Boundary-Layer Meteorology

, Volume 2, Issue 4, pp 466–475 | Cite as

Average Bowen-ratio methods of calculating evapotranspiration applied to a Douglas fir forest

  • T. A. Black
  • K. G. McNaughton


Daily evapotranspiration from a Douglas fir forest was calculated using Webb's average Bowen-ratio method. Webb's method is generalized to include the effects of the diabatic wind profile. Over a 17-day period characterized by light winds, the modified Webb method agreed with the daily totals of half-hour energy balance calculations to within 1 1/2 % on the average, while Webb's method overestimated by 26 % on the average.


Energy Balance Wind Profile Balance Calculation Daily Total Light Wind 
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Copyright information

© D. Reidel Publishing Company 1972

Authors and Affiliations

  • T. A. Black
    • 1
  • K. G. McNaughton
    • 1
  1. 1.Dept. of Soil ScienceUniversity of British ColumbiaVancouverCanada

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