Chen, Xi, Wang, Nan, Wang, Gang, Wang, Zaihua, Chen, Hui, Cheng, Chunlei, Li, Mei, Zheng, Lianming, Wu, Liqing, Zhang, Qianhua, Tang, Mei, Huang, Bo, Wang, Xuemei, and Zhou, Zhen
Tropospheric ozone (O3) pollution is becoming the primary obstacle to the improvement of air quality in China, especially in the Pearl River Delta (PRD) region. Because O3pollution episodes are closely related to synoptic weather patterns (SWPs), historical episodes (from 2006 to 2019) were classified according to SWPs using the Lamb‐Jenkinson method. Monitoring network and weather reanalysis data, emission inventories, and satellite retrievals were used to investigate the spatiotemporal characteristics and influences of O3pollution. It was found that easterly (P_E), anticyclone (P_A), and typhoon‐related (P_NE) SWPs accounted for 75% of all O3pollution episodes. In the PRD, the O3formation mechanism showed clear differences under different SWPs, which were affected by local emissions under P_A, whereas regional transmission dominated under P_E and P_NE. The O3peak concentration was strongly associated with temperature, solar radiation, and shifting of the sea‐land breeze. A delayed shift of land to sea breeze caused by SWPs often caused the O3peak to appear in the late afternoon. Finally, stepwise regression was used to explain individual meteorological parameters contributing to O3formation. It was found that the formation of O3pollution under P_E and P_NE was associated with increases in temperature and radiation, while P_A was mainly affected by the increase of the overnight accumulation of O3. This study advances our knowledge of the formation mechanism of O3pollution and provides scientific support for effective O3pollution control. In recent years, tropospheric ozone (O3) has become an important air pollutant hindering the improvement of air quality in the Pearl River Delta (PRD) region, China. In spite of the complicated nonlinear relationship between O3and its precursor, the variable synoptic weather patterns (SWPs), which control O3production and transportation, bring troubles to O3pollution control. To explore the influence of SWPs on spatiotemporal characteristics and internal causes of O3pollution, we objectively classified the historical episodes (from 2006 to 2019) and analyzed the meteorological factors, transmission paths of pollutants, and O3pollution characteristics under different SWPs. It was found that easterly (P_E), anticyclone (P_A), and typhoon‐related (P_NE) SWPs were the most common O3pollution weather systems. Generally, P_A mainly features local emission pollution, the cyclone circulation is conducive to the accumulation of ozone at night, resulting in high O3levels on the next day. P_E and P_NE tend to cause regional transmission pollution with unfavored meteorological conditions like the increase in temperature and radiation. Based on the findings, we constructed a multivariate linear regression model which can accurately predict the MDA8 O3in advance. This study provides a scientific support for O3pollution control. Historical O3episodes in the Pearl River Delta are classified according to synoptic weather patterns (SWPs)The O3formation mechanism shows clear differences under different SWPs and the dominant parameters are diagnosedThe anticyclone pattern is sensitive to overnight ozone accumulation, while the other patterns are sensitive to meteorological parameters Historical O3episodes in the Pearl River Delta are classified according to synoptic weather patterns (SWPs) The O3formation mechanism shows clear differences under different SWPs and the dominant parameters are diagnosed The anticyclone pattern is sensitive to overnight ozone accumulation, while the other patterns are sensitive to meteorological parameters