Main supervisor: Doctor Steven Palmer, University of Exeter, Streatham Campus, Exeter
Co-supervisor: Doctor Stephen Cornford, University of Bristol
Co-supervisor: Dr Tim Barrows, University of Exeter, Streatham Campus, Exeter
Co-supervisor: Dr Anne LeBrocq, University of Exeter, Streatham Campus, Exeter
Co-supervisor: Dr Alastair Graham, University of Exeter, Streatham Campus, Exeter
The Greenland Ice sheet (GrIS) is the largest single contributor to sea level rise from the cryosphere, though large uncertainties exist in the projected rates of mass loss. Improved understanding of the controls on ice flow is required to better predict the future contribution of the GrIS to global mean sea level. Subglacial topography strongly influences the behaviour of the overlying ice and previous studies have used airborne ice-penetrating radar to derive gridded subglacial bed elevation datasets from ice thickness measurements acquired along discrete flightlines (Bamber et al., 2013). However, poor radar performance near the margin caused by ice crevassing introduces errors in derived bed elevation within ~10 km of the ice sheet margin. It is in these ice marginal areas, where ice is thinnest, that ice dynamics is most sensitive to topography. Therefore, there is a need for novel methods to provide improved knowledge of subglacial bed elevation near the margins of the GrIS.
The approach proposed in this PhD project is to use the glacier foreland, where we have detailed topographic information, as a proxy for understanding the less accessible subglacial regions. The successful candidate will use high resolution (2 m) satellite elevation data (Noh & Howat, 2015) acquired over Greenland to produce a geomorphological map of the foreland, identifying former ice-marginal features delineating former ice sheet extent. The resulting maps will be validated using a combination of airborne LiDAR measurements and field observations, including initial age estimation of features located at a former ice margin. The map will then be utilised in the following ways:
1. The topography data will be used to synthesise ice-penetrating radar datasets of subglacial topography over the currently ice free areas, assuming a range of typical airborne survey line spacing and orientations. These ’artificial’ subglacial topography grids will be compared with the known topography to investigate the sensitivity of derived subglacial topography datasets to the airborne survey design and flight line orientation.
2. Ice marginal features identified in the mapping will be used to constrain an ice sheet dynamical model, in order to investigate the Holocene retreat of this sector of the ice sheet.
It is intended that these analyses will lead to (i) a novel method for optimising airborne ice-penetrating radar survey design; (ii) improved methods for interpreting ice-penetrating radar datasets near ice sheet margins; and (iii), improved understanding of Holocene ice retreat in West Greenland.
The successful candidate will receive training in state of the art remote sensing and GIS techniques, and will also have the opportunity to map proglacial geomorphological features in SW Greenland to validate the remote sensing analysis. The candidate will be part of vibrant community of researchers at the University of Exeter, and amongst the wider GW4+ community.
Applicants should have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK. Applicants with a Lower Second Class degree will be considered if they also have Master’s degree. Applicants with a minimum Upper Second Class degree and significant relevant non-academic experience are encouraged to apply. All applicants would need to meet our English language requirements by the start of the project http://www.exeter.ac.uk/postgraduate/apply/english/ The majority of the studentships are available for applicants who are ordinarily resident in the UK and are classed as UK/EU for tuition fee purposes, however up to 9 fully funded studentships across the DTP are available for EU/EEA applicants not ordinarily resident in the UK. Applicants who are classed as International for tuition fee purposes are not eligible for funding.
The Closing deadline is 12:00, midday, Friday 20th May 2016. Interviews will be held on the 26th May 2016.
To apply: http://www.exeter.ac.uk/studying/funding/award/?id=1948
This project is one of a number that are in competition for funding from the NERC Great Western Four+ Doctoral Training Partnership (GW4+ DTP). The studentships will provide funding for a stipend (currently £14,057 pa), research costs and UK/EU tuition fees for 3.5 years for full-time students (part-time students pro-rata). Applicants must be classed as UK/EU for tuition fee purposes. Applicants who are classed as International for tuition fee purposes are not eligible for funding. For further details including academic eligibility criteria please see the advert on the University of Exeter website.
Bamber, J. L., Griggs, J. A., Hurkmans, R. T. W. L., Dowdeswell, J. A., Gogineni, S. P., Howat, I., Mouginot, J., Paden, J., Palmer, S., Rignot, E., and Steinhage, D. (2013) A new bed elevation dataset for Greenland, The Cryosphere, 7, 499-510, doi:10.5194/tc-7-499-2013.
Noh, M. J., & Howat, I. M. (2015). Automated stereo-photogrammetric DEM generation at high latitudes: Surface Extraction with TIN-based Search-space Minimization (SETSM) validation and demonstration over glaciated regions. GIScience & Remote Sensing, 52(2), 198-217.
How good is research at University of Exeter in Geography, Environmental Studies and Archaeology?
FTE Category A staff submitted: 11.20
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