Atmospheric waveguide

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An atmospheric waveguide is an atmospheric flow feature that improves the propagation of certain atmospheric waves. [1]

The effect arises because wave parameters such as group velocity or vertical wavenumber depend on mean flow direction and strength. Thus, for instance, westerlies might be a good waveguide for eastward-traveling waves, but might strongly dissipate westward-traveling waves, by increasing or decreasing their vertical wavenumber, respectively. Modification of the waves' group velocity will change their meridional propagation speed, directing them more polewards or more equatorwards.

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References

  1. Chunchuzov, Igor P. (July 1, 1996). "The Spectrum of High-Frequency Internal Waves in the Atmospheric Waveguide". Journal of the Atmospheric Sciences . 53 (13): 1798–1814. Bibcode:1996JAtS...53.1798C. doi: 10.1175/1520-0469(1996)053<1798:TSOHFI>2.0.CO;2 .