Analysis of Meteorological Factors and Transport Sources of Different Ozone Pollution Events in Foshan

doi:10.3969/j.issn.1007-6190.2025.04.011

Abstract：To understand the key influencing factors of different ozone (O3) pollution events in the Foshan area, this study used O3 concentration data from national environmental monitoring stations in Foshan from 2017 to 2023, along with corresponding meteorological data and GDAS data, to analyze the meteorological factors and transport sources of different O3 pollution events. The results showed that: (1) O3 pollution was the most severe in 2019 and the lightest in 2020. (2) When the average temperature was between 25–32 ℃, the maximum temperature was between 28–36 ℃, and the sunshine duration was between 8–11 hours, the frequency of processes with longer pollution duration was higher; when the relative humidity was between 60%–68% and the atmospheric pressure was between 1005–1013 hPa, the frequency of moderate or heavier pollution and pollution lasting ≥3 days was higher; when the wind speed was between 1–2 m·s-1, the frequency of moderate or heavier pollution was the highest. (3) Under different O3 pollution levels and durations, air mass transport mainly occurred over medium and short distances, with trajectories mainly coming from the south, southeast, northeast, and north directions. During periods of moderate or heavier pollution, the 8-hour O3 concentration at the 90th percentile from the southeast direction was the highest ((227.5±69.5) μg·m-3). (4) Potential source areas for light pollution were mainly concentrated in the Pearl River Delta, northern Guangdong, southern Hunan, and southern Jiangxi, covering the potential source areas for moderate or heavier pollution. As the duration of pollution increased, the potential source areas became more concentrated in the eastern Pearl River Delta to northern Guangdong, southeastern Jiangxi, and southwestern Hunan.