Motion Characteristics of the South Inilchek Glacier Derived from New C-Band SAR Satellite

This study present the results of measuring the motion characteristics of the South Inilchek glacier with the C-band Sentinel-1 images acquired from February 2015 to February. 2017. During the offsets estimation in offset-tracking method, we firstly adopt three-step method to achieve high precision overall registration, and then change the matched window size to estimate the local offset with the NCC(normalized cross correlation) algorithm, which was further separated to get glacier motion information. The observation results show that the significant high-speed flow area was the ice tongue, where the flow velocity reduced from the upper to the bottom and slowed obviously at the end, and increased from its both sides to the middle. Moreover, the glacier motion velocity had the same trend with the temperature variation seasonally. The glacier tongue moved with the maximum average velocity of 49 cm/d during the period of May to August, and with the slowest moving in the interval from November to February for about 25-30 cm/d. While in terms of annual changes the velocity in the summer of 2015 was higher than that in 2016 as a whole for about 1-3 cm/d, and there was no marked difference in the other seasons. Furthermore, the monitoring result was demonstrated by comparing the results from Sentinel-1 images in quantity with that from high resolution L-band PALSAR-2 images. The statistics of the sparse pixels in the tongue indicated that the average of the velocity difference was 3.48 cm/d and the standard deviation was ±3.78 cm/d, which confirmed the reliability of the results.