitry Chernomorets, Sergey Dokukin, Mikhail Paul, Frank Gascoin, Simon Berthier, Etienne Kargel, Jeffrey S |
author_facet |
Kääb, Andreas Jacquemart, Mylène Gilbert, Adrien Leinss, Silvan Girod, Luc Huggel, Christian Falaschi, Daniel Ugalde, Felipe Petrakov, Dmitry Chernomorets, Sergey Dokukin, Mikhail Paul, Frank Gascoin, Simon Berthier, Etienne Kargel, Jeffrey S |
author_sort |
Kääb, Andreas |
title |
Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
title_short |
Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
title_full |
Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
title_fullStr |
Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
title_full_unstemmed |
Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
title_sort |
sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://www.zora.uzh.ch/id/eprint/211398/ https://www.zora.uzh.ch/id/eprint/211398/1/2021_Paul_tc-15-1751-2021.pdf https://doi.org/10.5167/uzh-211398 https://doi.org/10.5194/tc-15-1751-2021 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
Kääb, Andreas; Jacquemart, Mylène; Gilbert, Adrien; Leinss, Silvan; Girod, Luc; Huggel, Christian; Falaschi, Daniel; Ugalde, Felipe; Petrakov, Dmitry; Chernomorets, Sergey; Dokukin, Mikhail; Paul, Frank; Gascoin, Simon; Berthier, Etienne; Kargel, Jeffrey S (2021). Sudden large-volume detachments of low-angle mountain glaciers – more frequent than thought? The Cryosphere, 15(4):1751-1785. |
op_relation |
https://www.zora.uzh.ch/id/eprint/211398/1/2021_Paul_tc-15-1751-2021.pdf doi:10.5167/uzh-211398 doi:10.5194/tc-15-1751-2021 urn:issn:1994-0416 |
op_rights |
info:eu-repo/semantics/openAccess Creative Commons: Attribution 4.0 International (CC BY 4.0) http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.5167/uzh-21139810.5194/tc-15-1751-2021 |
_version_ |
1802650676182908928 |