A general review is given of the characteristic problems encountered in the parameterization of the atmospheric boundary layer in large-scale models. Only those parameterizations that interact with the large-scale flow are considered. Two aspects are especially important and require further study: the interaction of the boundary layer with clouds and the use of integrated parameterizations instead of a multilevel treatment. It is also necessary to carry out further experiments in order to evaluate the effect of a particular parameterization on the results of large-scale simulations or forecasts.
1Also: Free University, Amsterdam, the Netherlands.