Parameterization of Overwater Diffusion: Separation of Relative Diffusion and Meander

摘要

Data compiled from surface releases of SF6 gas in a purely over water environment are used to parameterize both relative and single particle diffusion in the lateral direction. Relative diffusion is found to be adequately described by surface layer stability for ranges to 10 km. Single particle diffusion, often referred to as meander, is not found to be strongly related to surface layer stability, but does correlate well with measured lateral wind direction variance. A near field approximation closely predicts the single-particle lateral diffusion for these data, suggesting that meander is dominated by very scale turbulence, even when considering travel times of 30-60 minutes.