Glacier Calving-observations and Modelling

冰川崩解是指冰川边缘的冰破裂导致冰损失的过程。冰流模型用许多不同的方式描述冰裂，但对于最佳的方法仍没有达成共识。最近的研究表明，冰裂会导致一个不稳定的逃逸过程，一些对近未来全球海平面的高端预测依赖于实施这种不稳定的锋面退缩的模型。在这个项目中，观测和数值方法都被用来更好地理解产犊过程，以及如何最好地实现数值产犊。其目的是得出一种与观测结果非常一致的描述，同时在数值上具有足够的鲁棒性和灵活性，以适应当今大规模冰盖建模中使用的现有建模框架。特别令人感兴趣的是，某些类型的产犊规律可能会导致不稳定的退缩。这个想法将通过冰流数值模型和简化的分析模型进行调查和测试。观测数据将主要以格陵兰、冰岛和南极洲的遥感数据为基础，并将从冰岛的湖泊终止冰川收集额外的新数据集。南极松岛冰川的近未来演变将使用不同类型的产冰规律进行建模，并通过形式不确定性量化方法评估产冰公式的重要性。这项工作将与现有的国际研究项目和目前正在研究类似问题的其他小组紧密结合。作为NSFPLR-NERC资助项目的一部分，该学生将受益并为诺森比亚大学的工作做出贡献：过程，驱动因素，预测：利用冰/海洋耦合模型模拟下个世纪思韦茨冰川的响应。

Glacier calving is the process of ice loss through the breaking of ice from the edge of a glacier. Ice-flow models describe calving in a number of different ways, and there is still no consensus on the best approach. Recent work suggests that calving can give rise to an unstable run-away process and some of the higher-end predictions of near-future global sea level rely on models implementing such an unstable frontal retreat. In this project, both observational and numerical methods are used to better understand the calving process and how best to implement calving numerically. The aim is to arrive at a description that results in good agreement with observations, while at the same time being numerically robust and flexible enough to fit into an existing modelling framework used in large-scale ice-sheet modelling today. Of particular interest is the possibility of some types of calving-laws giving rise to an unstable retreat. This idea will be investigated and tested using numerical ice-flow models and simplified analytical models. Observational data will be primarily based on remote sensing data from Greenland, Iceland and Antarctica with additional new data sets to be collected from lake-terminating glaciers in Iceland. The near-future evolution of Pine-Island glacier, Antarctica, will be modelled using different types of calving laws, and the importance of calving formulations assess through formal uncertainty-quantification methodology. The work will be tightly integrated with existing international research projects and other groups currently working on similar problems. The student will benefit and contribute to work conduced at Northumbria University as a part of the NSFPLR-NERC funded project: Processes, drivers, predictions: Modeling the response of Thwaites Glacier over the next century using ice/ocean coupled models.