China’s SO <sub>2</sub> emission reductions enhance atmospheric ozone–driven sulfate aerosol production in East Asia
Abstract
Reduction of China’s SO 2 emissions has been found to nonlinearly decrease the atmospheric sulfate (SO 4 2− ) aerosol concentrations in East Asia. Compared to Europe and North America, the lower effectiveness of SO 4 2− reduction in East Asia suggested much effects of “acidity-sensitive” feedback mechanisms in this high anthropogenic emission region, which have not been yet examined. In this work, we investigated these feedback mechanisms in East Asia through long-term measurements of the mass-independent oxygen-17 anomaly (Δ 17 O) in sulfate aerosols, machine learning and Community Multiscale Air Quality (CMAQ) model. As China’s emissions reduced, the atmospheric acidity decreased, enhancing the ozone-driven oxidation of S(IV) and production efficiency of sulfate formation. This explained the weaker declining SO 4 2− concentrations than SO 2 emissions. By the evidence from observed Δ 17 O in non-sea-salt sulfate (Δ 17 O-nss-SO 4 2− ) and CMAQ simulations, the highly enhanced contributions of S(IV)+O 3 to sulfate driven by reduced SO 2 emissions explained the low effectiveness of SO 4 2− reduction in East Asia. Additionally, the decreases of acidity by substantial NH 3 emissions are projected to continue until 2050, limiting SO 4 2− reduction effectiveness. Thus, we highlighted that global control of both SO 2 and NH 3 emissions are needed to efficiently mitigate the sulfate-related climate and pollution, especially in high NH 3 emission region, such as East Asia.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (15)
Yu-Chi Lin
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Yan Zhao
Yan-Lin Zhang
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Yihang Hong
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Shohei Hattori
International Center for Isotope Effects Research, Nanjing University
Syuichi Itahashi
Research Institute for Applied Mechanics, Kyushu University
Mei-Yi Fan
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Feng Xie
Zhu-Yu Zhao
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Mingyuan Yu
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Fang Cao
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Rongshuang Xu
Jiangsu Key Laborartory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Joint International Research Laboratory of Climate and Environment Change, School of Ecology and Applied Meteorology, Nanjing University of Information Science and Technology
Jianghanyang Li
Institute of Arctic and Alpine Research, University of Colorado
Kimitaka Kawamura
Chubu Institute for Advanced Study, Chubu University
Mark H. Thiemens
Department of Chemistry and Biochemistry, University of California