Spatio-temporal variation of ozone pollution risk and its influencing factors in China based on Geodetector and Geospatial models.

Ozone (O3) has become the primary pollutant in many cities, and high concentrations of O3 cause significant harm to the ecological environment and human health. This study investigated the spatiotemporal distribution of surface concentrations of ozone over entire China and analyzed the influencing factors based on the geographical detector technique. Moreover, the Pearson correlation analysis was used to analyze the influence of various meteorological factors on ozone concentrations. The results showed that, on the national scale, the daily average O3 concentration in the cities of China in 2019 was 92.441 μg/m3 and the nonattainment rate of daily average ozone was 7.98%. However, the ozone nonattainment rate was 33.33% in heavily polluted regions. The highest O3 concentration was observed in summer, and the lowest was observed in spring. The O3 concentrations in cities across the country showed significant spatial distribution characteristics. Among the five pollutants, the highest correlation was observed between O3 and PM2.5 and the lowest was observed between O3 and SO2. Among the metrological factors, wind speed and solar radiation are the most influencing factors, and showed positive correlation. Moreover, the annual precipitation is negatively correlated with O3-8h concentrations. The methods and findings of this paper can be used as an aid for air pollution control programs in different regions for diminishing the risk of exposure to various air pollutants.