A Model for the Priestley-Taylor Parameter α

H. A. R. De Bruin Royal Netherlands Meteorological Institute, De Bilt, the Netherlands

Search for other papers by H. A. R. De Bruin in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

The behavior of the Priestley-Taylor parameter α is investigated using a simplified atmospheric boundary-layer model coupled to the Penman-Monteith equation. It is found that under conditions typical for a sunny summer day in the mid-latitudes, α is primarily determined by the surface resistance r3, (α ≈ 1.3 when r3 = 0, α ≈ 1 when r3 ≈ 60 s m−1, and α ≈ 0.6 when r3 ≈ 250 s m−1). This is in good agreement with, experimental values reported in literature. The model is an extension of the models by McNaughton (1976) and Perrier (1980).

Abstract

The behavior of the Priestley-Taylor parameter α is investigated using a simplified atmospheric boundary-layer model coupled to the Penman-Monteith equation. It is found that under conditions typical for a sunny summer day in the mid-latitudes, α is primarily determined by the surface resistance r3, (α ≈ 1.3 when r3 = 0, α ≈ 1 when r3 ≈ 60 s m−1, and α ≈ 0.6 when r3 ≈ 250 s m−1). This is in good agreement with, experimental values reported in literature. The model is an extension of the models by McNaughton (1976) and Perrier (1980).

Save