title: Long-term variation of black carbon and PM2.5 in Beijing, China with respect to meteorological conditions and governmental measures.
abstract: Black carbon (BC) and PM2.5 were studied for nine years from 2005 to 2013 in the Beijing urban area. The overall weekly average mass concentrations of BC and PM2.5 were 4.3 and 66.8 μg/m³. PM2.5 annual means of the nine years are around 2 times of the standard (GB3095-2012) in China, and are 5-7 times higher than the WHO standard. The Beijing Olympic Games in 2008 was a milestone to mitigate aerosol pollution. Temporal distribution of BC shows a distinct declining trend, and annual mean mass concentrations of PM2.5 after 2008 were lower than those before 2008 but increased from 2011 to 2013. Wind rose plots show that high BC concentrations are usually associated with low wind speed of northeastern or southwestern winds, generally causing poor visibility. Governmental mitigation measures such as traffic restriction despite increased motor vehicle numbers and gasoline consumption and industry relocation with declining consumption of coal and coke were successful in reducing BC emissions. Annual mean of BC was reduced by 38% in 2013 compared to 2005. However, BC contamination in Beijing is still severe when compared to other urban areas around the world.
authors: Institute of Applied Geosciences, Working Group for Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany. Electronic address: yuan.chen@kit.edu.
authors: Yuan
authors: Y
authors: Chen
authors: Institute of Applied Geosciences, Working Group for Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany.
authors: Nina
authors: N
authors: Schleicher
authors: Air Quality Department, Research Center Human Biometeorology, German Meteorological Service, 79104, Freiburg i. Br., Germany.
authors: Mathieu
authors: M
authors: Fricker
authors: School of the Earth Sciences and Resources, China University of Geosciences, 100083, Beijing, China.
authors: Kuang
authors: K
authors: Cen
authors: School of the Earth Sciences and Resources, China University of Geosciences, 100083, Beijing, China.
authors: Xiu-Li
authors: XL
authors: Liu
authors: Air Quality Department, Research Center Human Biometeorology, German Meteorological Service, 79104, Freiburg i. Br., Germany.
authors: Uwe
authors: U
authors: Kaminski
authors: School of the Earth Sciences and Resources, China University of Geosciences, 100083, Beijing, China.
authors: Yang
authors: Y
authors: Yu
authors: School of the Earth Sciences and Resources, China University of Geosciences, 100083, Beijing, China.
authors: Xue-Fang
authors: XF
authors: Wu
authors: Institute of Applied Geosciences, Working Group for Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany; Institute of Geography and Geoecology, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany; Institute of Mineralogy, Technische Universität Bergakademie Freiberg, Brennhausgasse 14, 09596, Freiberg, Germany.
authors: Stefan
authors: S
authors: Norra
mesh_terms: D000336:Aerosols; D000388:Air / Q000592:standards; D000393:Air Pollutants / Q000032:analysis*; D000068476:Beijing; D003247:Conservation of Natural Resources / Q000331:legislation & jurisprudence / Q000379:methods; D004784:Environmental Monitoring / Q000331:legislation & jurisprudence / Q000379:methods*; D033161:Government Regulation; D007221:Industry; D008685:Meteorological Concepts; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D053260:Soot / Q000032:analysis*; D014919:Wind
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D052638:Particulate Matter; D053260:Soot
keywords: Black carbon; Megacity; PM(2.5); Temporal distribution; Urban aerosol