Numerical simulations of snow saltation over flat terrain: Development of snow transport

Snow transport would develop downwind from its starting point until it reaches the saturated state. This study proposes an Eulerian-Lagrangian snow saltation model to simulate the development of snow transport over flat terrain. The reliability of the numerical model is validated using the published experimental data. The simulated results of the modified wind profile, mass flux profile and snow transport rate are in good agreement with the experimental data. Based on the simulated results, the development characteristics of snow concentration and snow transport rate along fetch are discussed. Snow concentration first increases rapidly along fetch; it then slows down and finally reaches the equilibrium. Correspondingly, the snow transport rate first increases rapidly and reaches 0.84 of the saturated value at a distance of around 20 m, and then it slows down and reaches the saturated value at a distance of around 60 m. For different wind velocities, the saturated snow transport rate is linearly related to the fifth power of friction velocity. The simulated surface flux is cross-checked with that calculated by the previous erosion model, and the results agree well under the condition of low wind velocity.