Pollution Characteristics of Ambient Fine Particulate Matters at Mt. Halla-1100 and Gosan Sites in Jeju Island

Abstract

Ambient fine particulate matters of PM10 and PM2.5 were collected at the Mt. Halla-1100 site (a site at an altitude of 1100 meters on Mt. Halla) and the Gosan site, which comprise a typical mountainous site and coastal background site, respectively, on Jeju Island. The major water-soluble ionic species of these sites were analyzed. The average mass concentrations of PM10 and PM2.5 at the Mt. Halla-1100 site were 0.59 times lower and 0.78 times lower, respectively, than those at the Gosan site. The composition ratios of the major secondary air pollutants (nss-SO42-, NO3-, and NH4+) of PM10 and PM2.5 were 86.2% and 93.2%, respectively, at the Mt. Halla-1100 site, while those at the Gosan site were 67.7% and 87.2%, respectively. These results show the comparatively larger contributions at the Mt. Halla-1100 site. The principal component analysis reveals that the main affecting factors for the ionic compositions of PM10 and PM2.5 particles at both sites are the anthropogenic emission sources, especially the comparative influence of organic acids at the Mt. Halla-1100 site, and the marine sources at the Gosan site. Based on the neutralization factors, the fine particulate matters were acidified mainly by sulfuric and nitric acids, and the neutralization was relatively caused by calcium carbonate in PM10 particles and ammonia in PM2.5 particles. The clustered back trajectory analyses indicated that the major ionic concentrations of PM10 and PM2.5 comparatively increased when the airflow moved from continental China and the Korean Peninsula. The polluting influence from China was apparent in the upper planetary boundary layer (PBL) compared with that at ground level. Key Words: PM10, PM2.5, Mt. Halla-1100 site, Gosan site, Planetary Boundary Layer (PBL)