Articles | Volume 25, issue 11
https://doi.org/10.5194/acp-25-5761-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-5761-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Insights into the real part of natural sea spray aerosol refractive index in the Pacific Ocean
Chengyi Fan
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
Bishuo He
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
Shuqi Guo
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
Jie Qiu
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
Chunsheng Zhao
CORRESPONDING AUTHOR
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China
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Gang Zhao, Yishu Zhu, Zhijun Wu, Taomou Zong, Jingchuan Chen, Tianyi Tan, Haichao Wang, Xin Fang, Keding Lu, Chunsheng Zhao, and Min Hu
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New particle formation is thought to contribute half of the global cloud condensation nuclei. We find that the new particle formation is more likely to happen in the upper boundary layer than that at the ground, which can be partially explained by the aerosol–radiation interaction. Our study emphasizes the influence of aerosol–radiation interaction on the NPF.
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Aerosol hygroscopicity measured by the humidified tandem differential mobility analyzer (HTDMA) is affected by multiply charged particles from two aspects: (1) number contribution and (2) the weakening effect. An algorithm is proposed to do the multi-charge correction and applied to a field measurement. Results show that the difference between corrected and measured size-resolved κ can reach 0.05, highlighting that special attention needs to be paid to the multi-charge effect when using HTDMA.
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Submicron particles larger than 300 nm dominate the aerosol light extinction and mass concentration in the urban environment. Aerosol hygroscopic properties extended to 600 nm were investigated at an urban site. Our results find that there exists a large fraction of a less hygroscopic group above 300 nm, and the hygroscopicity in this size range is enhanced significantly with the development of pollution levels. The hygroscopicity variation contributes greatly to the low visibility.
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Short summary
Marine aerosols play a critical role in weather and climate, and their real part of the refractive index (RRI) is a key factor in their radiative effects. We present a study of RRI measurements using optical tweezer technology and find that the calculated results of RRI using the traditional method disagree with the measurements. A parameterization of the RRI and relative humidity relationship is proposed, and it will improve the radiation calculation in numerical models.
Marine aerosols play a critical role in weather and climate, and their real part of the...
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