气候变化领域集成服务门户(CCPortal): Regional new particle formation as modulators of cloud condensation nuclei and cloud droplet number in the eastern Mediterranean

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DOI	10.5194/acp-19-6185-2019
	Regional new particle formation as modulators of cloud condensation nuclei and cloud droplet number in the eastern Mediterranean
	Kalkavouras P.; Bougiatioti A.; Kalivitis N.; Stavroulas I.; Tombrou M.; Nenes A.; Mihalopoulos N.
发表日期	2019
ISSN	16807316
起始页码	6185
结束页码	6203
卷号	19 期号:9
英文摘要	A significant fraction of atmospheric particles that serve as cloud condensation nuclei (CCN) are thought to originate from the condensational growth of new particle formation (NPF) from the gas phase. Here, 7 years of continuous aerosol and meteorological measurements (June 2008 to May 2015) at a remote background site of the eastern Mediterranean were recorded and analyzed to assess the impact of NPF (of 162 episodes identified) on CCN and cloud droplet number concentration (CDNC) formation in the region. A new metric is introduced to quantitatively determine the initiation and duration of the influence of NPF on the CCN spectrum. NPF days were found to increase CCN concentrations (from 0.10% to 1.00% supersaturation) between 29%and 77 %. Enhanced CCN concentrations from NPF are mostly observed, as expected, under low preexisting particle concentrations and occur in the afternoon, relatively later in the winter and autumn than in the summer. Potential impacts of NPF on cloud formation were quantified by introducing the observed aerosol size distributions and chemical composition into an established cloud droplet parameterization. We find that the supersaturations that develop are very low (ranging between 0.03% and 0.27 %) for typical boundary layer dynamics (σw ∼ 0:3m s-1) and NPF is found to enhance CDNC by a modest 13 %. This considerable contrast between CCN and CDNC response is in part from the different supersaturation levels considered, but also because supersaturation drops from increasing CCN because of water vapor competition effects during the process of droplet formation. The low cloud supersaturation further delays the appearance of NPF impacts on CDNC to clouds formed in the late evening and nighttime - which has important implications for the extent and types of indirect effects induced by NPF events. An analysis based on CCN concentrations using prescribed supersaturation can provide very different, even misleading, conclusions and should therefore be avoided. The proposed approach here offers a simple, yet highly effective way for a more realistic impact assessment of NPF events on cloud formation. © Author(s) 2019.
语种	英语
scopus关键词	aerosol; chemical composition; cloud condensation nucleus; cloud droplet; concentration (composition); size distribution; supersaturation; water vapor; Mediterranean Region
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/144426
作者单位	Enviromental Chemical Processes Laboratory, Department of Chemistry, University of Crete, Heraklion, 71003, Greece; Institute of Environmental Research and Sustainable Development, National Observatory of Athens, Palea Penteli, 15236, Greece; Energy Environment and Water Research Center, Cyprus Institute, Nicosia, 2121, Cyprus; Department of Physics, University of Athens, Athens, 15784, Greece; Laboratory of Atmospheric Processes and Their Impacts, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, 1015, Switzerland; Institute for Chemical Engineering Science, Foundation for Research and Technology Hellas, Patras, 26504, Greece
推荐引用方式 GB/T 7714	Kalkavouras P.,Bougiatioti A.,Kalivitis N.,et al. Regional new particle formation as modulators of cloud condensation nuclei and cloud droplet number in the eastern Mediterranean[J],2019,19(9).
APA	Kalkavouras P..,Bougiatioti A..,Kalivitis N..,Stavroulas I..,Tombrou M..,...&Mihalopoulos N..(2019).Regional new particle formation as modulators of cloud condensation nuclei and cloud droplet number in the eastern Mediterranean.Atmospheric Chemistry and Physics,19(9).
MLA	Kalkavouras P.,et al."Regional new particle formation as modulators of cloud condensation nuclei and cloud droplet number in the eastern Mediterranean".Atmospheric Chemistry and Physics 19.9(2019).