Employing turbulent and meandering time scales to modeling the contaminants enhanced horizontal dispersion

A Lagrangian stochastic particle dispersion model composed of two coupled Langevin equations, employing a new transport parameterization is used to study the meandering enhanced dispersion in a low wind speed stable atmospheric boundary layer (ABL). The meandering parameterization introduced into the Lagrangian stochastic dispersion model is expressed in terms of a characteristic phenomenological meandering period and of the horizontal local turbulent time scales associated with a fully developed turbulence. The results of this new method are shown to agree with the field observations of Idaho experiments and also with other different meandering dispersion models. The major advance shown throughout this paper is as it follows: For air quality modeling it is highly necessary to include a parameterization that allows a correct description of the dispersion caused by the low-frequency horizontal wind oscillations. (C) 2009 Elsevier B.V. All rights reserved.