Sinks and Sources: Closing heat and buoyancy budgets at the Antarctic margins

Observational and modeling studies have increased our understanding of how ocean dynamics impact the transport of warm waters towards Antarctic ice shelves. Yet these studies have largely focused on localized processes occurring at the continental shelf break. There is a growing appreciation that changes to ocean stratification over the continental shelf can influence these transport pathways by modifying mixing processes as well as the structure of boundary currents, such as the Antarctic Slope Current and the Antarctic Coastal Current. This talk will first address the mechanisms that contribute to heat loss over the continental shelf and along the coast, which shape both the heat supply to the continental shelf and large-scale climate properties in the Southern Ocean. Finally, the talk will describe the three-dimensional structure of the West Antarctic stratification and overturning circulation. A key result is that inter-shelf-sea exchange forms a key component of a closed overturning circulation, with parallels to the global ocean’s three-dimensional overturning circulation.