Articles | Volume 26, issue 17
https://doi.org/10.5194/acp-26-12231-2026
© 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-26-12231-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Resolving systematic errors in sulfate source apportionment: a field-validated kinetic isotope fractionation framework
Zhaobing Guo
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Suqian University, Suqian 223800, China
Xuexue Bai
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Qiwei Ai
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Zizheng Xu
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Shangshun Ma
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Jiayu Gu
School of Chemical Engineering and Materials, Changzhou Institute of Technology, Changzhou 213032, China
Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
Qingjun Guo
CORRESPONDING AUTHOR
Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
Related authors
Ziyan Guo, Keding Lu, Pengxiang Qiu, Mingyi Xu, and Zhaobing Guo
Atmos. Chem. Phys., 24, 2195–2205, https://doi.org/10.5194/acp-24-2195-2024, https://doi.org/10.5194/acp-24-2195-2024, 2024
Short summary
Short summary
The formation of secondary sulfate needs to be further explored. In this work, we simultaneously measured sulfur and oxygen isotopic compositions to gain an increased understanding of specific sulfate formation processes. The results indicated that secondary sulfate was mainly ascribed to SO2 homogeneous oxidation by OH radicals and heterogeneous oxidation by H2O2 and Fe3+ / O2. This study is favourable for deeply investigating the sulfur cycle in the atmosphere.
Ziyan Guo, Keding Lu, Pengxiang Qiu, Mingyi Xu, and Zhaobing Guo
Atmos. Chem. Phys., 24, 2195–2205, https://doi.org/10.5194/acp-24-2195-2024, https://doi.org/10.5194/acp-24-2195-2024, 2024
Short summary
Short summary
The formation of secondary sulfate needs to be further explored. In this work, we simultaneously measured sulfur and oxygen isotopic compositions to gain an increased understanding of specific sulfate formation processes. The results indicated that secondary sulfate was mainly ascribed to SO2 homogeneous oxidation by OH radicals and heterogeneous oxidation by H2O2 and Fe3+ / O2. This study is favourable for deeply investigating the sulfur cycle in the atmosphere.
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Short summary
We refined the traditional isotopic mathematical model, originally predicated on the assumption of exhaustive sulfur dioxide oxidation, to account for the incomplete oxidation processes observed in our field campaigns. By constraining this modified framework with in-situ isotopic data, we demonstrated that conventional models, which overlook this partial oxidation, tend to significantly underestimate sulfate source contributions during the summer.
We refined the traditional isotopic mathematical model, originally predicated on the assumption...
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