Investigations of Transported and Local Emissions on Particle Compositions in Korea

Received: August 20, 2012
Revised: July 28, 2013
Accepted: July 28, 2013
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2012.08.0218  

Cite this article:
Cayetano, M.G., Hopke, P.K., Lee, K.H., Jung, J., Batmunkh, T., Lee, K. and Kim, Y.J. (2014). Investigations of Transported and Local Emissions on Particle Compositions in Korea. Aerosol Air Qual. Res. 14: 793-805. https://doi.org/10.4209/aaqr.2012.08.0218

ABSTRACT

The synoptic meteorological patterns, aerosol optical thickness (AOT) and changes in the chemical composition of aerosol particles are indicators that allow the study of the effects of emissions on air quality. These approaches have been applied to two sets of intensive campaign measurement data in Gwangju, Korea, allowing the identification of long-range transported (LRT) and local emission impacts in spring of 2008 and 2010. Prefrontal air masses originating from polluted regions of the Asian continent influenced the particulate properties on March 12, 13, 27, April 12–13, and May 7, 2008, resulting in SO₄^–2 concentrations of 44.1 µg/m³, 44.6 µg/m³, 26.4 µg/m³, 21.9 µg/m³ and 26.4 µg/m³, respectively, compared to a local baseline concentration of 8.5 µg/m³. Air masses affected by mixed burning (LRT-MB) arrived in Gwangju between April 23 to 27, 2008 and influenced the particulate organic carbon (OC) concentrations by as much as 20.0 µgC/m³. Pollution events in 2010 have been classified into three classes: sulfate-nitrate (S-N) dominant, chloride-enriched (Cl^–) and mixed burning influenced (Local MB) emissions. From the diurnal patterns of SO₄^–2 and NO₃^–, their concentrations were found to be lowest at midday and highest in the evening, with their chemical transformation reactions consistent with known processes that lead to the formation of NH₄NO₃. Cl-enriched emissions not related to sea salt and biomass burning emissions were observed on various occasions; a strong correlation (adjusted R² = 0.96) between excess NH₄⁺ and Cl^– exists for the pooled cases. The data suggested contributions from local municipal solid waste combustion and biomass burning. Overall analysis of ionic balance suggests that the LRT particles may provide an excess SO₄^–2. The neutralizing capacity of NH₃ for local emissions was demonstrated from the detection of sufficient amount of NH₄⁺ that has been reacted with Cl^–.

Keywords: PM2.5; Atmospheric aerosols; Air pollution; Emission characterization; Biomass burning; Urban air quality; Secondary aerosol; Municipal solid waste burning