Modelling anthropogenic aerosol sources and secondary organic aerosol formation: a wintertime study in central Europe

Abstract. Anthropogenic aerosol particles remain a significant air quality concern in central Europe, particularly during winter months. This study employs the chemistry transport model COSMO–MUSCAT (COnsortium for Small scale MOdelling coupled with the MUltiScale Chemistry Aerosol Transport) to investigate particulate matter sources, with a focus on emissions from residential heating. The model results are compared with winter measurements from one site in Germany and two sites in the Czech Republic, where solid fuels are commonly used for heating. A non-reactive tagging method tracking primary organic matter (OM) reveals a high contribution from residential heating. Although the magnitude and temporal changes of the model results mostly agree with total OM values at two measuring stations, it appears to underestimate measurements at a site in the central Czech Republic. This underestimation is partly attributed to the inadequate representation of secondary organic aerosol (SOA) emitted from wood combustion. The study highlights the impact of anthropogenic volatile organic compounds (AVOCs) on SOA formation, which are currently underrepresented in air quality models. Sensitivity tests adjusting SOA yields and AVOC emissions increase OM concentrations by up to 40 % at the measurement sites. These findings emphasise the need for accurate parameterisation of AVOC-derived SOA formation and residential heating emissions to better tackle wintertime air quality challenges in central Europe.