气候变化领域集成服务门户(CCPortal): Active sites for ice nucleation differ depending on nucleation mode

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DOI	10.1073/pnas.2022859118
	Active sites for ice nucleation differ depending on nucleation mode
	Holden M.A.; Campbell J.M.; Meldrum F.C.; Murray B.J.; Christenson H.K.
发表日期	2021
ISSN	0027-8424
卷号	118 期号:18
英文摘要	The nucleation of ice crystals in clouds is poorly understood, despite being of critical importance for our planet's climate. Nucleation occurs largely at rare “active sites” present on airborne particles such as mineral dust, but the nucleation pathway is distinct under different meteorological conditions. These give rise to two key nucleation pathways where a particle is either immersed in a supercooled liquid water droplet (immersion freezing mode) or suspended in a supersaturated vapor (deposition mode). However, it is unclear if the same active sites are responsible for nucleation in these two modes. Here, we directly compare the sites that are active in these two modes by performing immersion freezing and deposition experiments on the same thin sections of two atmospherically important minerals (feldspar and quartz). For both substrates, we confirm that nucleation is dominated by a limited number of sites and show that there is little correlation between the two sets of sites operating in each experimental method: across both materials, only six out of 73 sites active for immersion freezing nucleation were also active for deposition nucleation. Clearly, different properties determine the activity of nucleation sites for each mode, and we use the pore condensation and freezing concept to argue that effective deposition sites have size and/or geometry requirements not of relevance to effective immersion freezing sites. Hence, the ability to nucleate is pathway dependent, and the mode of nucleation has to be explicitly considered when applying experimental data in cloud models. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Active sites; Crystallization; Ice; Nucleation; Pores
语种	英语
scopus关键词	Article; cooling; crystal; freezing; ice nucleation; immersion; low temperature procedures; priority journal; surface property; suspension
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/238744
作者单位	School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom; School of Physical Sciences and Computing, University of Central Lancashire, Preston, PR1 2HE, United Kingdom; School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom; School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, United Kingdom
推荐引用方式 GB/T 7714	Holden M.A.,Campbell J.M.,Meldrum F.C.,et al. Active sites for ice nucleation differ depending on nucleation mode[J],2021,118(18).
APA	Holden M.A.,Campbell J.M.,Meldrum F.C.,Murray B.J.,&Christenson H.K..(2021).Active sites for ice nucleation differ depending on nucleation mode.Proceedings of the National Academy of Sciences of the United States of America,118(18).
MLA	Holden M.A.,et al."Active sites for ice nucleation differ depending on nucleation mode".Proceedings of the National Academy of Sciences of the United States of America 118.18(2021).