Some remarks on the validation of small-scale dispersion models with field and laboratory data

The objective of the paper is to contribute to the discussion on appropriate procedures for the evaluation of numerical models. This is done using as an example micro-scale atmospheric dispersion models as they are commonly applied for the prediction of local mean concentrations and higher percentile values. The paper starts with a description of problems associated with the direct comparison of numerical model results and measured data. After some remarks on numerical solutions to the problem, it concentrates on experimental strategies suitable for assuring the quality of validation data, and for quantifying systematic differences between simulated and experimental results.