Non-Local Vertical Transport in the Shear-Free Convective Surface Layer: New Theory and Improved Parameterization of Turbulent Fluxes

During the last several decades the surface frictional processes in the shear-free convective boundary layer (CBL) are considered conceptually in the spirit of the Prandtl (1932) theory of free convection, implying the ideas of (i) universal chaotic turbulence and (ii) local correspondence between turbulent fluxes and mean gradients. Accordingly the fluxes of heat and water vapour in the atmospheric surface layer are parameterized disregarding gross features of the CBL. Conventional practical tools are either the Monin-Obukhov similarity theory or simple downgradient turbulence closure models.