Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/acp-2018-121
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
06 Apr 2018
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).
Intermittent turbulence contributes to vertical diffusion of PM2.5 in the North China Plain
Wei Wei1, Hongsheng Zhang2, Bingui Wu3, Yongxiang Huang4, Xuhui Cai5, Yu Song5, and Jianduo Li1 1State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China
2Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100081, China
3Tianjin Municipal Meteorological Bureau, Tianjin 300074, China
4State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China
5State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environmental Science, Peking University, Beijing 100081, China
Abstract. Heavy particulate pollution events have frequently occurred in the North China Plain over the past decades. Due to high emissions and poor diffusion conditions, issues become increasingly serious during cold seasons. Although early studies have explored some potential reasons for air pollutions, there are few works focusing on the effects of intermittent turbulence. This paper draws upon two typical PM2.5 (particulate matters with diameter less than 2.5 mm) pollution cases from the winter of 2016–2017. After several days of gradual accumulation, the concentration of PM2.5 near the surface reached the maximum as a combined result of strong inversion layer, stagnant wind and high ambient humidity and then sharply decreased to a very low level within a few hours. In order to identify the strength of turbulent intermittency, an effective index, called Intermittency Factor (IF), was proposed by this work. The results show that the turbulence during the stage of diffusion is highly intermittent and not locally generated. The vertical characteristics of IF and wind filed confirm the generation and downward transport of intermittent turbulence from the wind shear associated with low-level jets. The intermittently turbulent fluxes contribute positively to the vertical dispersion of particulate matters and improve the air quality near the surface. This work brought up a possible mechanism of how intermittent turbulence affects the diffusion of particulate matters.
Citation: Wei, W., Zhang, H., Wu, B., Huang, Y., Cai, X., Song, Y., and Li, J.: Intermittent turbulence contributes to vertical diffusion of PM2.5 in the North China Plain, Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-121, in review, 2018.
Wei Wei et al.
Wei Wei et al.
Wei Wei et al.

Viewed

Total article views: 244 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
173 65 6 244 4 7

Views and downloads (calculated since 06 Apr 2018)

Cumulative views and downloads (calculated since 06 Apr 2018)

Viewed (geographical distribution)

Total article views: 244 (including HTML, PDF, and XML)

Thereof 242 with geography defined and 2 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 20 Apr 2018
Publications Copernicus
Download
Short summary
Heavy particulate pollution events have frequently occurred in the North China Plain. Using the Intermittency Factor, we found that the turbulence during the transport stage is intermittent and not locally generated. Turbulence results from the wind shear of low-level jets and then transports downward, causing intermittent turbulence at lower levels. The intermittent turbulence contributes positively to the vertical dispersion of particulate matters and improves the air quality near the surface.
Heavy particulate pollution events have frequently occurred in the North China Plain. Using the...
Share