The Theory of Turbulent Diffusion in the Atmosphere (I)

Abstract

The essential features of the turbulent diffusion in the atmosphere exist in that the atmospheric turbulence consists of eddies, whose dimensions are very different from each other, and that the scale of eddies effective for the diffusion is related to the scale of the diffusion phenomenon. In the present paper, the author treated theoretically the turbulent diffusion from a point source by means of the relations between the statistical quantities of the turbulence and the spatial length under analysis. Using this method, it was made possible to take into consideration the circumstances that small eddies are effective for the diffusion near the point source and large eddies become effective, as the particles depart from the source.
By this investigation, the so-called Lagrangian correlation coefficient was derived and the interrelation between the Eulerian and Lagrangian correlation coefficients was obtained.