The Mathematics of Atmospheric Dispersion Modeling

The Gaussian plume model is a standard approach for studying the transport of airborne contaminants due to turbulent diffusion and advection by the wind. This paper reviews the assumptions underlying the model, its derivation from the advection-diffusion equation, and the key properties of the plume solution. The results are then applied to solving an inverse problem in which emission source rates are determined from a given set of ground-level contaminant measurements. This source identification problem can be formulated as an over-determined linear system of equations that is most easily solved using the method of least squares. Various generalizations of this problem are discussed and we illustrate our results with an application to the study of zinc emissions from a large smelting operation.