NSFPLR-NERC: Processes, drivers, predictions: Modeling the response of Thwaites Glacier over the next century using ice/ocean coupled models

我们建议对Thwaites冰川（TG）进行冰-海耦合数值模拟，以预测其未来对全球海平面变化的贡献，并使用三种最先进的冰流数值模型（ISSM， Úa和STREAMICE）与海洋模型MITgcm相结合，提供统计和结构误差估计。我们将实施和改进几个关键物理过程（裂冰、冰损伤、机械基础条件）的表示，这些过程要么没有包括在内，要么在以前的冰流建模工作中表现不佳。我们将量化不同提出的外部变化驱动因素的相对作用（例如，海洋引起的冰架变薄，冰架固定点的损失），并系统地探索TG的稳定性机制，目的是确定区分稳定和不稳定接地线退缩的内部阈值。使用逆方法，我们将从可用的雷达测量中获得新的物理一致的高分辨率（300米）冰厚数据集。此外，我们将生成几个关于冰速和高程变化率的新遥感数据集。这些将用于约束和验证我们的数值模型，并且作为独立数据集也将非常有价值。

We propose to conduct coupled ice-ocean numerical simulations of Thwaites Glacier (TG) to predict its future contribution to global sea level change, and to provide both statistical and structural error estimates using three state-of-the-art ice flow numerical ice-flow models (ISSM, Úa and STREAMICE) coupled with the ocean model MITgcm. We will implement and improve the representation of several key physical processes (calving, ice damage, mechanical basal conditions) that have either not been included, or poorly represented in previous ice-flow modelling work. We will quantify the relative role of different proposed external drivers of change (e.g., ocean-induced ice-shelf thinning, loss of ice-shelf pinning points), and explore systematically the stability regime of TG with the aim of identifying internal thresholds separating stable and unstable grounding line retreats. Using inverse methodology, we will produce new physically consistent high-resolution (300 m) data sets on ice-thicknesses from available radar measurements. Furthermore, we will generate several new remote sensing data sets on ice velocities and rates of elevation change. These will be used to constrain and validate our numerical models, and will also be highly valuable as stand-alone data sets.