Various air pollutants have been measured at Tokchok Island since April 1999. The Island is situated in the Yellow Sea, about 50 km from Incheon. This study was undertaken to help understand the levels of air pollution and their distribution characteristics over the Yellow Sea. The mass concentrations and chemical compositions, of total suspended particulates (TSP) and fine particles (PM2.5), measured up until March 2000 are discussed in this paper. The overall average mass concentrations for TSP and PM2.5 were about 37.2 and 18.7 μg m-3, respectively, which were similar to, or lower than, those observed at other background sites in Kangwha and Taean, Korea. However, they are much lower than those observed at Qingdao in China. The low mass concentrations and major anthropogenic ion concentrations in aerosols collected at Tokchok Island show that local sources are not dominant. The estimated average fractions of non-sea-salt (nss) sulfate to total sulfate concentrations of TSP and PM2.5 are > 98% for each. This would suggest that sulfate is mainly affected by anthropogenic sources. If we consider the average mass ratio of PM2.5 to TSP, the mass fractions of anthropogenic species to PM2.5, and the molar ratio of nss sulfate to total nitrate, it may be possible to infer that a part of the anthropogenic species measured at Tokchok Island is transported from China. The characteristics of neutralization of nss sulfate, and the particle sizes of major ions, are also discussed.
Bibliographical noteFunding Information:
This work was supported by the Ministry of Science and Technology, Korea, for Yellow Sea Research under grant 98-LO-01-01-A-03. Y.P. Kim was supported by the Climate Environment System Research Center, an SRC Program funded by the Korea Science and Engineering Foundation. We gratefully acknowledge Korea Telecom for providing the facility at the Tokchok Island station.
- Atmospheric aerosol
- Chemical composition
- Yellow Sea