Future trends in ambient air pollution and climate in Germany - Implications for the indoor environment

Until now, only a few studies have addressed the effects of climatic changes on the microclimate in indoor areas. Although global warming presents a problem worldwide, the extent of climate change varies greatly according to region. In this work, climatic changes and their influences on indoor areas in Germany are discussed. Air temperatures, quantity of summer days, sunshine hours and precipitation were extracted from the databases of the German National Meteorological Service. In addition, data on ozone, nitrogen dioxide, PM10 and PM2.5 were collected from eight monitoring stations in different urban locations. With the aid of single-box models, the effects of these parameters on indoor air were assessed. Furthermore, temperature and humidity measurements were performed in a thermally insulated house during a 14-day period of fine weather. Finally, trends for the indoor temperature through to the year 2040 were estimated. With the current thermal insulation standards, effects of climate change are associated with an increase in indoor temperatures, which can easily lead to overheating in the event of heatwaves. Nitrogen oxides and ozone are subject to strong daily and seasonal fluctuations. Particle concentrations are declining in Germany. The entry of outdoor air contaminants into the indoor area is essentially dependent on the air exchange. On the whole, measurements and simulations show that climate change substantially influences the indoor air quality. This will have consequences in the medium term as regards measures for thermal insulation and for regulation of the air exchange in private and public buildings.