Exegesis of Interferometric and Altimetric Observations in South Spitsbergen

• Main Author: Aleksey I. Sharov
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Hambergbreen; Hornbreen; Svalbard; Svalbard Archipelago; glacier; Tidewater; Spitsbergen
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.567.6061; http://dib.joanneum.at/integral/publications/obergurgl_sha_06.pdf

The present paper is based on the main outcomes of the INTEGRAL (EC FP6) and SIGMA (ESA AO No.2611) research projects devoted to enhanced modelling of glacier mechanics and studying the regime and changes of large European tidewater glaciers from satellite interferometry and altimetry. Synthetic aperture radar interferometry (INSAR) is regarded as a highly informative remote sensing method for glacier studies. Still, the exegesis [from Greek exegeisthai- to explain, interpret] or critical interpretation of the spaceborne interferograms taken over labile glacial environments is by no means straightforward and necessitates additional constraints and precise topographic reference models. Precipitous glacier faces, rapid changes and the lack of adequate reference models pose essential difficulties in geocoding of glacier interferograms and distinguishing between the impacts of ice surface topography and surface displacement on the interferometric phase. The underlying concept of the research is to facilitate the geometric processing of interferometric data and to compensate for the lack of reliable reference models in extensive glacial areas with precise altimetric and photogrammetric data, yet without or independently of the use of surveyed control points. The study area comprises the Sör-Spitsbergen National Park in south Svalbard, Norwegian Arctic with a total land area of approx. 4,500 km. The basic test site of smaller size covers the system of Hornbreen and Hambergbreen tidewater glaciers (H-H) situated in the southernmost part of the Svalbard archipelago (Fig. 1, a) and characterized with high rate of spatial changes. The character and causes of these changes are not fully understood at present. Up-to-date topographic maps and digital elevation models of the test site are either nonexistent or of limited quality and coverage. The geometric constraints needed for the precise interferometric modelling of the study glaciers were thus derived from spaceborne ICESat-GLAS altimetric transects and ASTER-VNIR imagery.