The structure and form of this document is intended to facilitate model users and researchers in determining the requirements, possibilities and limitations when using models for assessment purposes. It is presented as a series of chapters where Chapters 2 – 4 deal with an interpretation and understanding of the air quality directive, in regard to modelling, and Chapters 5 – 8 describe modelling applications and methodologies.
This guidance document is complementary to the previously developed “Guidance on the use of models for the European Air Quality Directive” in that it concentrates on the actual modelling methods, rather than on the interpretation and general use of models for AQ Directive applications. It provides guidance on the use of models for air quality assessment and planning, with particular regard to modelling NO2 concentrations. The document is intended as guidance for authorities and modellers to help stimulate ‘good practise’ in air quality modelling and provide an overview and description of methods and tools available for air quality modelling. Since NO2 is generally a local and urban scale problem, this document concentrates on applications within cities.