Three-dimensional movement inversion of Shisha Pangma glacier using Sentinel-1 and Landsat8 images

SAR offset and optical offset are important techniques for glacier movement monitoring, but there are few researches on 3D deformation by integrating images from different platforms. In this paper, large glaciers in The Shisha Pangma area of Nyalam County, Tibet from November 2019 to January 2021 were selected as the research area. Based on variance component estimation, Sentinel-1 and Landsat8 data of the study area were combined for three-dimensional glacier calculation. Optical images of the same period were selected for comparative analysis of the offset estimation results. At the same time, the accuracy of the method was evaluated by selecting the stable area, and the applicability and accuracy of the method in glacier movement monitoring were analyzed. The results show that the maximum velocity of the glacier is 21 cm/day in the east-west direction, 68 cm/day in the north-south direction, and 17 cm/day in the vertical direction. Compared with the glacier displacement results obtained from a single image, the multi-image joint algorithm can compensate for the incoherence of SAR data and the low quality pixel values of optical data, and obtain more complete and detailed glacier information and higher accuracy of monitoring results. This paper can provide reference and technical support for using data from different platforms to jointly monitor multi-dimensional and high-precision changes of mountain glaciers.