Substantial reductions in black carbon from both fossil fuels and biomass burning during China’s Clean Air Action
Abstract
Black carbon (BC) aerosols exacerbate air pollution and climate warming, but their climatic impacts and sources are poorly constrained by bottom–up emission inventories (EIs). China’s Clean Air Action (CAA), which was launched in 2013, provides an excellent opportunity for investigating interannual variations in source contributions and validate the accuracy of EIs. Here, we present an 11-y (2008–2018) record of the BC concentration and its source-diagnostic radiocarbon ( 14 C) and stable carbon isotope ( 13 C) signatures at a receptor site in the Pearl River Delta (PRD) region, South China. The results revealed that the implementation of the CAA (2014–2018) led to a 41% reduction in the BC concentration compared with that in the preaction period (2008–2013). There is a large and systemic discrepancy over the whole period in the contribution of biomass burning to BC in South China between predictions from technology-based EIs (4 to 9%) and these source-diagnostic dual-isotopic fingerprints of actual ambient aerosols (21 to 32%). Observational constraints by source-diagnostic δ 13 C/Δ 14 C isotope measurements revealed that the reduction in biomass burning contributed 22% to the decrease in BC associated with the CAA, whereas predictions from EIs assigned a much smaller fraction. These results emphasize the need for observation-based source diagnostics of changing BC emission sources. Detailed source apportionment using independent δ 13 C/Δ 14 C isotope methodology is crucial for refining air pollution control strategies and improving the accuracy of models used for assessing the air quality and climate effects of BC in China and elsewhere.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (20)
Junwen Liu
Institute for Environmental and Climate Research, College of Environment and Climate, Jinan University
Fan Jiang
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences
Qiongqiong Wang
Division of Environment and Sustainability, Hong Kong University of Science and Technology
Gan Zhang
Jun Li
Weihua Chen
Ping Ding
State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences
Sanyuan Zhu
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences
Zhineng Cheng
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences
Xiangyun Zhang
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences
Qinge Sha
Institute for Environmental and Climate Research, College of Environment and Climate, Jinan University
Zhijiong Huang
Institute for Environmental and Climate Research, College of Environment and Climate, Jinan University
Xin Yuan
Junyu Zheng
Sustainable Energy and Environment Thrust, Hong Kong University of Science and Technology
Yanlin Zhang
School of Materials Science and Engineering, Zhejiang University
Caiqing Yan
Environment Research Institute, Shandong University
Chongguo Tian
CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences
Yingjun Chen
Research Center for Analytical Sciences, Frontiers Science Center for New Organic Matter, and Key Laboratory of Biosensing and Molecular Recognition, College of Chemistry
Jian Zhen Yu
Division of Environment and Sustainability, Hong Kong University of Science and Technology
Örjan Gustafsson
Department of Environmental Science and the Bolin Centre for Climate Research, Stockholm University