Articles | Volume 26, issue 7
https://doi.org/10.5194/acp-26-5085-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-5085-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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16 Apr 2026
Research article | Highlight paper |
| 16 Apr 2026
| 16 Apr 2026
Drivers and implications of declining fossil fuel CO2 concentrations in Chinese cities revealed by radiocarbon measurements
Pingyang Li
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Boji Lin
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
Zhineng Cheng
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Jing Li
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Duohong Chen
CORRESPONDING AUTHOR
Environmental Key Laboratory of Regional Air Quality Monitoring, Ministry of Ecology and Environment, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, People's Republic of China
Tao Zhang
Environmental Key Laboratory of Regional Air Quality Monitoring, Ministry of Ecology and Environment, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, People's Republic of China
Run Lin
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Sanyuan Zhu
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Jun Liu
Environmental Key Laboratory of Regional Air Quality Monitoring, Ministry of Ecology and Environment, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, People's Republic of China
Yujun Lin
Environmental Key Laboratory of Regional Air Quality Monitoring, Ministry of Ecology and Environment, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, People's Republic of China
Shizhen Zhao
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangcai Zhong
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Zhenchuan Niu
State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, People's Republic of China
Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710061, People's Republic of China
Ping Ding
State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Gan Zhang
CORRESPONDING AUTHOR
State Key Laboratory of Advanced Environmental Technology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
Guangdong Key Laboratory of Environmental Protection and Resources Utilization, and Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the Environment, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China
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Jiao Tang, Jiaqi Wang, Guangcai Zhong, Hongxing Jiang, Yangzhi Mo, Bolong Zhang, Xiaofei Geng, Yingjun Chen, Jianhui Tang, Congguo Tian, Surat Bualert, Jun Li, and Gan Zhang
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This article provides a combined EEM–PARAFAC and statistical analysis method to explore how excitation–emission matrix (EEM) chromophores influence BrC light absorption in soluble organic matter. The application enables us to deduce that BrC absorption is mainly dependent on longer-emission-wavelength chromophores largely associated with biomass burning emissions. This method promotes the application of EEM spectroscopy and helps us understand the light absorption of BrC in the atmosphere.
Ye Kuang, Shan Huang, Biao Xue, Biao Luo, Qicong Song, Wei Chen, Weiwei Hu, Wei Li, Pusheng Zhao, Mingfu Cai, Yuwen Peng, Jipeng Qi, Tiange Li, Sihang Wang, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 21, 10375–10391, https://doi.org/10.5194/acp-21-10375-2021, https://doi.org/10.5194/acp-21-10375-2021, 2021
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We found that organic aerosol factors with identified sources perform much better than oxidation level parameters in characterizing variations in organic aerosol hygroscopicity, and secondary aerosol formations associated with different sources have distinct effects on organic aerosol hygroscopicity. It reveals that source-oriented organic aerosol hygroscopicity investigations might result in more appropriate parameterization approaches in chemical and climate models.
Mingfu Cai, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Shan Huang, Yuwen Peng, Zelong Wang, Haobo Tan, Fei Li, Hanbin Xu, Duohong Chen, and Jun Zhao
Atmos. Chem. Phys., 21, 8575–8592, https://doi.org/10.5194/acp-21-8575-2021, https://doi.org/10.5194/acp-21-8575-2021, 2021
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This study investigated the contribution of new particle formation (NPF) events to the number concentration of cloud condensation nuclei (NCCN) and its controlling factors in the Pearl River Delta region. The results show that the surfactant effect can decrease the critical diameter and significantly increase the NCCN during the NPF event. In addition, the growth rate is founded to be the most important controlling factor that affects NCCN for growth of newly-formed particles to the CCN sizes.
Xuewu Fu, Chen Liu, Hui Zhang, Yue Xu, Hui Zhang, Jun Li, Xiaopu Lyu, Gan Zhang, Hai Guo, Xun Wang, Leiming Zhang, and Xinbin Feng
Atmos. Chem. Phys., 21, 6721–6734, https://doi.org/10.5194/acp-21-6721-2021, https://doi.org/10.5194/acp-21-6721-2021, 2021
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TGM concentrations and isotopic compositions in 10 Chinese cities showed strong seasonality with higher TGM concentrations and Δ199Hg and lower δ202Hg in summer. We found the seasonal variations in TGM concentrations and isotopic compositions were highly related to regional surface Hg(0) emissions, suggesting land surface Hg(0) emissions are an important source of atmospheric TGM that contribute dominantly to the seasonal variations in TGM concentrations and isotopic compositions.
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Editorial statement
This study presents the first multi-city observational assessment of fossil-fuel CO₂ emissions in major and mid-sized Chinese cities using Δ(¹⁴C) and δ(¹³C). The measurements reveal substantial declines in fossil-fuel CO₂ concentrations, consistent with documented reductions in coal consumption, increased reliance on natural gas, and notable improvements in combustion efficiency. However, the observed decreases are larger than those reported by bottom‑up emission inventories, suggesting that current inventories may systematically underestimate real-world CO₂ mitigation. These findings hold important policy implications for evaluating the effectiveness of China’s clean‑air measures and for advancing accurate urban emissions monitoring.
This study presents the first multi-city observational assessment of fossil-fuel CO₂ emissions...
Short summary
Our study indicates fossil fuel CO2 (CO2ff) reductions in Chinese megacities via atmospheric Δ(14CO2) and δ(13CO2) measurements, driven by coal-to-gas transitions and combustion efficiency improvement. The 24-year record show steeper declined urban RCO/CO2ff ratios than inventory estimates, implying underestimation of efficiency improvements and CO reductions. Integrating top-down observations with inventories is critical to track policy-driven emission shifts and optimize co-benefit strategies.
Our study indicates fossil fuel CO2 (CO2ff) reductions in Chinese megacities via atmospheric...
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