SAR Imaging of Waves in Ice

During the months of February and March of 1977 the Environmental Research Institute of Michigan (ERIM) X- and L-band dual polarized synthetic aperture imaging radar (SAR) was used to obtain radar imagery of sea ice off the Labrador coast under Project SAR '77. During the course of imaging specific areas, imagery of ocean swell patterns in consolidated pack ice was obtained. Surface data regarding direction, period and approximate wave height were collected in one particular area. A qualitative analysis of these swell patterns was undertaken using all the frequency-polarization combinations available from the system. Tilt modulation, roughness modulation, orbital velocity and parametric effects models for the SAR imaging of ocean waves were examined for applicability and results are presented. The ability to image these wave patterns is important in enabling ice observers to distinguish between areas of solid ice cover and semi- and unconsolidated pack.