Abstract
A turbulence closure model for atmospheric boundary layers is examined, under the assumption that the turbulent flow is steady in its ensemble average and the advection and diffusion terms in the turbulent Reynolds stress and heat flux equations are neglected. The constants which are introduced in order to obtain a closure system are determined referring the experimental results obtained in the wind tunnel. The validity of the closure model thus obtained is checked referring the observational results obtained in the constant-flux layer. In order to apply our model to the planetary boundary layer, simple forms for the eddy transport coefficients of momentum and heat are formulated. In this case the parametarization of the scale-length l=l(z) (z: heihgt) which is introduced in estimating the dissipation rate of turbulent kinetic energy with height is discussed in order to satisfy the observational result.
