Classification of High-Concentration Aerosol Phenomena Using Their Physical Properties in Busan, South Korea

High concentrations of aerosols associated with various meteorological phenomena show different physical characteristics. Because these phenomena are differentiated based on the visibility observed with the eyes, the observation may be unreliable. To investigate aerosol physical properties across various meteorological phenomena and develop an algorithm to classify high-concentration aerosol events, each phenomenon was assessed by analyzing the aerosol number and mass concentrations according to particle size observed with an optical particle counter. Furthermore, the optimal probability density function for each phenomenon was derived using the mass concentration by diameter. In addition, total aerosol mass concentrations, geometric mean particle diameters, and geometric standard deviations were calculated. In the coarse mode, the total mass concentration of the Asian dust case was the highest (16.3 μg·cm−3), whereas in the accumulation mode, the haze value was greatest (22.86 μg·cm−3). Average diameters were 4.41 and 0.41 μm in the coarse and accumulation modes, respectively. A classification algorithm for high-concentration aerosol phenomena was proposed based on the determined physical properties, results of simulating long-distance transport using a backward trajectory model, and meteorological conditions. Among the nine verification cases, all the cases coincided with the observation results of the Korea Meteorological Administration.