The Southern Ocean in a changing climate: open-ocean physical and biogeochemical processes
Convener: Lavinia Patara | Co-conveners: Camille AkhoudasECSECS, Alexander HaumannECSECS, Dan(i) Jones, Christian Turney

The Southern Ocean around the latitudes of the Antarctic Circumpolar Current is vital to our understanding of the climate system. It is a key region for vertical and lateral exchanges of heat, carbon, and nutrients, with significant past and potential future global climate implications. The role of the Southern Ocean as a dominant player in heat and carbon exchanges in present and future climate conditions remains uncertain. Indeed, the lack of observations of this system and its inherent sensitivity to small-scale physical processes, not fully represented in current Earth system models, result in large climate projection uncertainties. To address these knowledge gaps, the Southern Ocean has been the subject of recent observational, theoretical, and numerical modelling investigations. These efforts are providing deeper insight into the three-dimensional patterns of Southern Ocean change on sub-annual, multi-decadal and millennial timescales. In this session, we will discuss the current state of knowledge and novel findings concerning the role of the Southern Ocean in past, present, and future climates. These include (but are not limited to) small-scale physics and mixing, water mass transformation, gyre-scale processes, nutrient and carbon cycling, ocean productivity, climate-carbon feedbacks, and ocean-ice-atmosphere interactions. We will also discuss how changes in Southern Ocean heat and carbon transport affect lower latitudes and global climate more generally.