High‐Resolution Large Eddy Simulation of Snow Accumulation in Alpine Terrain

摘要: Snow accumulation in alpine terrain is controlled by three main processes that act at different spatial scales: (i) orographic snowfall (ii) preferential deposition of and (iii) wind-induced snow transport deposited snow. The relative importance these largely remains uncertain small scale (10-100 m). This study presents how high-resolution coupled snowpack/atmosphere simulations help quantifying the effects processes. simulation system consists detailed snowpack model Crocus atmospheric Meso-NH used Large Eddy Simulation (LES) mode. Dedicated routines allow to explicitly simulate transport. Our case a event occurred February 2011 French Alps. Three nested domains 450-, 150- 50-m grid spacing complex 3D precipitation wind fields down fine scale. We firstly assess ability reproduce meteorological conditions during (wind speed direction, amount blowing fluxes). variability then considered. At spacing, local maxima associated with formation rimed aggregates graupel regions sustained updrafts. Variograms show resultant lower than when considering Despite an overestimation simulated fluxes, our results suggest source study.