Efficient Nitrate Formation in Fog Events Implicates Fog Interstitial Aerosols as Significant Drivers of Atmospheric Chemistry
Clouds and fogs, consisting of tiny water droplets formed by the condensation of water in supersaturated air, are vital in atmospheric chemistry, as they facilitate multiphase reactions. While measuring high-altitude cloud is challenging, fog as ground-level clouds offer a unique opportunity for direct observation. In this study, we explored radiation fogs in the North China Plain using an advanced aerosol-fog sampling system to measure the chemical and physical properties of both inactivated interstitial aerosols and activated fog droplet residues. Our findings revealed that efficient nitrate formation primarily occurred on fog interstitial aerosols rather than within fog droplets, with observed fog interstitial aerosol nitrate net production rates reaching up to 3.6 μg m<sup>-3</sup> h<sup>-1</sup>. Box model simulations identified the hydrolysis of NO<sub>2</sub> and N<sub>2</sub>O<sub>5</sub> as key pathways for nitrate formation. NO<sub>2</sub> hydrolysis was often overlooked in previous studies, contributing 40-79 and 57-76% to total nitrate production during nighttime and daytime fog periods. This oversight suggests that substantial nitrate formation through hydrolysis reactions involving interstitial aerosols may have been neglected. Our results highlight the need for further research into the chemistry of cloud and fog interstitial aerosols and their inclusion in atmospheric chemistry models.
Authors
- Wanyun Xu (ORCID: https://orcid.org/0000-0003-4787-1754)
- Hongbing Cheng (ORCID: https://orcid.org/0000-0002-8504-1092)
- Weiqi Xu
- Xiaobin Xu (ORCID: https://orcid.org/0000-0003-4321-9267)
- Yele Sun (ORCID: https://orcid.org/0000-0003-2354-0221)
- Pengfei Liu (ORCID: https://orcid.org/0000-0001-7280-9720)
- Linlin Liang (ORCID: https://orcid.org/0000-0003-1323-2460)
- Sanxue Ren
- Chang Liu (ORCID: https://orcid.org/0000-0002-0662-037X)
- Ye Kuang (ORCID: https://orcid.org/0000-0002-0782-8877)
- Xiaoyi Zhang (ORCID: https://orcid.org/0009-0002-3470-7568)
- Li Liu (ORCID: https://orcid.org/0000-0001-9603-1386)
- Gen Zhang (ORCID: https://orcid.org/0000-0001-9622-4620)
- Hanbing Xu
- Xinfeng Wang (ORCID: https://orcid.org/0000-0003-0911-7312)
- Junwen Liu (ORCID: https://orcid.org/0000-0002-7252-3017)
- Yusi Liu (ORCID: https://orcid.org/0000-0001-7571-8162)
- Jiangchuan Tao (ORCID: https://orcid.org/0009-0007-7118-8070)
- Miaomiao Zhai (ORCID: https://orcid.org/0000-0001-9745-8410)
- Guangsheng Zhou (ORCID: https://orcid.org/0000-0001-6303-1275)
- Huarong Zhao (ORCID: https://orcid.org/0000-0002-4265-7065)
- Biao Luo
Institutions
- Georgia Institute of Technology (US)
- China Meteorological Administration (CN)
- Shandong University (CN)
- Sun Yat-sen University (CN)
- Jinan University (CN)
- Chinese Academy of Sciences (CN)
- Fudan University (CN)
- Chinese Academy of Meteorological Sciences (CN)
- Institute of Atmospheric Physics (CN)
Publication Details
- Journal
- Environmental Science & Technology
- Published
- 2024-11-22
- DOI
- https://doi.org/10.1021/acs.est.4c09078
- Citations
- 7
- Primary Topic
- Atmospheric chemistry and aerosols
- Type
- article
- Field-Weighted Citation Impact
- 2.63
Funders
- National Natural Science Foundation of China