An Analysis of Meteorological Characteristics for Fine Particles on the Korean Peninsula during Wintertime, 2015-2021

Abstract

In order to analyze the characteristics of fine particles on the Korean Peninsula, the synoptic wind field, aerosol optical depth distribution, and surface observation data were used around the East Asia and the Korean Peninsula. In addition, the relationship and relative influence between high-concentration fine particles cases and meteorological variables were evaluated using the General Boosted Machine (GBM) model. In 2020, relatively low concentrations of fine particles appeared due to the weakening of the meridional atmospheric pressure deviation and the weakening of the zonal flow in East Asia. AOD around the Korean Peninsula was high mainly in Incheon and Taean Peninsula, and high AOD was found mainly in the West Sea due to long-range transport from China. In the case of haze or high-concentration fine particles in winter, the PM 2.5 /PM 10 ratio was greater than 0.6, and the ratio increased during long-range transport. In the high-concentration fine particles case, the temperature, wind speed, and boundary layer height (PBLH) were lower than the overall data, and the PM 2.5 /PM 10 ratio was high. When high-concentration cases were analyzed using the GBM model, the fine particles concentration had a high correlation with meteorological and temporal variables. As a result, the relative influence on the fine particles concentration was highest in order of year, week, air temperature, the day of the week, relative humidity, PBLH, hour, wind direction, and wind speed.