气候变化领域集成服务门户(CCPortal): Activation of atmospheric aerosols in fog and low clouds

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DOI	10.1016/j.atmosenv.2020.117490
	Activation of atmospheric aerosols in fog and low clouds
	Zíková N.; Pokorná P.; Makeš O.; Sedlák P.; Pešice P.; Ždímal V.
发表日期	2020
ISSN	1352-2310
卷号	230
英文摘要	Ground-based measurements of low stratus or fog at a mountain station in the Czech Republic have been conducted to describe the cloud nucleus activation process from the perspectives of size dependence, effectiveness, and speed. The activated particles were estimated from the difference in measured aerosol concentration between the whole-air inlet (WAI) and PM2.5 interstitial inlet. Both inlets were connected via a switching valve to a scanning mobility particle sizer (SMPS) and aerodynamic particle sizer (APS), thereby measuring aerosol particles from 15 nm to 20 μm in size. Episodes of fog, freezing fog, and mist were studied; however, during the mist episodes, no activation occurred. Most of the differences between fog and freezing fog were comparable to the measurement uncertainty. The activated fraction reached over 90 % for particles larger than 450 and 510 nm for fog and freezing fog, respectively. The smallest activated diameter, 130 nm, was identical for fog and freezing fog. The activation process speed, derived from the time evolution of the size-dependent activated fraction function (AFF), was also similar for fog and freezing fog. The AFF becomes steeper, and the inflection point moves to smaller particles. For most episodes, 120 min after initiation, the AFF reached a steady state. The effectiveness, speed, and size dependence of the activation process were found to be connected with the air mass history, a proxy for the air mass composition and liquid water content, resp. supersaturation. For continental air masses, the activated fraction was independent of the air mass history, and the activated particle mode position only ranged from 230 to 260 nm. For maritime air masses, smaller particles were activated with the mode shifted to 120 nm. © 2020 Elsevier Ltd
英文关键词	Activated fraction; Atmospheric aerosol; Fog formation; Liquid water content; Positive matrix factorization; Stratus
语种	英语
来源期刊	Atmospheric Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129519
作者单位	Department of Aerosol Chemistry and Physics, Institute of Chemical Process Fundamentals, Czech Academy of Sciences, Rozvojová 2/135, Prague, 165 02, Czech Republic; Institute for Environmental Studies, Faculty of Science, Charles University in Prague, Albertov 6, Prague, 128 43, Czech Republic; Department of Meteorology, Institute of Atmospheric Physics, Czech Academy of Sciences, Boční II, Prague, 141 00, Czech Republic
推荐引用方式 GB/T 7714	Zíková N.,Pokorná P.,Makeš O.,et al. Activation of atmospheric aerosols in fog and low clouds[J],2020,230.
APA	Zíková N.,Pokorná P.,Makeš O.,Sedlák P.,Pešice P.,&Ždímal V..(2020).Activation of atmospheric aerosols in fog and low clouds.Atmospheric Environment,230.
MLA	Zíková N.,et al."Activation of atmospheric aerosols in fog and low clouds".Atmospheric Environment 230(2020).