气候变化领域集成服务门户(CCPortal): The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere

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DOI	10.5194/acp-20-15037-2020
	The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere
	Kupc A.; Williamson C.J.; Hodshire A.L.; Kazil J.; Ray E.; Paul Bui T.; Dollner M.; Froyd K.D.; McKain K.; Rollins A.; Schill G.P.; Thames A.; Weinzierl B.B.; Pierce J.R.; Brock C.A.
发表日期	2020
ISSN	1680-7316
起始页码	15037
结束页码	15060
卷号	20 期号:23
英文摘要	Global observations and model studies indicate that new particle formation (NPF) in the upper troposphere (UT) and subsequent particles supply 40 %?60% of cloud condensation nuclei (CCN) in the lower troposphere, thus affecting the Earth?s radiative budget. There are several plausible nucleation mechanisms and precursor species in this atmospheric region, which, in the absence of observational constraints, lead to uncertainties in modeled aerosols. In particular, the type of nucleation mechanism and concentrations of nucleation precursors, in part, determine the spatial distribution of new particles and resulting spatial distribution of CCN from this source. Although substantial advances in understanding NPF have been made in recent years, NPF processes in the UT in pristine marine regions are still poorly understood and are inadequately represented in global models. Here, we evaluate commonly used and state-of-The-Art NPF schemes in a Lagrangian box model to assess which schemes and precursor concentrations best reproduce detailed in situ observations. Using measurements of aerosol size distributions (0.003Dp 4.8 um) in the remote marine troposphere between 0:18 and 13 km altitude obtained during the NASA Atmospheric Tomography (ATom) mission, we show that high concentrations of newly formed particles in the tropical UT over both the Atlantic and Pacific oceans are associated with outflow regions of deep convective clouds. We focus analysis on observations over the remote Pacific Ocean, which is a region less perturbed by continental emissions than the Atlantic. Comparing aerosol size distribution measurements over the remote Pacific with box model simulations for 32 cases shows that none of the NPF schemes most commonly used in global models, including binary nucleation of sulfuric acid and water (neutral and ionassisted) and ternary involving sulfuric acid, water, and ammonia, are consistent with observations, regardless of precursor concentrations. Through sensitivity studies, we find that the nucleation scheme among those tested that is able to explain most consistently (21 of 32 cases) the observed size distributions is that of Riccobono et al. (2014), which involves both organic species and sulfuric acid. The method of Dunne et al. (2016), involving charged sulfuric acid?water? ammonia nucleation, when coupled with organic growth of the nucleated particles, was most consistent with the observations for 5 of 32 cases. Similarly, the neutral sulfuric acid? water?ammonia method of Napari (2002), when scaled with a tuning factor and with organic growth added, was most consistent for 6 of 32 cases. We find that to best reproduce both nucleation and growth rates, the mixing ratios of gas-phase organic precursors generally need to be at least twice that of SO2, a proxy for dimethyl sulfide (DMS). Unfortunately we have no information on the nature of oxidized organic species that participated in NPF in this region. Global models rarely include organic-driven nucleation and growth pathways in UT conditions where globally significant NPF takes place, which may result in poor estimates of NPF and CCN abundance and contribute to uncertainties in aerosol?cloud? radiation effects. Furthermore, our results indicate that the organic aerosol precursor vapors may be important in the tropical UT above marine regions, a finding that should guide future observational efforts. © 2020 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	aerosol; cloud condensation nucleus; concentration (composition); convective cloud; Lagrangian analysis; marine atmosphere; particulate matter; spatial distribution; tropical meteorology; troposphere; Atlantic Ocean; Pacific Ocean
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/247304
作者单位	Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, United States; Faculty of Physics, Aerosol Physics and Environmental Physics, University of Vienna, Vienna, 1090, Austria; Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, United States; Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523, United States; Earth Science Division, Nasa Ames Research Center, Moffett Field, CA, United States; Global Monitoring Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, United States; Department of Meteorology and Atmospheric Science, Pennsylvania State University, University Park, PA, United States
推荐引用方式 GB/T 7714	Kupc A.,Williamson C.J.,Hodshire A.L.,et al. The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere[J],2020,20(23).
APA	Kupc A..,Williamson C.J..,Hodshire A.L..,Kazil J..,Ray E..,...&Brock C.A..(2020).The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(23).
MLA	Kupc A.,et al."The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.23(2020).