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、史密斯冰川与科勒冰川，在过去三十年中经历了加剧的海洋诱导冰架融化、冰川加速运动、冰体减薄以及接地线退缩（grounding line retreat）。该区域的冰川学背景为逆行基岩斜坡，易诱发海洋冰盖不稳定性（marine ice sheet instability）。本研究借助重访周期较短的干涉雷达卫星（interferometric radar satellites）星座组网观测数据，结合高精度地表高程数据，呈现了2014年以来上述三处冰川的接地线退缩观测结果。研究发现，冰川接地线存在空间异质性的千米级潮汐诱导迁移带。经潮汐效应校正后，我们检测到持续的退缩模式，该模式与未接地冰的高融化速率相契合，并伴随阶段性快速退缩事件。2017年，教皇冰川在3.6个月内退缩了3.5千米，折合年退缩速率达11.7千米/年。2016-2018年间，史密斯西冰川的年退缩速率为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均高于数值模型的预测结果。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涵盖的强冰-海洋相互作用所引发。