Abstract

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 ∼2.54 and 0.03 m/d for 2016–2017, ∼2.49 and 0.03 m/d for 2017–2018, and ∼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 ∼900 m in 2016–2017 to ∼650 m in 2017–2018 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 km² from 877 km² to 905 km² 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.

摘要

在这项工作中，对 2016 年 12 月至 2019 年 4 月期间极地记录冰川（PRG）的冰流动力学进行了基于遥感的调查。使用 Sentinel-1 合成孔径雷达 (SAR) 图像上的偏移跟踪方法，我们估计了冰川冰的流速。冰川终点附近的冰流速度表明 1 月份的速度较高，随后在 2016-2019 年 12 月份的速度较低。发现冰川的最大和最小速度为 2016-2017 年的 ~2.54 和 0.03 m/d，2017-2018 年的 ~2.49 和 0.03 m/d，以及 2018-2019 年的 ~2.47 和 0.03 m/d。结果表明，最大速度出现在冰川的终点，最小的流量出现在冰川的冰盖部分。平均冰锋位置从 2016-2017 年的 ~900 m 下降到 2017-2018 年的 ~650 m 到 2018-2019 年的 ~200 m。在 2018 年至 2019 年期间观察到冰川终点附近的减速，而冰川总推进量为 28 公里²在 2016-2019 年期间从 877 km ²增加到 905 km ^{2 。}初冬（3 月和 4 月）终点处的速度提高归因于 PRG 终点周围的无冰水消除了支撑效应。