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Boundary-Layer Meteorology

, Volume 3, Issue 2, pp 178–190 | Cite as

Mean wind-direction shear through a forest canopy

  • F. B. Smith
  • D. J. Carson
  • H. R. Oliver
Article

Abstract

The equations of motion applying to the wind field in a forest canopy are simplified to a balance between the shearing stress gradient and either the form-drag of the leaves in the upper dense canopy, or the overall horizontal pressure gradient in the more open space beneath. The equations imply that, in descending through the forest, the stress and wind vectors turn through an angle which depends on the forest characteristics and on the stability and the speed of the airflow above the forest. The turning is roughly confirmed by an overall average measured on a very flat site near Thetford, Norfolk, covered by an extensive uniform pine forest.

Keywords

Shear Stress Pressure Gradient Open Space Wind Field Forest Canopy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© D. Reidel Publishing Company 1972

Authors and Affiliations

  • F. B. Smith
    • 1
  • D. J. Carson
    • 1
  • H. R. Oliver
    • 2
  1. 1.Meteorological Office (Boundary Layer Research Branch)BracknellEngland
  2. 2.Institute of HydrologyWallingfordEngland

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