THEORETICAL STUDY ON IMPACTS OF SOME LAND SURFACE ELEMENTS HETEROGENEITIES UPON MODEL OUTPUT

By means of averaged parameterization, a theoretical study is concerned with influences of the heterogeneous distributions of surface temperature, roughness, snow depth and density on their calculated physical quantities.Results indicate that with the surface temperature heterogeneity taken into account, gridded averaged long w ave radiation flux is increased and so is the saturation vapor pressure at surface, which is mo re sensitive to the temperature inhomogeneity compared to the radiation flux for the same coefficient of variation in the temperature distribution and constant temperature condition ;the heterogeneity of surface roughness exert s some impacts on neutral drag coefficient and BATS snow coverage and so does the inhomogeneity of snow depth and density on snow coverage .Key