Assessment of aerodynamic roughness via airborne radar observations

  • R. Greeley
  • L. Gaddis
  • N. Lancaster
  • A. Dobrovolskis
  • J. Iversen
  • K. Rasmussen
  • S. Saunders
  • J. van Zyl
  • S. Wall
  • H. Zebker
  • B. White
Part of the Acta Mechanica Supplementum book series (ACTA MECH.SUPP., volume 2)


The objective of this research is to assess the relationship among measurements of roughness parameters derived from radar backscatter, the wind, and topography on various natural surfaces and to understand the underlying physical causes for the relationship. This relationship will form the basis for developing a predictive equation to derive aerodynamic roughness (z0) from radar backscatter characteristics. Preliminary studies support the existence of such a relationship at the L-band (24 cm wavelength) direct polarization (HH) radar band frequencies. To increase the confidence in the preliminary correlation and to extend the application of the technique to future studies involving regional aeolian dynamics, the preliminary study has been expanded by: 1) defining the empirical relationship between radar backscatter and aerodynamic roughness of bare rocks and soils, 2) investigating the sensitivity of the relationship to microwave parameters using calibrated multiple wavelength, polarization, and incidence angle aircraft radar data, and 3) applying the results to models to gain an understanding of the physical properties which produce the relationship. The approach combines the measurement, analysis, and interpretation of radar data with field investigations of aeolian processes and topographic roughness.


Incidence Angle Radar Data Roughness Element Wind Profile Sand Transport 


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Copyright information

© Springer-Verlag Wien 1991

Authors and Affiliations

  • R. Greeley
    • 1
  • L. Gaddis
    • 1
  • N. Lancaster
    • 1
  • A. Dobrovolskis
    • 2
  • J. Iversen
    • 3
  • K. Rasmussen
    • 4
  • S. Saunders
    • 5
  • J. van Zyl
    • 5
  • S. Wall
    • 5
  • H. Zebker
    • 5
  • B. White
    • 6
  1. 1.Department of GeologyArizona State UniversityTempeUSA
  2. 2.National Aeronautics and Space AdministrationAmes Research CenterMoffett FieldUSA
  3. 3.Department of Aerospace EngineeringIowa State UniversityAmesUSA
  4. 4.Institute of GeologyAarhus UniversityAarhus CDenmark
  5. 5.Jet Propulsion LaboratoryPasadenaUSA
  6. 6.Department of Mechanical EngineeringUniversity of California at DavisDavisUSA

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