Analysis of the passive microwave high-frequency signal in the shallow snow retrieval

Over the western China, due to the influence from shallow snow, the passive microwave remote sensing algorithm show its imbecility when using the gradient brightness temperature (Tb) algorithm of 36.5Ghz-18.7Ghz. In this paper, we employee several ground time-series snow depth dataset and the corresponding satellite brightness temperature to evaluate the 36.5Ghz/l 8.7Ghz and high frequencies´ (85Ghz or 89.0Ghz/18.7Ghz) ability for the shallow snow retrieval. From the analysis, we can get that the high frequencies has its potential for the shallow, which is suit for the snow situation over the high land, even with the atmosphere influence at high frequency. The result tell that the relative deep snow (>; 20cm) the Tbs at 36-18GHz are more reliable than that of high frequency, while over the shallow snow especially <;20cm), the pair 36-18 is insensitive, but the high frequency pair (89/85-18GHz) shows its obvious possibility.