Black Carbon in urban emissions on the Polar Circle

This work studied emissions of aerosol Black Carbon (BC) from an urban area in the Arctic region. This pollutant species has significant climate forcing potential at high latitudes. Three months of real time BC measurements were made at an isolated location 4 km south-east of Salekhard City, on the Polar Circle in North-Western Siberia. Based on conditional probability function (CPF) analyses, wind directions from the city were correlated with high BC concentrations, tens of times higher than the arctic background observed nearby. According to official statistical data, diesel fuel and natural gas combustion are the primary sources of emissions in Salekhard. The diurnal BC trend identifies the significant impact of transport and heating emissions. In April-May, maximum BC concentrations of ~ 430 ng/m³ were recorded in the urban emission. In July, during area-wide wildfires, concentrations reached ~ 960 ng/m³; at this time the short-wavelength (470 nm absorption) data exceeded the long-wavelength (880 nm absorption) by a record value of ~ 260 ng/m³. This result identifies the smoke plume contribution to the atmosphere loading and deterioration of air quality in the urban environment.