南京北郊地区气溶胶光学性质的四季观测研究  

A four⁃season field campaign study of aerosol optical properties in northern suburbs of Nanjing

作　　者：王兴[1,2] 许天峰 马嫣[1,2] 郑军[1,2] WANG Xing;XU Tianfeng;MA Yan;ZHENG Jun(School of Environmental Science and Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China;Jiangsu Key Laboratory of Atmospheric Environment Monitoring&Pollution Control,Nanjing University of Information Science&Technology,Nanjing 210044,China;Shangqiu Meteorological Administration,Shangqiu 476100,China)

机构地区：[1]南京信息工程大学环境科学与工程学院,南京210044 [2]南京信息工程大学,江苏省大气环境与监测污染控制高技术研究重点实验室,南京210044 [3]商丘市气象局,商丘476100

出　　处：《南京信息工程大学学报》2025年第1期138-150,共13页Journal of Nanjing University of Information Science & Technology

基　　金：国家自然科学基金(41975172,42275116)。

摘　　要：本研究于2017年12月—2018年11月进行了针对南京北郊地区气溶胶光学性质研究的外场观测.气溶胶吸收系数和散射系数季节变化由高到低皆为冬季、春季、秋季、夏季,日变化呈双峰型,吸收系数早高峰时间夏季早冬季晚,这是由于不同季节边界层高度和人类生产活动时间发生变化导致的.夏秋两季的平均吸收埃指数(AAE)较高,表明棕碳对气溶胶吸收的贡献较为显著,而春冬两季以黑碳吸收为主.散射埃指数(SAE)春冬季高于夏秋季,气溶胶均以细模态为主,春冬季气溶胶粒径更小.受冬季西北风的影响,西北方向污染物的传输使气溶胶消光系数存在高值.而春夏季东风、东南风方向的本地污染源扩散是导致气溶胶消光系数升高的主要原因.与来自内陆的气团相比,海上的气团传输使气溶胶消光系数降低.当相对湿度小于90%时,气溶胶消光系数与能见度成反比,而当相对湿度大于90%时,能见度普遍小于10 km,与气溶胶消光系数关系不大.春冬季PM2.5中水溶性组分主要为二次源离子,且气溶胶消光系数与硝酸根离子的相关性高于硫酸根离子的相关性,影响气溶胶消光系数的污染物主要来自交通源.与此相反,夏秋季影响气溶胶消光系数的污染物主要来自煤炭燃烧等固定源.In this study,a four⁃season field campaign was conducted from December 2017 to November 2018 to investigate the optical properties of aerosols in the northern suburbs of Nanjing.The seasonal variations of aerosol absorption and scattering coefficients were observed to be highest in winter,followed by spring and autumn,and lowest in summer.The daily variations exhibited a bimodal pattern,with the early peak of absorption coefficient occurring earlier in summer than in winter,which can be attributed to seasonal changes in boundary layer heights and human activity patterns.The average Absorption Ångström Exponent(AAE)was higher in summer and autumn,indicating a more prominent contribution of brown carbon to aerosol absorption,while black carbon dominated in spring and winter.Conversely,the Scattering Ångström Exponent(SAE)was higher in spring and winter than in other seasons,with fine⁃mode aerosols prevailing throughout the year and smaller aerosol particle sizes observed in spring and winter.During winter,the transport of pollutants from the northwest direction under the influence of northwest wind led to high values of aerosol extinction coefficients.In spring and summer,the diffusion of local pollutant emissions from the east and southeast directions was the primary factor contributing to the elevated aerosol extinction coefficients.Compared with the air masses originating from inland,the transport of maritime air masses reduced the aerosol extinction coefficients.When the relative humidity was less than 90%,the aerosol extinction coefficients were inversely proportional to the visibility.However,when the relative humidity exceeded 90%,the visibility was generally less than 10 km and had minimal correlation with the aerosol extinction coefficients.In spring and winter,the water⁃soluble components of PM_(2.5)were primarily secondary source ions,with a stronger correlation between aerosol extinction coefficients and nitrate ions than that of sulfate ions,indicating that transportation⁃related emission s

关 键 词：南京北郊 光学性质 气象参数 化学组分 

分 类 号：X513[环境科学与工程—环境工程] P402[天文地球—大气物理学与大气环境]