Possible erosion mechanisms in snow avalanches
Snow erosion and entrainment processes in avalanches are classified according to their mechanisms, the flow regimes in which they occur, and their spatial position within the avalanche. Simple, but process-specific, models are proposed for erosion by impacts, abrasion, plowing and blasting. On the b...
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Cambridge University Press
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Online Access: | https://hdl.handle.net/11250/3098802 https://doi.org/10.3189/172756404781815068 |
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ftngi:oai:ngi.brage.unit.no:11250/3098802 2023-11-12T04:01:18+01:00 Possible erosion mechanisms in snow avalanches Gauer, Peter Issler, Dieter 2004 application/pdf https://hdl.handle.net/11250/3098802 https://doi.org/10.3189/172756404781815068 eng eng Cambridge University Press urn:issn:0260-3055 https://hdl.handle.net/11250/3098802 https://doi.org/10.3189/172756404781815068 The Author(s) 384-394 38 Annals of Glaciology Avalanche-RnD Snøskred-FoU Journal article 2004 ftngi https://doi.org/10.3189/172756404781815068 2023-11-01T23:48:58Z Snow erosion and entrainment processes in avalanches are classified according to their mechanisms, the flow regimes in which they occur, and their spatial position within the avalanche. Simple, but process-specific, models are proposed for erosion by impacts, abrasion, plowing and blasting. On the basis of order-of-magnitude estimates, the first three mechanisms are clearly expected to be important. The fourth mechanism stipulates that the compaction of the snow cover ahead of the avalanche leads to the flow of escaping air just in front of the avalanche that may disrupt the snow cover and support formation of a saltation layer. The effects of this hypothetical mechanism resemble those of the plowing mechanism. All mechanisms depend strongly on the snow properties, but, with plausible parameter values, erosion rates at or above the experimentally found rates are obtained. The entrainment rate of an avalanche is most often limited by the shear stress needed to accelerate the eroded snow to avalanche speed. Article in Journal/Newspaper Annals of Glaciology Norwegian Geotechnical Institute (NGI) Digital Archive Annals of Glaciology 38 384 392 |
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Open Polar |
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Norwegian Geotechnical Institute (NGI) Digital Archive |
op_collection_id |
ftngi |
language |
English |
topic |
Avalanche-RnD Snøskred-FoU |
spellingShingle |
Avalanche-RnD Snøskred-FoU Gauer, Peter Issler, Dieter Possible erosion mechanisms in snow avalanches |
topic_facet |
Avalanche-RnD Snøskred-FoU |
description |
Snow erosion and entrainment processes in avalanches are classified according to their mechanisms, the flow regimes in which they occur, and their spatial position within the avalanche. Simple, but process-specific, models are proposed for erosion by impacts, abrasion, plowing and blasting. On the basis of order-of-magnitude estimates, the first three mechanisms are clearly expected to be important. The fourth mechanism stipulates that the compaction of the snow cover ahead of the avalanche leads to the flow of escaping air just in front of the avalanche that may disrupt the snow cover and support formation of a saltation layer. The effects of this hypothetical mechanism resemble those of the plowing mechanism. All mechanisms depend strongly on the snow properties, but, with plausible parameter values, erosion rates at or above the experimentally found rates are obtained. The entrainment rate of an avalanche is most often limited by the shear stress needed to accelerate the eroded snow to avalanche speed. |
format |
Article in Journal/Newspaper |
author |
Gauer, Peter Issler, Dieter |
author_facet |
Gauer, Peter Issler, Dieter |
author_sort |
Gauer, Peter |
title |
Possible erosion mechanisms in snow avalanches |
title_short |
Possible erosion mechanisms in snow avalanches |
title_full |
Possible erosion mechanisms in snow avalanches |
title_fullStr |
Possible erosion mechanisms in snow avalanches |
title_full_unstemmed |
Possible erosion mechanisms in snow avalanches |
title_sort |
possible erosion mechanisms in snow avalanches |
publisher |
Cambridge University Press |
publishDate |
2004 |
url |
https://hdl.handle.net/11250/3098802 https://doi.org/10.3189/172756404781815068 |
genre |
Annals of Glaciology |
genre_facet |
Annals of Glaciology |
op_source |
384-394 38 Annals of Glaciology |
op_relation |
urn:issn:0260-3055 https://hdl.handle.net/11250/3098802 https://doi.org/10.3189/172756404781815068 |
op_rights |
The Author(s) |
op_doi |
https://doi.org/10.3189/172756404781815068 |
container_title |
Annals of Glaciology |
container_volume |
38 |
container_start_page |
384 |
op_container_end_page |
392 |
_version_ |
1782332266265968640 |