## 1 Introduction
Accurate determination of the amount of soot particles is important for climate monitoring and forecasting based on atmospheric data assimilation [12]. In Europe and in the USA, studies of the distribution of suspended particles in the atmosphere have been carried out since the end of the twentieth century, and active development of such studies is currently taking place in Asian countries [13; 14]. In China, for example, the weather forecast is always accompanied by information on the value of the PM\({}_{2.5}\) index. This information is extremely necessary since air pollution in many megapolises of China has reached critical values. Taking into account the pandemic situation in 2020, one can expect that a reduction in automobile and air traffic should lead to decreasing air pollution. Indeed, [PERSON] et al. [15] made a quantitative comparison of aircraft engine emissions caused by domestic and international commercial flights before and after the COVID-19 pandemic in Turkey. They have shown a significant decrease in the amount of air pollutants. For example, the updated global exposure estimates of PM\({}_{2.5}\) in different regions of the world [16] demonstrate further advances in characterizing global population exposure to ambient air pollution. The global coverage in this research allows for estimating concentrations of air pollutants in areas without extensive ground monitoring, including, for example, rural areas with large emissions from households using coal as fuel. Using these estimates in combination with model simulations of chemical transport can provide information on sector-specific contributions to air quality management. However, to obtain more correct information, monitoring of ambient air pollution must be in place and comprehensive. Management of air quality is a very effective tool for assessment of air pollution on different scales--national (macro), city (medium), and local [17]. The successful implementation of the management of air quality plans in different regions depends on the efficiency of its key components, e.g., aim, monitoring network, emission inventory, air quality modeling, etc. In the Russian Federation, approximately half of its population lives in cities, where air pollution levels are above MPC [18]. However, automated monitoring of PM\({}_{10}\) and PM\({}_{2.5}\) is currently organized only in large cities, such as Moscow, St. Petersburg, Sochi, Kazan, and others [19]. Compared to other countries, the surveillance network is not sufficiently developed and informative ([[http://aqicn.org/city/beijing/--The](http://aqicn.org/city/beijing/--The)]([http://aqicn.org/city/beijing/--The](http://aqicn.org/city/beijing/--The)) World Air Quality Index, accessed on 14 June 2022). Even less data is available on the composition of PM\({}_{10}\) and PM\({}_{2.5}\), although these particles are excellent adsorbents of various pollutants, such as trace elements and radioactive isotopes, complex organic substances, etc. [20]. This is especially true for microparticles PM\({}_{10}\) and PM\({}_{2.5}\), which is soot of natural (fires) and anthropogenic (products of fuel combustion and tire wear) origin. In the Black Sea region, studies on the chemical composition and quantity of aerosols in the atmosphere have been rarely carried out, as compared to, for example, the Mediterranean Sea region [21; 22]. As a rare example, researchers [22] have carried out studies of aerosols in the Blue Bay area of the Black Sea on the transect from Gelendzhik to the open sea, as well as at several coastal stations. It has been discovered that terrigenous sources are located at a short distance, and variations in the wind can completely change the elemental composition of aerosol samples during the synoptic period. The chemical composition of aerosols in the eastern Black Sea was studied at a station located in the mountains of Turkey, 50 km from the Black Sea coast in 2011-2013 [23]. The authors concluded that there were no seasonal variations in the concentration of anthropogenic elements in aerosols.