气候变化领域集成服务门户(CCPortal): A new CCN activation parameterization and its potential influences on aerosol indirect effects

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DOI	10.1016/j.atmosres.2021.105491
	A new CCN activation parameterization and its potential influences on aerosol indirect effects
	Wang Y.; Niu S.; Lu C.; Fan S.; Lv J.; Xu X.; Jin Y.; Sun W.
发表日期	2021
ISSN	0169-8095
卷号	253
英文摘要	Unactivated particles mixed in cloud condensation nuclei (CCN) measurements lead to inaccurate activation parameterization, thereby overestimating aerosol indirect effects in current models. Data from five CCN field campaigns in Eastern China are analyzed to identify unactivated particles. The lower temperature, lower aerosol hygroscopicity (κ), and the aerosol particle size distribution closer to that in the coast (compared to that in the continent) lead to a higher proportion of unactivated particles in CCN measurements; the underlying physical mechanisms are discussed. A correction for the CCN activation parameterization is essential for regions with the above characteristics. After removing the unactivated particles, it is found that the widely used Twomey power-law activation parameterization does not adequately fit the relationship between the corrected CCN concentration and the supersaturation; therefore, a new, better-fitting, two-parameter activation parameterization is proposed. A method is presented for estimating the parameters in the new parameterization according to the κ-Köhler theory, that is, the two parameters can be estimated as 59% and 66% of aerosol number concentration for continental regions (represented by Nanjing, 32.21°N, 118.70°E) and 69% and 79% of that for coastal regions (represented by Shenzhen, 22.48°N, 114.56°E), respectively. The new CCN activation parameterization significantly reduces the overestimation of CCN concentration at low supersaturation (SS) conditions, e.g., at SS = 0.1% in the five CCN campaigns, the overestimation is 77% to 102% for the classical power-law parameterization and only 6% to 13% for the new parameterization. As a result, the new parameterization may reduce the overestimation of aerosol indirect effects in models, especially at low supersaturation conditions. © 2021
英文关键词	Aerosol indirect effects; CCN activation parameterization; Cloud condensation nuclei (CCN); Unactivated particles
来源期刊	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/236844
作者单位	Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science & Technology, Nanjing, China; College of Safety Science and Engineering, Nanjing Tech University, Nanjing, China
推荐引用方式 GB/T 7714	Wang Y.,Niu S.,Lu C.,et al. A new CCN activation parameterization and its potential influences on aerosol indirect effects[J],2021,253.
APA	Wang Y..,Niu S..,Lu C..,Fan S..,Lv J..,...&Sun W..(2021).A new CCN activation parameterization and its potential influences on aerosol indirect effects.Atmospheric Research,253.
MLA	Wang Y.,et al."A new CCN activation parameterization and its potential influences on aerosol indirect effects".Atmospheric Research 253(2021).