title: Particulate matter pollution over China and the effects of control policies.
abstract: China is one of the regions with highest PM2.5concentration in the world. In this study, we review the spatio-temporal distribution of PM2.5mass concentration and components in China and the effect of control measures on PM2.5concentrations. Annual averaged PM2.5concentrations in Central-Eastern China reached over 100μgm-3, in some regions even over 150μgm-3. In 2013, only 4.1% of the cities attained the annual average standard of 35μgm-3. Aitken mode particles tend to dominate the total particle number concentration. Depending on the location and time of the year, new particle formation (NPF) has been observed to take place between about 10 and 60% of the days. In most locations, NPF was less frequent at high PM mass loadings. The secondary inorganic particles (i.e., sulfate, nitrate and ammonium) ranked the highest fraction among the PM2.5species, followed by organic matters (OM), crustal species and element carbon (EC), which accounted for 6-50%, 15-51%, 5-41% and 2-12% of PM2.5, respectively. In response to serious particulate matter pollution, China has taken aggressive steps to improve air quality in the last decade. As a result, the national emissions of primary PM2.5, sulfur dioxide (SO2), and nitrogen oxides (NOX) have been decreasing since 2005, 2006, and 2011, respectively. The emission control policies implemented in the last decade could result in noticeable reduction in PM2.5concentrations, contributing to the decreasing PM2.5trends observed in Beijing, Shanghai, and Guangzhou. However, the control policies issued before 2010 are insufficient to improve PM2.5air quality notably in future. An optimal mix of energy-saving and end-of-pipe control measures should be implemented, more ambitious control policies for NMVOC and NH3should be enforced, and special control measures in winter should be applied. 40-70% emissions should be cut off to attain PM2.5standard.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Joint Institute for Regional Earth System Science and Engineering, Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA 90095, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhao
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China. Electronic address: shxwang@tsinghua.edu.cn.
authors.forename: Shuxiao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address: fmyang@cigit.ac.cn.
authors.forename: Fumo
authors.initials: F
authors.lastname: Yang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Xing
authors.affiliation: International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4001, Australia. Electronic address: l.morawska@qut.edu.au.
authors.forename: Lidia
authors.initials: L
authors.lastname: Morawska
authors.affiliation: Joint International Research Laboratory of Atmospheric and Earth System Sciences, School of Atmospheric Sciences, Nanjing University, 210023 Nanjing, China.
authors.forename: Aijun
authors.initials: A
authors.lastname: Ding
authors.affiliation: Department of Physics, University of Helsinki, 00014 Helsinki, Finland. Electronic address: markku.kulmala@helsinki.fi.
authors.forename: Markku
authors.initials: M
authors.lastname: Kulmala
authors.affiliation: Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: Veli-Matti
authors.initials: VM
authors.lastname: Kerminen
authors.affiliation: Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: Joni
authors.initials: J
authors.lastname: Kujansuu
authors.affiliation: State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics Chinese Academy of Sciences, 100029 Beijing, China.
authors.forename: Zifa
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
authors.forename: Dian
authors.initials: D
authors.lastname: Ding
authors.affiliation: Key Laboratory of Atmospheric Chemistry, Institute of Atmospheric Compositions, Chinese Academy of Meteorological Sciences, CMA, Beijing 100081, China.
authors.forename: Xiaoye
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
authors.forename: Huanbo
authors.initials: H
authors.lastname: Wang
authors.affiliation: Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
authors.forename: Mi
authors.initials: M
authors.lastname: Tian
authors.affiliation: Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
authors.forename: Tuukka
authors.initials: T
authors.lastname: Petäjä
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
authors.forename: Jingkun
authors.initials: J
authors.lastname: Jiang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
authors.forename: Jiming
authors.initials: J
authors.lastname: Hao
keywords: Chemical speciation; China; Control policies; Metropolitan regions; PM(2.5)