Abstract |
The necessity to study and investigate the levels of atmospheric pollutants is indisputable, mainly due of
their effects on human health. In this study, the concentration levels of carbonaceous aerosols namely total
carbon (TC), organic carbon (OC) and elemental carbon (EC) were investigated for the region of Attica with
the thermo-optical method TC-BC (Black Carbon) using the Total Carbon Analyzer TCA08 in combination
with the 7-λ Aethalometer AE33. Almost near real time measurements of total carbon took place at the
Thissio urban background station at the central premises of the National Observatory of Athens and the
sampling period lasted approximately one and a half years from November 2019 to May 2021. According to
the TC-BC method the equivalent fraction of organic carbon of carbonaceous aerosols (defined as OC = TC -
EC) was determined using the TC and EC values of the Total Carbon Analyzer and the Aethalometer
respectively, given as equivalent BC (eBC) instead of EC. However, the values obtained for BC and OC were
subjected to a correction process by comparison with values from filters for EC and the Aerosol Chemical
Speciation Monitor (ACSM) for organic matter OM, as black carbon particles are likely to be coated by other
compounds. The application of these corrections (BC to EC conversion with a factor of 0.75) resulted to the
extraction of the final time series, and allowed the study of the levels of carbonaceous aerosols on various
time scales (eg hourly, daily or seasonal). The final aim was to investigate the factors and sources
controlling the variation of OM and the results highlight the crucial role of biomass burning.
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