A New Formulation of the Probability Density Function in Random Walk Models for Atmospheric Dispersion
Simulation of at mospheric diffusion in vertically inhomogeneous skewed turbulence, which is typical for the daytime boundary layer, is investigated. Particle trajectories are simulated by using the Langevm equation. The main objective is to introduce a formulation of the probability density function (PDF) of the vertical velocity fluctuation based on a fourth order expansion after Hermite polynomials (Gram-Charlier expansion). The statistics of the turbulence are introduced by forcing the moments of the Gram-Charlier expansion to equal the parametrized moments of atmospheric turbulence.
KeywordsProbability Density Function Probability Density Function Hermite Polynomial Atmospheric Dispersion Stochastic Lagrangian Model
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- Tassone, C., Gryning, S.-E., Rotach, M.W., 1994, A random walk model for atmospheric dispersion in the daytime boundary layer. In Air Pollution Modelling and its Application X, Edited by Gryning, S.-E. and Millan, M.M., Plenum. New York and London, pp.204–250Google Scholar
- Tassone, C., 1995, A Lagrangian model for dispersion in the daytime boundary layer, Ph.D.-thesis, Risø National LaboratoryGoogle Scholar