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Based on the multiyear measurements in the surface atmospheric layer (from five stations) and regular flights of aircraft laboratory over the background region of Southwestern Siberia, the compositions of mass concentrations of submicron aerosol and absorbing substances (soot and black carbon) are analyzed. The annual average concentrations of submicron aerosol and black carbon were found to be maximal in 1997, 2012, and 2016, when the largest numbers of wildfires occurred across the entire territory of Siberia. No significant, unidirectional trend of interannual variations in the concentration of submicron particles was observed, while the concentration of absorbing substance reliably decreased by 1.5% each year. To estimate the effect of urban pollutants, mass concentrations of aerosol and absorbing substance in the surface layer at the Aerosol Station (in the suburban region of Tomsk) were compared to those at the Fonovaya Observatory (in the background region). It was shown that the largest contribution of anthropogenic sources in the suburban region was observed in the winter season, while minimal difference was observed in the warm period of the year. The seasonal behavior of the concentrations of elemental carbon at three stations in Novosibirsk Oblast almost completely matched the dynamics of the variations in the black carbon concentration in the atmosphere of Tomsk Oblast. Data of aircraft sensing in the troposphere of the background region of Southwestern Siberia (2000–2018) were used to determine the average values of the vertical distribution of the submicron aerosol and black carbon concentrations in the altitude range of 0.5–7 km for each season. It was found that at altitudes of 0.5–7 km, there were no unidirectional trends in submicron aerosol; however, there was an increase of black carbon concentration at all altitudes with a positive trend of 5.3 ± 2.2% per year at an altitude of 1.5 km, significant at a p-value = 0.05. [ABSTRACT FROM AUTHOR]

The abnormally high temperature and the deficit of precipitation in Siberia in summer 2016 contributed to the development of massive forest fires, which resulted in pyrogenic emission in the atmosphere of various biomass burning products. This paper presents the analysis results of the spatial and temporal variations of black carbon (BC) in the atmosphere over Northern Eurasia during the 2016 Siberian wildfires using the MERRA-2 reanalysis data. The spatiotemporal evolution of BC anomalies is presented, with estimates of the increase in BC mass during wildfire period. The peculiarities of large-scale atmospheric circulation responsible for BC transport from Siberia to Central Europe are discussed. The estimates of spatial scale, effective height and speed of the long-range anomalous (from east to west) transfer of air masses in the atmosphere over Northern Eurasia in July 2016 are obtained. Changes in the optical and microphysical characteristics of biomass-burning aerosol during its long-range transport are also discussed. A comparison of daily variations in surface BC concentrations at the polar observatory Tiksi with those in BC column mass density from MERRA-2 revealed a high correlation between local and integral characteristics of BC during arriving air masses from Siberian wildfires. • Black‑carbon air pollution over Eurasia in July 2016 was caused by Siberian wildfires. • Atmospheric dipole-type blocking promoted long-range westward black carbon transfer. • Westward shift of atmospheric block led to transfer of black carbon deep in Europe. [ABSTRACT FROM AUTHOR]

In low human activity area such as Arctic and ocean, even a small inflow of aerosols originated in anthropogenic and forest fire emissions can be an influence on radiation, cloud, and precipitation via direct and indirect effects of aerosol. Hence it is important to understand the aerosol transport to the low human activity area. The large and continuous forest fire emission occurred around Lake Baikal of Siberia in September 2016. The maximum surface concentration of black carbon (BC) was observed by Arctic cruise of R/V Mirai (MR16-06) in 25–26 September around Aleutian Islands. We successfully reproduce the maximum of carbon concentration in 25–26 September around Aleutian Islands with the aerosol transport simulation of the Nonhydrostatic Icosahedral Atmospheric Model (NICAM) – SPRINTARS with horizontal resolution of 56 km. These results imply the long-range transport of BC from Lake Baikal to Aleutian Islands, however, the aerosol transport simulation possibly involves in uncertainties related to the injection levels of emission, emission dataset, and horizontal resolution of the model. Thus, the sensitivity of emission should be addressed to validate the uncertainty ranges of the aerosol transport impact on the low human activity area. To estimate the BC emission impact, we performed the sensitivity simulations of the NICAM-SPRINTARS using the multiple schemes of emission, the multiple emission dataset (GFAS, GFED, and FINN), and the multiple horizontal resolutions (220 km and 56 km). One noticeable impact of emission scheme change was achieved by replacing the model's injection height of forest fire events by the observational injection height, and the BC concentration in remote area is relatively large with the emission scheme of constant injection height (about 3 km). The horizontal resolution with 56 km is capable of simulating fine scales transport processes of BC. [ABSTRACT FROM AUTHOR]