EUCAARI was a EU 6th Framework Programme Integrated Project on aerosol, cloud, climate and air quality interactions
The role of aerosols in European air quality was one of the major foci of EUCAARI. The carbonaceous aerosol emissions of EUCAARI together with the new organic aerosol module used in PMCAMx based on the volatility basis set approach resulted in significant improvement of the agreement between measurements and predictions of regional organic aerosol concentrations. There is evidence that the residential wood-burning emissions in at least some regions (e.g., Sweden, East Germany, Switzerland) are significantly underestimated. Also the wintertime emissions of ammonia are probably overestimated by a factor of 3 or so.
The reduction in ammonia emissions is one of the most effective ways to reduce aerosol mass concentrations in Europe. Reduction in NOx is also effective, but might lead to higher ozone levels. Reduction in SO2 emissions will reduce particulate air pollution especially in the Eastern Mediterranean area. Reduction of organic aerosol concentrations is a lot more challenging and will require reductions of gas and aerosol emissions from transportation and biomass burning.