HR: 0800h
AN: C21B-0468    [Abstracts]
TI: Spatial Scale for Modelling Blowing Snow on the Canadian Prairieis
AU: * Pomeroy, J W
EM: john.pomeroy@usask.ca
AF: Centre for Hydrology, University of Saskatchewan, 117 Science Place, Saskatoon, SK S7N 5C8, Canada
AU: Fang, X
EM: xif382@mail.usask.ca
AF: Centre for Hydrology, University of Saskatchewan, 117 Science Place, Saskatoon, SK S7N 5C8, Canada
AB: Blowing snow transports and sometimes sublimates much of the seasonal snowfall in the Prairies of western Canada. Snow redistribution is an important feature of Prairie hydrology as deep snowdrifts provide a source of meltwater to replenish ponds and generate streamflow in this dry region. The spatial distribution of snow water equivalent in the spring is therefore of great interest for Prairie hydrology. A test of the appropriate spatial scale for modelling blowing snow redistribution and sublimation was conducted at St Denis National Wildlife Area in the rolling, internally drained prairie pothole region east of Saskatoon, Saskatchewan, Canada. A LiDAR based DEM and LANDSAT based vegetation map were available for this region. A coupled complex windflow and blowing snow model was run with ~250,000 6 m x 6 m grid cells to produce spatially distributed estimates of seasonal blowing snow transport and sublimation. The calculation was then aggregated, using 7 landscape units that represented the major influences of surface roughness, topography and fetch on blowing snow transport and sublimation. Both the distributed and aggregated simulations described similar end of winter snow water equivalent with substantive redistribution of blowing snow from exposed sparsley vegetated sites across topographic drainage divides to the densely vegetated pothole wetlands. Both simulations also agreed well with snow survey observations. While the distributed calculations provide a fascinating and detailed visual image of the interaction of complex landscapes and blowing snow redistribution and sublimation, it is clear that blowing snow transport and sublimation calculations can be successfully aggregated to the spatial scale of the major landscape units in this environment.
DE: 0736 Snow (1827, 1863)
DE: 1805 Computational hydrology
DE: 1818 Evapotranspiration
DE: 1843 Land/atmosphere interactions (1218, 1631, 3322)
DE: 1863 Snow and ice (0736, 0738, 0776, 1827)
SC: Cryosphere [C]
MN: 2007 Fall Meeting