Mapping Ice Flow Velocity of Tidewater Glaciers in Hornsund Fiord Area with the Use of Autonomous Repeat Image Feature Tracking (2018–2022)

Abstract

Dynamic climate changes are particularly apparent in polar regions. Glaciers are retreatng towards the land at a very fast pace. This study demonstrates the application of the feature tracking method in the analysis of ice flow velocity in the region of the Hornsund fiord, southern Spitsbergen, in the years 2018–2022. The calculations were based on the Geogrid and autoRIFT environments and on the Sentinel 1 images. The study also employed external data, such as a numerical terrain model and reference velocity values. The input data, e.g., the chip size and the search limit, were prepared accounting for the specific character of the investigated area. The velocities were calculated for nine biggest glaciers which terminated in the fiord. The accuracy of the results was identified by calculating the median absolute deviation (MAD) of the obtained displacement velocity values from the reference value for areas identified as stable. The study also attempted a causal analysis of the influence of weather factors on the dynamics of ice mass displacement. A systematic year-to-year decrease of the velocity was observed for the entire fiord. In the case of several glaciers, changes related to the ablation season (summer) are also clearly visible. The research results are promising and fill a research gap related to the absence of permanent monitoring and analysis of the dynamics of ice flow in polar regions. It is the first complex and precise study of glacier surface velocity changes, performed on the basis of satellite radar images for the entire Hornsund fiord.

Glacier Surface Velocity Variations in the West Kunlun Mts. with Sentinel-1A Image Feature-Tracking (2014–2023)

“…The successive launches of the Sentinel-1A and Sentinel-1B SAR satellites with 6-12 repeat cycles provided an abundant data source for global glaciers surface velocity assessments, making it possible to monitor short-term variations in glacier flow velocity [16,17]. Milczarek et al [18] used Sentinel-1 to determine the annual velocity changes of tidewater glaciers in the Hornsund Fjord, and analyze the seasonal and transient variations. Yang et al [14] used the time series of Sentinel-1 data to determine the 69 surface velocity fields on the Neche Peninsula, Alaska, and analyze the differences in flow velocity variations among tidewater, lake, and land-terminating glaciers.…”