Carbonaceous species in fine particles at the background sites in Korea between 1994 and 1999

Organic carbon (OC) and elemental carbon (EC) in fine particles (PM2.5) at two background sites, Kosan and Kangwha in Korea were measured during inten sive field studies between 1994 and 1999. Fine particles were collected on pre-fired quartz filters in a low-volume sampler and analyzed using the sel ective thermal oxidation method with MnO2 catalyst. The OC and EC concentra tions at Kosan located at western tip of Cheju Island in southern Korea are lower than those at Kangwha located at western coastal area in mid-Korean peninsula. Still, the OC concentrations at Kosan are generally higher than those at other background areas in Japan and USA. The EC concentrations at Kosan are lower than ol comparable to those at other background areas. The total carbon (TC, sum of OC and EC) to EC ratio values at both sites were h igher than those at other background areas in Japan and USA. At Kosan, the OC and EC concentrations when air parcels were from southern China were hig her than those when air parcels were coming from northern China. However, a t Kangwha, the differences were statistically not clear since most air parc els were from northern China. Except when air parcels were from the North P acific during summer, the OC and EC concentrations are well correlated indi cating that both OC and EC share the same emission/transport characteristic s. From the gaseous hydrocarbon data and the OC and EC relationship, it was found that during summer local biogenic emissions of OC might be significa nt at Kosan. (C) 2000 Elsevier Science Ltd. All rights reserved.