Theoretical studies of the parameterization of the non-neutral surface boundary layer

Abstract

Viscous dissipation, as well as vertical flux divergences of turbulent energy and heat diffusion, are analyzed in the context of Monin-Obukhov similarity theory. The analysis employs a theoretical model which includes the budget equations of thermal and turbulent energy, the Weizäcker-Heisenberg relation, the Clarke-Delsol relations for wind shear, humidity and buoyant heat transport, as well as an improved scaling height relation specified in the text.

The trends of dissipation and turbulent transport, predicted by the model as functions ofz/L are in reasonable agreement with observed data in the stability range -1 ≦z/L ≦ 1; however, in very stable and in convective conditions, the predicted values cannot unambiguously be verified by means of observations. In addition, the theoretical model predicts that the vertical export of thermal energy by turbulent heat diffusion is significant in the budget of thermal energy both in stable and unstable conditions. As is to be expected, thermal energy is lost by diffusive heat export of the order of shear production in stable air, and of about the order of shear and buoyant production in unstable air.

In an added note, the momentum exchange coefficient associated with the model is discussed. The behaviour of this coefficient is consistent with the principal concepts of exchange in non-neutral air.