2009年夏季黄山云雾水化学特征及来源分析

Analyses of chemical characteristic in fog/cloud water and source at Mount Huangshan in summer 2009

利用09年夏季在黄山光明顶气象站采集的25个云雾水样本及气象站常规资料,分析了云雾过程雾水的化学特征、污染来源与微物理特性.结果表明,观测期间云雾水呈弱酸性,平均值pH值为6.4,主要的离子浓度由大到小排列为:SO42->NH4+>Ca2+>NO3->Na+>Cl-,表明二次污染物对黄山云雾水的贡献较大.统计分析显示,各云雾过程中雾水组分变化,主要缘于不同云雾过程中污染源与海洋源的贡献率不同.结合后向轨迹进一步分析显示,影响气团主要来源于海洋和周边地区,不同气团影响下雾水离子组分及云雾微物理特征差别明显.

Twenty-five fog/cloud water samples were collected at the weather station at summit of Mount Huangshan in summer 2009.Chemical characteristics,source of pollutants and microphysical properties of fog/cloud are analyzed based on the surface observational data at Guangmingding Station and the fog/cloud samples.Results show that the fog/clouds at Mount Huangshan are weakly acid,with the mean value of pH at 6.4.The descending order of concentration of major ionic species in fog/clouds is： SO4^2-NH4^＋Ca^2＋NO3^-Na^＋Cl^-,indicating that secondary pollutants contributed greatly to fog/cloud.Due to the differences in contribution from regional pollutant sources and marine sources,soluble components varied greatly in different fog/cloud events.Backward trajectory analysis reveals that fog/cloud air mass is originated from marine and surrounding area.The ionic composition,microphysical properties and parameters of fog/cloud are significantly differences in various air masses.