title: Quantifying the effect of organic aerosol aging and intermediate-volatility emissions on regional-scale aerosol pollution in China.
abstract: Secondary organic aerosol (SOA) is one of the least understood constituents of fine particles; current widely-used models cannot predict its loadings or oxidation state. Recent laboratory experiments demonstrated the importance of several new processes, including aging of SOA from traditional precursors, aging of primary organic aerosol (POA), and photo-oxidation of intermediate volatility organic compounds (IVOCs). However, evaluating the effect of these processes in the real atmosphere is challenging. Most models used in previous studies are over-simplified and some key reaction trajectories are not captured, and model parameters are usually phenomenological and lack experimental constraints. Here we comprehensively assess the effect of organic aerosol (OA) aging and intermediate-volatility emissions on regional-scale OA pollution with a state-of-the-art model framework and experimentally constrained parameters. We find that OA aging and intermediate-volatility emissions together increase OA and SOA concentrations in Eastern China by about 40% and a factor of 10, respectively, thereby improving model-measurement agreement significantly. POA and IVOCs both constitute over 40% of OA concentrations, and IVOCs constitute over half of SOA concentrations; this differs significantly from previous apportionment of SOA sources. This study facilitates an improved estimate of aerosol-induced climate and health impacts, and implies a shift from current fine-particle control policies.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
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.
authors.forename: Shuxiao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Center for Atmospheric Particle Studies, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Donahue
authors.affiliation: Civil and Environmental Engineering, University of California, Davis, CA 95616, USA.
authors.forename: Shantanu H
authors.initials: SH
authors.lastname: Jathar
authors.affiliation: Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Huang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Wu
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
authors.affiliation: Center for Atmospheric Particle Studies, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA.
authors.forename: Allen L
authors.initials: AL
authors.lastname: Robinson
mesh_terms: D000336:Aerosols / Q000032:analysis* / Q000737:chemistry; D000393:Air Pollutants / Q000737:chemistry*; D001272:Atmosphere / Q000737:chemistry; D002681:China; D003198:Computer Simulation; D004784:Environmental Monitoring / Q000379:methods; D005843:Geography; D008962:Models, Theoretical; D009930:Organic Chemicals / Q000737:chemistry*; D010084:Oxidation-Reduction; D052638:Particulate Matter / Q000737:chemistry*; D013997:Time Factors; D001335:Vehicle Emissions / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000737:chemistry; D014835:Volatilization
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D009930:Organic Chemicals; D052638:Particulate Matter; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds