Study of the aerosol optical characteristics over the Romanian Black Sea Coast using AERONET data

Abstract

Present study is focused on the analysis of the similarities and differences in the aerosol properties retrieved from the sun-photometers operating at two sites in Western part of Black Sea, Romanian area, belonging to AERONET network (one on the sea shore at Eforie and the other on the Oil Platform Gloria at about 30 km offshore). Four years data sets (2014–2017) of aerosol optical depth, Ǻngström exponent, single scattering albedo and fine mode fraction, retrieved based on the AERONET algorithms, were used to identify the main aerosol types by season. The study emphasized similar monthly and seasonal variations for aerosol optical properties: mean multi-monthly values of AOD is from 0.1 to 0.3, AE varied between 1 and 2, and FMF varied from 0.7 to about 0.9. The dominant incidence of fine aerosol appears at both sites. Although some annual and seasonal differences between the coastal and marine stations were identified, both sites at the Black See Coast seem to be characterized by same aerosol, with a large fraction of anthropogenic component, composed by fine absorbing and non-absorbing aerosol. Pure marine fraction seems to be present mainly in autumn and in percentages varying from 5% to about 21% of the total mass, depending on the classification scheme. Regardless of the classification scheme used, the results show that dust aerosol is present at both stations less than 10%. Choosing an appropriate threshold range from various schemes to discriminate the aerosol types is not straightforward for sites on Black Sea Coast.