HR: 0800h
AN: A51A-0024 [Abstracts]
TI: Temporal Variations of Elemental Carbon in Beijing
AU: * Kondo, Y
EM: y.kondo@atmos.rcast.u-tokyo.ac.jp
AF: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1
Komaba, Meguro-ku, Tokyo, 153-8904, Japan
AU: Han, S
EM: han@atmos.rcast.u-tokyo.ac.jp
AF: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1
Komaba, Meguro-ku, Tokyo, 153-8904, Japan
AU: Takegawa, N
EM: takegawa@atmos.rcast.u-tokyo.ac.jp
AF: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1
Komaba, Meguro-ku, Tokyo, 153-8904, Japan
AU: Miyazaki, Y
EM: yuzom@atmos.rcast.u-tokyo.ac.jp
AF: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1
Komaba, Meguro-ku, Tokyo, 153-8904, Japan
AU: Hu, M
EM: minhu@pku.edu.cn
AF: Peking University, Beijing 100871, Beijing, 100871, China
AU: Lin, P
EM: lppku@163.com
AF: Peking University, Beijing 100871, Beijing, 100871, China
AU: Deng, Z
EM: dzqpku@gmail.com
AF: Peking University, Beijing 100871, Beijing, 100871, China
AU: Zhao, Y
EM: yjzhao@ucdavis.edu
AF: University of California, Davis, One Shields Avenue, Davis, CA 95616, United States
AB:
Concentrations of elemental carbon (EC) in fine mode (PM2.5) were measured at Peking University in Beijing,
China in four seasons from November 2005 to October 2007. The EC concentrations were measured every one-
hour with a semi-continuous thermal-optical analyzer. Carbon monoxide (CO) and carbon dioxide (CO2)
concentrations were measured using non-dispersive infrared absorption (NDIR) instruments with a time
resolution of 1 minute. The EC and CO concentrations decreased with the increase in the wind speed (WS). The
correlations of EC with CO and CO2 were generally compact throughout the measurement period and the slopes
of the EC-CO and EC-CO2 correlations (ĢEC/ĢCO and ĢEC/ĢCO2) are therefore useful parameters in
investigating EC sources. The average EC concentrations for each season ranged between about 6 and 8
ƒÊg/m3. CO showed minimum values of about 1.1 ppmv in spring-summer and maximum of about 2.1 ppmv in
winter. On calm days (WS < 2m/s), the average EC concentrations started to increase at around 1800 LT and
continued to increase until around 0200 LT. The ĢEC/ĢCO ratios also showed similar diurnal patterns except
for winter, when they showed little diurnal variation. These results suggest that there are strong EC source in
Beijing during the nighttime, possibly from diesel vehicles. The high CO in winter indicates strong source of CO
due to domestic heating and this lowered the ĢEC/ĢCO ratios.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting