Dynamics of Urban Atmospheric Conditions under Emission Mitigation Pathways

Siying Wang; Yuejia Wu; Tianjia Zhang; Jiashun Hui; Chuanzhe Lin; Wanran Tu; Kewei Feng; Patrick Qi

doi:10.71222/ce2cay39

Authors

Siying Wang Choate Rosemary Hall, Wallingford, CT, 06492, USA Author
Yuejia Wu Wuhan Britain-China School, Wuhan, Hubei, 430033, China Author
Tianjia Zhang Ningbo Foreign Language School, Ningbo, Zhejiang, 315121, China Author
Jiashun Hui The Experimental High School Attached to Beijing Normal University, Beijing, 100032, China Author
Chuanzhe Lin Hamden Hall Country Day School, Hamden, CT, 06517, United Sates Author
Wanran Tu The High School Affiliated to Renmin University of China, Beijing, China Author
Kewei Feng International Education Division, The Experimental High School Attached to BNU, Beijing 100032, China Author
Patrick Qi Beijing National Day School, Beijing 100011, China Author

DOI:

https://doi.org/10.71222/ce2cay39

Keywords:

WRF-CMAQ, deep decarbonization, non-linear response, synergistic control, Yangtze River Delta

Abstract

Rapid urbanization and industrialization have led to complex atmospheric pollution characterized by coincident high levels of PM_2.5 and ozone (O₃) . This study establishes a high-resolution "Emission-Meteorology-Chemistry" simulation system using the WRF-CMAQ model to evaluate the air quality response to three mitigation pathways—structural adjustment (S1), end-of-pipe control (S2), and deep decarbonization (S3)—in the Yangtze River Delta (YRD) region. The results indicate that while all scenarios reduce PM_2.5, the Deep Decarbonization (S3) pathway provides the most significant co-benefits, reducing urban PM_2.5 by 58.5% to 32.1μg/m³. In contrast, O₃ exhibits a strong non-linear response; the S2 scenario triggers a "Chemical Penalty," increasing peak MDA8 ozone by +5.2% due to the weakened NO_x titration effect in VOC-limited urban cores. Integrated Process Rate (IPR) and EKMA analysis reveal that only the S3 pathway, through synchronous NO_x and VOC_s reductions (>60%), successfully crosses the "EKMA Ridgeline" and suppresses the atmospheric oxidizing capacity (AOC) by slowing the HO_x radical propagation rate by 84.8%. The findings suggest that achieving carbon neutrality goals is a prerequisite for overcoming the ozone bottleneck. This study proposes a "Spatially Differentiated and Temporally Dynamic" control strategy, prioritizing VOC_s abatement in urban cores and strict management of industrial emissions during peak photochemical hours to achieve synergistic pollution and carbon reduction.

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