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Development of reliable source emission inventories is particularly needed to advance the understanding of the origin of Arctic haze using chemical transport modeling. This study develops a regional anthropogenic black carbon (BC) emission inventory for the Russian Federation, the largest country by land area in the Arctic Council. Activity data from combination of local Russia information and international resources, emission factors based on either Russian documents or adjusted values for local conditions, and other emission source data are used to approximate the BC emissions. Emissions are gridded at a resolution of 0.1° × 0.1° and developed into a monthly temporal profile. Total anthropogenic BC emission of Russia in 2010 is estimated to be around 224 Gg. Gas flaring, a commonly ignored black carbon source, contributes a significant fraction of 36.2% to Russia's total anthropogenic BC emissions. Other sectors, i.e., residential, transportation, industry, and power plants, contribute 25.0%, 20.3%, 13.1%, and 5.4%, respectively. Three major BC hot spot regions are identified: the European part of Russia, the southern central part of Russia where human population densities are relatively high, and the Urals Federal District where Russia's major oil and gas fields are located but with sparse human population. BC simulations are conducted using the hemispheric version of Community Multi‐scale Air Quality Model with emission inputs from a global emission database EDGAR (Emissions Database for Global Atmospheric Research)‐HTAPv2 (Hemispheric Transport of Air Pollution) and EDGAR‐HTAPv2 with its Russian part replaced by the newly developed Russian BC emissions, respectively. The simulation using the new Russian BC emission inventory could improve 30–65% of absorption aerosol optical depth measured at the AERONET sites in Russia throughout the whole year as compared to that using the default HTAPv2 emissions. At the four ground monitoring sites (Zeppelin, Barrow, Alert, and Tiksi) in the Arctic Circle, surface BC simulations are improved the most during the Arctic haze periods (October–March). The poor performance of Arctic BC simulations in previous studies may be partly ascribed to the Russian BC emissions built on out‐of‐date and/or missing information, which could result in biases to both emission rates and the spatial distribution of emissions. This study highlights that the impact of Russian emissions on the Arctic haze has likely been underestimated, and its role in the Arctic climate system needs to be reassessed. The Russian black carbon emission source data generated in this study can be obtained via http://abci.ornl.gov/download.shtml or http://acs.engr.utk.edu/Data.php.

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[1] An intensive spring aerosol sampling campaign over northwestern and northern China and a megacity in eastern China was conducted in the spring of 2007 to investigate the mixing of Asian dust with pollution aerosol during its long-range transport. On the basis of the results of the three sites near dust source regions (Tazhong, Yulin, and Duolun) and a metropolitan city (Shanghai), three dust sources, i.e., the western high-Ca dust in the Taklimakan Desert, the northwestern high-Ca dust and the northeastern low-Ca dust in Mongolia Gobi, were identified on the basis of the air mass trajectories and the elemental tracer analysis (e.g., Ca/Al, SO 4 2− /S, Ca 2+ /Ca, and Na + /Na). The western dust was least polluted in comparison to the other two dust sources. The results evidently indicated that the dust could have already mixed with pollution aerosol even in near dust source regions. The concentrations of As, Cd, Cu, Pb, Zn, and S were elevated several times at all sites during dust days, showing the entrainment of pollution elements by dust. The secondary SO 4 2− was observed to show much higher concentration due to the heterogeneous reaction on the alkaline dust during dust storm, while the concentrations of NO 3 − and NH 4 + decreased owing to the dilution of the local pollution by the invaded dust. The western dust contained relatively low anthropogenic aerosols, and it mainly derived from the Taklimakan Desert, a paleomarine source. The northwestern dust had a considerable chemical reactivity and mixing with sulfur precursors emitted from the coal mines on the pathway of the long-range transport of dust. The northeastern dust reached Shanghai with high acidity, and it became the mixed aerosol with the interaction among dust, local pollutants, and sea salts. Comparison of the speciation of the water-soluble ions on both nondust and dust days at all sites illustrated the evolution of major ion species from different dust sources during the long-range transport of dust. The mixing mechanisms of the dust with the pollution aerosol on the local, medium-range, and long-range scale revealed from this study would improve the understanding of the impacts of Asian dust on the regional/global climate change.