Abstract
Keywords - Emission, Air Quality, Road Transport, Trend, Other Sources
Abstract - The emission development of stationary and mobile sources including two wheelers, passenger cars, light and heavy-duty vehicles and busses are considered. For kerb-side sites the contribution and development of mobile sources are main contributors. The contribution and development of stationary sources are important for the impact on air quality in cities mainly for urban background levels. UBA and the European Environmental Agency have a reliable database for all sources up to 1998 resp.1990. Emission data for most sources are available from local and state government institutions. For road transport the German UBA has developed an emission model TREMOD and the European Commission a model called FOREMOVE based on COPERT which allow the forecast in the future until 2020.
Emissions before 1980 were lower than the emissions from 1980 on. With the increase of vehicles since 1950 also emissions of road transport increased, especially for NOx in the time from 1970 to 1980 where the reduction measures for CO and NMHC (Non methane hydro-carbons) from passenger cars increased the NOx emissions. Later on the introduction and permanent improvement of the catalytic converter technology led to declining emissions from passenger cars. Emissions from duty vehicles are nowadays also improving. The contribution of road transport is declining and therefore in the future air quality regarding CO-, NMHC-, NO2- and PM-concentrations are improving as well.
At sites where most inhabitants are exposed the EU air quality standards derived by WHO coming into force in 2010 will be met. Future emissions from road transport tend to be low enough to ensure a good air quality in German and other European cities.
Long-range transport of emissions over the atlantic and also from eastern neighbour countries have to be considered in the future more detailed. Regarding the precursors HC and NOx the transport of air masses over wider distances (from Asia and USA) is important as well.