Critical levels in a vertically rotating compressible atmosphere

I. A. Eltayeb, P. Kandaswamy

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The propagation properties of gravity waves in a vertically rotating compressible vertically sheared zonal flow are investigated. In slowly-varying shear flows the local dispersion relation is used to study the wave-normal surfaces and the possible types of ray trajectory. It is found that the relaxation of the Boussinesq approximation modifies the two critical levels present in the Boussinesq fluid in such a way that waves approaching them can exhibit valve-like behaviour. However, in a full wave treatment the valve behaviour, already known to be effected by variations in the basic state, is here modified by the neglect of the Boussinesq approximation. The influence of compressibility is shown to increase the number of singularities by two. The wave invariant of the system (which represents conservation of the vertical total wave-energy flux) is used to examine the influence of the singularities on the vertical propagation of the waves, and to conclude that energy absorption can only occur at the singularities present in a slowly varying basic state in an incompressible Boussinesq fluid.

Original languageEnglish
Pages (from-to)313-330
Number of pages18
JournalQuarterly Journal of Mechanics and Applied Mathematics
Volume32
Issue number3
DOIs
Publication statusPublished - Aug 1979

Fingerprint

Gravitation
Atmosphere
Rotating
atmospheres
Boussinesq approximation
Boussinesq Approximation
Singularity
Vertical
Propagation
Fluid
Energy Absorption
Normal Surface
Gravity Waves
Fluids
Gravity waves
propagation
fluids
energy absorption
Energy absorption
Compressibility

ASJC Scopus subject areas

  • Molecular Biology
  • Statistics and Probability
  • Computational Mathematics
  • Condensed Matter Physics
  • Applied Mathematics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Critical levels in a vertically rotating compressible atmosphere. / Eltayeb, I. A.; Kandaswamy, P.

In: Quarterly Journal of Mechanics and Applied Mathematics, Vol. 32, No. 3, 08.1979, p. 313-330.

Research output: Contribution to journalArticle

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