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Large amounts of snow on the earth play an important role in atmospheric circulation and radiant energy budget in earth-atmosphere system. The spatial and temporal distribution of snow and the snow albedo determine the calculation of radiation energy budget. MODIS product provides snow cover data and Discrete Ordinate Radiative Transfer method can calculate snow albedo at ultraviolet, visible, infrared wavelengths. The monthly average snow cover ratio of grid cells in MOD10CM data sets from 2004 to 2018 was analyzed. The results show that the areas in which there are more months with snow in winter are high latitudes that include the arctic. The areas in which there are more months with snow in summer are Greenland and southern South America. The months with snow cover are positively correlated with the average snow cover ratio. DISORT model simulated the snow albedo under different radii, different snow thicknesses and different impurity concentrations. The larger the snow grain size, the lower the snow albedo and the lower the infinite depth of snow. Impurities in snow can reduce snow albedo and infinite depth of snow thickness. When the dust is 100ppmv in snow, the snow albedo with a radius of 50μm and 1000μm decreases by 10% and 40%, respectively, compared with albedo of pure snow. The spatial and temporal distribution of snow in a particular region and the albedo simulation of snow are helpful for the calculation of the radiation energy budget in this region and investigating the association between them in further study.
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