Articles | Volume 17, issue 1
Atmos. Chem. Phys., 17, 77–92, 2017
Atmos. Chem. Phys., 17, 77–92, 2017

Research article 03 Jan 2017

Research article | 03 Jan 2017

Modeling biogenic and anthropogenic secondary organic aerosol in China

Jianlin Hu1, Peng Wang2, Qi Ying1,2, Hongliang Zhang3, Jianjun Chen4, Xinlei Ge1, Xinghua Li5, Jingkun Jiang6, Shuxiao Wang6, Jie Zhang7,9, Yu Zhao8,9, and Yingyi Zhang10 Jianlin Hu et al.
  • 1Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Jiangsu Engineering Technology Research Center of Environmental Cleaning Materials, Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing 210044, China
  • 2Zachry Department of Civil Engineering, Texas A&M University, College Station, TX 77843-3136, USA
  • 3Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA 77803, USA
  • 4Air Quality Planning and Science Division, California Air Resources Board, 1001 I Street, Sacramento, CA 95814, USA
  • 5School of Space & Environment, Beihang University, Beijing, 100191, China
  • 6State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
  • 7Jiangsu Provincial Academy of Environmental Science, 176 North Jiangdong Rd., Nanjing, Jiangsu 210036, China
  • 8State Key Laboratory of Pollution Control & Resource Reuse and School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China
  • 9Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing, Jiangsu 210044, China
  • 10School of Environment and Energy, South China University of Technology, Guangzhou, China

Abstract. A revised Community Multi-scale Air Quality (CMAQ) model with updated secondary organic aerosol (SOA) yields and a more detailed description of SOA formation from isoprene oxidation was applied to study the spatial and temporal distribution of SOA in China in the entire year of 2013. Predicted organic carbon (OC), elemental carbon and volatile organic compounds agreed favorably with observations at several urban areas, although the high OC concentrations in wintertime in Beijing were under-predicted. Predicted summer SOA was generally higher (10–15 µg m−3) due to large contributions of isoprene (country average, 61 %), although the relative importance varies in different regions. Winter SOA was slightly lower and was mostly due to emissions of alkane and aromatic compounds (51 %). Contributions of monoterpene SOA was relatively constant (8–10 %). Overall, biogenic SOA accounted for approximately 75 % of total SOA in summer, 50–60 % in autumn and spring, and 24 % in winter. The Sichuan Basin had the highest predicted SOA concentrations in the country in all seasons, with hourly concentrations up to 50 µg m−3. Approximately half of the SOA in all seasons was due to the traditional equilibrium partitioning of semivolatile components followed by oligomerization, while the remaining SOA was mainly due to reactive surface uptake of isoprene epoxide (5–14 %), glyoxal (14–25 %) and methylglyoxal (23–28 %). Sensitivity analyses showed that formation of SOA from biogenic emissions was significantly enhanced due to anthropogenic emissions. Removing all anthropogenic emissions while keeping the biogenic emissions unchanged led to total SOA concentrations of less than 1 µg m−3, which suggests that manmade emissions facilitated biogenic SOA formation and controlling anthropogenic emissions would result in reduction of both anthropogenic and biogenic SOA.

Short summary
An annual simulation of secondary organic aerosol (SOA) concentrations in China with updated SOA formation pathways reveals that SOA can be a significant contributor to PM2.5 in major urban areas. Summer SOA is dominated by emissions from biogenic sources, while winter SOA is dominated by anthropogenic emissions such as alkanes and aromatic compounds. Reactive surface uptake of dicarbonyls throughout the year and isoprene epoxides in summer is the most important contributor.
Final-revised paper