An Assessment of GEOS-3 Wave Height Measurements

  • Chester L. Parsons
Part of the Marine Science book series (MR, volume 8)


An iterative technique has been developed for the fitting of an averaged narrow-pulse radar altimeter return waveform from the Geodynamics Experimental Ocean Satellite (GEOS-3) with a four-parameter function derived from fundamental microwave rough scattering theory. For a signal reflected from the earth’s oceans, the parameter associated with the slope of the leading edge of this waveform is directly relatable to the significant wave height of the sea. The technique was used during February 1976 when an intensive effort was made to map the sea state of the North Atlantic Ocean for comparison with several forms of truth information. Underflights of GEOS-3 orbits were made by a NASA C-54 aircraft with other narrow pulse radar systems, and shipboard observations of the significant wave height were received from four European-staffed Ocean Weather Stations. More recently, comparisons of GEOS-3 measurements with NOAA Data Buoy Office data in the GuZf of Alaska have also been made. Excellent agreement exists between the aircraft remote sensor data, the buoy data, and the GEOS-3 measurements if the effect of tracking jitter is included in the GEOS-3 data processing. The average difference between the GEOS-3 measurements and the corresponding comparison data set values is shown to be.34 m with a standard deviation of the differences of.61 m. The agreement between satellite and Ocean Weather Ship data is not as good. The presence of systematic biases in the shipboard observations is suggested.


Wave Height Significant Wave Height Naval Research Laboratory Radar Altimeter Return Waveform 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Brown, G. S. 1977. The average impulse response of a rough surface and its applications, IEEE Trans. Antennas and Propagation, AP-25, 67–74.Google Scholar
  2. Rayne, G. S. 1977. Initial development of a method of significant waveheight estimation for GEOS-III, NASA CR-141425, pp. 11.Google Scholar
  3. Hughes Aircraft Company. 1976. Final report of the advanced application flight experiment breadboard pulse compression radar altimeter program. (FR–76–14–183, Hughes Aircraft Company; NASA Contract NAS6–2558) NASA CR–l41411.Google Scholar
  4. McCoogan, J. T. 1975. Satellite altimetry applications, IEEE Trans. Microwave Theory and Techniques, MIT-23, 970–978.Google Scholar
  5. Miller, L. S. and G. S. Brown. 1974. Engineering studies related to the GEOS-C radar altimeter, NASA CR-137462.Google Scholar
  6. Miller, L. S. and D. L. Hammond. 1972. Objectives and capabilities of the Skylab S-193 Altimeter Experiment, IEEE Trans. Geoscience Electronics, GE-10, 9, 711–722.Google Scholar
  7. Walsh, E. J. 1974. Analysis of experimental NRL radar altimeter data, Radio Science, 9, 711–722.CrossRefGoogle Scholar
  8. Walsh, E. J., E. A. Uliana, and B. S. Yaplee. 1977. Ocean wave heights measured by a high resolution pulse-limited radar altimeter, Boundary Layer Meteorology, 13, 187–200.Google Scholar
  9. Walsh, E. J. 1978. Extraction of ocean wave height from GEOS-3 altimeter data, submitted for publication to J. Geophys. Res.Google Scholar

Copyright information

© Plenum Press, New York 1979

Authors and Affiliations

  • Chester L. Parsons
    • 1
  1. 1.NASA Wallops Flight CenterWallops IslandUSA

Personalised recommendations