A Study on the Management Plan of Automatic Measurement Networks Based on Seasonal and Time-of-Day Characteristics of PM10 and PM2.5 in Cheongju City

PM10 and PM2.5 are major sources of air pollution in Korea, particularly during the winter, necessitating systematic management. South Korea operates an automated air quality monitoring network to manage atmospheric conditions, with Cheongju City currently maintaining eight such monitoring stations. In this study, we analyzed hourly measurements from these eight stations in 2024 to understand the characteristics of PM10 and PM2.5 in Cheongju.
Cheongju City, covering an area of 941 km², is a basin-type city located in central Korea. Surrounded by mountains, the city's topographical structure contributes to higher PM10 and PM2.5 concentrations compared to the Korean national average, despite residential areas accounting for less than 30% of the total area.
First, we conducted a Pearson correlation analysis for each monitoring station to identify common contributing pollutants to PM10 and PM2.5 concentrations. For PM10, the correlation between the eight stations ranged from 0.88 to 0.99, while for PM2.5, it ranged from 0.74 to 0.91. These high correlations suggest that the current monitoring network, which measures at hourly intervals, may need to adopt shorter measurement intervals for more precise data.
Seasonal trends indicated that PM10 and PM2.5 concentrations are high in spring and winter but low in summer. The elevated concentrations during spring and winter are attributed to long-range transport from China, as well as domestic emissions from vehicles and heating. Regarding diurnal trends, PM10 concentrations peak during commuting hours due to vehicular traffic, while PM2.5 levels reach their daily minimum between 3:00 PM and 5:00 PM. These findings can be utilized to establish systematic management plans for PM10 and PM2.5 concentrations in Cheongju City.

Acknowledgment:This research was supported by the Particulate Matter Management Specialized Graduate Program through the Korea Environmental Industry & Technology Institute (KEITI), funded by the Ministry of Environment (MOE).