Home – Home – Jornals – Atmospheric and Oceanic Optics 2023 number 6

Model estimates of the concentrations of black carbon (BC) in the surface air at four sites located on Kola Peninsula, in Arkhangelsk region, and on the territories of Nenetz and Gydansky nature reserves were carried out for winter and summer 2000-2016 based on satellite data. The long-range atmospheric BC transport is analyzed by the author's methodology for calculating the function of sensitivity to potential sources of submicron aerosol for the sites under study based on the statistics of back trajectories of air mass transport. The contribution of anthropogenic sources to BC concentration in every region generally prevails over the contribution of natural fires. The BC concentration in surface air is maximal over the Nenets Nature Reserve and, hence, over the Pechora Sea, where the main sources of this impurity all year round are gas flares at the Russian largest oil and gas provinces. The average, median, and maximal values of BC concentrations in the surface air in winter and summer are calculated from its interannual variations due to differences in air mass circulation, as well as from spatial and interannual variations in BC emissions from wildfires.

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 AOT component (-0.012 over 11 years) and the mass concentration of the absorbing substance (by 46.7 ng/m³ over 10 years).

The new coronavirus pneumonia has rapidly spread around the world. The World Health Organization emphasized that the SARS-CoV-2 coronavirus spreads mainly between people who are in close contact with each other, as well as in the case of touching contaminated surfaces followed by touching the eyes, nose, or mouth without first cleaning the hands. Possible permanent sources of the spread of the virus can be gathering of patients in hospitals in the case of non-compliance with the requirements for organizing the functioning of a hospital. Meteorological conditions can be a key factor influencing the spread of the virus in the case of an accidental release of virus-containing aerosol from such a hospital. Simulations are carried out with modern methods for solving a system of differential equations of the atmospheric boundary layer, which are adapted to describe the distribution of harmful atmospheric impurities over a real complex terrain considering urban buildings of various heights, forests, reservoirs, changing meteorological conditions, and many other factors.

The paper presents the results of studies of the content of particulate matter PM₁ - PM₁₀ in the atmosphere of the western coast of South Baikal with high temporal resolution. It has been established that PM are emitted into the atmosphere of Southern Baikal from both anthropogenic and natural sources. In winter, the influence of thermal power engineering increases, as evidenced by synchronous increases in the concentrations of submicron aerosol PM₁ and sulfur dioxide. In summer, remote forest fires make a significant contribution to atmospheric pollution with particulate matter. The relationship between the increase in the concentration of PM₁ in the atmosphere in the region under study and mesometeorological features (temperature inversions and mesoscale transfer of plumes from large thermal power plants) has been revealed. Increases in PM₁ concentrations in most cases occur during the night and morning hours, which is associated with a decrease in the thickness of the atmospheric boundary layer.

This paper represents an approach based on analysis techniques (statistical, microscopic, verification) of data provided by aerosol optical sensors, diffusion aerosol spectrometer, aspirating air sampler, and optical microscopy. The particulate matter size distribution and PM_2.5 mass concentration are studied. The low-cost measurement tools are verified with expensive precise equipment. The results show a high correlation (from 0.92 to 0.98) between different tools. The combination of considered devices can become a basis for a multipoint aerosol monitoring network for a wide urban territory with relatively low expenses.

A comparative assessment of the concentrations of PM_2.5 in the surface atmosphere over the territory of the city and over the water area of the Yenisei River was carried out. It is shown for time periods from several days to two years that, with rare exceptions, pollution over the river is lower than over the territory of the city. This pattern persists during periods of unfavorable meteorological conditions and during pollution of the urban atmosphere by the smoke of forest fires.

The results of experimental determination of near-surface aerosol density for particles of different composition and size have been published over many years. Based on the generalization of these data, as well as the results of our own field observations of microphysical characteristics and composition of Moscow aerosol, an algorithm and parameters for numerical estimation of mass concentration of submicron and micron urban aerosol are suggested. Using this algorithm, on the basis of experimental data on the size distribution function of aerosol particles in the diameter range 0.3-10 microns obtained during regular observations at IAP RAS in Moscow in 2020-2022, the mass concentration of near-surface aerosol of various fractions was calculated. A comparative analysis of the results of such an assessment and the data of synchronous measurements of mass concentration of aerosol particles using a portable aerosol spectrometer GRIMM 1.108 over the past two years has shown a good correspondence between the calculated and measured values. Density values for four ranges of aerosol particle sizes are selected for more correct numerical estimation of the mass concentration of urban aerosol of fractions PM_2.5 and PM₁₀.

