Dynamics of the polar Southern Ocean response to climate change

南极极地海洋是大气层、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其面积极不成比例。它们的空气-海冰相互作用对南极冰盖的稳定性和全球海平面、南极海冰的体积和范围、地球的冰和南极底层水的产生至关重要，南极底层水冷却和通风了全球海洋深渊的大部分。这些极地海洋目前正经历着南极冰盖淡水排放的显著增加和大气强迫的重大十年尺度变化，部分与人为温室气体排放有关。然而，目前关于这些变化的强迫对邻近海洋的影响的知识极为有限。这在很大程度上是由于在该区域几乎常年覆盖海冰的情况下从海洋遥感卫星获得观测结果的复杂性。该项目将借鉴和加强一种新技术，以提取冰盖海洋的高度海平面测量值，并将把这种技术的结果与最先进的冰-海洋模型的结果相结合，以调查过去二十年来极地南大洋环流变化的动态及其物理驱动因素。

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.