Dependence of ground snow loads on elevation in western Canada

Provincial and territorial snow course measurements and the Atmospheric Environment Service (AES) snow depth measurements were combined and analyzed using Geographical Information System (GIS) software to study the spatial variation of design Ground Snow Loads in mountainous areas of western Canada. With careful attention to mesoscale climate processes, physical models were developed that described the regional variation of snow loads with elevation dependency for regions of homogeneous snow climatology. Valley and mountain range specific regression relations were derived that were used to normalize return period snow observations with respect to critical or reference elevations. Interpolation procedures were applied to determine site specific or grid point snow loads. Further work is needed to better quantify uncertainties associated with the snow fields and snow data. The results of the study provided an improved methodology for determining Ground Snow Load recommendations supporting the National Building Code of Canada in mountainous areas.