AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Seasonal Variation of Organic Aerosols at Urban Gwangju, Korea Measured With Aerosol Mass Spectrometer
Seungyong Lee, JIYEON PARK, Kihong Park, Aerosol Technology and Monitoring Lab., GIST
Abstract Number: 772 Working Group: Urban Aerosols
Abstract Atmospheric aerosols are strongly associated with earth’s radiation budget, cloud formation, human health, and visibility impairment. Organic aerosols constitute a significant mass fraction of the submicron aerosols, and understanding of organic aerosols is necessary to reduce the largest uncertainties in aerosol effects on radiative forcing and cloud formation and to better control the air quality. In this study, seasonal and diurnal variations of organics in the submicron particles was determined by using an Aerosol Mass Spectrometer (Aerodyne Inc, USA) in fall (8/30/2011-9/19/2011), winter (12/19/2011-12/30/2011), spring (5/16/2012-5/24/2012), and summer (7/23/2012-8/6/2012) at urban Gwangju, Korea. Furthermore, the organic aerosols were further classified into hydrocarbon-like organic aerosol (HOA), less-volatile oxygenated organic aerosol (LV-OOA), and semi-volatile oxygenated organic aerosol (SV-OOA) components by using a Positive Matrix Factorization (PMF) method (PMF2 software) (Paatero, 2004a; Paatero 2004b). It was found that organics were the most dominant chemical species in the total aerosol mass loadings at the urban Gwangju, and the average mass concentrations of organics were 4.7 +- 1.8 µg/m3, 6.3 +- 1.8 µg/m3, 4.0 +- 1.8 µg/m3, 4.9 +- 1.8 µg/m3 in the fall, winter, spring, and summer, respectively. The HOA was the most dominant in the organic aerosols in winter, while the OOA was the highest in summer. The LV-OOA was somewhat higher than SV-OOA in summer. Diurnal variation showed that the HOA had a pronounced diurnal pattern with increased concentration in the morning and evening times, while the OOA increased in the afternoon. More data analysis is in progress, which will be discussed in the presentation.