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Please draw this to the notice of any potential students who may be interested. -------------------------------------------------------------------------------- EPSRC STUDENTSHIP - DEPARTMENT OF GEOMATICS, UNIVERSITY OF NEWCASTLE UPON TYNE The Department of Geomatics, University of Newcastle upon Tyne, has an EPSRC- funded project PhD studentship available from 1 September 1999 to work on the following topic, jointly supervised by Dr Peter Clarke and Prof Geoff Blewitt (also at University of Nevada at Reno). Normal EPSRC eligibility rules apply. "Correction of tropospheric artefacts in Synthetic Aperture Radar interferograms using GPS observations" Interferometric Synthetic Aperture Radar (InSAR) is a recent technique which has wide applications in the field of Earth deformation monitoring. Previous results have demonstrated spectacular success in providing widespread spatial information regarding the deformation associated with large earthquakes and volcanic eruptions. For smaller, long-term deformation rates, some problems remain. In particular, since both SAR scenes that make up the interferogram represent "snapshots" of the ground and atmosphere, there is no redundancy of information to enable atmospheric biases to be estimated. A change in atmospheric conditions between SAR passes will therefore result in an artefact in the interferogram. The Global Positioning System (GPS) is a precise geodetic measurement system that operates at similar microwave frequencies. In this case observations are made at discrete ground receivers over a period of minutes to days, providing redundancy of information which enables atmospheric signal delays to be estimated along with the receiver position. Recent work has shown that GPS measurements of tropospheric water vapour (the primary unmodelled cause of microwave signal delay) can be equal or better in accuracy compared with previous techniques (water vapour radiometers and radiosondes). The potential exists to unite these two techniques of deformation monitoring: to combine the redundancy and atmospheric information from the discrete GPS receivers with the blanket coverage of InSAR. This project will investigate the use of GPS for tropospheric signal delay estimation and its application to contemporaneous SAR measurements. Data from a variety of test areas displaying varying atmospheric and deformational signals, including Mt Etna (Italy), Yucca Mountain (Nevada), Greece and the Newcastle area will be used for analysis. The student will receive training in GPS theory and fieldwork, SAR processing and analysis, computing, and the management and analysis of large datasets. Funds will be provided for the student to spend time in the field and at the institutions of both supervisors. The studentship would suit a graduate with a first or upper second class degree in physics, earth science, mathematics, geomatics or engineering and an interest in geophysical monitoring. Other geoscientists with a good mathematical background are also encouraged to apply. Enquiries should be addressed to Peter Clarke (contact details below). Interested applicants should send a full CV, together with the names and contact details of three referees, to the address below. -- Dr Peter CLARKE, Dept of Geomatics, University of Newcastle, NE1 7RU, UK Tel: +44 (0)191 222 6445 (dept) or +44 (0)191 222 6351 (direct) Fax: +44 (0)191 222 8691 http://www.staff.ncl.ac.uk/peter.clarke/ -------------------------------------------------------------------------------- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%