Methods for estimating the buoyancy and rise characteristics of atmospheric pollutant emissions from high sources are discussed. They are based on the application of the relations of the theory of similarity and dimension for smoke plumes. Aerological sounding data and satellite images of plumes and their shadows on the earth's surface are used as additional information. The proposed approach to assessiment of the buoyancy flows of smoke plumes and the height of their rise was tested for three large thermal power plants in Siberia. A satisfactory agreement between the results and the normative characteristics of buoyancy flow for the chimneys under consideration has been established.

The paper considers changes in the state of the environment in Krasnoyarsk and its environs during the existence of the smoke of large-scale Yakut fires in August 2021. The appearance of smoke aerosols in the atmosphere led to a weakening of the passage of solar radiation to the Earth's surface and, accordingly, to a decrease in the temperature of the active soil layer and the surface air layer. Advection of cooled air with high relative humidity over the surface of the Yenisei River in the lower reaches of the Krasnoyarsk HPP formed cooling mists.

The outcome of the first tests of a measuring system designed for the monitoring of atmospheric aerosol content and meteorological parameters is considered. Based on the measurement results from August 2022, the data of the system prototypes, a calibrated optical aerosol sensor, and the on-site meteorological station are compared. The revealed drawbacks of the system design are described. The plans to improve and extend the system capabilities are discussed. A blueprint of a future multipoint aerosol monitoring network in Yekaterinburg and its neighborhood is presented.

The ecological state of the Arctic hydrocarbon deposit territories over the period 2013-2022 is estimated. Vegetation cover is considered an indicator of the ecological state of the territories under study. Based on the Terra/MODIS satellite data, the state of the vegetation cover of hydrocarbon fields in the Purovsky district of the Yamal-Nenets Autonomous Okrug is studied: Urengoyskoye, Vostochno-Tarkosalinskoye, Gubkinskoye, Vyngayakhinskoye, Komsomolskoye, and Tarasovskoye. Using the ArcGis geographic information system, the average values of EVI (Enhanced Vegetation Index) of the field vegetation cover for the full growing season from May 25 to September 20, 2013-2022, are calculated. The EVI minima and maxima for the territories are determined. Tendencies towards an increase in EVI in the final growing season over the 10-year period under study are found.

A time-varying flow velocity method for a conceptual model of river flow generation is implemented with the aim of improving flow routing in the Lena river basin. In contrast to constant velocity models, this approach uses a time-varying velocity which depends on the amount of flow generated in a land grid cell. The Manning equation is used to estimate flow velocity in the rectangular cross-sectional approximation for the river channel. Numerical experiments with constant and variable flow velocities made it possible to compare the model flow with the observed daily hydrographs at the runoff stations of Kyusyur, Tabaga, and Verkhoyanskiy Perevoz. The work provides an estimate of the heat flow from the Lena river basin to Kyusyur gauging station for 2002-2011.

An approach which combines remote and ground-based methods for monitoring oil-contaminated soil and vegetation cover is suggested. A map is presented that reflects the natural and anthropogenic structure of the territory of the Nefteyugansk region of the Khanty-Mansiysk Autonomous Okrug in the conditions of oil and gas production. The legend of the map shows 10 natural and 3 anthropogenic types of vegetation cover and the open surface of the Earth in the area located in the Salym-Ob flat terraced swamp-taiga landscape province. It was revealed that after oil spills, the soil and vegetation cover experiences a long-term negative impact. The NDVI values in the oil-contaminated areas are 0.1-0.3 lower than in the background ones. In satellite imagery in days close to those of ground-based surveys, the NDVI of oil-contaminated areas of sedge-sphagnum bogs is 0.45 (8.08.2020) and 0.42 (23.08.2021), respectively. In small-leaved and light-coniferous forests on sites with a negative impact of fresh oil spills, NDVI = 0.32 (25.09.2020) and 0.42 (23.08.2021), respectively. The concentration of oil products in contaminated soil samples lies in the range 280-580 g/kg, exceeding the approximately permissible concentrations by 70-145 times.