Sources of organic aerosols in eastern China: a modeling study with high-resolution intermediate-volatility and semivolatile organic compound emissions

[摘要] Current chemical transport models fail to reproduce boththe concentrations and temporal variations of organic aerosol (OA),especially the secondary organic aerosol (SOA), hindering the identificationof major contribution sources. The fact that precursors ofintermediate-volatility and semivolatile organic compounds (I/SVOCs) arenot included in models has a significant impact on the performance of SOAsimulation. Herein, we establish a high-resolution emission inventory ofI/SVOCs and by incorporating it into the CMAQ model, concentrations,temporal variations, and spatial distributions of POA and SOA originatingfrom different sources in the Yangtze River Delta (YRD) region of China weresimulated. By incorporating I/SVOC emissions into the model, the modeledaverage SOA concentrations in the region increased by 148 %. Significantmodel improvements in the simulations of different OA components weredemonstrated by comparison with comprehensive observation data.Furthermore, spatial and seasonal variations of different sourcecontributions to OA production have been identified. We found that cooking emissionsare predominant sources of POA in the densely populated urban area of theregion. I/SVOC emissions from industrial sources are dominant contributorsto the SOA formation, followed by those from mobile sources. Our resultsindicate that future control measures should be specifically tailored onan intraregional scale based on the different source characteristics to achievethe national goal of continuous improvement in air quality. In addition,local source profiles and emission factors of I/SVOCs, as well as SOAformation mechanisms in the model framework must urgently be updated tofurther improve the model performance and thus the accuracy of sourceidentifications.

[学科分类] 医学（综合）