气候变化领域集成服务门户(CCPortal): Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK

CCPortal

DOI	10.5194/tc-13-3353-2019
	Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK
	Richter B.; Schweizer J.; Rotach M.W.; Van Herwijnen A.
发表日期	2019
ISSN	19940416
EISSN	13
起始页码	3353
结束页码	3366
卷号	13 期号:12
英文摘要	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. © 2019 IEEE Computer Society. All rights reserved.
学科领域	crack propagation; parameterization; shear modulus; snow avalanche; snowpack; stratigraphy; vertical profile; weather station; Davos; Graubunden; Switzerland
语种	英语
scopus关键词	crack propagation; parameterization; shear modulus; snow avalanche; snowpack; stratigraphy; vertical profile; weather station; Davos; Graubunden; Switzerland
来源期刊	The Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/118793
作者单位	WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland; Institute for Atmospheric and Cryospheric Sciences, University of Innsbruck, Innsbruck, Austria
推荐引用方式 GB/T 7714	Richter B.,Schweizer J.,Rotach M.W.,et al. Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK[J],2019,13(12).
APA	Richter B.,Schweizer J.,Rotach M.W.,&Van Herwijnen A..(2019).Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK.The Cryosphere,13(12).
MLA	Richter B.,et al."Validating modeled critical crack length for crack propagation in the snow cover model SNOWPACK".The Cryosphere 13.12(2019).