Dynamics of the polar Southern Ocean response to climate change

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.