Meteorology and Atmospheric Physics

, Volume 39, Issue 3–4, pp 197–202 | Cite as

Correlated humidity and temperature measurements in the urban atmospheric boundary layer

  • F. C. Medeiros Filho
  • D. A. R. Jayasuriya
  • R. S. Cole
  • C. G. Helmis
  • D. N. Asimakopoulos


To investigate the effect of atmospheric turbulence on microwave communication links, temperature and water vapor pressure have been measured and radio refractivity has been computed, during different meteorological conditions, in the atmospheric boundary layer of an urban site. The cospectra between temperature (T) and water vapor pressure (e) have been found to be either negative over the whole range of frequencies, or the low-frequency end of the cospectrum is of opposite sign relative to higher frequency end. In both cases cospectra follow a−5/3 law in the inertial subrange, in agreement with the theoretical predictions. The coherence spectra clearly show that the temperature and humidity fluctuations are highly coherent within the inertial subrange under both convective and stable conditions. The relative contribution ofC T 2 ,C eT andC e 2 to the real refractive index structure parameterC n 2 is examined and discussed.


Refractive Index Coherence Atmospheric Boundary Layer Index Structure Communication Link 
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  1. Asimakopoulos, D. N., Lalas, D. P., Helmis, C. G., Caroubalos, C. A., 1980: An atmospheric turbulence probe. IEEE Trans. on Geoscience and Remote Sensing GE-18, 347–353.Google Scholar
  2. Bean, B. R., Dutton, E. J., 1968:Radio Meteorology. New York: Dover Publications, 435 pp.Google Scholar
  3. Cole, R. S., Ho, K. L., Mavrokoukoulakis N. D., 1978: The effect of the outer scale of turbulence and wavelenght on scintillation fading at millimetre wavelenghts,IEEE Trans. Antenna propagation,26, 712–715.Google Scholar
  4. Fairall C. W., Schacher G. E., Davinson K. L., 1980: Measurements of the humidity structure function parametersC q2 andC Tq over the Ocean,Bound-Layer Meteor. 19, 81–92.Google Scholar
  5. Gjessing D. T., Kjelaas A. G., Golton E., 1973: Small-scale atmospheric structure deduced from measurements of temperature, humidity and refractive intex.Bound-Layer Meteor.,4, 475–492.Google Scholar
  6. Helmis, C. G. Asimakopoulos, D. N., Caroubalos, C. A., Cole, R. S., Medeiros Filho, F. C., Jayasuriya, D. A. R., 1983 a. A quantitative comparison of the refractive index structure parameter detemined from refractivity measurements and amplitude scintillation measurements at 36 GHz. IEEE Trans. on Geoscience and Remote Sensing, Vol. GE-21, No. 2, 221–224.Google Scholar
  7. Helmis, C. G., Asimakopoulos, D. N., Lalas, D. P., Moulsley, T. J., 1983b: On the local isotropy of the temperature field in an urban area.J. Climate Appl. Meteor.,22, 1594–1601.Google Scholar
  8. Helmis, C. G., Asimakopoulos, D. N., Cole, R. S., 1985: Low-level vertical velocity study using a high resolution sounder and comparison with direct measurements. IEEE Trans. on Geoscience and Remote sensing, GE 23, 164–170.Google Scholar
  9. Ho K. L., Mavrokoukoulakis N. D., Cole R. S., 1979: Propagation studies on the line-of-sight microwave link at 36 and 110 GHz.Microwave Optics and Acoustics,3, 93–98.Google Scholar
  10. Ippolito L. J., 1981: Radio propagation for space communications systems. Proceedings of the IEEE, Vol 69, 697–727.Google Scholar
  11. Kaimal J. C., Wyngaard J. C., Izumi Y., Coté O. R., 1972: Spectral characteristics of surface-layer turbulence.Quart. J. Roy. Meteor. Soc.,98, 563–589.Google Scholar
  12. Kaimal J. C., 1973: Turbulence spectra, length scales and structure parameters in the stable surface layer.Bound.-Layer Meteor.,4, 289–309.Google Scholar
  13. Kohsiek, W., 1982: Optical and in situ measuring of structure parameters relevant to temperature and humidity, and their application to the measuring of sensible and latent heat flux. NOAA Technical Memorandum ERL WPL-96.Google Scholar
  14. Lawrence R. S., Strohben J. W., 1970: A survey of clear-air propagation effects relevant to optical communications. Proc. of the IEEE, 58, 1523–1545.Google Scholar
  15. Little C. G., 1969: Acoustic methods for the remote probing of the lower atmosphere. Proceeding of the IEEE, Vol. 57, 571–578.Google Scholar
  16. McBean G. A., Elliot J. A., 1981: Pressure and humidity effects on optical refractive-index fluctuations.Bound.-Layer Meteor.,20, 101–109.Google Scholar
  17. McIlveen J. F. R., 1981: The potential importance of correlated Humidity and Temperature variations for atmospheric acoustic back-scatter.J. Appl. Meteor.,20, 206–209.Google Scholar
  18. Priestley J. T., Hill R. J., 1985: Measuring high-frequency humidity, temperature and radio refractive index in the surface layer.J. Atmos. Oceanic Technol.,2, 233–251.Google Scholar
  19. Wesely M. L., Alcaraz E. C., 1973: Diurnal cycles of the refractive index structure function coefficient.J. Geophys. Res.,78, 6224–6232.Google Scholar
  20. Wesely M. L., 1976: The combined effect of Temperature and Humidity fluctuations on Refractive index.J. Appl. Meteor.,15, 43–49.Google Scholar
  21. Wyngaard, J. C., Kaimal, J. C., Ochs, G. R., Hill, R. J., Sorensen, D. C., 1978a. An optical heat flux experiment Fourth Symposium on Meteorological Observations and Instrumentation, Apr. 10–14, Denver, Colo., publ by the Am. Met. Soc., 47–50.Google Scholar
  22. Wyngaard J. C., Pennell W. T., Lenschow D. H., LeMone M. A., 1978b: The temperature-humidity covariance budget in the convective boundary layer.J. Atmos. Sci.,35, 47–58.Google Scholar

Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • F. C. Medeiros Filho
    • 1
  • D. A. R. Jayasuriya
    • 1
  • R. S. Cole
    • 1
  • C. G. Helmis
    • 2
  • D. N. Asimakopoulos
    • 2
  1. 1.Department of Electronic and Electrical EngineeringUniversity College LondonLondonEngland
  2. 2.Department of Applied PhysicsUniversity of AthensAthensGreece

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