A window to the ocean: Drivers of surface boundary layer turbulence in the Southern Ocean

The Southern Ocean acts as a globally important buffer to climate change by absorbing ~75% and ~50% of anthropogenic heat and carbon, respectively. But, the Southern Ocean is warming. Warmer oceans reduce the carbon uptake capacity of the ocean which can lead to enhanced global warming. Understanding the changing role of Southern Ocean heat uptake is therefore critical for predicting future climate.

However, simulated projections of heat uptake are strongly model-dependent and biased compared to observations.

A yet unquantified bias involves theprocesses that drive upper ocean turbulence and heat fluxes across the ocean mixed layer interface, a critical ‘window’ that allows exchanges of heat between the atmosphere and ocean interior.

In this project, I will draw on novel high-resolution direct observations of upper ocean turbulence and numerical experiments, to advance understanding and constrain uncertainties in the processes that drive upper ocean turbulence in the Southern Ocean.

I will develop upon a fine-scale parameterization of dissipation to harness 11-years of glider deployments spanning the Southern Ocean to ultimately determine the role of surface forcing, in particular, storms, in mediating heat fluxes between the surface and deep ocean.

By doing so, this project advances our understanding of how the ocean exchanges key climate variables, such as heat and carbon, with the atmosphere. This is cornerstone to interpreting current and future climate variability.