Post-1990s satellite monitoring of the Antarctic Ice Sheet has provided rich evidence of a highly dynamic system composed of relatively slow-moving central regions drained by ‘tributaries,’ in turn feeding into ‘ice streams’. The latter features, which often flow in excess of 1 km/year, are responsible for draining over 90% of the contemporary ice sheet, and as such represent the principal conduits through which changes in ice volume are translated into contributions to sea levels. Thus to understand the controls on ice sheet motion – e.g. what controls the distribution of ice streams/tributaries and source regions? what causes ice streams to migrate spatially? and what factors induce temporal variations in flow? – is to make a significant contribution to efforts to predict the future influence of the Antarctic Ice Sheet on global sea levels. Though it has been appreciated for many years that basal water is the most significant influence on alpine glacier motion, in stark contrast the role of subglacial water on Antarctic ice motion has remained poorly understood. In large part this has been due to a dearth of data on the water distribution beneath the ice sheet. This research project will utilise airborne radar data, GIS and geophysical techniques to map the distribution of subglacial water beneath parts of the Antarctic Ice Sheet. The resultant maps will be used to contribute towards improvements in modelling the flow of the Antarctic Ice Sheet and its contribution to sea level. The project will involve close collaboration with colleagues from the British Antarctic Survey, Cambridge.
Specific objectives:
1. Familiarisation with and organisation of airborne radar data.
2. Derivation of an automated routine for mapping variations in subglacial water across ice sheet beds from radar data.
3. Production of water distribution maps beneath key areas of the Antarctic Ice Sheet.
4. Using 2 and 3 in combination with GIS and remotely-sensed datasets to derive links between subglacial water distribution and ice flow.
5. Use of the above to contribute towards modelling the dynamics of the Antarctic Ice Sheet.
This project is a research collaboration with the NERC British Antarctic Survey and there will be opportunities for research visits to BAS HQ in Cambridge.
Application Deadline 28July2010
Read more: http://scholarship-positions.com/phd-scholarships-in-water-flow-beneath-the-antarctic-ice-sheet-supervisorsuk/2010/07/19/#ixzz0uC5j8p1r
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