Analysis of bottom morphology of the David Glacier-Drygalski Ice Tongue, East Antarctica

• Main Authors: Tabacco, I. E., Bianchi, C., Chiappini, M., Zirizzotti, A., Zuccheretti, E.
• Other Authors: Tabacco, I. E.; Sezione Geofisica, Dipartimento di Science della Terra, Università degli Studi di Milano, I-20129 Milano, Italy, Bianchi, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Chiappini, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Zirizzotti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Zuccheretti, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Sezione Geofisica, Dipartimento di Science della Terra, Università degli Studi di Milano, I-20129 Milano, Italy, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia
• Format: Article in Journal/Newspaper
• Language: English
• Published: International Glaciological Society 2000
• Subjects: glaciers; radio-echo-sounding; radio propagation in the ice; 02. Cryosphere::02.02. Glaciers::02.02.99. General or miscellaneous; 02. Cryosphere::02.02. Glaciers::02.02.07. Ocean/ice interaction; 02. Cryosphere::02.02. Glaciers::02.02.10. Instruments and techniques; David Glacier; Drygalski; Drygalski Ice Tongue; East Antarctica; Annals of Glaciology; Antarc*; Antarctica; Sea ice
• Online Access: http://hdl.handle.net/2122/4082

Data from radio-sounding measurements have been analysed to determine the ice thickness and the bottom morphology of Drygalski Ice Tongue, Antarctica. The morphology and the structure of the bottom surface has been studied through an electromagnetic interpretation. A function that includes the gain/loss due to the geometrical shape of the reflecting surfaces has been calculated. Such a function has been evaluated assuming some physical electromagnetic quantities (the temperature of the glacier, the complex dielectric permittivity of ice, sea ice and sea water). The ice-water interface shows both concave and convex faces toward the sounding system, producing a focusing or defocusing effect, detected as absolute (or relative) amplitude variation in the echo signal. It is shown that the calculated function follows quite well the observed bottom rippled surface of the glacier tongue estimated from the time-arrival measurements of the echo signal. Published 47-51 3.8. Geofisica per l'ambiente JCR Journal reserved