Change in the ice speed and mass balance of the Antarctic Ice Sheet, from Earth Observation satellite data

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Satellite Earth Observation has revolutionized our understanding of the remote and inaccessible Polar Regions. Without this critical resource we would have a far less complete understanding of which regions are changing, the timing and pace at which events occur, and what physical mechanisms are responsible for driving change. In Antarctica, satellite data has been vital for revealing the continent-wide spatial pattern of ice flow; for uncovering dynamic imbalance and the associated large sea level contribution of the marine-based West Antarctic Ice Sheet; for mapping the seasonal growth and decay of sea ice extent; and for measuring the size and recovery of the Ozone hole. During the last 30-years, individual ice streams in Antarctica such as Pine Island Glacier, have increased in speed by over 42% since the early 1990's, and are now known to be dynamically imbalanced. However, despite a clear long-term trend for increasing ice velocity in many regions, the observed speed up has not been constant through time, and multiple years with no significant change have also been observed. It is necessary to make present day measurements of ice velocity to provide an independent means of measuring ice mass loss from the most rapidly changing regions of this vast ice sheet.This project offers an exciting opportunity to work at the interface of climate and space science, making an important contribution to international efforts to study the effects and impact of climate change. This PhD student will gain a detailed technical understanding of how to process Synthetic Aperture Radar (SAR) data from a large number of Earth Observation satellites, including ERS-1/2, TerraSAR-X, Sentinel-1, using multiple processing techniques, such as interferometry (InSAR) & feature tracking, to make measurements of ice speed. The measurements of ice speed will be used in combination with bed and ice surface topography to compute the ice flux, and then mass balance, of individual glaciers on the Antarctic Ice Sheet. The ice speed measurements will be analysed to detect change in speed over time, and this will be combined with complimentary observations, such as the calving front location and ice thinning, to advance our understanding of the physical mechanisms driving change. These results will be used to improve and extend the ice sheet contribution to present-day sea-level rise, a topic of wide societal importance, and will enable us to better predict how the ice sheet will change in the future. The student will lead at least three journal papers on these important science topics during the course of their PhD, and may have the possibility of undertaking a Polar field campaign. The PhD student will be based within the Centre for Polar Observation and Modelling (CPOM) at the University of Leeds, and will therefore have valuable opportunities to work with and attend meetings at the European Space Agency (ESA), and to engage with a wide range of international scientific collaborators. A studentship within CPOM provides a fantastic opportunity to actively collaborate with a large team of land and sea ice observation and modelling experts at universities across the UK. The project provides a high level of training in: (i) satellite remote sensing; (ii) polar fieldwork; (iii) glaciology; (iii) data analysis and visualization; (iv) calibration and validation of satellite systems; and (v) scientific writing. The successful applicant will have access to a broad spectrum of specialist training in Earth Observation and glaciology, in addition to the extensive University of Leeds workshops on a range of topics, including scientific programming through to managing your degree. Applicants will hold good first degree (first or high 2.1) or Masters degree in physics, maths, Earth science, climate science, Earth observation or a related discipline. Expertise in computer programming, while not required, will be a valuable asset.