Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596644
Title: Monitoring Arctic glaciers and ice caps using Satellite Remote Sensing
Author: Bingham, A. W.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 1998
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Abstract:
Routine monitoring of Arctic glaciers and ice caps is only possible using synthetic aperture radar (SAR). To make effective use of SAR, an algorithm to geocode SAR imagery is developed; the algorithm utilises a DEM to correct for terrain effects. Methods for collecting in situ data are also described; the data are then used to validate backscattering models. It is shown that during the summer melt season the physical optics model provides the best prediction of ERS-1 SAR backscatter from Arctic glaciers. High resolution satellite imagery is required to classify the surface facies on Arctic glaciers and ice caps. The potential of Landsat MSS and ERS-1 SAR for this application is explored. A Landsat TM image discriminates five distinct facies in cloud-free conditions, while a SAR image is unable to discriminate many surface facies. To improve the capability of SAR, backscatter values are normalised and dual-look images are used. Normalisation removes the dependency on incidence angle; this is achieved using the physical optics model. Images from an ascending and descending satellite pass are combined and it is demonstrated that up to five surface facies can be discriminated. It is estimated that the classification accuracy of a normalised, dual-look SAR image is about 65%, compared with 80% from a TM image; the SAR-derived ELA is within ± 5 m of the TM-derived ELA. A hybrid-classification scheme is applied to normalised, dual-look ERS-1 SAR imagery of Finsterwalderbreen and Austfonna, acquired at the end of a balance year. ELA measurements are used to calculate net mass balance and the potential of carrying out routine monitoring is assessed. The findings suggest that a combination of satellite reconnaissance and the direct glaciological method can provide a cost effective solution for routinely and systemically measuring the net mass balance of Arctic glaciers that are terminated by land and not highly deformed. However, the solution is presently not recommended for use on Arctic ice caps because of image requirements.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.596644  DOI: Not available
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