摘要
瓦里关大气本底监测站位于青藏高原东北部,几乎不受局地人为活动的影响,可反映较大空间尺度的大气成分信息.为研究人为活动对本底大气成分产生的影响,在瓦里关站点利用七波段黑碳仪(AE33)对2019年1—12月的黑碳(BC,black carbon)气溶胶浓度进行连续观测,获得了其季节和日变化特征,并使用黑碳仪模型和拉格朗日大气传输模式FLEXPART(Flexible Particle Dispersion Model)对BC来源类型和源区分布进行了分析.结果显示:黑碳气溶胶平均浓度为(332±308)ng·m^(-3);受污染排放和气象因子的季节性变化的影响,BC在春季、夏季、秋季、冬季的平均值分别为(446±343)、(297±223)、(233±209)、(352±382)ng·m^(-3);BC日变化峰值分别出现在凌晨(3:00)和中午(13:00),凌晨出现的峰值由污染长距离输送引起,中午出现的峰值与局地山谷风环流有关.中午的峰值是由BC黑碳来源解析结果显示化石燃料燃烧对BC浓度的贡献占主导地位,全年平均贡献率为68%.生物质燃烧的贡献率在冬季明显升高,达到了40%±1%;FLEXPART源区结果表明离采样点距离近的西宁、兰州对瓦里关BC影响最大,四季平均贡献均超过100 ng·m^(-3);印度半岛在秋季和冬季对瓦里关的影响较大;在春季和秋季,我国中部和西南部地区也存在BC的源区,但贡献值较小.
Mt.Waliguan(WLG)is located in the northeastern part of the Qinghai-Tibet Plateau,is completely isolated from local anthropogenic emissions.Thus,WLG is an appropriate site to explore the background atmospheric chemical characteristics on a regional scale.To study the influence of human activities on black carbon(BC)at WLG,the BC mass concentrations were observed by the seven-channel Aethalometer(AE33)from January to December 2019.Apart from the diurnal and seasonal variations,the emission sources and potential source regions of BC were also quantified by the Aethalometer model combining with Flexible Particle(FLEXPART)Dispersion Model.The results showed that average concentration of BC during the sampling period was(332±308)ng·m^(-3);and average BC were(446±343)、(297±223)、(233±209)、(352±382)ng·m^(-3)in spring,summer,autumn and winter,respectively.Combustion of fossil fuel was a dominant source of BC at WLG,contributing approximately 68%to the total BC masses.The enhanced fractions(40%±1%)of biomass burning to BC was found in the winter.Using the FLEXPART model,we found that Xining and Lanzhou,were the potential source regions of BC at WLG,with an average contribution of more than 100 ng·m^(-3)during the entire sampling period.In addition,the long-range transported sources from the Indian Peninsula,central and southwestern China also contributed non-neglected portions to BC at WLG.
作者
阿布都热夏提·阿布力米提
于鸣媛
曹芳
任磊
王剑琼
章炎麟
Abudurexiati·Abulimiti;YU Mingyuan;CAO Fang;REN Lei;WANG Jianqiong;ZHANG Yanlin(Yale-NUIST Center on Atmospheric Environment,International Joint Laboratory on Climate and Environment Change(ILCEC),Nanjing University of Information Science&Technology,Nanjing 210044;School of Applied Meteorology,Nanjing University of Information Science&Technology,Nanjing 210044;China Global Atmosphere Watch Baseline Observatory,Xining 810001)
出处
《环境科学学报》
CAS
CSCD
北大核心
2022年第12期311-321,共11页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No.41977185,42107123)
南京信息工程大学人才启动经费。
关键词
黑碳
瓦里关
污染特征
源解析
源区分布
black carbon(BC)
Mt.Waliguan
characteristic
source apportionment
source distribution
