About the project
Reduced Antarctic sea-ice since 2016 may have promoted the growth of eddies, enhancing heat transport to polar seas. This project investigates whether these changes have warmed the upper-ocean, contributing to persistently low sea-ice extent in recent years. The hypothesis explores the relationships between diminished sea-ice cover, increased eddy activity, and shifts in ocean dynamics.
Sea-ice acts to damp surface-intensified eddies that flow under it by exerting friction on the eddies’ surface (Meneghello et al., 2021). Since 2016, the rapid decline in Antarctic sea-ice extent, after years of unexpected growth, suggests a potential shift to a new climatic state (Purich & Doodridge, 2023). This drop in sea ice extent is likely linked to rising upper-ocean temperatures, yet its drivers remain unclear.
The Antarctic Circumpolar Current (ACC), known for its intense eddy activity, has shown increasing eddy kinetic energy (EKE) over the past two decades, possibly driven by wind changes (Martinez Moreno et al., 2019). Surprisingly, little research has focused on what happens when these eddies encounter the marginal ice zone (MIZ).
This project seeks to uncover whether the eddy field around Antarctica has changed since 2016, and how these changes affect southward heat transport. The hypothesis to be explored is that reduced sea-ice cover allows more eddies to travel southward, carrying more heat below the MIZ and potentially warming the upper ocean, which could explain the persistently low sea-ice extent observed in recent years.
To address this hypothesis, the candidate will leverage diverse datasets, including remote sensing (conventional, under-ice, and high-resolution SWOT), ocean modeling (NEMO and MOM), and machine learning techniques to explore the relationship between diminished sea-ice cover, increased eddy activity, and shifts in ocean dynamics.
Supervisors
As well as Prof. Alberto Naveira Garabato, you will also be supervised by organisations other than the University of Southampton, including:
- Dr. Tiago Segabinazzi Dotto from the National Oceanography Centre
- Dr Adele Morrison from the Australian National University
- Dr Yevgeny Aksenov from the National Oceanography Centre
- Dr Tasha Snow from the University of Maryland