Comprehensive chemical characterisation of size-segregated PM10 in Dresden and estimation of changes due to global warming

Abstract

To identify current and future human health risks from urban air pollution, size-segregated particle samples were collected under various seasonal and meteorological conditions in Dresden, Germany. Sampling days were grouped into twelve categories depending on season, air mass origin and temperature. A comprehensive chemical characterisation and mass closure were performed. The particulate matter (PM) mass concentration and composition were shown to be highly dependent on these categories. The highest PM mass concentrations were found on cold winter days, mainly due to compounds of anthropogenic origin. The current annual mean PM mass concentration and composition were calculated using the occurrence frequencies of the categories (weighted mean).Information about future changes of the occurrence frequencies of the categories was deduced from climate models. Assuming that PM concentration and composition within a given category do not change, the annual mean PM mass concentration and composition were calculated for two scenarios (weighted mean, 2071–2100). As a result, it was found that the annual mean PM mass concentration is likely to decrease slightly by 2100, mainly due to a decrease of sulphate and soot mass concentrations. Generally, chemicals originating from anthropogenic emissions (PAHs, trace metals) are estimated to decrease. However, it is concluded that emission reduction measures are still necessary to control urban air quality including PM even if climate change will lead to a certain reduction in PM.