Characteristics of Black Carbon Aerosol during the Chinese Lunar Year and Weekdays in Xi’an, China

Atmosphere

Qiyuan Wang¹  Suixin Liu¹  Yaqing Zhou¹  Junji Cao¹  Yongming Han¹  Haiyan Ni¹  Ningning Zhang¹  Rujin Huang¹ 

[1] Key Laboratory of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China; E-Mails:

关键词: refractory black carbon;    size distribution;    mixing state;    carbon monoxide;   

DOI  :  10.3390/atmos6020195

来源: mdpi

【 摘 要 】

Black carbon (BC) aerosol plays an important role in climate forcing. The net radiative effect is strongly dependent on the physical properties of BC particles. A single particle soot photometer and a carbon monoxide analyser were deployed during the Chinese Lunar Year (CLY) and on weekdays at Xi’an, China, to investigate the characteristics of refractory black carbon aerosol (rBC). The rBC mass on weekdays (8.4 μg·m⁻³) exceeds that during the CLY (1.9 μg·m⁻³), presumably due to the lower anthropogenic emissions during the latter. The mass size distribution of rBC shows a primary mode peak at ~205 nm and a small secondary mode peak at ~102-nm volume-equivalent diameter assuming 2 g·cm⁻³ in void-free density in both sets of samples. More than half of the rBC cores are thickly coated during the CLY (f_BC = 57.5%); the percentage is slightly lower (f_BC = 48.3%) on weekdays. Diurnal patterns in rBC mass and mixing state differ for the two sampling periods, which are attributed to the distinct anthropogenic activities. The rBC mass and CO mixing ratios are strongly correlated with slopes of 0.0070 and 0.0016 μg·m⁻³·ppbv⁻¹ for weekdays and the CLY, respectively.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.