A method for sea surface wind field retrieval from SAR image mode data

To retrieve wind field from SAR images, the development for surface wind field retrieval from SAR images based on the improvement of new inversion model is present. Geophysical Model Functions (GMFs) have been widely applied for wind field retrieval from SAR images. Among them CMOD4 has a good performance under low and moderate wind conditions. Although CMOD5 is developed recently with a more fundamental basis, it has ambiguity of wind speed and a shape gradient of normalized radar cross section under low wind speed condition. This study proposes a method of wind field retrieval from SAR image by combining CMOD5 and CMOD4 Five VV-polarisation RADARSAT2 SAR images are implemented for validation and the retrieval results by a combination method (CMOD5 and CMOD4) together with CMOD4 GMF are compared with QuikSCAT wind data. The root-mean-square error (RMSE) of wind speed is 0.75 m s−1 with correlation coefficient 0.84 using the combination method and the RMSE of wind speed is 1.01 m s−1 with correlation coefficient 0.72 using CMOD4 GMF alone for those cases. The proposed method can be applied to SAR image for avoiding the internal defect in CMOD5 under low wind speed condition.

[1]  T. Gerling.  Structure of the surface wind field from the Seasat SAR , 1986 .

[2]  W. Alpers,et al.  Atmospheric boundary layer rolls observed by the synthetic aperture radar aboard the ERS-1 satellite , 1994 .

[3]  D. Offiler.  The Calibration of ERS-1 Satellite Scatterometer Winds , 1994 .

[4]  S. Lehner,et al.  Mesoscale wind measurements using recalibrated ERS SAR images , 1998 .

[5]  Robert A. Shuchman,et al.  Wind vector retrieval using ERS-1 synthetic aperture radar imagery , 1996, IEEE Trans. Geosci. Remote. Sens..

[6]  David L. T. Anderson,et al.  Scatterometer Data Interpretation: Measurement Space and Inversion , 1997 .

[7]  David L. T. Anderson,et al.  Scatterometer data interpretation: Estimation and validation of the transfer function CMOD4 , 1997 .

[8]  Christopher C. Wackerman,et al.  Validating a scatterometer wind algorithm for ERS-1 SAR , 1998, IEEE Trans. Geosci. Remote. Sens..

[9]  K. Katsaros,et al.  Observation of tropical cyclones by high-resolution scatterometry , 1998 .

[10]  P. Vachon,et al.  Analysis of ERS-1/2 synthetic aperture radar wave mode imagettes , 1998 .

[11]  Pablo Clemente-Colon,et al.  Comparison of SAR-derived wind speed with model predictions and ocean buoy measurements , 2001, IEEE Trans. Geosci. Remote. Sens..

[12]  Marcos Portabella,et al.  Toward an optimal inversion method for synthetic aperture radar wind retrieval , 2002 .

[13]  Torsten Neubert,et al.  Seasonal variations of high‐latitude field‐aligned currents inferred from Ørsted and Magsat observations , 2002 .

[14]  Hans Hersbach,et al.  395 CMOD 5 An improved geophysical model function for ERS C-band scatterometry , 2003 .

[15]  Teruhisa Shimada,et al.  Wind jets and wind waves off the Pacific coast of northern Japan under winter monsoon captured by combined use of scatterometer, synthetic aperture radar, and altimeter , 2004 .

[16]  Wolfgang Koch,et al.  Directional analysis of SAR images aiming at wind direction , 2004, IEEE Transactions on Geoscience and Remote Sensing.

[17]  Jochen Horstmann,et al.  Ocean wind fields retrieved from the advanced synthetic aperture radar aboard ENVISAT , 2004 .

[18]  H. Graber,et al.  Can synthetic aperture radars be used to estimate hurricane force winds? , 2005 .

[19]  Yijun He,et al.  A new hurricane wind retrieval algorithm for SAR images , 2006 .

[20]  H. Hersbach,et al.  An improved C-band scatterometer ocean geophysical model function: CMOD5 , 2007 .

[21]  Johannes Schulz-Stellenfleth,et al.  Extreme wind conditions observed by satellite synthetic aperture radar in the North West Pacific , 2008 .

[22]  Q.‐H. Zhang,et al.  On the importance of interplanetary magnetic field B on polar cap patch formation , 2011 .

[23]  Yijun He,et al.  Wind speed retrieval from RADARSAT-2 quad-polarization images using a new polarization ratio model , 2011 .

[24]  Beichen Zhang,et al.  On the importance of interplanetary magnetic field ∣By∣ on polar cap patch formation , 2011 .