FN Archimer Export Format PT J TI Measuring ocean waves in sea ice using SAR imagery: A quasi-deterministic approach evaluated with Sentinel-1 and in situ data BT AF ARDHUIN, Fabrice STOPA, Justin CHAPRON, Bertrand COLLARD, Fabrice SMITH, Madison THOMSON, Jim DOBLE, Martin BLOMQUIST, Byron PERSSON, Ola COLLINS, Clarence O., III WADHAMS, Peter AS 1:1;2:2,9;3:9;4:3;5:4;6:4;7:5;8:6;9:6;10:7;11:8; FF 1:;2:PDG-ODE-LOPS-SIAM;3:PDG-ODE-LOPS-SIAM;4:;5:;6:;7:;8:;9:;10:;11:; C1 Univ Brest, CNRS, IRD, IFREMER,LOPS,IUEM, Brest, France. Ecole Cent Nantes, LHEEA, Nantes, France. OceanDataLab, Brest, France. Univ Washington, Seattle, WA 98195 USA. PolarScientific Ltd, Appin, England. Univ Colorado, NOAA, Earth Syst Res Lab, CIRES, Boulder, CO 80309 USA. Naval Res Lab, Oceanog Div, Stennis Space Ctr, MS USA. Cambridge Polar Consultants Ltd, Cambridge, England. C2 CNRS, FRANCE ECOLE CENT NANTES, FRANCE OCEANDATALAB, FRANCE UNIV WASHINGTON, USA POLARSCIENTIFIC LTD, UK NOAA, USA NAVAL RES LAB, USA CAMBRIDGE POLAR CONSULTANTS LTD, UK IFREMER, FRANCE SI BREST SE PDG-ODE-LOPS-SIAM UM LOPS IN WOS Ifremer jusqu'en 2018 copubli-france copubli-europe copubli-int-hors-europe IF 6.457 TC 49 UR https://archimer.ifremer.fr/doc/00361/47214/47451.pdf LA English DT Article DE ;SAR;Sentinel-1A;Ocean waves;Sea ice AB Measurements of wave heights in marginal ice zones are limited to very few in situ data. Here we revisit the linear and quasilinear theories of Synthetic Aperture Radar imaging of waves in the particular case of waves in sea ice. Instead of only working with spectra, we have developed an iterative nonlinear algorithm to estimate phase-resolved deterministic maps of wave-induced orbital velocities, from which elevation spectra can be derived. Application of this algorithm to Sentinel 1A wave mode images in the Southern Ocean shows that it produces reasonable results for swells in all directions except when they propagate at a few degrees off the range direction. The estimate of wave parameters is expected to work best when the shortest wave components, those which cause a pixel displacement of the order of the dominant wavelength in azimuth, can be neglected. Otherwise short waves produce a blurring of the image, increasing exponentially with the azimuthal wavenumber and reducing the estimated wave amplitude. Given the expected spatial attenuation of waves in ice-covered regions, our deterministic method should apply beyond a few tens of kilometers in the ice, without any correction for short wave effects. In situ data collected around the ice edge as part of the 2015 SeaState DRI cruise in the Beaufort confirm the progressive image blurring caused by such short waves, and the apparent reduction in the wave modulation. When short waves propagate from the open ocean towards the ice, this blurring can produce an unrealistic apparent increase of wave height, from the open ocean up to a few tens of kilometers inside the ice. PY 2017 PD FEB SO Remote Sensing Of Environment SN 0034-4257 PU Elsevier Science Inc VL 189 UT 000393005400016 BP 211 EP 222 DI 10.1016/j.rse.2016.11.024 ID 47214 ER EF