Technical Support Document Ambient Air Quality Directive

Service contract study to lead the development of a technical support document on the use of modelling for various application domains under the revised Ambient Air Quality Directive.

In the revised European Ambient Air Quality Directive (AAQD), modelling is given a more prominent role as Europe recognises that the development of an effective air quality policy should also be supported by solid modelling results.  

To support practitioners within the EU Member States who are responsible for implementation of the AAQD, the European Commission – DG Environment commissioned a consortium, comprising of Ricardo, NILU and VITO to prepare technical guidance documents on the use of modelling and monitoring under the revised AAQD.   

Under the expert lead of Stijn Janssen, VITO was responsible for writing the Technical Support document on the use of modelling for various application domains under the Ambient Air Quality Directive, together with a group of 5 air quality modelling experts from across the EU.  The objective of the document is to serve as guidance for the implementation of air quality modelling under the AAQD.   

Expert guidance for efficient use of air quality models 

Guidance on the use of modelling systems is provided for each of the following application domains:  

• Assessment of the spatial representativeness of sampling points and overall design of a monitoring network, including the relocation of sampling points.

• Assessment of air pollutant concentration levels, including the estimation of exceedance situations, the contribution of natural sources, and the contribution from the resuspension of particulates following winter-sanding or winter-salting.

• Estimation of source apportionment to assess the contribution of the relevant sources of air pollution and quantify the potential impacts of their reduction as a starting point for the planning process. 

• Contribution to the design and selection of a set of measures and the overall quantification of the impact and effectiveness of an air quality plan to mitigate an exceedance situation in the shortest possible timeframe.

• Short-term air quality forecasts to warn the public about potential episodes and exceedances of the information and alert thresholds.

The document was extensively reviewed by FAIRMODE (the Forum for Air Quality Modelling), AQUILA, (the European Network of National Air Quality Reference Laboratories communities), and the Air Quality Expert Group. 

The final version of the guidance document can be found on the official European Union website: https://data.europa.eu/doi/10.2779/3343596