(2017) Atmospheric Pollution Research_Factors regulating the distribution of O₃ and NOx at two mountainous sites in Seoul, Korea

Nguyen H.T., Kwon E.E., Kim K.-H., Pandey S.K., Chambers S., Kumar P., Kang C.-H., Cho S.-J., Oh J.-M., Brown R.J.C.

(Elsevier B.V.) Atmospheric Pollution Research ISSN: 13091042 Vol.8 Issue.2 Article No. DOI: 10.1016/j.apr.2016.10.003

The concentrations of ozone (O₃) and nitrogen oxides (NOx) were measured at two mountainous sites in Buk-Han (BH) and Gwan-Ak (GA) and at a reference site in Gwang-Jin (GJ), all in Seoul, South Korea, over a four-year period (2010–2013). The mean concentration (ppb) of NOx was comparable at the mountainous sites (22.9 ± 20.7 (BH) and 20.9 ± 16.9 (GA)) but about half the concentration at the reference site in GJ (47.8 ± 36.4). In contrast, the mean value (ppb) for O₃ at the three sites exhibited a reversed pattern such as 40.2 ± 19.7 at GA, 28.6 ± 15.4 at BH, and 21.8 ± 18.3 at GJ. The concentration of NOx was higher in winter/fall relative to summer/spring at all three sites. Like the clear distinctions observed from the spatial distribution patterns, the seasonal trends conrasted sharply between NOx and O₃. Results of a correlation analysis suggested that the distribution of O₃ was significantly affected by meteorological parameters (e.g., TEMP, UV, and solar radiation). According to a back trajectory analysis, the highest O₃ levels at both mountainous sites were caused by air masses passing over marine areas, while the effects of ozone precursors on ozone concentration were attributed to air masses originating from China and/or the mainland (S. Korea). © 2016 Turkish National Committee for Air Pollution Research and Control

The corresponding author (KHK) acknowledges support made in part by grants from the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST) (No. 2006-0093848) and from the Cooperative Research Program for Agriculture Science & Technology Development (Project title: Study on model development to control odor from hog barn, Project No. PJ010521), Rural Development Administration, Republic of Korea.