Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK
Observed snow stratigraphy and snow stability are of key importance for avalanche forecasting. Such observations are rare and snow cover models can improve the spatial and temporal resolution. To evaluate snow stability, failure initiation and crack propagation have to be considered. Recently, a new...
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ftdoajarticles:oai:doaj.org/article:f33d9c17a86b4c088f61f6db4d30b447 2023-05-15T18:32:26+02:00 Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK B. Richter J. Schweizer M. W. Rotach A. van Herwijnen 2019-12-01T00:00:00Z https://doi.org/10.5194/tc-13-3353-2019 https://doaj.org/article/f33d9c17a86b4c088f61f6db4d30b447 EN eng Copernicus Publications https://www.the-cryosphere.net/13/3353/2019/tc-13-3353-2019.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-13-3353-2019 1994-0416 1994-0424 https://doaj.org/article/f33d9c17a86b4c088f61f6db4d30b447 The Cryosphere, Vol 13, Pp 3353-3366 (2019) Environmental sciences GE1-350 Geology QE1-996.5 article 2019 ftdoajarticles https://doi.org/10.5194/tc-13-3353-2019 2022-12-31T09:28:44Z Observed snow stratigraphy and snow stability are of key importance for avalanche forecasting. Such observations are rare and snow cover models can improve the spatial and temporal resolution. To evaluate snow stability, failure initiation and crack propagation have to be considered. Recently, a new stability criterion relating to crack propagation, namely the critical crack length, was implemented into the snow cover model SNOWPACK. The critical crack length can also be measured in the field with a propagation saw test, which allows for an unambiguous comparison. To validate and improve the parameterization for the critical crack length, we used data from 3 years of field experiments performed close to two automatic weather stations above Davos, Switzerland. We monitored seven distinct weak layers and performed in total 157 propagation saw tests on a weekly basis. Comparing modeled to measured critical crack length showed some discrepancies stemming from model assumption. Hence, we replaced two variables of the original parameterization, namely the weak layer shear modulus and thickness, with a fit factor depending on weak layer density and grain size. With these adjustments, the normalized root-mean-square error between modeled and observed critical crack lengths decreased from 1.80 to 0.28. As the improved parameterization accounts for grain size, values of critical crack lengths for snow layers consisting of small grains, which in general are not weak layers, become larger. In turn, critical weak layers appear more prominently in the vertical profile of critical crack length simulated with SNOWPACK. Hence, minimal values in modeled critical crack length better match observed weak layers. The improved parameterization of critical crack length may be useful for both weak layer detection in simulated snow stratigraphy and also providing more realistic snow stability information – and hence may improve avalanche forecasting. Article in Journal/Newspaper The Cryosphere Directory of Open Access Journals: DOAJ Articles The Cryosphere 13 12 3353 3366 |
institution |
Open Polar |
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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. Richter J. Schweizer M. W. Rotach A. van Herwijnen Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Observed snow stratigraphy and snow stability are of key importance for avalanche forecasting. Such observations are rare and snow cover models can improve the spatial and temporal resolution. To evaluate snow stability, failure initiation and crack propagation have to be considered. Recently, a new stability criterion relating to crack propagation, namely the critical crack length, was implemented into the snow cover model SNOWPACK. The critical crack length can also be measured in the field with a propagation saw test, which allows for an unambiguous comparison. To validate and improve the parameterization for the critical crack length, we used data from 3 years of field experiments performed close to two automatic weather stations above Davos, Switzerland. We monitored seven distinct weak layers and performed in total 157 propagation saw tests on a weekly basis. Comparing modeled to measured critical crack length showed some discrepancies stemming from model assumption. Hence, we replaced two variables of the original parameterization, namely the weak layer shear modulus and thickness, with a fit factor depending on weak layer density and grain size. With these adjustments, the normalized root-mean-square error between modeled and observed critical crack lengths decreased from 1.80 to 0.28. As the improved parameterization accounts for grain size, values of critical crack lengths for snow layers consisting of small grains, which in general are not weak layers, become larger. In turn, critical weak layers appear more prominently in the vertical profile of critical crack length simulated with SNOWPACK. Hence, minimal values in modeled critical crack length better match observed weak layers. The improved parameterization of critical crack length may be useful for both weak layer detection in simulated snow stratigraphy and also providing more realistic snow stability information – and hence may improve avalanche forecasting. |
format |
Article in Journal/Newspaper |
author |
B. Richter J. Schweizer M. W. Rotach A. van Herwijnen |
author_facet |
B. Richter J. Schweizer M. W. Rotach A. van Herwijnen |
author_sort |
B. Richter |
title |
Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
title_short |
Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
title_full |
Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
title_fullStr |
Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
title_full_unstemmed |
Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK |
title_sort |
validating modeled critical crack length for crack propagation in the snow cover model snowpack |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-3353-2019 https://doaj.org/article/f33d9c17a86b4c088f61f6db4d30b447 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, Vol 13, Pp 3353-3366 (2019) |
op_relation |
https://www.the-cryosphere.net/13/3353/2019/tc-13-3353-2019.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-13-3353-2019 1994-0416 1994-0424 https://doaj.org/article/f33d9c17a86b4c088f61f6db4d30b447 |
op_doi |
https://doi.org/10.5194/tc-13-3353-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
12 |
container_start_page |
3353 |
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3366 |
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