Variability of black carbon aerosol concentrations and sources at a Mediterranean coastal region

To investigate the temporal variation of aerosol optical properties and evaluate the main emission sources of black carbon (BC) considering different seasons in a typical Mediterranean coastal environment, a field campaign was conducted during February-July 2019 at the Central Adriatic coastal area. Real-time measurements of aerosol light absorption were continuously obtained using an aethalometer while the Aethalometer model source apportionment data, optimized by using levoglucosan measurements, were evaluated against the modelling results of the LOTOS-EUROS chemical transport model. The measured mean equivalent BC mass concentration of 0.57 +/- 0.64 mu g m(-3) was the lowest observed in the Mediterranean region. BC from fossil fuel (BCff) dominated the area throughout the study period with a maximum in winter and elevated levels by the approaching summer tourist season. Diel variability of BC concentrations from biomass burning (BCbb) was observed during stable winter conditions, with clear morning and evening concentration peaks, consistent with the profile of residential heating by wood burning. Up to 88% of BC concentrations were attributed to European emission sectors, with stationary source combustion, transportation, shipping and agriculture sectors being the most influential contributors. Source apportionment of BC highlighted that, in addition to biomass burning, small combustion fossil fuel sources, including land traffic and shipping, should be more strictly controlled in order to limit BC pollution in Mediterranean coastal areas. This study serves as a basis of comparison for future studies addressing air quality and pollution source apportionment in the Adriatic and/or the Mediterranean coastal regions in efforts of mitigation and adaptation to climate change.