Title
On C-Band Quad-Polarized Synthetic Aperture Radar Properties of Ocean Surface Currents.
Abstract
We present new results for ocean surface current signatures in dual co- and cross-polarized synthetic aperture radar (SAR) images. C-band RADARSAT-2 quad-polarized SAR ocean scenes are decomposed into resonant Bragg scattering from regular (non-breaking) surface waves and scattering from breaking waves. Surface current signatures in dual co- and cross-polarized SAR images are confirmed to be governed by the modulations due to wave breaking. Due to their small relaxation scale, short Bragg waves are almost insensitive to surface currents. Remarkably, the contrast in sensitivity of the non-polarized contribution to dual co-polarized signals is found to largely exceed, by a factor of about 3, the contrast in sensitivity of the corresponding cross-polarized signals. A possible reason for this result is the co- and cross-polarized distinct scattering mechanisms from breaking waves: for the former, quasi-specular radar returns are dominant, whereas for the latter, quasi-resonant scattering from the rough breaking crests governs the backscatter intensity. Thus, the differing sensitivity can be related to distinct spectral intervals of breaking waves contributing to co- and cross-polarized scattering in the presence of surface currents. Accordingly, routinely observed current signatures in quad-polarized SAR images essentially originate from wave breaking modulations, and polarized contrasts can therefore help quantitatively retrieve the strength of surface current gradients.
Year
DOI
Venue
2019
10.3390/rs11192321
REMOTE SENSING
Keywords
Field
DocType
quad-polarized SAR,ocean surface current,polarization decomposition,Bragg scattering,breaking waves
C band,Synthetic aperture radar,Remote sensing,Ocean current,Geology
Journal
Volume
Issue
Citations 
11
19
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Shengren Fan101.01
Vladimir N. Kudryavtsev202.03
Biao Zhang39723.66
William Perrie410527.21
Bertrand Chapron524452.89
Alexis Mouche68521.13