5.8
The Use of Concentration Fluctuation Variance Predictions in Model Evaluation
R. Ian Sykes, Titan Research and Technology, Princeton, NJ
Uncertainty in the transporting wind field is a major contributor to the uncertainty in an atmospheric dispersion prediction; the wind uncertainties include both turbulent velocity fluctuations and measurement/observational limitations. This makes comparison between dispersion model predictions and observed concentration values a difficult task, since we may not know how accurately a prediction can be made using a particular set of input data. Turbulence closure techniques provide a means of relating the wind field uncertainties to the dispersion prediction uncertainties, and therefore provide a basis for objectively characterizing a significant component of the overall model performance. The closure methodology and the requirements for use in model evaluation studies will be discussed.
Session 5, concentration fluctuations, model uncertainty and evaluation
Wednesday, 22 May 2002, 9:00 AM-1:30 PM
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