University of Tasmania, Australia

Empirical sea ice modelling for East Antarctica.

Level: MSc/PhD

Improved understanding and modelling of Antarctic sea ice dynamics is critical to the development of biogeochemical and foodweb dynamics models for the Southern Ocean. However, progress with mechanistic (or 'process-oriented') models of sea ice dynamics has been slow, in part due to the complexity of processes that affect formation and melting, extent and concentration of sea ice. The development of empirical models for sea ice dynamics provides a potential work-around to problems with mechanistic models, and indeed there are several reasons why empirical models might be preferable in informing biogeochemical and foodweb dynamics in end-to-end models of biophysical systems in the Southern Ocean.

An empirical model framework could comprise: (i) probabilistic functions of geostatistical properties to represent the dynamics of sea ice classes (which could be fitted using remotely sensed data), (ii) movement of ice columns determined by sea ice motion vectors, and (iii) representation of confluence into an area and dissipation out of an area. Key questions in developing such a framework include data requirements for model fitting and validation, whether an empirical model is likely to be sufficient for the purposes of understanding and modelling spatial and temporal patterns of sea ice primary production, and whether such a model could be used to project potential future changes in sea ice primary production under climate change scenarios.

This project will involve the application of geostatistics, time-series analysis and probabilistic functions to extract data and fit empirical models of sea ice dynamics. The initial part of the project will contribute to further development of classification techniques for remotely sensed sea ice data. The second stage of the project will be to develop statistical models using different combinations of physical variables to try to reproduce observed changes in the distribution of ice classes.

The successful applicant will join an active team within the Antarctic Climate and Ecosystems Cooperative Research Centre that is undertaking research to assess climate change impacts on Antarctic marine ecosystems. The successful applicant will be supported in the following areas:

(i)   Developing expertise in empirical modelling;

(ii) Understanding and applying techniques in marine remote sensing; and

(iii) Communicating research findings, particularly the representation of empirical models and data to inform the development of end-to-end models of biophysical systems in the Southern Ocean.

Nominal supervisors: Andrew Constable (contact: 6232 3558, Andrew.Constable@aad.gov.au), Jess Melbourne-Thomas, Stuart Corney, Rob Massom