The results from studies of aerosol in the Arctic atmosphere are presented: the aerosol optical depth (AOD), the concentrations of aerosol and black carbon, as well as the chemical composition of the aerosol. The average aerosol characteristics, measured during nine expeditions (2007–2018) in the Eurasian sector of the Arctic Ocean, had been 0.068 for AOD (0.5 µm); 2.95 cm⁻³ for particle number concentrations; 32.1 ng/m³ for black carbon mass concentrations. Approximately two–fold decrease of the average characteristics in the eastern direction (from the Barents Sea to Chukchi Sea) is revealed in aerosol spatial distribution. The average aerosol characteristics over the Barents Sea decrease in the northern direction: black carbon concentrations by a factor of 1.5; particle concentrations by a factor of 3.7. These features of the spatial distribution are caused mainly by changes in the content of fine aerosol, namely: by outflows of smokes from forest fires and anthropogenic aerosol. We considered separately the measurements of aerosol characteristics during two expeditions in 2019: in the north of the Barents Sea (April) and along the Northern Sea Route (July–September). In the second expedition the average aerosol characteristics turned out to be larger than multiyear values: AOD reached 0.36, particle concentration up to 8.6 cm⁻³, and black carbon concentration up to 179 ng/m³. The increased aerosol content was affected by frequent outflows of smoke from forest fires. The main (99%) contribution to the elemental composition of aerosol in the study regions was due to Ca, K, Fe, Zn, Br, Ni, Cu, Mn, and Sr. The spatial distribution of the chemical composition of aerosols was analogous to that of microphysical characteristics. The lowest concentrations of organic and elemental carbon (OC, EC) and of most elements are observed in April in the north of the Barents Sea, and the maximal concentrations in Far East seas and in the south of the Barents Sea. The average contents of carbon in aerosol over seas of the Asian sector of the Arctic Ocean are OC = 629 ng/m³, EC = 47 ng/m³.

We discuss the measurements of black carbon concentrations in the composition of atmospheric aerosol over the seas of the North Atlantic and European sector of the Arctic Ocean (21 expeditions in 2007–2020). The black carbon concentrations were measured by an aethalometer and filter method. The comparison of the two variants of the measurements of the black carbon concentrations showed that the data acceptably agreed and can be used jointly. It is noted that the spatial distribution of black carbon over the ocean is formed under the influence of outflows of air masses from the direction of continents, where the main sources of emission of absorbing aerosol are concentrated. We analyzed the statistical characteristics of black carbon concentrations in five marine regions, differing by the outflows of continental aerosol. The largest black carbon content is a salient feature of the atmosphere of the North and Baltic Seas, surrounded by land: average values of concentrations are 210 ng/m³, and modal values are 75 ng/m³. In other regions (except in the south of the Barents Sea), the average black carbon concentrations are 37–44 ng/m³ (modal concentrations are 18–26 ng/m³). We discuss the specific features of the spatial (latitude-longitude) distributions of black carbon concentrations, relying on ship-based measurements and model calculations (MERRA-2 reanalysis data). A common regularity of the experimental and model spatial distributions of black carbon is that the concentrations decrease in the northern direction and with the growing distance from the continent: from several hundred ng/m³ in the southern part of the North Sea to values below 50 ng/m³ in polar regions of the ocean.

The results of the research are numerical estimates of the average fields of black carbon mass concentration in the surface layer of the atmosphere of the Arctic region obtained using the numeric technology referred to as fluid location of the atmosphere (FLA). The modelling has been based on measurements of the black carbon concentrations in the near-surface atmosphere obtained during the two cruises of the Professor Multanovskiy (28 July–7 September 2019) and Akademik Mstislav Keldysh (31 July–24 August 2020) research vessels. These measurements have been supplemented by measurements at stationary monitoring points located on the Spitsbergen and the Severnaya Zemlya archipelagoes. The simulation in the summertime demonstrates that areas of increased black carbon concentrations were observed over Northern Europe and, in 2019, also over the Laptev Sea basin. The obtained spatial distribution of mass concentrations of black carbon qualitatively agreed with the same data derived from the second Modern-Era Retrospective analysis for Research and Applications (MERRA-2) but showed quantitative differences. The average values of mass concentrations of black carbon in the modelling zones are as follows: 85.3 ng/m³ (2019) and 53.6 ng/m³ (2020) for fields reconstructed by the FLA technology; and 261.69 ng/m³ (2019) and 131.8 ng/m³ (2020) for the MERRA-2 data.

Seasonal and interannual variations in the atmospheric aerosol optical depth (AOD) are analyzed using multiyear (1995–2018) CE-318 (AERONET) and SP (Institute of Atmospheric Optics, Siberian...

The results of the analysis of seasonal and interannual variability of the aerosol optical depth of the atmosphere (AOD), the aerosol volume concentration, and the mass concentration of black carbon in the surface layer obtained at observations in Barentsburg (Spitzbergen archipelago) in 2011–2021 are presented. The annual behavior of all parameters is characterized by two maxima: spring (or winter-spring) and summer, apparently due to the transport of pollutants from the middle latitudes in the winter-spring period and smoke aerosol in summer. In the interannual variability, there are significant negative trends in the fine AOD component (−0.012 over 11 years) and the mass concentration of the absorbing substance (by 46.7 ng/m³ over 10 years).