Boundary-Layer Meteorology

, Volume 19, Issue 1, pp 81–92 | Cite as

Measurements of the humidity structure function parameters, C q 2and C Tq , over the ocean

  • C. W. Fairall
  • G. E. Schacher
  • K. L. Davidson


Atmospheric turbulence measurements, including temperature and humidity fluctuations, were made from the R/V Acania off the coast of California in June, 1979. The purpose of the experiment was to investigate the scaling properties of the humidity structure function parameter (Cq2) and temperaturehumidity cospectrum structure parameter (CTq) in the marine surface layer. The bulk parameterization method was used to obtain Monin-Obukhov Similarity (MOS) scaling parameters u*, T*, q*and L. Assuming a neutral stability humidity drag coefficient cqn = 1.3 × 10-3the dimensionless humidity structure function parameter Cq2Z2/3/q*2was found to be 18% lower than the corresponding temperature function obtained by Wyngaard et al. (1971). Furthermore, the measurements indicate that the temperature-humidity fluctuations are highly coherent well into the inertial subrange. The results have direct application to turbulent scattering of waves propagating in the atmosphere (particularly microwaves) and methods of estimating air-sea surface fluxes.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Buck, Arden: 1979, ‘RSF/RAF Lyman-alpha Hydrometer Model LA-3’, Operating and Maintenance Manual 083–032–007, NCAR, Boulder, Co.Google Scholar
  2. Businger, J. A.: 1973, ‘Turbulent Transfer in the Atmospheric Surface Layer’, Workshop on Micrometeorology, D. Haugen, Editor, American Meteorological Society, 67–98.Google Scholar
  3. Davidson, K. L., Houlihan, T. M., Fairall, C. W., and Schacher, G. E.: 1978, ‘Observation of the Temperature Structure Function Parameter, C T 2, Over the Ocean’, Boundary-Layer Meteorol., 15, 507–523.Google Scholar
  4. Fairall, C. W., Davidson, K. L., and Schacher, G. E.: 1979, ‘Humidity Effects and Sea-Salt Contamination of Atmospheric Temperature Sensors’, J. Appl. Meteorol. to be published.Google Scholar
  5. Friehe, C. A., La Rue, J. C., Champagne, F. H., Gibson, C. H., and Dreyer, G. F.: 1975, ‘Effects of Temperature and Humidity Fluctuations on the Optical Refractive Index in the Marine Boundary Layer’, J. Opt. Soc. Amer., 65, 1502–1511.Google Scholar
  6. Friehe, C. A.: 1977, ‘Estimation of the Refractive-Index Temperature Structure Parameter in the Atmosphere Boundary Layer Over the Ocean’, Appl. Optics, 16, 334–340.Google Scholar
  7. Friehe, C. A. and Schmitt, K. F.: 1976, ‘Parameterization of Air-Sea Interface Fluxes of Sensible Heat and Moisture by the Bulk Aerodynamic Formulas’, J. Phys. Oceanogr., 6, 801–809.Google Scholar
  8. Haugen, D.: 1973, Workshop on Micrometeorology, American Meteorological Society [Science Press] 392 pp.Google Scholar
  9. Kondo, J.: 1975, ‘Air-Sea Bulk Transfer Coefficients in Diabatic Conditions’, Boundary-Layer Meteorol., 6, 47–52.Google Scholar
  10. Liu, W. T.: 1978, ‘The Molecular Effects on Air-Sea Exchanges’, Ph. D. Dissertation, University of Washington, Seattle, Wa, 170 pp.Google Scholar
  11. McBean, G. A. and Miyake, M.: 1972, ‘Turbulent Transfer Mechanisms in the Atmospheric Surface Layer’, Quart. J. Roy., Meteorol Soc., 98, 383–398.Google Scholar
  12. Shutt, W. L.: 1976, ‘An Investigation of Small Scale Humidity Fluctuations in the Marine Boundary Layer’, M.S. Thesis, Naval Postgraduate School, Monterey, CA, 63 pp.Google Scholar
  13. Schmitt, K. F., Friehe, C. A., and Gibson, C. H.: 1978, ‘Humidity Sensitivity of Atmospheric Temperature Sensors by Salt Contamination’, J. Phys. Oceanogr., 8, 151–161.Google Scholar
  14. Tatarskii, V. I.: 1971, ‘The Effects of The Turbulent Atmosphere on Wave Propagation’ [NTIS TT 68-50464].Google Scholar
  15. Wesely, M. L.: 1976a, ‘The Combined Effects of Temperature and Humidity Fluctuations on Refractive Index’, J. Appl. Meteorol., 15, 43–49.Google Scholar
  16. Wesely, M. L.: 1976b, ‘A Comparison of Two Optical Methods for Measuring Line Averages of Thermal Exchanges Above Warm Water Surfaces’, J. Appl. Meteorol., 15, 1177–1188.Google Scholar
  17. Wesely, M. L. and Hicks, B. B.: 1978, ‘High Frequency Temperature and Humidity Correlation Above a Warm Wet Surface’, J. Appl. Meteorol., 17, 123–128.Google Scholar
  18. Wyngaard, J. C., Izumi, Y., and Collins, S. A.: 1971, ‘Behavior of the Refractive Index Structure Parameter near the Ground’, J. Opt. Soc. Am., 61, 1646–1650.Google Scholar
  19. Wyngaard, J. C., Pennell, W. T., Lenschow, D. H., and LeMone, M. S.: 1978, ‘The Temperature-Humidity Covariance Budget in the Convective Boundary Layer’, J. Atmos. Sci., 35, 47–58.Google Scholar
  20. Wyngaard, J. C. and Clifford, S. F.: 1978, ‘Estimating Momentum, Heat and Moisture Fluxes From Structure Parameters’, J. Atmos. Sci., 35, 1204–1211.Google Scholar

Copyright information

© D. Reidel Publishing Co 1980

Authors and Affiliations

  • C. W. Fairall
    • 1
  • G. E. Schacher
    • 1
  • K. L. Davidson
    • 1
  1. 1.Environmental Physics GroupNaval Postgraduate SchoolMontereyUSA

Personalised recommendations