Kim, YJ, Kim, MJ, Lee, KH, Park, SS (2006). "Investigation of carbon pollution episodes using semi-continuous instrument in Incheon, Korea". ATMOSPHERIC ENVIRONMENT, 40(22), 4064-4075.
Hourly measurements of organic and elemental carbon (OC and EC) in fine particles (PM2.5) were conducted at an urban site of Incheon, Korea, between June 2004 and October 2004, using a Sunset Lab semi-continuous carbon field instrument with a continuous-flow non-dispersive infrared (NDIR) detector system. Analyses were performed using the NIOSH thermal-optical transmittance (TOT) protocol. Five-minute black carbon (BC) concentrations were also measured simultaneously using an aethalometer to compare with the thermal and optical EC measurements obtained from a Sunset Lab carbon analyzer. Close inspection of 1-h time-resolved OC and EC measurements reveals many carbon transients, which were mostly attributed to local traffic emissions. In this study, only three distinct carbon pollution episodes are discussed. The first episode was characterized by smoke plumes from forest fires that occurred in southeastern China, which resulted in enhanced OC concentrations. The second episode was strongly associated with regional haze over northeastern China and local stagnation conditions, which lead to highly elevated OC and EC levels throughout the episode. The third episode occurred at the weekend (Saturday and Sunday) was related to broad OC peak and the highest short-term OC excursion over the entire study period. Back trajectory analysis and Moderate Resolution Imaging Spectro-radiometer (MODIS) satellite image data were used to characterize potential source regions for the developed episodes and the transport pathways of the air masses. The measured EC concentrations for the three episodes were strongly associated with the optical EC (R-2 = 0.90-0.98) and BC concentrations (R-2 = 0.93-0.95). The slopes from the relationship between EC and BC varied with the classification of the pollution episodes, ranging from 0.79 to 1.22, suggesting that the attenuation coefficient used for the determination of the BC particle concentrations could depend on the time, sampling location, emission sources of carbon particles, etc. (c) 2006 Elsevier Ltd. All rights reserved.