Encyclopedia of Remote Sensing

2014 Edition
| Editors: Eni G. Njoku

SAR-Based Bathymetry

  • Han Wensink
  • Werner Alpers
Reference work entry
DOI: https://doi.org/10.1007/978-0-387-36699-9_207


Retrieval of underwater bottom topography by using synthetic aperture radar (SAR)


Synthetic aperture radar (SAR) is an active instrument which yields high-resolution images in the microwave frequency band. When applied to image the ocean, it detects small variations in the small-scale sea surface roughness. These roughness variations can result, for example, from variations in surface current speed caused by a tidal flow over shallow sandbanks. Although the microwaves cannot penetrate into the water body, SAR can retrieve information on underwater bottom topography (or bathymetry) indirectly by measuring variations in the small-scale sea surface roughness.


Underwater bottom topographic features, such as sandbanks and ridges, become visible on radar images of the sea surface only when there is a current present (usually a tidal current) which flows over them. This causes local perturbations to the current which in turn modulates the sea surface...

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  1. Alpers, W., and Hennings, I., 1984. A theory of the imaging mechanism of underwater bottom topography by real and synthetic aperture radar. Journal of Geophysical Research, 89, 10529–10546.CrossRefGoogle Scholar
  2. Calkoen, C. J., Hesselmans, G. H. F. M., Wensink, G. J., and Vogelzang, J., 2001. The bathymetry assessment system: efficient depth mapping in shallow seas using radar images. International Journal of Remote Sensing, 22, 2973–2998.CrossRefGoogle Scholar
  3. Romeiser, R., and Alpers, W., 1997. An improved composite surface model for the radar backscattering cross section of the ocean surface, 2. Model response to surface roughness variations and the radar imaging of underwater bottom topography. Journal of Geophysical Research, 102, 25251–25267.CrossRefGoogle Scholar
  4. Shuchman, R. A., Lyzenga, D. R., and Meadows, G. A., 1985. Synthetic aperture radar imaging of ocean-bottom topography via tidal-current interactions: theory and observations. International Journal of Remote Sensing, 6, 1179–1200.CrossRefGoogle Scholar
  5. Vogelzang, J., 1997. Mapping submarine sand waves with multi-band imaging radar, 1. Model development and sensitivity analysis. Journal of Geophysical Research, 102, 1163–1181.CrossRefGoogle Scholar
  6. Wensink, H., and Campbell, G., 1997. Bathymetric map production using the ERS SAR. Backscatter, 8, 17–22.Google Scholar

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Han Wensink
    • 1
  • Werner Alpers
    • 2
  1. 1.ARGOSS BVVollenhoveThe Netherlands
  2. 2.Institute of OceanographyUniversity of HamburgHamburgGhana