The Trend of the Concentrations of the Criteria Pollutants over Seoul

Abstract

The trends of the criteria air pollutants` concentrations over Seoul are reviewed, relative contributions of major sources are discussd, and directions for future air quality management are suggested. It was shown that the yearly average concentrations of the criteria air pollutants except nitrogen dioxide and ozone have decreased significantly over the last three decades. Though the concentration of nitrogen dioxide has not decreased, the concentration of has decreased significantly. The major reason for the reduction of the criteria air pollutants has been strict government regulations such as establishment of strict emission standards and switch to cleaner fuels. However, it is not clear the major reason (s) for the reduction of the concentration. It is suggested that to further reduce the concentrations of secondary air pollutants such as ozone and , understanding the major chemical pathways for them is essential. In addition, influence from outside Seoul should be quantified and effectively controlled.