Significant effects of transport on nanoparticles during new particle formation events in the atmosphere of Beijing

The mechanisms of new particle formation (NPF) events that occurred under high aerosol loadings (polluted NPF) in the atmosphere have been unclear, which has inhibited the precision of particle pollution control. To deepen the understanding of how the polluted NPF events occur, a one-month comprehensive measurement was conducted in the atmosphere of Beijing during the summer of 2016. The clean NPF events (frequency = 22%) (condensation sink, CS < 0.015 s-1) were found to be caused by local nucleation and growth. The polluted NPF events (frequency = 28%) (CS > 0.015 s-1) were influenced by both local nucleation-growth and regional transport, and the contributions from the two factors to 6-25 nm particle number concentration were 60% and 40%, respectively. This study emphasized the importance of the transport for nanoparticles in relatively polluted atmospheres, and for that the regional joint particle pollution control would be an essential policy. (c) 2023 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

A one-month comprehensive measurement was conducted in Beijing during the summer of 2016 to deepen the understanding of how polluted new particle formation (NPF) events occur. The study found that clean NPF events were caused by local nucleation and growth, while polluted NPF events were influenced by both local nucleation-growth and regional transport. The contributions of these factors to particle number concentration were 60% and 40% respectively.