Spaceborne radar remote sensing of ocean surfaces: electromagnetic modelling and applications

Spaceborne synthetic aperture radars are powerful tools for monitoring ocean surfaces. Various environmental conditions prevailing on the ocean surfaces strongly influence the quality of detection and monitoring using spaceborne imaging radars. In this paper, we discussed the electromagnetic modelling and applications of spaceborne polarimetric synthetic aperture radar for oil spill monitoring on ocean surface. Starting with the physics of electromagnetic wave scattering by ocean surfaces, we have introduced different concepts of polarimetric radar backscattering. These concepts are later used to develop different detection algorithms for enhanced identification of oil spills on ocean surfaces. We discussed two advanced schemes for post-processing fully polarimetric radar data for accurately detecting oil spills under varying ocean conditions. In doing so, we highlighted the challenges and advantages of single and half polarimetric spaceborne missions. Finally, we demonstrated how optimal combination of different channel information further improves the detection of oil spills and reduces false alarms.