Abstract
Acoustic sounder and tower data obtained at the Boulder Atmospheric Observatory (BAO) are used to examine several features of the wave and turbulence structure associated with a disturbed nocturnal inversion. General features, including mean fields and Richardson number, for the case selected for this study are presented. Spectral analysis of the tower data reveals a separation of energy into wavelike and turbulent fluctuations. Analysis of the heat flux, however, shows upward counter-gradient fluxes in the vicinity of a low-level jet and near the top of the inversion. Cospectral analysis shows that the major contribution to the upward heat flux occurs at frequencies that would normally be considered characteristic of waves. In some cases, the upward flux is associated with a phase shift between vertical velocity w and fluctuating temperature θ different from the quadrature relation that would be expected of internal waves. Time series analysis reveals that these unexpected positive fluxes occur in relatively short bursts. Analysis of time series of θ and w in other cases, as well as inspection of acoustic sounder records, shows that sometimes such upward fluxes can result from a combination of wave motion and horizontal temperature advection. In this case the advection is associated with a shallow cold front.
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References
Atkinson, B. W.: 1981, Meso-Scale Atmospheric Circulations, Academic Press, New York, 495 pp.
Axford, D. N.: 1971, ‘Spectral Analysis of an Aircraft Observation of Gravity Waves’, Quart. J. Roy. Meteorol. Soc. 97, 313–321.
Caughey, S. J.: 1977, ‘Boundary-Layer Turbulence Spectra in Stable Conditions’, Boundary-Layer Meteorol. 11, 3–14.
Caughey, S. J. and Readings, C. J.: 1975, ‘An Observation of Waves and Turbulence in the Earth's Boundary Layer’, Boundary-Layer Meteorol. 9, 279–286.
Caughey, S. J., Wyngaard, J. C., and Kaimal, J. C.: 1979, ‘Turbulence in the Evolving Stable Boundary Layer’, J. Atmos. Sci. 36, 1041–1052.
Einaudi, F. and Finnigan, J. J.: 1981, ‘The Interaction Between an Internal Gravity Wave and the Planetary Boundary Layer, Part I: The Linear Analysis’, Quart. J. Roy. Meteorol. Soc. 107, 793–806.
Emmanuel, C. B., Bean, B. R., McAllister, L. G., and Pollard, J. R.: 1972, ‘Observations of Helmholtz Waves in the Lower Atmosphere with an Acoustic Sounder’, J. Atmos. Sci. 28, 886–892.
Gossard, E. E., Richter, J. H., and Atlas, D.: 1970, ‘Internal Waves in Atmosphere from High Resolution Radar Measurements’, J. Geophys. Res. 75, 903–913.
Kaimal, J. C.: 1973, ‘Turbulence Spectra, Length Scales, and Structure Parameters in the Stable Surface Layer’, Boundary-Layer Meteorol. 4, 289–309.
Kaimal, J. C. and Gaynor, J. E.: 1983, ‘The Boulder Atmospheric Observatory’, to appear in J. Appl. Meteorol.
Kaimal, J. C., Eversole, R. A., Lenshow, D. H., Stankov, B. B., Kahn, P. H., and Businger, J. A.: 1982, ‘Spectral Characteristics of the Convective Boundary Layer over Uneven Terrain’, J. Atmos. Sci. 39, 1098–1114.
Keliher, T. E.: 1975, ‘The Occurrence of Microbarograph-Detected Gravity Waves Compared with the Existence of Dynamically Unstable Wind Shear Layers’, J. Geophys. Res. 80, 2967–2976.
Merrill, J. T.: 1977, ‘Observational and Theoretical Study of Shear Instability in the Airflow near the Ground’, J. Atmos. Sci. 34, 911–921.
Neff, W. D.: 1980, ‘An Observational and Numerical Study of the Atmospheric Boundary Layer Overlying the East Antarctic Ice Sheet’, Ph.D. Thesis, University of Colorado, Boulder, Colo., 272 pp.
Stewart, R. W.: 1969, ‘Turbulence and Waves in a Stratified Atmosphere’, Radio Sci. 4, 1269–1278.
Turner, J. S.: 1973, Buoyancy Effects in Fluids, Cambridge University Press, Cambridge, U.K., 367 pp.
Wyngaard, J. C. and Coté, O. R.: 1972, ‘Cospectral Similarity in the Atmospheric Surface Layer’, Quart. J. Roy. Meteorol. Soc. 98, 590–603.
Zhou, Ming-yu, Lu, Nai-ping, and Qu, Shaohou: 1980, ‘Applications of Sodar Data in Weather Analysis and Local Weather Forecasting’, Kexue Tongbao 25, 328–331.
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Nai-Ping, L., Neff, W.D. & Kaimal, J.C. Wave and turbulence structure in a disturbed nocturnal inversion. Boundary-Layer Meteorol 26, 141–155 (1983). https://doi.org/10.1007/BF00121539
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DOI: https://doi.org/10.1007/BF00121539