[Characteristics and Influence of Atmospheric VOCs in Ozone Formation Potential in Suburb of Shanghai During Summer].

To help promote ozone pollution control and understand the influence of atmospheric volatile organic compounds （VOCs） on O₃ during the summer ozone pollution season, the analyses of variation characteristics and ozone formation potentials of VOCs during O₃ pollution episodes were carried out based on the online monitoring data of VOCs and O₃, as well as the meteorological parameters in the suburban site of Shanghai. The impact of key meteorological factors and regional transport on O₃ and VOCs was investigated. The results showed that the mean value of atmospheric φ（VOCs） during summer in the suburban area of Shanghai was （20.91 ± 9.82）×10^-9, and the largest proportion of each component was with alkanes and OVOCs, both of which were 30.2%. The mean value of φ（VOCs） on O₃ polluted days was （23.84 ± 9.69）×10^-9, which was 28.1% higher than that on clean days. The OFP of VOCs on polluted days was 126.92 μg·m^-3, which was 31.9% higher than that on clean days. The contribution of olefins to OFP accounted for a significant increase, and species such as propylene and acetone were the most significant compared to on clean days, indicating that these components and species need to be the focus of mitigation. The variation characteristics of the ratio of ethane to acetylene （E/E） and the ratio of m/p-xylene to ethylbenzene（X/E） indicated that there was a significant regional transport influence of the summer air masses in the suburban area of Shanghai, and it occurred mainly in the afternoon and at night. The results of the pollution rose diagram and the backward trajectory of air masses indicated that air masses from the south and southwest directions had the greatest influence on the transport of VOCs in suburban Shanghai. In particular, it is necessary to focus on controlling olefin and OVOCs from southern air masses and aromatic hydrocarbons from southwestern air masses.