Abstract
It is well known that if turbulent mass convection is modelled as diffusion, errors result unless trajectories from the source (ath) to the point of observation (z p ) comprise many statistically-independent segments (Taylor, 1921). We show that this is not guaranteed merely by the Lagrangian timescale (τ) at the source being small (e.g., source at ground), but that a better criterion ist≫max[τ(h), τ(z p )], wheret is a typical travel time toz p .
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Mooney, C.J., Wilson, J.D. Disagreements between gradient-diffusion and Lagrangian stochastic dispersion models, even for sources near the ground. Boundary-Layer Meteorol 64, 291–296 (1993). https://doi.org/10.1007/BF00708967
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DOI: https://doi.org/10.1007/BF00708967