All-Season Compact-Polarimetry C-band SAR Observations of Sea Ice

Compact-polarimetry (CP) synthetic aperture radar (SAR) observations are presented for major sea ice types in each ice season. CP data for three wide-swath Radarsat Constellation Mission (RCM) modes were simulated and evaluated. Regression models and statistical distances as functions of incidence angles were calculated for 26 CP parameters, based on 969 samples of user-selected homogeneous regions of sea ice. CP parameters, best able to discriminate sea ice types and open water, were quantitatively identified in three incidence angle ranges (19-29 degrees, 30-39 degrees, 40-49 degrees). These parameters will likely provide discrimination of sea ice types and open water for both visual interpretation and automated classification. Several parameter-ice type combinations exhibit novel scattering responses, which present new opportunities for ice type discrimination and for inferring scattering mechanisms. Specifically, phase-related parameters with early-stage ice types provide discrimination for ice type pairings that are difficult with co- or dual-polarized data. CP parameters change with incidence angle, which necessitates the use of certain CP parameters at smaller incidence angles and others at larger incidence angles in wide-swath RCM modes. The Canadian Ice Service will implement CP SAR data in their operational workflows once the RCM is operational. Prelaunch study results provide a valuable resource for early adoption of CP data.