Key features of new particle formation events at background sites in China and their influence on cloud condensation nuclei

• Published in: Frontiers of environmental science & engineering 2016-10, Vol.10 (5), p.107-117, Article 5
• Main Authors: SHEN, Xiaojing, SUN, Junying, ZHANG, Xiaoye, ZHANG, Yangmei, ZHANG, Lu, FAN, Ruxia
• Format: Article
• Language: English
• Subjects: Atmospheric conditions; Cloud condensation nuclei; Condensates; Condensation nuclei; Diameters; Earth and Environmental Science; Environment; Formation rate; F事件; Growth rate; New particle formation; Regional background; Research Article; Understanding the processes of air pollution formation; Urban areas; Vapors; 中国生产; 云凝结核; 平均增长率; 粒子数; 纳米颗粒; 网站; 长江三角洲
• ISSN: 2095-2201; 2095-221X
• DOI: 10.1007/s11783-016-0833-2

Long-term continuous measurements of particle number size distributions with mobility diameter sizes ranging from 3 to 800 nm were pertbrmed to study new particle formation （NPF） events at Shangdianzi （SDZ）, Mt. Tai （TS）, and Lin＇an （LAN） stations representing the background atmospheric conditions in the North China Plain （NCP） Central East China （CEC） and Yangtze River Delta （YRD） regions, respectively. The mean formation rate of 3-nm particles was 6.3, 3.7, and 5.8 cm -3 .s-1, and the mean particle growth rate was 3.6, 6.0, and 6.2 nm. h at SDZ, TS, and LAN, respectively. The NPF, event characteristics at the three sites indicate that there may be a stronger source of low volatile vapors and higher condensational sink of pre-existing particles in the YRD region. The formation rate of NPF events at these sites, as well as the condensation sink, is approximately 10 times higher than some results reported at rural/urban sites in western countries. However, the growth rates appear to be 1 2 times higher. Approximately 12%-17% of all NPF events with nucleated particles grow to a climate- relevant size （〉50 nm）. These kinds of NPF events were normally observed with higher growth rate than the other NPF cases. Generally, the cloud condensation nuclei （CCN） number concentration can be enhanced by approximately a factor of 2 6 on these event days. The mean value of the enhancement factor is lowest at LAN （2-3） and highest at SDZ （-4）. NPF events have also been found to have greater impact on CCN production in China at the regional scale than in the other background sites worldwide.