Ocean Wave Parameters Retrieval from TerraSAR-X Images Validated against Buoy Measurements and Model Results

An ocean surface wave retrieval algorithm, Parameterized First-guess Spectrum Method (PFSM), which was initially developed for C-band Synthetic Aperture Radar (SAR), is modified to extract wave parameters from X-band TerraSAR-X (TS-X) images. Wave parameters, including significant wave height (SWH) and mean wave period (MWP) were extracted from nine TS-X HH-polarization images and were compared to in situ buoy measurements. The range of these wave retrievals is from 1 to 5 m of SWH and from 2 to 10 s of MWP. The retrieval accuracy could reach 80%. After that, a total of 16 collected TS-X HH-polarization images were used to invert wave parameters and then the retrieval results were compared to the operational WAVEWATCH-III wave model results. The SAR and in situ buoy wave comparison shows a 0.26 m Root-Mean-Square Error (RMSE) of SWH and a 19.8% of Scatter Index (SI). The SAR and WAVEWATCH-III model comparison yields slightly worse results with an RMSE of 0.43 m of SWH and a 32.8% of SI. For MWP, the SAR and buoy comparison shows the RMSE is 0.45 s with an SI of 26%, which is better than the results from the SAR and WAVEWATCH-III model comparison. Our results show that the PFSM algorithm is suitable to estimate wave parameters from X-band TS-X data.

[1]  Xiaoming Li,et al.  Ocean Wave Integral Parameter Measurements Using Envisat ASAR Wave Mode Data , 2011, IEEE Transactions on Geoscience and Remote Sensing.

[2]  T. Barnett,et al.  Measurements of wind-wave growth and swell decay during the Joint North Sea Wave Project (JONSWAP) , 1973 .

[3]  Luigi Cavaleri,et al.  Wave Modeling—Missing the Peaks , 2009 .

[4]  Sun Jian,et al.  Parameterized first-guess spectrum method for retrieving directional spectrum of swell-dominated waves and huge waves from SAR images , 2006 .

[5]  Susanne Lehner,et al.  Algorithm for Sea Surface Wind Retrieval From TerraSAR-X and TanDEM-X Data , 2014, IEEE Transactions on Geoscience and Remote Sensing.

[6]  F. Monaldo,et al.  Comparison of SIR‐C SAR wavenumber spectra with WAM model predictions , 1998 .

[7]  K. Hasselmann,et al.  On the nonlinear mapping of an ocean wave spectrum into a synthetic aperture radar image spectrum and its inversion , 1991 .

[8]  David Lyzenga,et al.  Comparison of radar and video observations of shallow water breaking waves , 2003, IEEE Trans. Geosci. Remote. Sens..

[9]  S. Hasselmann,et al.  Assimilation of wave spectra from pitch-and-roll buoys , 1997 .

[10]  Bertrand Chapron,et al.  A semiempirical model of the normalized radar cross section of the sea surface, 2. Radar modulation transfer function , 2003 .

[11]  C. Mastenbroek,et al.  A semiparametric algorithm to retrieve ocean wave spectra from synthetic aperture radar , 2000 .

[12]  W. Alpers,et al.  On the Relative Importance of Motion-Related Contributions to the SAR Imaging Mechanism of Ocean Surface Waves , 1986, IEEE Transactions on Geoscience and Remote Sensing.

[13]  W. Shao,et al.  Development of polarization ratio model for sea surface wind field retrieval from TerraSAR-X HH polarization data , 2014 .

[14]  Jian Sun,et al.  Retrieval of surface wave parameters from sar images and their validation in the coastal seas around Japan , 2009 .

[15]  Xiaofeng Li,et al.  Comparison of Ocean-Surface Winds Retrieved From QuikSCAT Scatterometer and Radarsat-1 SAR in Offshore Waters of the U.S. West Coast , 2011, IEEE Geoscience and Remote Sensing Letters.

[16]  S. Hasselmann,et al.  Computations and Parameterizations of the Nonlinear Energy Transfer in a Gravity-Wave Spectrum. Part I: A New Method for Efficient Computations of the Exact Nonlinear Transfer Integral , 1985 .

[17]  J. P. Hansen,et al.  High Range Resolution Radar Measurements of the Speed Distribution of Breaking Events in Wind-Generated Ocean Waves: Surface Impulse and Wave Energy Dissipation Rates , 2001 .

[18]  Roberto Udisti,et al.  Correction to “Evolution of chemical peak shapes in the Dome C, Antarctica, ice core” , 2007 .

[19]  William Perrie,et al.  Synergistic measurements of ocean winds and waves from SAR , 2015 .

[20]  Susanne Lehner,et al.  Coastal wave field extraction using TerraSAR-X data , 2013 .

[21]  Hendrik L. Tolman,et al.  A mosaic approach to wind wave modeling , 2008 .

[22]  Xiaoming Li,et al.  Investigation of Ocean Surface Wave Refraction Using TerraSAR-X Data , 2010, IEEE Transactions on Geoscience and Remote Sensing.

[23]  P. Heimbach,et al.  An improved algorithm for the retrieval of ocean wave spectra from synthetic aperture radar image spectra , 1996 .

[24]  S. Lehner,et al.  An empirical approach for the retrieval of integral ocean wave parameters from synthetic aperture radar data , 2007 .

[25]  Xiaofeng Li,et al.  Observation of hurricane-generated ocean swell refraction at the Gulf Stream north wall with the RADARSAT-1 synthetic aperture radar , 2002, IEEE Trans. Geosci. Remote. Sens..

[26]  M. He,et al.  An algorithm for the retrieval of sea surface wind fields using X-band TerraSAR-X data , 2012 .

[27]  Werner Alpers,et al.  The effect of orbital motions on synthetic aperture radar imagery of ocean waves , 1979 .

[28]  Jianhua Zhu,et al.  A semiempirical algorithm for SAR wave height retrieval and its validation using Envisat ASAR wave mode data , 2012, Acta Oceanologica Sinica.

[29]  Xiaofeng Li,et al.  A two-scale model to predict C-band VV and HH normalized radar cross section values over the ocean , 2002 .

[30]  S. Lehner,et al.  A parametric scheme for the retrieval of two-dimensional ocean wave spectra from synthetic aperture radar look cross spectra , 2005 .

[31]  Xiaofeng Li,et al.  Comparison of Ocean Surface Winds From ENVISAT ASAR, MetOp ASCAT Scatterometer, Buoy Measurements, and NOGAPS Model , 2011, IEEE Transactions on Geoscience and Remote Sensing.

[32]  D. Ross,et al.  On the detectability of ocean surface waves by real and synthetic aperture radar , 1981 .

[33]  Hui Lin,et al.  Assessment of an analytical model for sea surface wind speed retrieval from spaceborne SAR , 2010 .