국토지리학회지 ISSN:1225-3766(Print) THE GEOGRAPHICAL JOURNAL OF KOREA

While PM₁₀ concentrations in Busan Metropolitan City have decreased over the past 15 years, their intra-city variations still persist due to local environmental characteristics of the city. It has been confirmed that the average PM₁₀ level spatially varies depending on various urban conditions such as industrial, commercial, and residential areas. Asymmetric daily cycles were observed in PM₁₀ concentrations, where PM₁₀ levels increased rapidly in the morning hours, but the rate of decrease in the afternoon hours was relatively lower throughout the city. A cluster analysis based on the daily and weekly PM₁₀ data showed that the city’s air-quality monitoring points were divided into four main clusters caused primarily by their PM₁₀ levels. The highest PM₁₀ concentration was observed in the industrial or agricultural cluster, where PM₁₀ concentrations increased faster in the morning, and the daily peak concentration occurred earlier than the other sites. The city’s specific strategies for air-quality improvement may be established when the spatially varying contributing factors on PM₁₀ levels such as the type of industrial sectors, green space distributions, proportions of primary and secondary pollutants are further evaluated at the local level.