Seasonal ice flow velocity variations of Polar Record Glacier, East Antarctica during 2016-2019 using Sentinel-1 data

Remote sensing-based investigation of ice flow dynamics of Polar Record Glacier (PRG) during December-April of 2016-2019 has been conducted in this work. Using offset tracking method on the Sentinel-1 Synthetic Aperture Radar (SAR) images, we estimated the glacier ice flow velocity. Ice flow velocity near the glacier terminus indicated higher velocity during January and subsequently showed lower values in December during 2016-2019. The maximum and minimum velocity of the glacier was found to be similar to 2.54 and 0.03 m/d for 2016-2017, similar to 2.49 and 0.03 m/d for 2017-2018, and similar to 2.47 and 0.03 m/d for 2018-2019. Results indicate that the maximum velocity occurred at the terminus of the glacier and minimum flow was detected on the ice sheet portion of the glacier. The average ice front position receded from similar to 900 m in 2016-2017 to similar to 650 m in 2017-2018 to similar to 200 m in 2018-2019. A slowdown near the glacier terminus is observed for the period 2018-2019, while the total glacier advancement was observed to be 28 km(2) from 877 km(2) to 905 km(2 )during the period of 2016-2019. The enhanced velocity at the terminus in the early winter (March and April) was attributed to ice-free water surrounding the PRG terminus which eliminated the buttressing effect.

Automated summary

This study investigated the ice flow dynamics of the Polar Record Glacier from December to April between 2016 and 2019 using remote sensing techniques. The results showed fluctuating ice flow velocities, with higher speeds near the glacier terminus and lower values towards the ice sheet portion. The study also observed changes in the glacier's front position and total area, attributing the increased speed in early winter to ice-free water surrounding the glacier terminus.