The PALSAR Polarimetric Mode for Sea Oil Slick Observation

Abstract

A study on sea oil slick observation by means of L-band polarimetric synthetic aperture radar (SAR) data is accomplished. It is based on different sea surface scattering mechanism expected with and without surface slicks. Polarimetric measurements are processed by means of a simple and very effective filtering technique which is electromagnetically based on the Mueller scattering matrix. Moreover, some polarimetric features, evaluated on both slick-free and slick-covered sea surfaces, are analyzed for confirming the filter output. Experiments are accomplished on the polarimetric SAR data acquired by the Phased Array-type L-band Synthetic Aperture Radar (PALSAR) sensor, mounted on board of the Advanced Land Observing Satellite (ALOS), and are relevant to oil slick, due to a tank accident, and look-alikes. Results demonstrate for the first time that L-band polarimetric SAR measurements are useful for oil slick observation purposes and witness the capability of the ALOS PALSAR data for such application

State of the art satellite and airborne marine oil spill remote sensing: Application to the BP Deepwater Horizon oil spill

“…Recent polarimetric radar satellite instruments have higher spatial resolution, aiding false positive discrimination, e.g., Envisat's ASAR with 30-m resolution which has a publically available Rapid Response Products, RADARSAT-2, with 3 to 100-m resolutions, and ALOS PALSAR with 7-m azimuthal resolution in high-resolution mode. In some cases, polarimetric SAR exhibits significantly different co-polarized signatures for slick-free and slick-covered sea surfaces, reducing some false positives (Migliaccio et al, 2009). …”

Recent Trend and Advance of Synthetic Aperture Radar with Selected Topics

“…Note, however, that L-band can also be used to extract the dark features as demonstrated using ALOS-PALSAR e.g., [360,361] (see also oil detection by L-band UAVSAR [362]). VV-polarization is preferred due to larger radar backscatter than HH-polarization from sea surface [351], yielding larger difference between the images of oil slicks and surrounding waters.…”

Polarimetric synthetic aperture radar utilized to track oil spills

“…With the advent of polarimetric SARs, new, effective, and automatic physical approaches have been conceived to locate and monitor oil spills [Gade et al, 1998;Migliaccio et al, 2011Migliaccio et al, , 2009aMigliaccio et al, , 2009bNunziata et al, 2011Nunziata et al, , 2010Nunziata et al, , 2008Velotto et al, 2011;Zhang et al, 2011]. These new approaches exploit the correlation characteristic between and among polarimetric signals when crude oil at sea is observed.…”

“…This is not the case for an oil-covered sea surface due to oil's heavy damping properties. This behavior has been successfully exploited in the development of simple and effective filtering techniques to observe oil at sea in dual-polarimetric SAR data [Migliaccio et al, , 2009a[Migliaccio et al, , 2009bVelotto et al, 2011]. When a fully polarimetric SAR is available, the hv or vh polarimetric signals can be used along with the hh and vv channels to develop techniques that are able to provide a simple and logical true or false output that limits uncertainties in interpretation [Migliaccio et al, , 2009bNunziata et al, 2011Nunziata et al, , 2008Zhang et al, 2011].…”