Research on ozone pollution control strategies for urban agglomerations based on ozone formation sensitivity and emission source contributions.

Despite recent enhancements in China's anthropogenic emission controls, ozone (O) concentrations have continuously increased owing to its nature as a secondary pollutant and the complexities of its production and consumption processes. This study quantified the contributions of urban and sectoral cross-emission sources to O levels and identified the anthropogenic emission sources requiring targeted control. Moreover, O sensitivity tests were conducted to determine optimal reduction ratios for nitrogen oxides (NOx) and volatile organic compounds (VOCs) emissions. The results were used to recommend effective measures for controlling O pollution in the Central Plains urban agglomeration (CPUA). The top 35 cities and sectoral cross-emission sources accounted for 80% of the O concentrations in the region, indicating the need for prioritized management of these sources. To achieve reductions in O concentrations across all cities, it was found that a 10% reduction in total NOx emissions would require a minimum of 18% reduction in VOCs emissions. Our results indicated that the appropriate coordination of reductions in VOCs and NOx emissions reduced the maximum daily 8-h average O (MDA8) concentrations in CPUA by 0.14%-4.78%. Enhancing control measures for prioritized emission sources reduced MDA8 concentrations by 0.78%-7.09%. Furthermore, adjusting the production and emission hours of the industrial sector resulted in a decrease in MDA8 concentrations by 1.10%-12.62%. Overall, our findings indicate that appropriately coordinated reduction of precursor emissions can reduce O levels. Further efforts to mitigate O pollution should include optimizing the timing of emissions from the industrial sector and other major sources of VOCs emissions.