Supporting the improvement of air quality management practices: The "FAIRMODE pilot" activity.

This paper presents the first outcomes of the "FAIRMODE pilot" activity, aiming at improving the way in which air quality models are used in the frame of the European "Air Quality Directive". Member States may use modelling, combined with measurements, to "assess" current levels of air quality and estimate future air quality under different scenarios. In case of current and potential exceedances of the Directive limit values, it is also requested that they "plan" and implement emission reductions measures to avoid future exceedances. In both "assessment" and "planning", air quality models can and should be used; but to do so, the used modelling chain has to be fit-for-purpose and properly checked and verified. FAIRMODE has developed in the recent years a suite of methodologies and tools to check if emission inventories, model performance, source apportionment techniques and planning activities are fit-for-purpose. Within the "FAIRMODE pilot", these tools are used and tested by regional/local authorities, with the two-fold objective of improving management practices at regional/local scale, and providing valuable feedback to the FAIRMODE community. Results and lessons learnt from this activity are presented in this paper, as a showcase that can potentially benefit other authorities in charge of air quality assessment and planning.

Influence of residential wood combustion on local air quality.

The importance of wood combustion to local air quality was estimated by measuring different air pollutants and conducting chemical mass balance modelling. PM10, PM2.5, PAHs and VOC concentrations in ambient air were measured in a typical Finnish residential area. Measurements were conducted in January-March 2006. For some compounds, wood combustion was clearly the main local source at this site. The effect of wood combustion was more clearly seen for organic compounds than for fine particle mass. For fine particles, background concentrations dominated. However, very high, short-lived concentration peaks were detected, when the wind direction and other weather conditions were favourable. For organic compounds, the effect of wood combustion was seen in diurnal and in two-week average concentrations. PAH-concentrations were often several times higher at the residential area than in the background. Benzene concentrations showed similar diurnal pattern as the use of wood and benzene/toluene ratios indicated that wood combustion is the most important source. A chemical mass balance model was used for studying the effect of wood combustion on the measured concentrations of VOCs. Model results showed that the main local sources for VOCs at Kurkimäki are wood combustion and traffic. Wood combustion was clearly the most important source for many compounds (e.g., benzene).