TY - JOUR
T1 - Reconstructed light extinction coefficients using chemical compositions of PM 2.5 in winter in Urban Guangzhou, China
AU - Tao, Jun
AU - Cao, Jun Ji
AU - Zhang, Ren Jian
AU - Zhu, Lihua
AU - Zhang, Tao
AU - Shi, Si
AU - Chan, Chuen Yu
PY - 2012/3
Y1 - 2012/3
N2 - The objective of this study was to reconstruct light extinction coefficients (b ext) according to chemical composition components of particulate matter up to 2. 5 μm in size (PM 2. 5). PM 2. 5 samples were collected at the monitoring station of the South China of Institute of Environmental Science (SCIES, Guangzhou, China) during January 2010, and the online absorbing and scattering coefficients were obtained using an aethalometer and a nephelometer. The measured values of light absorption coefficient by particle (b ap) and light scattering coefficient by particle (b sp) significantly correlated (R 2 > 0. 95) with values of b ap and b sp that were reconstructed using the Interagency Monitoring of Protected Visual Environments (IMPROVE) formula when RH was <70%. The measured bext had a good correlation (R 2 > 0. 83) with the calculated bext under ambient RH conditions. The result of source apportionment of b ext showed that ammonium sulfate [(NH 4) 2SO 4] was the largest contributor (35. 0%) to b ext, followed by ammonium nitrate (NH 4NO 3, 22. 9%), organic matter (16. 1%), elemental carbon (11. 8%), sea salt (4. 7%), and nitrogen dioxide (NO 2, 9. 6%). To improve visibility in Guangzhou, the effective control of secondary particles like sulfates, nitrates, and ammonia should be given more attention in urban environmental management.
AB - The objective of this study was to reconstruct light extinction coefficients (b ext) according to chemical composition components of particulate matter up to 2. 5 μm in size (PM 2. 5). PM 2. 5 samples were collected at the monitoring station of the South China of Institute of Environmental Science (SCIES, Guangzhou, China) during January 2010, and the online absorbing and scattering coefficients were obtained using an aethalometer and a nephelometer. The measured values of light absorption coefficient by particle (b ap) and light scattering coefficient by particle (b sp) significantly correlated (R 2 > 0. 95) with values of b ap and b sp that were reconstructed using the Interagency Monitoring of Protected Visual Environments (IMPROVE) formula when RH was <70%. The measured bext had a good correlation (R 2 > 0. 83) with the calculated bext under ambient RH conditions. The result of source apportionment of b ext showed that ammonium sulfate [(NH 4) 2SO 4] was the largest contributor (35. 0%) to b ext, followed by ammonium nitrate (NH 4NO 3, 22. 9%), organic matter (16. 1%), elemental carbon (11. 8%), sea salt (4. 7%), and nitrogen dioxide (NO 2, 9. 6%). To improve visibility in Guangzhou, the effective control of secondary particles like sulfates, nitrates, and ammonia should be given more attention in urban environmental management.
KW - chemical species
KW - light extinction coefficients
KW - PM aerosol
UR - https://www.scopus.com/pages/publications/84863415628
U2 - 10.1007/s00376-011-1045-0
DO - 10.1007/s00376-011-1045-0
M3 - 文章
AN - SCOPUS:84863415628
SN - 0256-1530
VL - 29
SP - 359
EP - 368
JO - Advances in Atmospheric Sciences
JF - Advances in Atmospheric Sciences
IS - 2
ER -