Characteristics and Meteorological Effects of Ozone Pollution in Spring Season at Coastal City, Southeast China

Surface ozone (O-3) pollution has become one of the top environmental issues in recent years around the world and can be influenced by meteorological processes on multiple scales. Understanding the meteorological mechanism and contributions of O-3 pollution is of great importance for O-3 mitigation. In this study, we explored the impacts of meteorological conditions on O-3 concentrations in a coastal city in Southeast China, with a particular focus on O-3 pollution episodes inspringtime. A significant increase in the O-3 pollution ratefrom 2015 to 2020 was observed (41.7% year(-1)) and the seasonal characteristics of O-3 concentrations showed a two-peak pattern. We selected 12 pollution episodes during the springtime of 2015 to 2020 and identified four dominant synoptic weather patterns (SWPs) that could cause O-3 pollution. The local meteorological conditions and vertical dynamic structures under different SWPs were analyzed. The results showed that high O-3 levels tend to be associated with high temperature, weak wind, low relative humidity, and deep vertical sinking motion. We also established a quantitative linkage between the O-3 values and meteorological factors. Based on meteorological conditions, 60.8 similar to 80.8% of the variation in O-3 can be explained.