A study of the size of snow particles in powder snow avalanches

In this work, we study the size of the particles involved in a powder snow avalanche phenomenon. To determine these sizes, we study all the phenomena the particles have to face before arriving in the “body” of the avalanche. We study the boundary layer which is at the bottom of the avalanche. We determine, with the help of experimental data, the range of size of the particles that can be entrained by the avalanche. We then examine the possibility for these particles to reach the top of the boundary layer, and so to take part in the avalanche. Our final result is that the more frequent particles suspended in a powder snow avalanche have a size lower than 200 micrometers.