High concentrations of air pollutants, especially particulate Matter (PM10) and ground-level ozone, are known for their negative impacts on human health and in the case of ozone even on vegetation. As a member of the European Union, the Federal Republic of Germany is responsible for ensuring the compliance of immission limits according to the Directive on Ambient Air Quality and Clean Air for Europe (2008/50/EG) and the 39th Ordinance for Implementing the Federal Immission Control Act. To intervene at an early stage with emission-reducing measures an estimation of future air quality is required. Changes of meteorological parameters associated with climate change and political decisions that affect the emissions of conventional pollutants have a considerable impact on future air quality. Thus, both factors directly affect the compliance of applicable immission limit values in future. The importance of these factors on the development of air pollution, as well as their coupled impacts, can only be investigated with an analysis of appropriate climate change and emission scenarios. The aim of this research and development project KLENOS is to quantify the impacts of climate change and energy policy change on air quality with a scenario approach. It involves the implementation of regional climate and subsequent chemical transport simulations. A further objective is the identification of typical weather types, which are related to the exceedance of limit values for PM10 and ozone. Based on long climate simulations future frequency of these typical weather types and therefore future tendencies of the exceedance of limit values for PM10 and ozone can be estimated.<BR>Quelle: Forschungsbericht