Abstract

For any external attendees, please email Birgit Rogalla (birgal at bas.ac.uk) and Yohei Takano (yokano at bas.ac.uk), so we can help arrange access to BAS .

The continental shelf at the boundary of Antarctica mediates interactions between the Antarctic ice sheet and the global ocean. Considering its climatic implications, the circulation on the shelf, in the nearby deep ocean, and exchange between the two, remains under-constrained. In this seminar, I will present results from two recent studies that explored different aspects of this circulation, with a particular focus on heat and freshwater transports, their natural variability, and their response to forced change. In the first study, I will explore the interannual variability of heat transport toward the West Antarctic peninsula, as represented in an observationally-constrained model. We show that this heat transport is mediated by the strength and extent of the Ross Gyre, itself a function of local wind stress curl and sea ice cover. In the second study, I will elucidate the role of the Antarctic slope current in controlling the export of ice sheet-derived meltwater from the shelf to the open ocean. I will show, via the divergent solutions of two climate models, how this process impacts Antarctic Bottom Water formation and global overturning. In presenting both studies, I will highlight the open questions they reveal, and point to current work that seeks to address them.