Stability of marine basins in the Antarctic Peninsula Ice Sheet from remote sensing

该项目将评估共同位于埃尔斯沃斯陆地之下的海洋冰盖盆地的当前和未来的稳定性，埃尔斯沃斯陆地是连接西南极和南极半岛冰盖的地区。众所周知，海洋冰盖盆地，即位于海平面以下的冰盖的一部分，特别容易退缩，因此具有极大的促进未来全球海平面上升的潜力(DeConto和Pollard，2016；Mercer，1978)，这些过程在西南极的阿蒙森海湾得到了大量研究(Bingham等人，2017；Scambos等人，2017)。尽管过去十年的一些研究也引起了人们对西南极埃尔斯沃斯陆地也容易受到海洋冰盖不稳定影响的关注(Bingham等人，2012年)，并且目前显示出这种不稳定的迹象(Hogg等人，2017年；Wouters等人，2015年)，但该地区仍然相对缺乏数据，无法很好地估计其未来的退缩速度和海平面贡献。解决这一根本的知识差距并阐明埃尔斯沃斯陆地冰的潜在消退对不久的将来海平面上升构成的危险是该项目的重点。拟议研究的目的、目标和方法该项目的主要目的是评估位于南极洲西部和南极半岛之间的埃尔斯沃斯陆地海洋盆地的近期(200年后)稳定性。这包括以下目标：1.从地球观测数据集中为埃尔斯沃斯陆地汇编当代冰川变化的时间序列(冰面速度、表面高度和基准线的变化)；2.追踪整个埃尔斯沃斯陆地上的冰层(被视为等时线或等年龄表面)，从而利用来自相邻层的年龄限制-跟踪和连接到西南极冰芯年龄深度剖面-最终目的是限制该地区最古老的冰，从而为其过去的稳定性提供线索；3.探索机器学习方法在追踪地球物理数据中的岩层和/或从地球观测数据编制当代变化时间序列方面的应用。

This project will assess the current and future stability of marine ice-sheet basins that collectively underlie Ellsworth Land, the region that connects the West Antarctic and Antarctic Peninsula Ice Sheets. It is well known that marine ice-sheets basins, defined as the parts of the ice sheets that are grounded below sea level, are particularly vulnerable to retreat and therefore have significant potential to contribute to future global sea-level rise (DeConto and Pollard, 2016; Mercer, 1978), and these processes are much studied in West Antarctica's Amundsen Sea Embayment (Bingham et al., 2017; Scambos et al., 2017). Despite some studies over the last decade also drawing attention to West Antarctica's Ellsworth Land also being vulnerable to marine ice-sheet instability (Bingham et al., 2012) and currently showing signs of this being underway (Hogg et al., 2017; Wouters et al., 2015), the region remains relatively data-poor for good estimates of its future retreat rates and sea-level contributions. Addressing this fundamental knowledge gap and elucidating the dangers to near-future sea-level rise posed by potential retreat of ice from Ellsworth Land form the focus of this project. Aim, objectives and methods of the proposed research The main aim of the project is to assess the near-term (200 years into the future) stability of the Ellsworth Land marine basin lying between West Antarctica and the Antarctic Peninsula. This comprises the following objectives: 1. To compile for Ellsworth Land time series of contemporary glaciological change (changes to ice-surface velocity, surface elevation and the grounding line) from Earth Observation datasets; 2. To track englacial horizons (treated as isochrones, or surfaces of equal age) across Ellsworth Land, and thereby place age constraints on its deep ice, using age constraints from adjacent layer-tracking and links to West Antarctica's ice core age-depth profiles - with the ultimate aim of constraining what is the oldest ice in the region, and hence give clues to its past stability; 3. To explore the application of machine-learning methods for tracking englacial layers in geophysical data and/or compiling time series of contemporary changes from Earth Observation data.