title: Apportioning and locating nonmethane hydrocarbon sources to a background site in Korea.
abstract: Nonmethane hydrocarbons (NMHCs) measured between April 2004 and March 2005 at a background monitoring site on Sukmo Island, Korea were analyzed to identify and apportion NMHC sources. A total of 7694 samples and 35 NMHC species were analyzed. Positive matrix factorization (PMF), applied to identify and apportion the sources of NMHCs, resolved six sources: two fuel evaporative sources (36.3%), solvent sources (25.4%), mixed sources of vehicle exhaust and combustion (22.8%), petrochemical sources (9.6%), and biogenic sources (5.4%). During the summer, the largest contributors to ozone formation were biogenic sources (48.9% and 79.7% by maximum incremental reactivity and propene-equivalent concentration, respectively), which were situated locally, and secondary sources included solvent sources (22.2% and 7.4%) and fuel evaporative sources (15.6% and 8.2%). For evaporative-1 sources composed of long-lived alkanes, the potential source contribution function (PSCF) technique using 48 h back trajectories revealed oil and gas fields in China as potential source areas of fresh "regional" air masses. In addition, the PSCF results for evaporative-2 sources and a long-lived marker species of vehicle exhaust/combustion sources showed that the NMHC mixing ratio in Sukmo, South Korea was enhanced by long-range transport from the Shandong area in China.
authors.affiliation: Department of Environmental Health, Graduate School of Public Health, Seoul National University, Gwanak-gu, Seoul, 151-742, South Korea.
authors.forename: Eunhwa
authors.initials: E
authors.lastname: Choi
authors.forename: Jong-Bae
authors.initials: JB
authors.lastname: Heo
authors.forename: Seung-Muk
authors.initials: SM
authors.lastname: Yi
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D056911:Democratic People's Republic of Korea; D004784:Environmental Monitoring; D006838:Hydrocarbons / Q000032:analysis* / Q000737:chemistry; D008956:Models, Chemical; D010126:Ozone / Q000032:analysis / Q000138:chemical synthesis
chemical_list: D000393:Air Pollutants; D006838:Hydrocarbons; D010126:Ozone