Modelling downward carbon flux in the Southern Ocean: linking ocean midwater ecology and biogeochemistry


  • Philip Boyd ( IMAS
  • Co-Supervisors: Ben Scoulding (CSIRO)
  • Rowan Trebilco (IMAS)
  • Kerrie Swadling (IMAS)

The Project

The oceans act as major sinks of atmospheric carbon. The biological pump is the ocean’s biologically driven carbon sequestration system. It has many pathways for sequestering carbon (e.g. gravitational pump and particle injection via midwater biota), however, understanding and linking these pathways is not easy and therefore has seldom been attempted. Often the models designed to quantify downward particulate carbon flux in the oceans lack information on key pathways and their parameterization may only focus on a limited number of these pathways. Development of a holistic model which links these ecological and biogeochemical pathways will provide a much more comprehensive and accurate picture of downward particulate carbon flux across the oceans. Such a model will enable researchers to track the oceans’ ongoing ability to sequester carbon in response to climate change.

This project will connect pathways for carbon sequestered by the biological pump in both subpolar and polar waters of the S. Ocean. By working closely with relevant experts who straddle midwater ecology and biogeochemistry, the successful student will bridge the gap between different areas of research to develop a truly ocean-wide downward particulate carbon flux model which importantly builds links between these two disciplines. The model will be used to establish a firm baseline on the magnitude of carbon sequestered by the biological pump which will enable us to detect future changes in the downward carbon flux due to climate change. By tracking carbon export will be able to see whether this flux is maintained, enhanced, or diminished in the subantarctic and polar S. Ocean in response to climate change.

Essential Skills

  • Strong maths/statistical background
  • Strong analytical skills, especially with scientific analysis/programming software
  • Strong English written and oral communications
  • Demonstrated record of independent research (e.g. Honours, or Masters by Research)
Authorised by the Executive Director, Institute for Marine and Antarctic Studies
March 4, 2022