A Practical Integral Closure Model for Mean Vertical Transport of a Scalar in a Convective Boundary Layer

Abstract

A closure scheme is developed for representing the mean vertical transport of a passive scalar within a convective boundary layer. The scheme predicts the evolution of the mean vertical profiles toward the form of the quasi-steady mean profiles observed in numerical large-eddy simulations of a convective boundary layer. The scheme models nonlocal transport and so is able to remedy several deficiencies of diffusive transport schemes.