Abstract
A simple diagnostic model was used to derive afternoon (0000 UTC) mixing-layer depths from gridded zero hour output from the Canadian Global Environmental Multiscale (GEM) numerical weather model interpolated to approximately 200 locations in the Prairie provinces of Canada. Knowledge of the spatial pattern of monthly mean afternoon mixing-layer depths was enhanced by associating the annual cycles of monthly means with eco-climatic regions - regions with fairly uniform terrain and soils, and where similar vegetation indicate that the area experiences, on average, similar synoptic-scale weather and produces similar surface fluxes of heat and moisture. When the mixing-layer depth is used to assess the dilution of airborne pollutants or to determine the specific humidity of the boundary layer, the eco-climatic region rather than proximity to the location-of-interest should be the primary factor in the selection of an appropriate radiosonde site.
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Raddatz, R., Noonan, M. Monthly mean afternoon mixing-layer depths “tuned” to the eco-climatic regions of the Canadian Prairie provinces. Environ Model Assess 9, 147–158 (2005). https://doi.org/10.1007/s10666-005-3802-x
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DOI: https://doi.org/10.1007/s10666-005-3802-x