4. Conclusions
The study of twenty years of policy making for air pollution control and management in Spain with the AERIS model for integrated assess- ment has allowed quantifying the effectiveness of the efforts directed towards the abatement of pollutants between 2000 and 2020. In gener- al, the witnessed reductions in the emissions of air pollutants have brought about benefits in the different aspects that are encompassed in the air pollution question. Regarding the compliance of Spain with the European air quality limit values for NO2 and PM10 specified by Di- rective 2008/50/EC, the number of zones in infringement exhibited a sustained decrease in the studied period. The decreases in the NO2 levels are due principally to measures that concentrate on road-traffic and general combustion processes (industrial and domestic), while the mit- igation of PM10 concentrations is also associated with power generation and off-road sources. Despite this, it has been anticipated that a number of air quality management zones will still be in infringement of such limit values under CLE scenarios in 2020 for both pollutants. The analy- sis of the contribution of the autonomous communities to such exceedances suggested that the air quality levels are not substantially influenced by transboundary dispersion from neighbouring communi- ties, being these contributions generally higher for NO2 than for PM2.5.