Variations in Measured Values of Lateral Diffusion Parameters

Abstract

The behavior of the quantity S = σ_y/xσ_θ for surface releases of tracers is examined. Variations in this quantity for different field programs are shown to be attributable largely to variations in sampling time t and averaging time t; larger values of S are found to be associated with longer τ and t. Other previously disregarded quantities, viz., mean wind speed and atmospheric stability, are shown to have potentially important effects. Two spectral models are presented which reproduce many of the observed features.