title: Relative impact of emissions controls and meteorology on air pollution mitigation associated with the Asia-Pacific Economic Cooperation (APEC) conference in Beijing, China.
abstract: The Beijing government and its surrounding provinces implemented a series of measures to ensure haze-free skies during the 22(nd) Asia-Pacific Economic Cooperation (APEC) conference (November 10(th)-11(th), 2014). These measures included restrictions on traffic, construction, and industrial activity. Twelve hour measurements of the concentration and composition of ambient fine particulate matter (PM2.5) were performed for 5 consecutive months near the APEC conference site before (September 11(th)-November 2(nd), 2014), during (November 3(rd)-12(th), 2014) and after (November 13(th), 2014-January 31(st), 2015). The measurements are used in a positive matrix factorization model to determine the contributions from seven sources of PM2.5: secondary aerosols, traffic exhaust, industrial emission, road dust, soil dust, biomass burning and residual oil combustion. The source apportionment results are integrated with backward trajectory analysis using Weather Research and Forecast (WRF) meteorological simulations, which determine the relative influence of new regulation and meteorology upon improved air quality during the APEC conference. Data show that controls are very effective, but meteorology must be taken into account to determine the actual influence of the controls on pollution reduction. The industry source control is the most effective for reducing concentrations, followed by secondary aerosol and biomass controls, while the least effective control is for the residual oil combustion source. The largest reductions in concentrations occur when air mass transport is from the west-northwest (Ulanqab). Secondary aerosol and traffic exhaust reductions are most significant for air mass transport from the north-northwest (Xilingele League) origin, and least significant for northeast transport (Chifeng via Tangshan conditions). The largest reductions of soil dust, biomass burning, and industrial source are distinctly seen for Ulanqab conditions and least distinct for Xilingele League.
authors.affiliation: College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Civil and Environmental Engineering Department, University of Wisconsin-Madison, Madison, WI 53705, USA; Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: James Jay
authors.initials: JJ
authors.lastname: Schauer
authors.affiliation: Department of Earth and Atmospheric Sciences, Saint Louis University, St. Louis, MO 63108, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: de Foy
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Shandong 250100, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Guo
authors.affiliation: College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Huairou Eco-Environmental Observatory, Chinese Academy of Sciences, Beijing 101408, China; CAS Center for Excellence in Urban Atmospheric Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address: yxzhang@ucas.ac.cn.
authors.forename: Yuanxun
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000392:Air Movements; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis / Q000517:prevention & control*; D000068476:Beijing; D004784:Environmental Monitoring; D052638:Particulate Matter / Q000032:analysis*; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions
keywords: APEC; Control measures; Meteorology; PM(2.5); PMF; Source apportionment