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-海洋耦合数值模拟，以预测其未来对全球海平面变化的贡献，并使用三个最新的冰流数值模式(ISSM、ATRA和STREAMICE)与海洋模式MITgCM相结合来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(崩解、冰破坏、机械基础条件)的表示，这些过程要么没有包括在以前的冰流模拟工作中，要么没有得到很好的表示。我们将量化不同提出的外部变化驱动因素(例如，海洋导致的冰架变薄、冰架钉扎点的丧失)的相对作用，并系统地探索Tg的稳定机制，目的是确定区分稳定和不稳定接地线后退的内部阈值。使用逆方法，我们将从现有的雷达测量中产生关于冰厚度的新的物理上一致的高分辨率(300米)数据集。此外，我们将生成几个关于冰速和海拔变化率的新的遥感数据集。这些将被用来约束和验证我们的数值模型，并且作为独立的数据集也将具有很高的价值。

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.