Abstract
This study employed multiple techniques to investigate the contribution of grown new particles to the number concentration of cloud condensation nuclei (CCN) at various supersaturation (SS) levels at a rural mountain site in the North China Plain from 29 June to 14 July 2019. On 8 new particle formation (NPF) days, the total particle number concentrations (Ncn) were 8.4 ± 6.1 × 103 cm−3, which was substantially higher compared to 4.7 ± 2.6 × 103 cm−3 on non-NPF days. However, the CCN concentration (Nccn) at 0.2 % SS and 0.4 % SS on the NPF days was significantly lower than those observed on non-NPF days (p < 0.05). This was due to the lower cloud activation efficiency of preexisting particles resulting from organic vapor condensation and smaller number concentrations of preexisting particles on NPF days. A case-by-case examination showed that the grown new particles only yielded a detectable contribution to Nccn at 0.4 % SS and 1.0 % SS during the NPF event on 1 July 2019, accounting for 12 % ± 11 % and 23 % ± 12 % of Nccn, respectively. The increased Nccn during two other NPF events and at 0.2 % SS on 1 July 2019 were detectable but determined mainly by varying preexisting particles rather than grown new particles. In addition, the hygroscopicity parameter values, concentrations of inorganic and organic particulate components, and surface chemical composition of different sized particles were analyzed in terms of chemical drivers to grow new particles. The results showed that the grown new particles via organic vapor condensation generally had no detectable contribution to Nccn but incidentally did. However, this conclusion was drawn from a small size of observational data, leaving more observations, particularly long-term observations and the growth of preexisting particles to the CCN required size, needed for further investigation.
| Original language | English |
|---|---|
| Pages (from-to) | 15325-15350 |
| Number of pages | 26 |
| Journal | Atmospheric Chemistry and Physics |
| Volume | 23 |
| Issue number | 24 |
| DOIs | |
| State | Published - Dec 15 2023 |
Funding
This research was supported by the National Natural Science Foundation of China (grant no. 42276036) and the Hainan Provincial Natural Science Foundation of China (grant no. 422MS098). This paper has been authored by UT-Battelle, LLC, under contract no. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this paper, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan , last access: 1 September 2023). This research was funded by the National Natural Science Foundation of China (grant no. 42276036) and Hainan Provincial Natural Science Foundation of China (grant no. 422MS098). The paper preparation for XYY was supported partially by the strategic Laboratory Directed Research and Development (LDRD) of the Physical Sciences Directorate of the Oak Ridge National Laboratory (ORNL).