Climate sensitivity of western Antarctic Peninsula ice shelves (CSAPIS)

南极洲半岛西部的大多数冰架在过去几十年中显示或经历了相当大的退缩甚至完全解体。最近的研究将其部分与温暖的绕极深层水（CDW）的上涌联系起来，这应该特别影响南极半岛西南部地区。然而，确切的过程和机制以及该地区对进一步冰架和冰川变薄和退缩的敏感性尚不清楚或没有得到很好的限制。这部分是因为缺乏观测和建模工作的要求。在这项研究中，我们建议分析遥感数据的时间序列，以获得各种冰川学变量，如表面速度，表面高程变化，接地线和冰锋位置以及结构变量。我们将为南极半岛西南部的整个大规模集水区提供这种分析。我们将联合收割机的遥感数据集计算时间上的高分辨率的冰量排放估计与两个独立的方法。这些数据集将对冰盖质量平衡相互比较工作或政府间气候变化专门委员会（气候专委会）的下一份报告等国际努力作出贡献。然后，上述遥感产品将用于校准和验证该区域冰架后退的前向模拟和冰动力模型。所采用的冰流模型是Blatter-Pattyn近似的冰盖和海平面系统模型（ISSM），在接地线处的分辨率可达200-500 m。数值模拟研究的目的是双重的。在第一步中，最近正在进行的变化的机制进行调查。在这里，我们专注于冰架支撑的重要性和冰架融化的影响（冰-海洋相互作用）。这一步骤在很大程度上建立在评估瞬态模拟质量的遥感产品的基础上。第二步，对冰架和冰川支流的未来稳定性进行估计。根据协调区域降尺度试验（Polar-CORDEX）建模战略，重点是代表性浓度路径（RCP）8.5情景。为了解决这些问题，我们将依靠合适的海洋和大气场。特别是，我们努力使用正在进行的努力与有限元海冰海洋模型（FESOM）的数据集，包括冰架腔的建模框架（正在进行的ECHAM 6-FESOM耦合的气候模型相互比较项目（CMIP）6和极地CORDEX活动）。

Most ice shelves on the western Antarctic Peninsula show or have experienced considerable retreat or even complete disintegration in the last few decades. Recent studies have linked this partly to upwelling of warm Circumpolar Deep Water (CDW), which is supposed to influence particularly the southwestern Antarctic Peninsula region. However, the exact processes and mechanisms as well as the sensitivity of the region to further ice shelf and glacier thinning and retreat are not known or not well constrained. This is partly because of lacking observations and the demanding modelling efforts. In this study, we propose to analyse time series of remote sensing data to derive various glaciological variables such as surface velocities, surface elevation change, grounding line and ice front positions as well as structural variables. We will provide this analysis for entire large-scale catchments on the southwestern Antarctic Peninsula. We will combine the remote sensing data sets to compute temporally high-resolution ice mass discharge estimates with two independent methods. Those data sets will form a contribution to international efforts such as Ice sheet Mass Balance Inter-comparison Exercise (IMBIE) or the next report of the Intergovernmental Panel of Climate Change (IPCC). The above-mentioned remote sensing products will then be used for calibration and validation in forward simulations for the ice shelve retreat in the region with an ice dynamic model. The employed ice flow model is the Ice-Sheet and Sea-level system model (ISSM) in Blatter-Pattyn approximation and an envisaged resolution down to 200-500 m at the grounding line. The aim of the numerical modelling studies is two-fold. In a first step, the mechanisms for recent ongoing changes are investigated. Here, we focus on the importance of ice-shelf buttressing and the impact of ice shelf melting (ice-ocean interaction). This step heavily builds on remote sensing products assessing the quality of the transient simulations. In a second step, the future stability of ice shelves and glacier tributaries is estimated. In accordance with the COordinated Regional Downscaling EXperiment (Polar-CORDEX) modelling strategy, the focus is on the Representative Concentration Pathway (RCP) 8.5 scenario. To tackle these questions, we will rely on suitable oceanic and atmospheric fields. In particular, we strive to use data-sets of the ongoing efforts with the Finite Element Sea ice-Ocean Model (FESOM) to include ice shelf cavities in the modelling framework (ongoing ECHAM6-FESOM coupling for the Climate Model Intercomparison Project (CMIP) 6 and from the Polar-CORDEX activity).