There is a strong interest from several civil and military agencies in the U.S. and in Europe in an improvement to existing model evaluation methodologies. This interest focuses mainly on model acceptance criteria, summaries of users needs, and preparation of data bases and software for use in model evaluation.

Our presentation will discuss recent results obtained from a two-part study where we 1) test and develop comprehensive evaluation methodologies for urban dispersion models, and 2) we investigate requirements of users needs for atmospheric transport tools. A set of comprehensive urban model evaluation methodologies is being developed, including a) scientific evaluation criteria, b) statistical evaluation methods and criteria, c) development of methods for communicating results and uncertainties to decision-makers, d) field and laboratory data base development, and e) application of evaluation methods to a few field data bases as a demonstration exercise. The study emphasizes general categories of models and scenarios rather than specific cases.

The second part of the research assesses the needs and capabilities of users of atmospheric transport and dispersion models for chemical or biological (CB) agent releases during a hazardous event or a terrorist attack. The work for this project is divided into several phases that involve the establishment of the character of the atmospheric transport and dispersion models and the modes in which they are used. During the course of this project a questionnaire was developed and sent to atmospheric dispersion modelers to obtain data for the final user needs assessment. Data obtained through the questionnaire has been analyzed for the ranking of features that might be considered for future transport models. The final phase of the project will provide some estimates of the feasibility and cost of including higher-ranking features in future atmospheric transport models.