High Resolution Wind Field Retrieval from Synthetic Aperture Radar: North Sea Examples

  • J. Horstmann
  • W. Koch

A methodology for retrieving high resolution ocean surface wind fields from satellite borne Synthetic Aperture Radar (SAR) data is introduced and validated. The algorithm is applicable to SAR data acquired at C-band at moderate incidence angles. Wind directions are extracted from wind induced streaks that are visible in SAR images and that are very well aligned with the mean surface wind direction. To extract the orientation of these streaks an algorithm based on the derivation of local gradients is utilized. Ocean surface wind speeds are derived from the Normalized Radar Cross Section (NRCS) using a geophysical model function that describes the dependency of the NRCS on the wind and imaging geometry. To validate the algorithm and demonstrate its applicability, SAR retrieved wind fields of the North Sea are compared to numerical atmospheric model results of the German Weather Service.


Wind Speed Synthetic Aperture Radar Synthetic Aperture Radar Image Synthetic Aperture Radar Data Marine Atmospheric Boundary Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Dankert H, Horstmann J, Rosenthal W (2003) Ocean wind fields retrieved from radar-image sequences. J Geophys Res 108 (C11) doi:10.1029/2003JC002056Google Scholar
  2. Donnelly WJ, Carswell JR, McIntosh RE, Chang PS, Wilkerson J (1999) Revised ocean backscatter models at C and Ku band under high wind conditions. J Geophys Res, 104 (C5): 11485-11498CrossRefGoogle Scholar
  3. Etling D, Brown R (1993) Roll vortices in the planetary boundary layer: a review. Bound-Layer Meteorol 18 (3): 215-248CrossRefGoogle Scholar
  4. Gerling T (1986) Structure of the surface wind field from SEASAT SAR. J Geophys Res 91 (C2): 2308-2320CrossRefGoogle Scholar
  5. Hersbach H, Stoffelen A, de Haan S (2007) An improved C-band scatterometer ocean geophysical model function: CMOD5. J Geophys Res 112 (C3): C03006, doi 10.1029/2006JC003743CrossRefGoogle Scholar
  6. Horstmann J, Koch W, Lehner S, Tonboe R (2000) Wind retrieval over the ocean using synthetic aperture radar with C-band HH polarization. IEEE Trans Geosci Rem Sens 38 (5): 2122-2131CrossRefGoogle Scholar
  7. Horstmann J, Koch W, Lehner S, Tonboe R (2002) Ocean winds from RADARSAT-1 ScanSAR. Can J Rem Sens 28 (3): 524-533Google Scholar
  8. Horstmann J, Schiller H, Schulz-Stellenfleth J, Lehner S (2003) Global wind speed retrieval from SAR. IEEE Trans Geosci Rem Sens 41 (10): 2277-2286CrossRefGoogle Scholar
  9. Horstmann J, Koch W (2005) Measurement of Ocean Surface Winds Using Synthetic Aperture Radars. J Oceanic Eng 30 (3): 506-515Google Scholar
  10. Horstmann J, Thompson DR, Monaldo F, Iris S, Graber HC (2005) Can synthetic aperture radars be used to estimate hurricane force winds? Geophys Res Lett 32: L22801, doi:10.1029/2005GL023992CrossRefGoogle Scholar
  11. Johannessen OM, Alexandrov VY, Frolov IY, Sandven S, Pettersson LH, Bobylov LP, Kloster K, Smirnov VG, Mironov YU and Babich NG (2006) Remote Sensing of Sea Ice in the Northern Sea Route - Studies and Applications, Nansen Centers Polar Series no.4. Springer Praxis.Google Scholar
  12. Koch W (2004) Directional analysis of SAR images aiming at wind direction. IEEE Trans Geosci Rem Sens 42 (4): 702-710CrossRefGoogle Scholar
  13. Lehner S, Horstmann J, Koch W, Rosenthal W (1998) Mesoscale wind measurements using recalibrated ERS SAR images. J Geophys Res 103 (C4): 7847-7856CrossRefGoogle Scholar
  14. Monaldo F, Thompson D, Beal R, Pichel W, Clemente-Colon P (2001) Comparison of SAR-derived wind speed with model predictions and ocean buoy measurements. IEEE Trans Geosci Rem Sens 39 (12): 2587-2600CrossRefGoogle Scholar
  15. Monaldo F, Kerbaol V, Clemente-Colon P, Furevik B, Horstmann J, Johannessen J, Li X, Pichel W, Sikora T, Thompson D, Wackerman C (2004a) The SAR Measurement of Ocean Surface Winds: An Overview. Proc 2nd Workshop on Coastal and Marine Applications of SAR, ESA SP-Series SP-565, pp 15-32Google Scholar
  16. Monaldo F, Thompson D, Pichel W, Clemente-Colon P (2004b) A systematic comparison of QuikSCAT and SAR ocean surface wind speeds. IEEE Trans Geosi Rem Sens 42 (2): 283-291CrossRefGoogle Scholar
  17. Mouche A, Hauser D, Daloze JF, Guerin C (2005) Dual polarization measurements at C-band over the ocean: results from airborne radar observations and comparison with ENVISAT ASAR data. IEEE Trans Geosci Rem Sens 43 (4): 753-769CrossRefGoogle Scholar
  18. Quilfen Y, Chapron B, Elfouhaily T, Katsaros K, Tournadre J (1998) Observation of tropical cyclones by high-resolution scatterometry. J Geophys Res 103 (C4): 7767-7786CrossRefGoogle Scholar
  19. Stoffelen A, Anderson D (1997) Scatterometer data interpretation: Estimation and validation of the transfer function CMOD4. J Geophys Res 102 (C3): 5767-5780CrossRefGoogle Scholar
  20. Thompson D, Elfouhaily T, Chapron B (1998) Polarization ratio for microwave backscattering from the ocean surface at low to moderate incidence angles. Proc Int Geoscience and Remote Sensing Symp, Seattle, pp 1671-1673Google Scholar
  21. Thompson D, Beal R (2000) Mapping of mesoscale and submesoscale wind fields using synthetic aperture radar. John Hopkins APL Tech Dig 21 pp 58-67Google Scholar
  22. Unal C, Snoeij P, Swart P (1991) The polarization-dependent relation between radar backscatter from the ocean surface and surface wind vectors at frequencies between 1 and 18 GHz. IEEE Trans Geosci Rem Sens 29 (4): 621-626CrossRefGoogle Scholar
  23. Vachon PW, Dobson F (1996) Validation of wind vector retrieval from ERS-1 SAR images over the ocean. Global Atmos Ocean Syst 5: 177-187Google Scholar
  24. Vachon PW, Dobson F (2000) Wind retrieval from RADARSAT SAR images: Selection of a suitable C-band HH polarization wind retrieval model. Can J Rem Sens 26 (4): 306-313Google Scholar

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© Springer Science+Business Media B.V 2008

Authors and Affiliations

  • J. Horstmann
    • 1
  • W. Koch
    • 1
  1. 1.Institute of Coastal ResearchGKSS Research CenterGermany

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