Numerical modeling of interaction of nonstationary divergent flow with a convective atmospheric boundary layer over the ocean

By using the numerical model suggested in a previous work (Khain and Ingel [1988]) the structure and dynamics of the atmospheric boundary layer in the trade wind zone is investigated under conditions when the interaction of a large-scale wind with convection is important. It is shown that a two and-one half dimensional numerical model reproduces many essential features of the boundary layer considered; accounting for cold air advection, it allows computations of convective processes for long periods (40 hours or more). This provides a description of such phenomena as convective outbreaks with periods of about 10 hours. The period of convective intensity oscillations that was obtained in computations correlates well with observational data. Account for the convection leads to a considerable growth in the atmospheric boundary layer thickness and in latent heat fluxes from the ocean.