The Location and Timing of Deep Slab Avalanches

• Published in: Journal of Glaciology
• Main Author: Bradley, Charles C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1970
• Subjects: Earth-Surface Processes; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s002214300002356x; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S002214300002356X

Winter observations in the northern Rocky Mountains of Montana show two periods during which one may expect a collapsing snowpack and accompanying avalanches: (1) shaded and sheltered areas: December-February; (2) sunny and exposed areas: March-May. These periods appear to be linked in part to the cyclic rise and fall of strength in the basal snow layer. It is suggested that sheltered slopes are often about a half-cycle ahead of sunny slopes because sheltered slopes tend to retain the early snows which later become the critically weak basal layer on these slopes.