Seasonal variations of mass absorption efficiency of elemental carbon in PM_(2.5) in urban Guangzhou of South China  

作　　者：Chenglei Pei Yunfei Wu Jun Tao Leiming Zhang Tao Zhang Runqi Zhang Sheng Li 

机构地区：[1]State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China [2]CAS Center for Excellence in Deep Earth Science,Guangzhou 510640,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center,Guangzhou 518049,China [5]Key Laboratory of Middle Atmosphere and Global Environment Observation,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China [6]Institute for Environmental and Climate Research,Jinan University,Guangzhou 510632,China [7]Air Quality Research Division,Science and Technology Branch,Environment and Climate Change Canada,Toronto,Canada [8]Guangdong Ecological and Environmental Monitoring Center,Guangzhou 510308,China

出　　处：《Journal of Environmental Sciences》2023年第11期83-92,共10页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.41775155,41875160 and 41475119).

摘　　要：This study investigates seasonal variations of mass absorption efficiency of elemental carbon(MAE_(EC))and possible influencing factors in urban Guangzhou of South China.Mass concentrations of elemental carbon(EC)and organic carbon(OC)in PM_(2.5) and aerosol absorption coefficient(b_(ap))at multi-wavelengths were simultaneously measured in four seasons of 2018-2019 at hourly resolution by a semi-continuous carbon analyzer and an aethalometer.Seasonal average mass concentrations of EC were in the range of 1.36-1.70μgC/m^(3) with a lower value in summer than in the other seasons,while those of OC were in the range of 4.70–6.49μgC/m^(3) with the lowest value in summer and the highest in autumn.Vehicle exhaust from local traffic was identified to be the predominant source of carbonaceous aerosols.The average aerosol absorption Angstrom exponents(AAE)were lower than 1.2 in four seasons,indicating EC and b_(ap) were closely related with vehicle exhaust.Seasonal MAE EC at 550 nm was 11.0,8.5,10.4 and 11.3 m^(2)/g in spring,summer,autumn,and winter,respectively.High MAE EC was related with the high mass ratio of non-carbonaceous aerosols to EC and high ambient relative humidity.

关 键 词：Vehicle exhaust Non-carbonaceous aerosols Absorption enhancement Relative humidity 

分 类 号：X513[环境科学与工程—环境工程]