FN Archimer Export Format
PT J
TI Assessment of ocean wave spectrum using global Envisat/ASAR data and hindcast simulation
BT 
AF Li, Huimin
   Stopa, Justin
   Mouche, Alexis
   Zhang, Biao
   He, Yijun
   Chapron, Bertrand
AS 1:1,3;2:2;3:3;4:1;5:1;6:3;
FF 1:PDG-ODE-LOPS-SIAM;2:;3:PDG-ODE-LOPS-SIAM;4:;5:;6:PDG-ODE-LOPS-SIAM;
C1 School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, China
   Department of Ocean and Resources Engineering, University of Hawaii at Manoa, Honolulu, HI, USA
   Ifremer, Univ. Brest, CNRS, IRD, Laboratoire d'Océanographie Physique et Spatiale (LOPS), IUEM, Brest, France
C2 UNIV NANJING, CHINA
   UNIV HAWAII MANOA, USA
   IFREMER, FRANCE
SI BREST
SE PDG-ODE-LOPS-SIAM
UM LOPS
IN WOS Ifremer UMR
   copubli-int-hors-europe
   copubli-sud
IF 13.85
TC 5
UR https://archimer.ifremer.fr/doc/00709/82117/88698.pdf
LA English
DT Article
DE ;Envisat/ASAR wave mode observations;SAR image spectral parameter;Spectral assessment
AB Wave mode of spaceborne synthetic aperture radar (SAR) is designed for the global ocean wave observations. Despite the fact that the significant wave height inferred from SAR measurements has been validated against model output and in-situ data, SAR's primary and unique capability for operational 2-dimensional spectral description of sea state remains to be fully evaluated. In this study, we extended the previous assessment approaches by introducing a new SAR image spectral parameter, the Mean rAnge Cross-Spectrum (MACS) that focuses on the isolated wave scales along the radar line-of-sight direction. MACS is an efficient variable in that it characterizes the local wave spectra properties without need of the non-linear wave inversion procedure. The assessment is based on the multiple-year data acquired by Envisat/ASAR wave mode, along with the collocated WaveWatch III (WW3) hindcast and the in-situ buoy-observed wave spectra, for which the SAR forward transformation is systematically performed to obtain the simulated image spectra. Inter-comparison between SAR-measured and WW3-simulated MACS demonstrates that the consistency is wavelength (or wavenumber) dependent. Three typical wavelengths, around 62 m for windsea, 168 m for intermediate waves and 342 m for swell, are selected to present the MACS comparison in detail. Comparable magnitude of SAR-measured and the simulated MACS is observed for the intermediate waves and swell, while larger simulation values are predicted for the windsea waves. Spatial distribution of MACS agrees well between these two data sets for all wavelengths with high correlation coefficients (>0.8) in most of the global ocean. One exception is in the extratropics where the quantitative difference is particularly notable. In the contrary, when comparing SAR-measured and buoys-simulated MACS, the agreement increases towards the shorter (<100 m) wavelengths. We also found that the large-scale atmospheric/oceanic features persistent on SAR images lead to the overestimate of SAR MACS at long wavelengths, which is expected to bias the wave inversion. The wave spectra retrieval performance shall advance as long as such impact is properly resolved. 
PY 2021
PD OCT
SO Remote Sensing Of Environment
SN 0034-4257
PU Elsevier BV
VL 264
UT 000688410600002
DI 10.1016/j.rse.2021.112614
ID 82117
ER

EF