We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Nucleation and growth of sub-3 nm particles in the polluted urban atmosphere of a megacity in China.
- Authors
Yu, H.; Zhou, L. Y.; Dai, L.; Shen, W. C.; Zheng, J.; Ma, Y.; Chen, M. D.
- Abstract
Particle size distribution down to 1.38nm was measured in the urban atmosphere of Nanjing, China in spring, summer and winter during 2014-2015. Nucleation event occurred on 42 out of total 90 observation days, but new particles could grow to cloud condensation nuclei (CCN)-active sizes on only 9 days. In summer, infrequent nucleation was limited by both unfavorable meteorological conditions (high temperature and RH) and reduced anthropogenic precursor availability due to strict emission control measures during the 2014 Youth Olympic Games in Nanjing. The limiting factors for nucleation in winter and spring were meteorological conditions (radiation, temperature, and RH) and condensation sink, but for the further growth of sub-3nm particles to CCN-active sizes, anthropogenic precursors again became limiting factors. Nucleation events were strong in the polluted urban atmosphere. Initial J1.38 at the onset and peak J1.38 at the noontime could be up to 2.1 x 10² and 2.5 x 10³cm-3s-1, respectively, during the 8 nucleation events selected from different seasons. Time-dependent J1.38 usually showed good linear correlations with a sulfuric acid proxy for every single event (R² = 0.56-0.86, excluding a day with significant nocturnal nucleation), but the correlation among all the 8 events deteriorated (R² = 0.17) due to temperature or season change. We observed that new particle growth rate did not increase monotonically with particle size, but had a local maximum up to 25nmh-1 between 1-3 nm. The growth rate behavior was interpreted in this study as the solvation effect of organic activating vapor in newly formed inorganic nuclei using nano-Köhler theory.
- Subjects
NANJING (Jiangsu Sheng, China); DISCONTINUOUS precipitation; URBAN climatology; MEGALOPOLIS; PARTICLE size distribution
- Publication
Atmospheric Chemistry & Physics Discussions, 2015, Vol 15, Issue 13, p18653
- ISSN
1680-7367
- Publication type
Article
- DOI
10.5194/acpd-15-18653-2015