Micro-scale air quality modelling refers to air quality modelling at high spatial resolution (typically down to a scale in the order of one meter), usually focused on urban environments. Based on discussions within the FAIRMODE community, it is noted that this type of modelling applications is more and more used in an AQD policy context. This evolution is driven by the fact that more and more exceedances occur at local hotspots which require high spatial resolution for understanding their causes and setting up specific and localized measures to mitigate the problem. The focus points of this crosscutting task are:

• 1 Identifying current uses of microscale AQ modelling, including challenges in their implementation and collecting best practices in relation to the assessment and management under the AAQD.
• 2 Determining how to derive an annual averaged concentrations (and other AQD statistics such as percentiles) with a micro-scale model as a first step to discuss how to use microscale models for air quality assessment or planning in the framework of AQ directives.