Atmos. Chem. Phys. Discuss., 11, 13867-13910, 2011
www.atmos-chem-phys-discuss.net/11/13867/2011/
doi:10.5194/acpd-11-13867-2011
© Author(s) 2011. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP.
Springtime carbon episodes at Gosan background site revealed by total carbon, stable carbon isotopic composition, and thermal characteristics of carbonaceous particles
J. Jung and K. Kawamura
Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan

Abstract. In order to investigate the carbon episodes at Gosan background super-site (33.17° N, 126.10° E) in East Asia during spring of 2007 and 2008, total suspended particles (TSP) were collected and analyzed for particulate organic carbon, elemental carbon, total carbon (TC), total nitrogen (TN), and stable carbon isotopic composition (δ13C) of TC. The carbon episodes at the Gosan site were categorized as long-range transported anthropogenic pollutant (LTP) from Asian continent, Asian dust (AD) accompanying with LTP, and local pollen episodes. The stable carbon isotopic composition of TC (δ13CTC) was found to be lowest during the pollen episodes (range: −26.2 ‰ to −23.5 ‰, avg.: −25.2 ± 0.9 ‰), followed by the LTP episodes (range: −23.5 ‰ to −23.0 ‰, avg.: −23.3 ± 0.3 ‰) and the AD episodes (range: −23.3 to −20.4 %, avg.: −21.8 ± 2.0 ‰). The δ13CTC of the airborne pollens (−28.0 ‰) collected at the Gosan site showed value similar to that of tangerine fruit (−28.1 ‰) produced from Jeju Island. Based on the carbon isotope mass balance equation and the TN and TC regression approach, we found that ∼40–45 % of TC in the TSP samples during the pollen episodes was attributed to airborne pollens from Japanese cedar trees planted around tangerine farms in Jeju Island. The δ13C of citric acid in the airborne pollens (−26.3 ‰) collected at the Gosan site was similar to that in tangerine fruit (−27.4 ‰). The negative correlation between the citric acid-carbon/TC ratios and δ13CTC were obtained during the pollen episodes. These results suggest that citric acid emitted from tangerine fruit may be adsorbed on the airborne pollens and then transported to the Gosan site. Based on the thermal evolution pattern of organic aerosols during the carbon episodes, we found that organic aerosols originated from East China are more volatile on heating and are more likely to form pyrolized organic carbon than the pollen-enriched organic aerosols and organic aerosols originated from Northeast China. Since thermal evolution patterns of organic aerosols are highly influenced by their molecular weight, they can be used as additional information on the formation of secondary organic aerosols during the long-range atmospheric transport and the source regions of organics.

Citation: Jung, J. and Kawamura, K.: Springtime carbon episodes at Gosan background site revealed by total carbon, stable carbon isotopic composition, and thermal characteristics of carbonaceous particles, Atmos. Chem. Phys. Discuss., 11, 13867-13910, doi:10.5194/acpd-11-13867-2011, 2011.
 
Search ACPD
Discussion Paper
    XML
    Citation
    Final Revised Paper
    Share