Oil Slick Characterization Using Radarsat Constellation Mission Simulated Data

Abstract

The forthcoming RADARSAT Constellation Mission (RCM) will have Compact Polarimetry (CP) modes. A key advantage of CP is that these modes provide more polarimetric information than dual-polarized RADARSAT-2 with no reduction in swath width. To investigate the performance of CP for oil slick characterization, the RCM SC50 and the LNSC modes were simulated from a 10 m resolution RADARSAT-2 Fine quad polarized image. The SC50 and the LNSC had the same 350 km swath width, but differed in resolution, 50 m for SC50 versus 100 m for LNSC, and noise floor, -22 dB for SC50 versus -25 dB for LNSC. There was good visual discrimination between the slick and the ocean for both SC50 and LNSC which was attributed to the ~ 6 dB difference between oil and ocean for RH backscatter. As the resolution went from 10 m to 50 m and then 100 m, the ocean-oil boundary became progressively less well-defined. Therefore, the use of the 50 m SC50 mode versus the 100 m resolution LNSC mode may be a better choice for slick detection, unless there is a need to extract polarimetric information from the -25 dB NESZ LNSC versus the – 22 dB NESZ SC50. The Degree of Polarization (DoP) for both SC50 and LNSC was similar to the DoP calculated from the RADARSAT-2 quad polarized image, thus suggesting that oil slick characterization, specifically the discrimination of sheen and emulsion might be possible with CP imagery.