Dynamics of the polar Southern Ocean response to climate change

南极极地海洋是大气、冰冻圈和海洋之间强烈而复杂的相互作用区域。它们对地球气候的影响与它们的面积极不相称。它们的空气-海冰相互作用对南极冰盖和全球海平面的稳定性、南极海冰的体积和范围、地球的反照率以及南极海底水的产生至关重要。南极海底水为全球海洋深渊的大部分地区降温和通风。这些极地海洋目前正在经历南极冰盖淡水排放的显著增加，以及部分与人为温室气体排放有关的大气强迫的重大十年尺度变化。然而，关于这些变化的作用力对邻近海洋的影响，目前的知识状况极为有限。这主要是由于在海冰存在的情况下从海洋遥感卫星获得观测资料的复杂性，海冰几乎常年覆盖该区域。该项目将利用并加强一项新技术，提取冰覆盖海洋的高度海平面测量数据，并将该技术的发现与最先进的冰-海洋模型的结果结合起来，研究过去二十年来极地南大洋环流变化的动力学及其物理驱动因素。

The Antarctic polar seas are regions of intense, complex interactions between the atmosphere, cryosphere and ocean. Their influence on Earth's climate is greatly disproportionate to their area. Their air-sea-ice interactions are central to the stability of the Antarctic Ice Sheet and global sea level, the volume and extent of Antarctic sea ice, the Earth's albedo, and the generation of the Antarctic Bottom Water that cools and ventilates much of the global ocean abyss. These polar seas are presently experiencing a significant increase in freshwater discharge from the Antarctic Ice Sheet and major decadal-scale changes in atmospheric forcing, linked partly to anthropogenic greenhouse gas emissions. The current state of knowledge concerning the impact on the adjacent ocean of these changing forcings is, however, extremely limited. This is largely owing to the complexity of obtaining observations from ocean-sensing satellites in the presence of sea ice, which covers the region near-perennially. This project will draw on and enhance a novel technique to extract altimetric sea level measurements of the ice-covered ocean, and will combine the findings from this technique with results from a state-of-the-art ice-ocean model to investigate the dynamics of the polar Southern Ocean circulation variability and its physical drivers over the last two decades.