Dataset for: Fast retreat of Pope, Smith, and Kohler glaciers in West Antarctica observed by satellite interferometry

Pope, Smith, and Kohler glaciers, in the Amundsen Sea Embayment of West Antarctica, have experienced enhanced ocean-induced ice-shelf melt, glacier acceleration, ice thinning, and grounding line retreat in the past thirty years, in a glaciological setting with retrograde bedrock slopes conducive to marine ice sheet instability. Here we present observations of the grounding line retreat of these glaciers since 2014 using a constellation of interferometric radar satellites with a short revisit cycle combined with precision surface elevation data. We find that the glacier grounding lines develop spatially-variable, km-sized, tidally-induced migration zones. After correction for tidal effects, we detect a sustained pattern of retreat coincident with high melt rates of un-grounded ice, marked by episodes of more rapid retreat. In 2017, Pope Glacier retreated 3.5 km in 3.6 months, or 11.7 km/yr. In 2016-2018, Smith West retreated at 2 km/yr and Kohler at 1.3 km/yr. While the retreat slowed down in 2018-2020, these retreat rates are faster than anticipated by numerical models on yearly time scales. We hypothesize that the rapid retreat is caused by un-represented, vigorous ice-ocean interactions acting within newly-formed cavities at the ice-ocean boundary.

位于西南极洲阿蒙森海盆（Amundsen Sea Embayment）的教皇冰川（Pope Glacier）、史密斯冰川（Smith Glacier）与科勒冰川（Kohler Glacier）在过去三十年中，经历了显著的海洋诱导冰架消融、冰川加速运动、冰体变薄以及接地线（grounding line）后退。该区域的冰川学背景为逆向基岩斜坡，极易触发海洋冰盖不稳定性（marine ice sheet instability）。本研究利用短重访周期的干涉雷达卫星（interferometric radar satellites）星座结合高精度表面高程数据，呈现了2014年以来上述三座冰川的接地线退缩观测结果。研究发现，冰川接地线形成了空间分布不均、尺度达千米级的潮汐诱导迁移带。在修正潮汐效应后，我们检测到持续的退缩模式，该模式与未接地冰的高消融速率相吻合，并伴随快速退缩的阶段性特征。2017年，教皇冰川在3.6个月内退缩了3.5千米，退缩速率达11.7千米/年。2016-2018年间，西史密斯冰川的退缩速率为2千米/年，科勒冰川为1.3千米/年。尽管2018-2020年退缩速率有所放缓，但上述年际尺度的退缩速率仍高于数值模型的预期结果。我们提出假说：快速退缩由冰-海洋边界处新形成的空腔内未被现有模型纳入的剧烈冰-海洋相互作用所引发。