What the study found
The study found that iron dissolution, the process by which iron becomes dissolved in air particles, differs between the upper mixing layer and ground-level air in a megacity. In the upper mixing layer, sulfuric acid was the main driver, while near the ground nitric acid was more important.
Why the authors say this matters
The authors conclude that these findings matter because they provide new data for testing atmospheric models that simulate dissolved iron concentration and deposition. The study suggests this may help improve the accuracy of iron solubility predictions.
What the researchers tested
The researchers compared iron acid dissolution between the upper mixing layer and ground-level air, focusing on the effects of sulfuric acid and nitric acid. They also examined how particle size affected iron solubility in submicron aerosols, which are particles smaller than 1 micrometer, and supermicron particles, which are larger than 1 micrometer.
What worked and what didn't
Air masses with higher sulfate-to-nitrate ratios were associated with greater iron solubility in the upper mixing layer after atmospheric aging. The abstract reports that sulfuric acid dominated iron acidification in the upper layer and in submicron particles, while nitric acid was more important near the ground; in supermicron particles, alkaline mineral dust neutralized nitric acid and reduced iron dissolution.
What to keep in mind
The abstract presents results from a megacity and distinguishes between upper mixing layer air and ground-level air near source regions of acidic gases, so the findings are scope-specific. No additional limitations are described in the available summary.
Key points
- Iron dissolution differed between the upper mixing layer and ground-level air in a megacity.
- Sulfuric acid was the main driver in the upper mixing layer and in submicron aerosols.
- Nitric acid was more important for iron dissolution near the ground.
- Higher sulfate-to-nitrate ratios were linked to greater iron solubility after atmospheric aging.
- Mineral dust in larger particles neutralized nitric acid and suppressed iron dissolution.
Disclosure
- Research title:
- Sulfuric and nitric acids drive iron dissolution differently by air layer
- Authors:
- Guochen Wang, Bing Qi, Bingye Xu, Can Wu, Minkang Zhi, Keliang Li, Liang Xu, Qi Yuan, Yuntao Wang, Yele Sun, Zongbo Shi, Akinori Ito, Shixian Zhai, Weijun Li
- Institutions:
- China Jiliang University, China Meteorological Administration, Chinese Academy of Sciences, Chinese Academy of Social Sciences, Chinese University of Hong Kong, Communication University of Zhejiang, East China Normal University, Institute of Atmospheric Physics, Institute of Atmospheric Physics, Japan Agency for Marine-Earth Science and Technology, Ministry of Natural Resources, Ocean University of China, Second Institute of Oceanography, University of Birmingham, University of Chinese Academy of Sciences, Zhejiang Environmental Monitoring Center, Zhejiang Meteorological Bureau, Zhejiang University, Zhejiang University, Zhejiang University, Zhejiang University
- Publication date:
- 2026-01-29
- OpenAlex record:
- View
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