Volume 14, No. 3, April 2014, Pages 793-805 PDF(3.36 MB)
Investigations of Transported and Local Emissions on Particle Compositions in Korea
Mylene G. Cayetano1, Philip K. Hopke2, Kwon H. Lee3, Jinsang Jung1, Tsatsral Batmunkh1, Kwangyul Lee1, Young J. Kim1
1 School of Environmental Science and Engineering, Gwangju Institute of Science and Technology, 500712, Gwangju, Korea
2 Center for Air Resources Engineering and Science Clarkson University, P.O. Box 5708 Potsdam, NY 13699-5708, USA
3 Department of Satellite Geoinformatics Engineering, Kyungil University, Buhori 33, Hayangeub, Gyungsan, Korea
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–.
PM2.5; Atmospheric aerosols; Air pollution; Emission characterization; Municipal solid waste burning; Biomass burning; Urban air quality; Secondary aerosol.