LAUSR

The article presents the results of a study of black carbon concentrations in the atmospheric boundary layer over the Baltic and North seas, the North Atlantic, and Norwegian, Barents, Kara, and Laptev seas from June 30 to September 29, 2017, on cruises 68 and 69 of the R/V Akademik Mstislav Keldysh. Black carbon has a significant impact on climate change and pollution in the Arctic. It forms as a result of incomplete combustion of fossil fuels (primarily coal and oil) and biomass or biofuels. It consists of submicron particles and their aggregates and can be transported long distances from their source. Samples were taken by pumping air for 4–6 h through Hahnemule quartz filters at a height of 10 m above sea level in a headwind to prevent exhaust from the smokestack from entering the filters. The black carbon content was subsequently determined in a laboratory with an aethalometer. The backward trajectories of air mass transfer and the transported black carbon particles to the sampling points were calculated by the HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model on the NOAA website at http://www.arl.noaa.gov/ready.html. Studies show low black carbon concentrations (<50 ng/m3) along the expedition’s route when the air masses came from background regions of the North Atlantic and Arctic. High black carbon concentrations (100–200 ng/m3 or more) are characteristic of active shipping areas (southwestern Baltic, North Sea) and near ports (e.g., Reykjavik), as well as the arrival of air masses from industrialized areas of Europe in the southeastern Baltic and from oil and gas field areas where gas flaring is carried out (North, Norwegian, and Kara seas).