Editorial Type:
Article
Article Type:
Research Article

The Effect of Wind Shear and Curvature on the Gravity Wave Drag Produced by a Ridge

Miguel A. C. Teixeira Centro de Geofísica, and Department of Physics, University of Lisbon, Lisbon, Portugal

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Pedro M. A. Miranda Centro de Geofísica, and Department of Physics, University of Lisbon, Lisbon, Portugal

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Print Publication:
01 Nov 2004
DOI:
https://doi.org/10.1175/JAS3282.1
Page(s):
2638–2643
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Abstract

The analytical model proposed by Teixeira, Miranda, and Valente is modified to calculate the gravity wave drag exerted by a stratified flow over a 2D mountain ridge. The drag is found to be more strongly affected by the vertical variation of the background velocity than for an axisymmetric mountain. In the hydrostatic approximation, the corrections to the drag due to this effect do not depend on the detailed shape of the ridge as long as this is exactly 2D. Besides the drag, all the perturbed quantities of the flow at the surface, including the pressure, may be calculated analytically.

Corresponding author address: Miguel A. C. Teixeira, Centro de Geofísica da Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisbon, Portugal. Email: mateixeira@fc.ul.pt

Abstract

The analytical model proposed by Teixeira, Miranda, and Valente is modified to calculate the gravity wave drag exerted by a stratified flow over a 2D mountain ridge. The drag is found to be more strongly affected by the vertical variation of the background velocity than for an axisymmetric mountain. In the hydrostatic approximation, the corrections to the drag due to this effect do not depend on the detailed shape of the ridge as long as this is exactly 2D. Besides the drag, all the perturbed quantities of the flow at the surface, including the pressure, may be calculated analytically.

Corresponding author address: Miguel A. C. Teixeira, Centro de Geofísica da Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisbon, Portugal. Email: mateixeira@fc.ul.pt

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