Effect of Grain Size and Snowpack Water Equivalence onVisible and NearInfrared Satellite Observations of Snow
نویسنده
چکیده
Satellite observations of snow in the near-infrared wavelengths can be used to roughly estimate snow grain size. When the grain size is large, it is possible to use measurements in the visible wavelengths to estimate snow water equivalence below some threshold value of around 100 mm. While sufficient data to fully evaluate these possibilities are not available, model calculations, selected satellite observations, and limited ground truth are in qualitative agreement. Complications arise because the effect of contamination by atmospheric aerosols is similar to that of finite depth, and because the near-infrared channel on the NOAA TIROS-N series satellites is not in the wavelength region where snow reflectance is most sensitive to grain size.
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