GeoSAR P/X-band single pass IFSAR over arctic ice

Abstract

The GeoSAR single-pass P-band and X-band IFSAR system was employed 09 April 2012 to acquire ice data over the city of Barrow, Alaska, extending into the Chukchi Sea to the west and the Beaufort Sea to the northeast. The acquisition covered two back-to-back flights obtaining high quality singlepass interferometric X-band and P-band data. Some of the Pband data was collected in fully polarimetric mode. Ground control was established by two geographically separated dualband corner reflectors. Nadir looking lidar profiler data was acquired over the majority of the project. The acquisition was timed to be temporally coincident with airborne electromagnetic (AEM) ice thickness measurements. Sea ice in the region surveyed was primarily composed of first year ice around 1.8 m thick, though multiyear ice was also observed and ice thicknesses >20m were measured over pressure ridges. P-band imagery disclosed a rich network of ridges with high brightness compared with X-band. Owing to the much greater penetration at P-band than X-band the volumetric decorrelation differs significantly between X-band and P-band that could be potentially exploited to improve ice-type classification. P-band penetration was assessed by simplistic differencing of the Xband and P-band digital elevation models (DEMs) after thresholding based on height error. Preliminary observations indicate surface penetration has been observed; however further analysis is required to determine the relationship between Xband-P-band elevation differences and ice penetration. Acquiring data from a lower altitude with improved SNR and enhanced interferometric sensitivity will benefit measurements.