FN Archimer Export Format PT J TI Storm waves focusing and steepening in the Agulhas current: Satellite observations and modeling BT AF QUILFEN, Yves YUROVSKAYA, M. CHAPRON, Bertrand ARDHUIN, Fabrice AS 1:1;2:2,3;3:1,3;4:4; FF 1:PDG-ODE-LOPS-SIAM;2:;3:PDG-ODE-LOPS-SIAM;4:; C1 Univ Brest, IFREMER, CNRS, IRD,LOPS, Brest, France. Marine Hydrophys Inst RAS, Sebastopol, Russia. Russian State Hydrometeorol Univ, St Petersburg, Russia. C2 IFREMER, FRANCE RUSSIAN ACAD SCI, RUSSIA UNIV RUSSIAN STATE HYDROMETEOROL, RUSSIA CNRS, FRANCE SI BREST SE PDG-ODE-LOPS-SIAM UM LOPS IN WOS Ifremer jusqu'en 2018 copubli-france copubli-int-hors-europe IF 8.218 TC 45 UR https://archimer.ifremer.fr/doc/00451/56289/57867.pdf LA English DT Article DE ;Extreme waves;Wave-current interactions;Satellite altimeter;SAR AB Strong ocean currents can modify the height and shape of ocean waves, possibly causing extreme sea states in particular conditions. The risk of extreme waves is a known hazard in the shipping routes crossing some of the main current systems. Modeling surface current interactions in standard wave numerical models is an active area of research that benefits from the increased availability and accuracy of satellite observations. We report a typical case of a swell system propagating in the Agulhas current, using wind and sea state measurements from several satellites, jointly with state of the art analytical and numerical modeling of wave-current interactions. In particular, Synthetic Aperture Radar and altimeter measurements are used to show the evolution of the swell train and resulting local extreme waves. A ray tracing analysis shows that the significant wave height variability at scales <~100 km is well associated with the current vorticity patterns. Predictions of the WAVEWATCH III numerical model in a version that accounts for wave-current interactions are consistent with observations, although their effects are still under-predicted in the present configuration. From altimeter measurements, very large significant wave height gradients are shown to be well captured, and also associated with the current vorticity patterns at global scale. PY 2018 PD OCT SO Remote Sensing Of Environment SN 0034-4257 PU Elsevier Science Inc VL 216 UT 000445990100039 BP 561 EP 571 DI 10.1016/j.rse.2018.07.020 ID 56289 ER EF