Laboratory measurements of radar backscatter from bare and snow-covered saline ice sheets

Abstract

Abstract We performed experiments to collect radar backscatter data at Ku (13.4GHz) and C bands (5.3GHz) over simulated sea ice at the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) during the 1990 and 1992 winter seasons. These experiments were conducted over bare saline ice grown in an indoor tank and an outdoor pond facility. The radar data were calibrated using a complex vector calibration scheme to reduce systematic effects. In conjunction with the radar measurements we measured ice physical properties These measurements demonstrate that the dominant backscatter mechanism for bare saline ice is surface scattering. Both the copolarized and cross-polarized measurements compare favourably with the predictions of surface scattering models at two frequencies During the 1992 indoor tank experiment we applied four successive layers of snow (about 2.5 cm each) to the saline ice sheet after the ice thickness had reached about 12 cm. The backscatter at normal incidence dropped by l5dB and t...