| Summary: | Prepared for John Kort and Gary Bank, Agriculture and Agri-Food Canada. Snowcover accumulation has tremendous impacts on Canadian Prairie hydrology and agriculture (Pomeroy and Gray, 1995; Fang and Pomeroy, 2007). Wind redistribution of snow or blowing snow is frequent in the Prairies and controls the accumulation of snowcover. Blowing snow transport is normally accompanied by in-transit sublimation (Dyunin, 1959; Schmidt, 1972; Pomeroy, 1989). Blowing snow transport and sublimation result in losses to exposed snowcovers from erosion of from 30% to 75% of annual snowfall in prairie and steppe environments (Tabler, 1975; Pomeroy et al., 1993). The disposition of this eroded snow to either sublimation or transport and subsequent deposition is important to surface water budgets. Transported snow is available for snowmelt, while that sublimated is returned to the atmosphere. Blowing snow fetch, or the downwind distance of uniform terrain that permits snow transport, determines the disposition between sublimation and transport, longer fetches promoting greater sublimation per unit area (Tabler, 1975; Pomeroy and Gray, 1995). Calculation of blowing snow fluxes (erosion, transport, sublimation) for a uniform area, using the presumption of horizontal steady state flow (Pomeroy, 1989), does not provide sufficient information to calculate the snow cover mass balance over larger areas where flow at many points in the landscape will deviate significantly from steady state conditions. A comprehensive model of blowing snow was assembled by Pomeroy and Li (2000) and tested extensively in the Prairie and Arctic environments where it was shown to accurately predict snow accumulation. Subsequent tests by Fang and Pomeroy (2009) show that the model can accurately predict snow accumulation in a wide range of prairie to partly wooded environments. This project compares field measurements of snow distribution, associated with shelterbelts at various spacings, to modeled results of snow redistribution by wind. Virtual shelterbelt ...
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