Influence of slab depth spatial variability on skier-triggering probability and avalanche size

Meloche, Francis ORCID: https://orcid.org/0009-0001-5884-5597, Guillet, Louis, Gauthier, Francis, Langlois, Alexandre et Gaume, Johan (2024). Influence of slab depth spatial variability on skier-triggering probability and avalanche size. Annals of glaciology . pp. 1-15.

Prévisualisation

PDF Licence d'utilisation : CC BY 4.0. Télécharger (1MB) | Prévisualisation

Résumé

Spatial variability of snowpack properties adds uncertainty in the evaluation of avalanche hazard. We propose a combined mechanical–statistical approach to study how spatial variation of slab depth affects the skier-triggering probability and possible release size. First, we generate multiple slab depth maps on a plane fictional slope based on Gaussian Random Fields (GRF) for a specific set of mean, variance and correlation length. For each GRF, we derive analytically the Skier Propagation Index (SPI). We then simulate multiple skier tracks and computed the probability based on the number of skier hits where SPI is below 1. Finally, we use a depth-averaged material point method to evaluate the possible avalanche size for given slab depth variations. The results of this analysis show that large correlation lengths and small variances lead to a lower probability of skier-triggering as it reduces the size and the number of areas with low slab depth. Then, we show the effect of skiing style and skier group size on skier-triggering probability. Spatial variability also affects the possible avalanche size by adding stress fluctuation causing early or late tensile failure. Finally, we demonstrate with our models the well-known relationship between the probability and the size in avalanche forecasting.

Type de document :	Article
Validation par les pairs :	Oui
Mots-clés :	Avalanches ; Neige ; Mécanique de la neige / Avalanches ; Snow ; Snow mechanics.
Version du document déposé :	Version officielle de l'éditeur
Départements et unités départementales :	Département de biologie, chimie et géographie
Déposé par :	DIUQAR UQAR
Date de dépôt :	31 oct. 2024 18:13
Dernière modification :	31 oct. 2024 18:13
URI :	https://semaphore.uqar.ca/id/eprint/3088

Actions (administrateurs uniquement)

Éditer la notice