Imaging Subglacial Topography by a Synthetic Aperture Radar Technique

G.J. Musil, C.S.M. Doake
1987 Annals of Glaciology  
A synthetic aperture radar (SAR) technique has been used to image part of the grounding-line region of Bach Ice Shelf in the Antarctic Peninsula. The radar was sledge-mounted and operated in a pulsed mode with a carrier frequency of 120 MHz. The coherently detected output was recorded photographically as in-phase and quadrature components. Because the system was essentially stationary for each measurement, there was no doppler information about the reflecting points as in the more commonly used
more » ... more commonly used airborne and satellite-based SARs. Instead, the phase history was used directly to identify point targets by a correlation method. Three sounding runs were carried out over the grounding line to give views of the area from separate directions. An aperture length of 104 m was necessary to achieve 8 m resolution in the along-track direction for an ice thickness of 290 m. The mapped swath was 88 m wide. Corrections to the data were made to allow for density variations and absorption in the ice. The back-scatter coefficient showed greater variations in echo strength over grounded ice compared with floating ice and texture analysis of the radar image revealed a statistically significant difference between these two regimes.
doi:10.1017/s0260305500000562 fatcat:mfzp3aadandq7g5yppwq2fs4qe