Seasonal changes in stable carbon isotope composition (Δ13C) in aerosol and gas phase at a suburban station in Prague

In this work, seasonal variations in the stable carbon isotope ratio (δ13C) of total carbon (TC, δ13CTC) and water-soluble organic carbon (WSOC, δ13CWSOC) in fine aerosol\nparticles (PM2.5) as well as in the total carbon of the gas phase (TCgas, δ13CTCgas) were studied. Despite the different seasonal compositions of carbonaceous aerosols, the\nisotope differences (Δδ13C) between the analyzed bulk aerosol parts and gas phases were similar during the seasons. This shows that the fractionation of stable carbon isotopes is a predominantly physical process in which the chemical composition of individual compounds in bulk aerosols does not play a major role