Mette Riger-Kusk
Ice discharge of an Antarctic outlet glacier: Darwin-Hatherton Glacial system
Mette Riger-Kusk, Gateway Antarctica
Supervisors
Wendy Lawson, Department of Geography, University of Canterbury
Wolfgang Rack, Gateway Antarctica, University of Canterbury
Brian Anderson, Antarctic Research Centre, Victoria University of Wellington
The Darwin-Hatherton outlet glacial system flows from the East Antarctic Ice Sheet through the Transantarctic Mountains into the Ross Ice Shelf , which is predominantly fed by the West Antarctic Ice Sheet. Recent changes in ice thickness of this glacial system have previously been used to infer variations of the grounded Ross Ice Sheet during the last glaciation. However, differing conclusions have been reached about the maximum ice thickness of the ice sheet and the rate of subsequent retreat. The discrepancies are primarily a result of insufficient knowledge of key parameters of the Darwin-Hatherton glacial system such as ice thickness, mass balance, climate and the ages of glacial sediments in neighbouring ice-free valleys. This research aims to examine the ice dynamics of the Darwin-Hatherton glacial system using geophysical and numerical modelling techniques.
The PhD research will focus on the following three questions:
- What are the driving forces and physical processes that control the response and behaviour of outlet glacial systems draining from the EAIS through the Transantarctic Mountains?
- What is the amount and rate of recent change in such a glacial system?
- How would such a glacial system respond to future climatic change?
A detailed ground penetrating radar survey was carried out in the 2008/09 Antarctic field season, investigating ice thickness, internal structures, ice temperature conditions and grounding line position of the Darwin-Hatherton glacial system. When the processing of the data from this survey has been finalised, the results will be utilised with other relevant information from the study area in adapting a numerical ice flow model. The numerical model will then be employed to explain both recent changes within the glacial system and responses to possible future climatic forcing. By investigating the dynamics of the Darwin-Hatherton glacial system, the research will thus contribute to an improved understanding of the behaviour of the West and East Antarctic Ice Sheets.