Flux‐gradient relationships in the constant flux layer

Abstract An analysis is made of the Monin‐Obukhov function Φ M in the familiar wind profile equation, using data from two recent expeditions to Gurley (New South Wales) and Hay (New South Wales). In one, the friction velocity u * is determined directly by the eddy correlation method, and in the other, conducted during mid‐winter when small heat‐fluxes were experienced, by the use of a friction coefficient applied to a low‐level wind. By collating with a similar earlier analysis for heat and water vapour transfer, the variations of Φ M , Φ H and Φ W with stability are presented in tabular form in the z/L range − 0.01 to − 1.0. Within this range the empirical relationships Φ M = (1 − 16 z/L ) −1/4 and Φ H, W = (1 − 16 z/L ) −1/2 , and the implied equality between Ri and z/L , are found to approximate the data to within a few per cent.