Abstract
The characteristics of waves excited in a stratified shear flow with a velocity profile monotonically increasing above the ground are calculated numerically. It is shown that unstable modes exist when the Brunt-Väisälä frequency of the ambient atmosphere decreases sufficiently fast with height. Their growth rates as a function of the horizontal wavelength and the local Richardson number are given, and a comparison between them and experimental data obtained for the night-time-boundary layer of the Earth's atmosphere is carried out. Finally, the characteristics of the singular neutral modes that the system can support are presented.
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On a Fellowship from the National Research Council of Italy.
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Fua, D., Einaudi, F. & Lalas, D.P. The stability analysis of an inflexion-free velocity profile and its application to the night-time boundary layer in the atmosphere. Boundary-Layer Meteorol 10, 35–54 (1976). https://doi.org/10.1007/BF00218723
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DOI: https://doi.org/10.1007/BF00218723