Spatiotemporal Characteristics of Winter PM2.5 in Hubei Province in Recent Ten Years and Constraints in Wuhan, based on CCM Exploration

Abstract Under the influence of meteorological conditions such as atmospheric circu-lation and topographic conditions, regional transport of PM2.5 occurs and affects air quality. In this paper, the causal relationship between PM2.5 concentrations in other prefectural cities in Hubei Province, China and Wuhan was empirically investigated by using the Convergent Cross Mapping (CCM) with air quality monitoring data from the winter of 2015 to the winter of 2023 in each city in Hubei Province. It is found that there is a significant nonlinear weak coupling between PM2.5 concentrations in other prefectures in Hubei Province and Wuhan, and four groups of PM2.5 concentrations are causally correlated with each other with medium and strong correlations based on the 0.2 significance level test. Combined with the atmospheric circulation analysis, the regional transmission speed and direction of PM2.5 are affected by seasons.