A process-based approach to estimate point snow instability
Snow instability data provide information about the mechanical state of the snow cover and are essential for forecasting snow avalanches. So far, direct observations of instability (recent avalanches, shooting cracks or whumpf sounds) are complemented with field tests such as the rutschblock test, s...
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ftdoajarticles:oai:doaj.org/article:b8a724abaf4c46008cf9adddb258adc6 2023-05-15T18:32:31+02:00 A process-based approach to estimate point snow instability B. Reuter J. Schweizer A. van Herwijnen 2015-05-01T00:00:00Z https://doi.org/10.5194/tc-9-837-2015 https://doaj.org/article/b8a724abaf4c46008cf9adddb258adc6 EN eng Copernicus Publications http://www.the-cryosphere.net/9/837/2015/tc-9-837-2015.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-9-837-2015 https://doaj.org/article/b8a724abaf4c46008cf9adddb258adc6 The Cryosphere, Vol 9, Iss 3, Pp 837-847 (2015) Environmental sciences GE1-350 Geology QE1-996.5 article 2015 ftdoajarticles https://doi.org/10.5194/tc-9-837-2015 2022-12-31T01:11:47Z Snow instability data provide information about the mechanical state of the snow cover and are essential for forecasting snow avalanches. So far, direct observations of instability (recent avalanches, shooting cracks or whumpf sounds) are complemented with field tests such as the rutschblock test, since no measurement method for instability exists. We propose a new approach based on snow mechanical properties derived from the snow micro-penetrometer that takes into account the two essential processes during dry-snow avalanche release: failure initiation and crack propagation. To estimate the propensity of failure initiation we define a stress-based failure criterion, whereas the propensity of crack propagation is described by the critical cut length as obtained with a propagation saw test. The input parameters include layer thickness, snow density, effective elastic modulus, strength and specific fracture energy of the weak layer – all derived from the penetration-force signal acquired with the snow micro-penetrometer. Both instability measures were validated with independent field data and correlated well with results from field tests. Comparisons with observed signs of instability clearly indicated that a snowpack is only prone to avalanche if the two separate conditions for failure initiation and crack propagation are fulfilled. To our knowledge, this is the first time that an objective method for estimating snow instability has been proposed. The approach can either be used directly based on field measurements with the snow micro-penetrometer, or be implemented in numerical snow cover models. With an objective measure of instability at hand, the problem of spatial variations of instability and its causes can now be tackled. Article in Journal/Newspaper The Cryosphere Directory of Open Access Journals: DOAJ Articles The Cryosphere 9 3 837 847 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 B. Reuter J. Schweizer A. van Herwijnen A process-based approach to estimate point snow instability |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Snow instability data provide information about the mechanical state of the snow cover and are essential for forecasting snow avalanches. So far, direct observations of instability (recent avalanches, shooting cracks or whumpf sounds) are complemented with field tests such as the rutschblock test, since no measurement method for instability exists. We propose a new approach based on snow mechanical properties derived from the snow micro-penetrometer that takes into account the two essential processes during dry-snow avalanche release: failure initiation and crack propagation. To estimate the propensity of failure initiation we define a stress-based failure criterion, whereas the propensity of crack propagation is described by the critical cut length as obtained with a propagation saw test. The input parameters include layer thickness, snow density, effective elastic modulus, strength and specific fracture energy of the weak layer – all derived from the penetration-force signal acquired with the snow micro-penetrometer. Both instability measures were validated with independent field data and correlated well with results from field tests. Comparisons with observed signs of instability clearly indicated that a snowpack is only prone to avalanche if the two separate conditions for failure initiation and crack propagation are fulfilled. To our knowledge, this is the first time that an objective method for estimating snow instability has been proposed. The approach can either be used directly based on field measurements with the snow micro-penetrometer, or be implemented in numerical snow cover models. With an objective measure of instability at hand, the problem of spatial variations of instability and its causes can now be tackled. |
format |
Article in Journal/Newspaper |
author |
B. Reuter J. Schweizer A. van Herwijnen |
author_facet |
B. Reuter J. Schweizer A. van Herwijnen |
author_sort |
B. Reuter |
title |
A process-based approach to estimate point snow instability |
title_short |
A process-based approach to estimate point snow instability |
title_full |
A process-based approach to estimate point snow instability |
title_fullStr |
A process-based approach to estimate point snow instability |
title_full_unstemmed |
A process-based approach to estimate point snow instability |
title_sort |
process-based approach to estimate point snow instability |
publisher |
Copernicus Publications |
publishDate |
2015 |
url |
https://doi.org/10.5194/tc-9-837-2015 https://doaj.org/article/b8a724abaf4c46008cf9adddb258adc6 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, Vol 9, Iss 3, Pp 837-847 (2015) |
op_relation |
http://www.the-cryosphere.net/9/837/2015/tc-9-837-2015.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-9-837-2015 https://doaj.org/article/b8a724abaf4c46008cf9adddb258adc6 |
op_doi |
https://doi.org/10.5194/tc-9-837-2015 |
container_title |
The Cryosphere |
container_volume |
9 |
container_issue |
3 |
container_start_page |
837 |
op_container_end_page |
847 |
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1766216629275852800 |