Retrieving Snow Depth Information From AMSR2 Data for Qinghai–Tibet Plateau

Passive microwave data have been extensively used for snow depth (SD) inversion, but their accuracy has large error in the Qinghai-Tibet Plateau (QTP). Thus, there is still room for improvement in regional SD inversion. Ground-measured SD data combined with elevation, longitude, and land cover data were used to develop a multifactor SD inversion model based on Advanced Microwave Scanning Radiometer 2 (AMSR2) over the QTP. The SD inversion model and the AMSR2 SD product were validated and compared using the meteorological stations and ground-measured SD over the QTP at the same time. The results show that the root-mean-square error (RMSE) of the novel model developed in this study is approximately 5 cm, which is much better than the accuracy of the AMSR2 SD product (11-13 cm) released by the Japan Aerospace Exploration Agency. When the ground-measured SD is less than 30 cm, the RMSE and the mean absolute error of the developed model are below 7 and 6 cm, respectively, and the BIAS is approximately 1 cm. The SD inversion results are poor in the western part of the plateau due to the complex terrain and thick snow cover, and its RMSE is greater than 15 cm. In conclusion, this novel SD inversion model is more applicable and accurate than the AMSR2 SD products.