Aerosol light absorption alleviates particulate pollution during wintertime haze events
Aerosol light absorption has been widely considered as a contributing factor to the worsening of particulate pollution in large urban areas, primarily through its role in stabilizing the planetary boundary layer (PBL). Here, we report that absorption-dominated aerosol-radiation interaction can decrease near-surface fine particulate matter concentrations ([PM<sub>2.5</sub>]) at a large-scale during wintertime haze events. A "warm bubble" effect by the significant heating rate of absorbing aerosols above the PBL top generates a secondary circulation, enhancing the upward motion (downward motion) and the convergence (divergence) in polluted (relatively clean) areas, with a net effect of lowering near-surface [PM<sub>2.5</sub>]. Furthermore, aerosol absorption of ultraviolet-wave light effectively reduces the photolysis of chemical species, i.e., aerosol-photolysis interaction, hindering ozone formation, reducing atmospheric oxidizing capability, and suppressing secondary aerosol concentrations. Our model assessment reveals that the synergetic two effects decrease near-surface [PM<sub>2.5</sub>] by around 7.4%, so the presence of light-absorbing aerosols can considerably alleviate particulate pollution during wintertime haze events. Such negative feedbacks to the aerosol loading should be considered in weather/climate prediction and health assessment models.
Authors
- Junji Cao (ORCID: https://orcid.org/0000-0003-1000-7241)
- John H. Seinfeld (ORCID: https://orcid.org/0000-0003-1344-4068)
- Bo Hu (ORCID: https://orcid.org/0000-0001-6164-9784)
- Yangfan Liu (ORCID: https://orcid.org/0000-0003-0812-8853)
- Naifang Bei
- Qiyuan Wang (ORCID: https://orcid.org/0000-0003-2529-6226)
- Jiarui Wu (ORCID: https://orcid.org/0009-0009-9257-8646)
- Xiaoli Su (ORCID: https://orcid.org/0000-0003-0817-1122)
- Yuan Wang (ORCID: https://orcid.org/0000-0001-6657-8401)
- Chenchong Zhang (ORCID: https://orcid.org/0000-0003-4711-3646)
- Zirui Liu (ORCID: https://orcid.org/0000-0002-1939-9715)
- Guohui Li (ORCID: https://orcid.org/0000-0003-0033-3895)
- Ningning Zhang (ORCID: https://orcid.org/0000-0002-5103-7247)
- Xia Li (ORCID: https://orcid.org/0000-0003-1328-9061)
- Jiang Qian (ORCID: https://orcid.org/0000-0001-7238-9746)
- Ruonan Wang (ORCID: https://orcid.org/0009-0001-1567-6666)
- Yuxuan Lu
- Lili Wang (ORCID: https://orcid.org/0000-0002-0082-8487)
- Xuexi Tie
Institutions
- California Institute of Technology (US)
- Chinese Academy of Sciences (CN)
- Institute of Atmospheric Physics (CN)
- Institute of Earth Environment (CN)
- Xi'an Jiaotong University (CN)
- Stanford University (US)
Publication Details
- Journal
- Proceedings of the National Academy of Sciences
- Published
- 2024-12-23
- DOI
- https://doi.org/10.1073/pnas.2402281121
- Citations
- 4
- Primary Topic
- Atmospheric chemistry and aerosols
- Type
- article
- Field-Weighted Citation Impact
- 1.51
Funders
- National Natural Science Foundation of China
- Chinese Academy of Sciences
- National Key Research and Development Program of China