Baroclinic flow over a mountain ridge

Peter R. Bannon, J. A. Zehnder

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

If the Rossby number squared is small, the equation for the vertical displacement of a fluid parcel is elliptic if there is forward shear (wind increasing with height) or weak backward shear (wind decreasing with height) but hyperbolic if there is strong backward shear such that the incident wave vanishes at some level in the flow. Steady-state results indicate that forward shear weakens the cold-core geostrophic mountain anticyclone predicted by barotropic theory while weak backshear strengthens it. This behaviour arises from the warm-(cold-) air advection in the forward (backward) shear case. While the total ageostrophic flux of mass across the mountain peak is greater for the forward shear case, the maximum ageostrophic cross-mountain wind is less. -from Authors

Original languageEnglish (US)
Pages (from-to)703-714
Number of pages12
JournalJournal of the Atmospheric Sciences
Volume46
Issue number5
DOIs
StatePublished - Jan 1 1989

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baroclinic motion
mountain
wind shear
Rossby number
anticyclone
cold air
advection
fluid

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

Cite this

Bannon, Peter R. ; Zehnder, J. A. / Baroclinic flow over a mountain ridge. In: Journal of the Atmospheric Sciences. 1989 ; Vol. 46, No. 5. pp. 703-714.
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Baroclinic flow over a mountain ridge. / Bannon, Peter R.; Zehnder, J. A.

In: Journal of the Atmospheric Sciences, Vol. 46, No. 5, 01.01.1989, p. 703-714.

Research output: Contribution to journalArticle

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