Possible erosion mechanisms in snow avalanches
Abstract:Snow erosion and entrainment processes in avalanches are classified according to their mechanisms, the flow regimes in which they occur, and their spatial position within the avalanche. Simple, but process-specific, models are proposed for erosion by impacts, abrasion, plowing and blasting. On the basis of order-of-magnitude estimates, the first three mechanisms are clearly expected to be important. The fourth mechanism stipulates that the compaction of the snow cover ahead of the avalanche leads to the flow of escaping air just in front of the avalanche that may disrupt the snow cover and support formation of a saltation layer. The effects of this hypothetical mechanism resemble those of the plowing mechanism. All mechanisms depend strongly on the snow properties, but, with plausible parameter values, erosion rates at or above the experimentally found rates are obtained. The entrainment rate of an avalanche is most often limited by the shear stress needed to accelerate the eroded snow to avalanche speed.
Document Type: Research Article
Publication date: January 1, 2004
- The Annals of Glaciology is a peer-reviewed, thematic journal published 2 to 4 times a year by the International Glaciological Society (IGS). Publication frequency is determined and volume/issue numbers assigned by the IGS Council on a year-to-year basis and with a lead time of 3 to 4 years. The Annals of Glaciology is included in the ISI Science Citation Index from volume 50, number 50 onwards.
Themes can be on any aspect of the study of snow and ice. Individual members can make a suggestion for a theme for an Annals issue to the Secretary General, who will forward it to the IGS Publications Committee. The IGS Publication Committee will make a recommendation for an individual themed Annals issue, together with a potential Annals Chief Editor for that issue, to IGS Council. The IGS Council will make the decision whether to proceed, taking into account the spread of topics and the overall capacity for publication of pages in Annals.
- Editorial Board
- Information for Authors
- Ingenta Connect is not responsible for the content or availability of external websites