Experiments with a Markov chain dispersion model applied to vertical dispersion in the surface layer

The basis of the model and parameterizations of mean and turbulent wind components are presented. Model results for a near surface source in neutral stratification show good agreement with Porton data. Elevated source simulations indicate that the mass mean pollutant height (zeta hyperon) variation is normalized using a nondimensionalized downwind coordinate incorporating advective wind speed and wind shear, while the distribution equivalent Gaussian spread (Sigma sub zeta) shows a fair degree of independence of source height. Simulations for nonneutral cases show trends with stability variation in agreement with observation but suffer from lack of an adequate empirical observational base.