Cool cities—clean cities? Secondary impacts of urban heat island mitigation strategies on urban air quality

Abstract

Cities are the predominant places for human beings to settle down, thus becoming more vulnerable to extreme weather events aggravating phenomena like heat stress and decreasing air quality aroused by inner city pollution. The excessive warming of impervious surfaces and additional release of anthropogenic heat promotes urban heat island (UHI) formation. Human activities lead to an increase of emissions of air pollutants which in turn influences the chemical composition of urban air. In this study, the mesoscale chemical transport model WRF-Chem is used for the urban area of Stuttgart to simulate the effect of UHI mitigation strategies such as urban greening and high albedo materials on the concentration of primary and secondary pollutants.