Bathymetry of the Southern Ocean. Bold lines indicate density fronts of the Antarctic Circumpolar Current (ACC). From Orsi et al., 1995.

The Southern Ocean is one of the key drivers of the Earth’s climate. Circumnavigating the Antarctic continent and connecting the Pacific, Indian and Atlantic ocean basins, it plays a critical role in sustaining ocean biodiversity, global ocean heat uptake and carbon dioxide absorption. So, it is very important to fully understand the circulation dynamics of the Southern Ocean and how this may change in response to a changing climate.

The various forcings and resultant circulation patterns in the Southern Ocean. From Morrison et al., 2015.

The Southern Ocean is characterised by brine rejection due to sea ice formation near Antarctica, a sharp thermal gradient as you move northwards and strong, persistent westerly winds around Antarctica. All of these factors significantly impact circulation patterns in the Southern Ocean, resulting in a strong current known as the Antarctic Circumpolar Current (ACC). There is also deepwater formation near Antarctica, which travels northward all the way up to the North Atlantic.

Modern large-scale ocean models which seek to shed light on this topic are unable to fully characterise small-scale ocean processes like convection. My research seeks to address this shortfall, and I use a high-resolution, turbulence-resolving model of the Southern Ocean to do so. By varying the surface wind and temperature, I am able to quantify the overturning circulation of the Southern Ocean with the presence of convection.


Sample output from my high-resolution simulations. 3D contour is temperature and colouring is kinetic energy.

My PhD is slated to finish in May 2020.