Snow accumulation

Snow accumulation and loss is controlled primarily by atmospheric conditions and the elevation and slope of the terrain [8]. Atmospheric processes of interest are precipitation, deposition, condensation, turbulent transfer of heat and moisture, radiative exchange and air movement. Land features influence snow accumulation by slope, orientation, and by shadowing properties. These factors act together and are related to each other [2]. For example, mountain ranges interrupt the winds that can redistribute the snow into drifts, slope and aspect influence incoming solar radiation and humidity, and latitude and elevation control air and ground temperature.

The variability of snow cover is commonly considered on three geometric scales [8]:

• Regional scale: large areas with linear distances up to 1000km in which dynamic meteorological effects such as wind flow around barriers and lake effects are important
• Local scale: areas with linear distances of 100m to 1000m in which accumulation may be related to the elevation, aspect and slope of the terrain and to the canopy and crop density, tree species, height and extent of the vegetative cover
• Microscale: distances of 10m to 100m over which accumulation patterns result primarily due to surface roughness

For our simulations, we consider only local scale and microscale.