2017年青岛冬季一次云凝结核观测的研究分析

Observational Analysis of Cloud Condensation Nuclei over Qingdao in Winter

2017年1月2—25日在青岛崂山区观测了云凝结核浓度(NCCN)及气溶胶数谱,分析了青岛冬季平均及不同天气下云凝结核浓度及活化率(AR)的特征。观测结果表明:在0.05%~0.6%过饱和度(SS)之间,NCCN变化范围为(1.1~6.4)×103 cm-3;AR变化范围为0.06~0.35。受局地汽车尾气排放的影响,凝结核浓度(NCN)和0.2%~0.6%SS下NCCN的日变化呈双峰型;AR日变化呈双谷型。不同天气之间NCCN及AR差别明显;0.2%SS下,NCCN从高到低的排序依次为雾霾、雾、霾、晴、雨、雪;AR的排序依次为雪、雾、雾霾、霾、雨、晴。而雾霾、霾天的活化率较高,这主要是因为气溶胶中含有相对较高比例的积聚模态颗粒物(大于100nm)。青岛观测期间平均及不同天气下的CCN活化谱均为典型大陆型。

The concentration of cloud condensation nuclei（NCCN）and particle number size distribution at Qingdao were observed from 22 to 25 January,2017 and the variation characteristics of CCN concentration and activation ratio（AR）were analyzed.The results show that the NCCNand AR varied widely.At supersaturation（SS）of 0.05%to 0.6%,the NCCNvariedin the range of 1.1 to 6.4×103 cm-3,the corresponding AR varied in the range of 0.06 to 0.35.The diurnal variation of NCN（concentration of condensation nuclei）and NCCNat SS of 0.2%,0.4% and 0.6% showed bimodal,and the diurnal variation of AR showed double grain.During the observation period,NCCNand AR values at different weather conditions had different characteristics.At SS of 0.2%,the NCCNvalues ranked from larger to smaller corresponding to different weather conditions,i.e.,fog,foggy-haze,haze,less-polluted,snowy and rainy days.AR values showed a different decreasing order,i.e.,from snowy,fog,foggy-haze,haze day,less-polluted to rainy days.The larger AR values on foggy-haze and haze days were mainly because of aerosols containing a relatively high proportion of accumulation mode particles（〉100 nm）.It can be expected an even higher proportion on snowy and fogy days,however,no size distributions of particle number concentration were available for discussion.The average CCN spectrum overall the measurement period and at different weather conditions were the typical continental type.