FN Archimer Export Format PT J TI On C-Band Quad-Polarized Synthetic Aperture Radar Properties of Ocean Surface Currents BT AF Fan, Shengren Kudryavtsev, Vladimir Zhang, Biao Perrie, William Chapron, Bertrand Mouche, Alexis AS 1:1;2:2,3;3:1,4;4:5;5:2,6;6:6; FF 1:;2:;3:;4:;5:PDG-ODE-LOPS-SIAM;6:PDG-ODE-LOPS-SIAM; C1 School of Marine Sciences, Nanjing University of Information Science & Technology, Nanjing 210044, China Russian State Hydrometerorological University, St. Petersburg 195196, Russia Marine Hydrophysical Institute, Sebastopol 299011, Russia Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai 519082, China Bedford Institute of Oceanography, Fisheries and Oceans Canada, Dartmouth, NS B2Y 4A2, Canada Laboratoire d’Océanographie Physique Spatiale, Ifremer, Brest 29200, France C2 UNIV NANJING, CHINA UNIV RUSSIAN STATE HYDROMETEOROL, RUSSIA MARINE HYDROPHYS INST, RUSSIA UNIV SUN YAT SEN, CHINA MPO BEDFORD INST OCEANOG, CANADA IFREMER, FRANCE SI BREST SE PDG-ODE-LOPS-SIAM UM LOPS IN WOS Ifremer UMR DOAJ copubli-int-hors-europe copubli-sud IF 2.1 TC 5 UR https://archimer.ifremer.fr/doc/00588/70030/67948.pdf LA English DT Article DE ;quad-polarized SAR;ocean surface current;polarization decomposition;Bragg scattering;breaking waves AB 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 PY 2019 PD OCT SO Remote Sensing SN 2072-4292 PU MDPI AG VL 11 IS 19 UT 000496827100135 DI 10.3390/rs11192321 ID 70030 ER EF