Influence of seasons, air mass origin and day of the week on size-segregated chemical composition of aerosol particles at a kerbside

Abstract

The size-segregated chemical composition of atmospheric aerosol particles (aerodynamic diameter Dp aer = 0.05–10 μm) was studied to reveal differences between seasons (winter/summer), air mass origins (East/West/North), and days of the week (weekday/Sunday). The goal was to identify the different particle emission sources for the first time at a kerbside in the city of Dresden, Germany. Ultra-fine particles (Dp aer = 0.05–0.14 μm, 12% of PM 10) consisted of approximately 80% OM (organic matter) and EC (elemental carbon), while fine particles (Dp aer = 0.14–1.2 μm) comprised about 55% ionic compounds with 44% OM and EC. The coarse fraction (Dp aer = 1.2–10 μm) consisted of approximately 65% ions/OM/EC and 20% metal oxides. Pb, Zn, and Cu showed crustal enrichment factors (CEF Si) > 100 for all particle sizes indicating strong anthropogenic influence. The Zn source was coal burning rather than traffic emissions. Doubled concentrations in winter were likely caused by coal combustion (Pb) and biomass burning (K), but also by a lower mixing layer height. Air masses from the East caused higher Pb and K concentrations. The origin of air masses had almost no influence on Cu, Cr, Fe, Mn, Zn and Ca, Si, Ti, indicating local sources such as traffic and heating. Possible actions against particle emissions are discussed.