Development of Snow Depth and Snow Water Equivalent Algorithm in Western China Using Passive Microwave Remote Sensing Data

Abstract

In order to evaluate the accuracy of snow water equivalent (SWE) inversion algorithm for passive microwave sensor Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) in Western china, we compared SWE obtained from AMSR-E daily SWE product with the ground measurements from 15 meteorological stations in Tibetan plateau in 2003 and 35 meteorological stations in Xinjiang in January 2004. The results show AMSR-E overestimate SWE both in these two regions, and RMSE is 21mm and 31.8 mm in Tibetan plateau and Xinjiang, respectively. Through incorporating snow fraction factor, a new empirical algorithm estimate snow depth and SWE have been developed in Xinjiang. This new algorithm appeared higher accuracy than AMSR-E does in Xinjiang. Due to complex topography, shallow patchy snow and frozen grounds covered at the Tibetan Plateau, this technique didn't show good results. In future we will focus on how to evaluate and eliminate the effects of these factors quantitatively on SWE retrieval.