Ozone Pollution and Transmission Characteristics in Shantou City

doi:10.3969/j.issn.1007-6190.2025.03.014

Abstract：To understand the pollution sources of ozone (O3) in Shantou City, this study analyzed the O3 mass concentration data from the national control atmospheric environmental quality monitoring stations in Shantou City from 2015 to 2023 to explore the characteristics of O3 pollution. Based on the backward trajectory model (HYSPLIT), the distribution of backward air flow trajectories was calculated. Through cluster analysis, the transport paths and potential source areas of external pollutants in Shantou City were analyzed. The results show that O3 has become the main pollutant affecting the air quality in Shantou City. The most severe O3 pollution seasons are autumn and spring, while the O3 mass concentration almost does not exceed the standard in winter. The correlation coefficient between O3 mass concentration and relative humidity is the highest throughout the year and in polluted months, followed by the number of daylight hours. When the daily average pressure is between 1002-1020 hPa, the number of daylight hours exceeds 9 hours, the humidity is between 45%-65%, and the average wind speed is between 1.0-2.5 m·s-1, the O3 mass concentration exceeds the standard significantly. Northeastern airflow is the main transport channel in spring and autumn, and it contributes the most to O3 concentration in spring; western and northern airflow contributes the most to O3 and NO2 mass concentrations in autumn; northern airflow contributes the most to SO2 mass concentration in spring and autumn; eastern airflow contributes the most to NO2 mass concentration in spring.