Abstract:?The Qinghai-Tibet Plateau, also known as the world’s “Third Pole”, is the largest modern glaciation region in the middle and low latitudes of the Northern Hemisphere, which plays an important role in the global climate system. It is of great significance to study the spatiotemporal changes of the glacier velocity for understanding the dynamic characteristics of glaciers and demonstrate the response of glaciers to climate change. Besides, the long-term monitoring of glacier activity on the Qinghai-Tibet Plateau is essential to promote ecological environment protection. Based on the SAR imagery of the Qinghai-Tibet Plateau region acquired by GF-3 from 2019 to 2020 along with an improved pixel-tracking algorithm, the distribution of ice surface motion is obtained. The accurate velocity of the glacier surface (GeoTiff format in 32-bit floating-point) was extracted by precisely removing the global deformation, the topographic-related offset and the effect of the high-frequency noise. And the spatial resolution of the final result is around 12 m by sampling interval of GF-3 with FSI imaging mode. An overall accuracy of about 0.5 m is given by the statistical analysis of the residual movement in the non-glacial region. The results demonstrate that the glacier velocity in the accumulation area is generally faster than that in the terminal or ablation part, some small and medium-sized glaciers have relatively strong activities. Generally, the ice velocity reveals a positive correlation with topography and climate. The dataset could serve as the basis in research of glacial mass balance in Qinghai-Tibet Plateau, providing statistical support to understand the relationship between ice and climate change in High Mountain Asia. Finally, this study could promote the application of domestic remote sensing data in glacier activity and climate change on a deeper level.
Keywords:?Qinghai-Tibet Plateau;?GF-3;;?ice surface motion;? pixel-tracking