Boundary-Layer Meteorology

, Volume 7, Issue 4, pp 501–512 | Cite as

Mountain effect on the motion in the atmosphere's boundary layer

  • S. K. Kao
  • J. N. Paegle
  • W. E. Normington
Article

Abstract

An analysis of 3 years' (1967–70) radiosonde wind data on the windward (Salt Lake City, Utah) and lee (Denver, Colorado) sides of mountains indicates that at these two stations: (1) the distributions of the kinetic energy of the mean and turbulent motions are similar above the mountain top; (2) below the mountain top, on the windward side, mountains tend to divert the component of the mean motion normal to the mountains to that parallel to the mountains; (3) the meridional eddy transport of westerly momentum is affected by the presence of the mountains to a higher level to the lee of the mountains than upwind of them; (4) the production of turbulent energy is higher below the mountain top in the vicinity of mountains than it is for the zonal average; (5) high frequencies of the motion show a more pronounced contribution in the meridional motion in the windward side, but in the zonal motion in the lee of the mountains; (6) disturbances of 1–2 day periods can be maintained deep into the valley, whereas disturbances of longer periods reduce their amplitudes rapidly with decreasing height from the mountain top; (7) the cospectra of the wind velocities show that the southward/northward transport of westerly momentum results from a southward/northward contribution from most frequencies. The main contributions come from eddies with periods longer than two days.

Keywords

Atmosphere Boundary Layer Mountain Effect 

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Copyright information

© D. Reidel Publishing Company 1974

Authors and Affiliations

  • S. K. Kao
    • 1
  • J. N. Paegle
    • 1
  • W. E. Normington
    • 1
  1. 1.University of UtahSalt Lake CityUSA

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