Quasi-parabolic reflecting bottom surfaces of the Drygalski Antarctic floating ice tongue

• Main Authors: Bianchi, C., Chiappini, M., Tabacco, I. E., Zirizzotti, A., Zuccheretti, E.
• Other Authors: Bianchi, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Chiappini, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Tabacco, I. E.; Università di Milano, Sezione Geofisica, Milano, Italy, Zirizzotti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Zuccheretti, E.; stituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Università di Milano, Sezione Geofisica, Milano, Italy, stituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2001
• Subjects: radio echo sounding; radio glaciology; glacier ice tongues; 04. Solid Earth::04.02. Exploration geophysics::04.02.05. Downhole; radioactivity; remote sensing; and other methods; Antarctic; East Antarctica; Ross Sea; Drygalski; Antarc*; Antarctica
• Online Access: http://hdl.handle.net/2122/1245

Very high frequency deep radio sounding systems for ice thickness measurements are practically the only useful apparatuses for large scale radar flight surveys in polar regions. The morphology of the bottom surface of an Antarctic floating ice tongue, in the Ross Sea area, East Antarctica, was studied using the arrival times of signal echoes of the radio sounding system. The amplitude variations of radar signals from the reflecting surface were analyzed to determine the gain or the loss of the reflectors. Such surfaces show quasi-parabolic geometrical shapes at the ice/water interface with both concave and convex faces towards the sounding system. Electromagnetic analysis performed on radar echoes indicates that amplitude variations detected by the antenna are focusing or defocusing effects only due to the reflector's shape. A factor in the radar equation that represents the surface shape when coherent reflectors are involved is introduced. This factor allows us to determine more precisely the morphology and electromagnetic characteristics of the interface between the media investigated by means of radio echo sounding. JCR Journal open