TY - JOUR
T1 - Pinpointing drivers and health effects of exceptional summertime ozone pollution in the Sichuan basin of China in 2022
AU - Yang, Xianyu
AU - Wu, Kai
AU - Wang, Haolin
AU - Wang, Sihui
AU - Zhang, Xiaoling
AU - Yang, Ruihan
AU - Hu, Qin
AU - Xiu, Meng
AU - Jiang, Mengjiao
AU - Ben, Bingzheng
N1 - This work was funded by the National Natural Science Foundation of China (No.42175174), Sichuan High-end Intelligence Introduction Plan (No. 2024JDHJ0020), the project “Investigation of Spatiotemporal Allocation Method of Atmospheric Pollutant Emission Inventory in the Sichuan Basin Based on Volunteered Geographic Data” funded by the Training Program of Innovation and Entrepreneurship for Undergraduates (No.X202510621002).
Publisher Copyright:
© 2025 Elsevier Inc.
PY - 2025/11/15
Y1 - 2025/11/15
N2 - Tropospheric ozone (O3) is a ubiquitous pollutant that is detrimental to human health and ecosystems. The Sichuan Basin (SCB), one of the most populous city clusters in China, has experienced more-intense O3 pollution episodes and longer O3 season with more-frequent stagnant conditions over the past decade. In 2022, the prolonged O3 season featured extremely high levels of O3 and region-wide O3 events were observed, posing significant threats to public health. However, it remains unclear to what extent meteorological fields could contribute to O3 anomaly and to the adverse health impacts from extreme O3 season. Here, we investigate the drivers of extreme summer O3 pollution in 2022 over the SCB using a high-resolution Community Multiscale Air Quality (CMAQ) model in conjunction with surface air quality measurements. Further, the health effects of exposure to high levels of O3 are quantified using the Environmental Benefits Mapping and Analysis Program (BenMAP). Both meteorological reanalysis data and the Weather Research and Forecasting (WRF) modeling revealed extreme heat featured by persistent heatwaves in the study period, which significantly perturbed daytime photochemical reactions and primed the landscape for elevating O3. Sensitivity experiments with fixed anthropogenic emissions indicate that unfavorable meteorology and subsequent enhancements in biogenic emissions substantially contributed to O3 anomaly. Importantly, this unprecedented O3 season resulted in 48285 all-cause deaths due to long-term exposure, which is 8064 higher than the same period in 2019 and significantly overtake previous recognition. CMAQ simulations point to that O3 elevation could be partially offset by concurrent 50 % emission reductions on nitrogen oxides (NOx) and volatile organic compounds (VOCs), leading to avoided deaths of 2660. This work highlights the underestimated O3-related mortality burden and pinpoints the necessity of stringent emission regulations toward O3 mitigation in basin topography.
AB - Tropospheric ozone (O3) is a ubiquitous pollutant that is detrimental to human health and ecosystems. The Sichuan Basin (SCB), one of the most populous city clusters in China, has experienced more-intense O3 pollution episodes and longer O3 season with more-frequent stagnant conditions over the past decade. In 2022, the prolonged O3 season featured extremely high levels of O3 and region-wide O3 events were observed, posing significant threats to public health. However, it remains unclear to what extent meteorological fields could contribute to O3 anomaly and to the adverse health impacts from extreme O3 season. Here, we investigate the drivers of extreme summer O3 pollution in 2022 over the SCB using a high-resolution Community Multiscale Air Quality (CMAQ) model in conjunction with surface air quality measurements. Further, the health effects of exposure to high levels of O3 are quantified using the Environmental Benefits Mapping and Analysis Program (BenMAP). Both meteorological reanalysis data and the Weather Research and Forecasting (WRF) modeling revealed extreme heat featured by persistent heatwaves in the study period, which significantly perturbed daytime photochemical reactions and primed the landscape for elevating O3. Sensitivity experiments with fixed anthropogenic emissions indicate that unfavorable meteorology and subsequent enhancements in biogenic emissions substantially contributed to O3 anomaly. Importantly, this unprecedented O3 season resulted in 48285 all-cause deaths due to long-term exposure, which is 8064 higher than the same period in 2019 and significantly overtake previous recognition. CMAQ simulations point to that O3 elevation could be partially offset by concurrent 50 % emission reductions on nitrogen oxides (NOx) and volatile organic compounds (VOCs), leading to avoided deaths of 2660. This work highlights the underestimated O3-related mortality burden and pinpoints the necessity of stringent emission regulations toward O3 mitigation in basin topography.
KW - All-cause death
KW - Complex terrain
KW - Exposure assessment
KW - Heatwave
KW - Mortality burden
KW - Ozone
UR - https://www.scopus.com/pages/publications/105011952781
UR - https://www.sciencedirect.com/science/article/pii/S0013935125017177?via%3Dihub
U2 - 10.1016/j.envres.2025.122465
DO - 10.1016/j.envres.2025.122465
M3 - Journal article
AN - SCOPUS:105011952781
SN - 0013-9351
VL - 285, Part 3
JO - Environmental Research
JF - Environmental Research
M1 - 122465
ER -
