Research highlights
Subpolar gyres and overturning circulation in the Southern Ocean
The Southern Ocean is arguably the central cog in the global ocean overturning circulation. In addition to connecting all the major ocean basins, the Southern Ocean facilitates the upwelling of carbon-rich waters from intermediate depths and the production of the dense bottom water that occupies most of the abyssal ocean. The Antarctic subpolar gyres bridge the regions of deep water upwelling, which mainly occurs within the Antarctic Circumpolar Current (ACC), and bottom water formation, which is formed exclusively along the continental margins of Antarctica. We aim to further our understanding of the dynamical coupling between the ACC, subpolar gyres, and the Antarctic margin.
Climate variability in the Southern Ocean
We seek to understand processes that modulate Southern Ocean surface climate variability. Relevant research topics include:
- Interannual and decadal trends in Southern Ocean sea surface temperature (SST) and sea ice trends
- Model-observation biases in Southern Ocean climate variability
- Mechanisms for extreme surface warming events across the Southern Ocean
- Teleconnections between the Southern Ocean and the broader Earth System
Sea ice-ocean feedbacks
A key feature of the sea-ice-covered Southern Ocean is the vertical arrangement of cold, fresh surface water above warmer, saltier deep water. The vertical flux of deep ocean heat strongly limits sea ice growth around Antarctica. Under extreme conditions, the ocean may vent enough heat to melt the overlying sea ice cover, creating what is known as an open-ocean polynya. These deep open-ocean polynyas can support deep convection that releases carbon from the usually sequestered ocean interior. We aim to improve our understanding of sea-ice-ocean interactions around Antarctica and how these dynamics will evolve in a warming climate.
Marginal Ice Zone dynamics and wave-ice interactions
As the polar regions experience increasingly warmer surface temperatures and stronger winds, the Marginal Ice Zone (MIZ) has emerged as a critical region of interest. The MIZ refers to the mosaic of loosely consolidated sea ice separating the open ocean from the thick, relatively homogenous pack ice. The MIZ is strongly influenced by surface ocean waves, which can fracture sea ice floes and accelerate melting. However, most climate models treat sea ice as a quasi-continuous medium with no representation of floe-scale dynamics
Subglacial discharge and seawater intrusions
Marine-terminating glaciers, such as those along the coastline of Greenland, often release meltwater into the ocean via subglacial discharge plumes. The conditions surrounding the genesis of these plumes remain poorly constrained, and little is known about the geometry of subglacial outlets and the extent to which seawater may intrude into them. We are interested in developing theories and models that describe the dynamics of subglacial seawater intrusions and their impact on ice-sheet stability.