Integration & Synthesis of Current Research into the Formation, Evolution and Roles of Cloud Condensation Nuclei in the Marine Environment

一体化

• 批准号: NE/G000247/1
• 负责人: Gordon McFiggans
• 金额: $ 6.31万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FG000247%2F1
• 关键词: Integration; Synthesis; Current; Research; into

The oceans appears dark blue from space in the absence of cloud cover but appear significantly brighter when extensive sheets of stratocumulus clouds that cover large expanses of the ocean surface are present. This is a manifestation of the close coupling between the ocean surface and the radiative properties of clouds. Factors controlling the number and nature of the particles and in turn properties of the marine stratocumulus may thus play a major role in the global radiation balance. Links describing the relationships between radiation and the seeds upon which cloud droplets form are poorly quantified and provide the most uncertain forcings of climate currently assessed by the IPCC. Evaporation of seawater droplets generated by bubble bursting and spray torn from wave tops by wind form sea spray particles ranging from below 100 nm to several microns in diameter. These may act as cloud condensation nuclei (CCN) and subsequently cloud droplets. Cloud droplet number concentration (Nd) is highly dependent on number, size and composition of particles entering the cloud. Nd in turn controls the radiative properties of the cloud, the greater Nd, the more reflective the cloud. For a given cloud water content, higher Nd results in smaller average droplet size. Clouds comprising more small droplets last longer before onset of rain than those comprising fewer large droplets. Both effects change the amount of radiation reaching the surface and impact on regional and global surface temperatures. Marine CCN number will be significantly affected by the primary particle flux from the sea surface. The size and number of droplets, and hence aerosol, produced varies greatly with conditions: wind speed, wave state etc. Size and composition determine the surface tension and chemical activity of the growing drops, key parameters in determining whether an aerosol particle will form a cloud droplet. Previously, sea spray particles have been assumed to be composed of inorganic salts similar to bulk seawater, mainly sodium chloride. However, biological detritus which is significantly hydrophobic may partition to the ocean surface forming a film and recent work has shown that particles between 100 nm and 1 micron size dominating the particle number in the marine atmosphere are rich in organic material from this sea-surface microlayer. UK SOLAS has funded three projects which are investigating aspects of the formation and control of CCN in the marine atmosphere. SEASAW and ACMME are experimental programmes aiming to quantify the fluxes and properties of marine CCN respectively. The GLOMAP aerosol modelling project aims to quantify impacts of marine CCN. It is proposed to capitalise on the funded projects to increase combined outputs both by transferring knowledge between the projects and by consolidating and extending the collaboration with national, EU and broader international partners. An initial workshop will be conducted with a large number of identified collaborators to explore the optimum mechanisms for improving our understanding of the role of various processes controlling CCN production, properties and impacts. The collaborators are already actively engaged in aspects of research into marine CCN and significant synergy exists between the funded research in all cases. Expertise ranges from direct measurements of seaspray fluxes, through measurements of marine aerosol properties and detailed identification of organic components. All programmes have overlapping interests but significant unique advantages so allowing full exploration of joint scientific findings, inaccessible from individual projects. These will be explored in the initial meeting and followed up in subsequent smaller scale exchanges. One identified knowledge transfer activity to be conducted is the compilation and review of available marine CCN data, providing direct enhancement to the measurement projects and necessary evaluation data for global modelling.

在没有云层覆盖的情况下，海洋从太空中看起来是深蓝色的，但当大量的层积云覆盖了大片的海洋表面时，海洋看起来明显更亮。这是海洋表面和云的辐射特性之间密切耦合的表现。因此，控制粒子数量和性质的因素以及海洋层积云的性质可能在全球辐射平衡中发挥重要作用。描述辐射和云滴形成的种子之间关系的联系很难量化，并且提供了IPCC目前评估的最不确定的气候强迫。由于气泡破裂而产生的海水液滴和被风从浪顶撕裂的浪花蒸发，形成直径在100纳米以下至几微米的海雾颗粒。这些云可以作为云凝结核（CCN）和随后的云滴。云滴数浓度（Nd）高度依赖于进入云的粒子的数量、大小和成分。Nd反过来控制着云的辐射特性，Nd越大，云的反射性越强。对于一个给定的云水含量，较高的钕导致较小的平均液滴尺寸。包含较多小水滴的云比包含较少大水滴的云在降雨前持续的时间更长。这两种效应都改变了到达地表的辐射量，并对区域和全球地表温度产生影响。海洋CCN数受来自海面的初级粒子通量的显著影响。液滴的大小和数量，以及由此产生的气溶胶，随风速、波浪状态等条件的变化而变化很大。大小和成分决定了不断增长的液滴的表面张力和化学活性，这是决定气溶胶粒子是否会形成云滴的关键参数。以前，海雾颗粒被认为是由类似于散装海水的无机盐组成，主要是氯化钠。然而，具有显著疏水性的生物碎屑可能会分配到海洋表面，形成一层薄膜，最近的工作表明，海洋大气中占主导地位的100 nm至1微米大小的颗粒富含海洋表面微层的有机物质。联合王国《海上人命安全公约》资助了三个项目，这些项目正在调查海洋大气中云凝结核的形成和控制。SEASAW和ACMME是分别旨在量化海洋云凝结核通量和性质的实验计划。GLOMAP气溶胶建模项目旨在量化海洋云凝结核的影响。建议通过在项目之间转移知识以及巩固和扩大与国家、欧盟和更广泛的国际合作伙伴的合作，利用资助的项目增加综合产出。第一次研讨会将与大量确定的合作者一起进行，以探索最佳机制，以提高我们对控制云凝结核生产，性质和影响的各种过程的作用的理解。合作者已经积极参与海洋云凝结核研究的各个方面，在所有情况下，受资助的研究之间都存在着重大的协同作用。专业知识包括直接测量海雾通量、测量海洋气溶胶特性和详细鉴定有机成分。所有方案都有重叠的利益，但具有重要的独特优势，因此可以充分探索联合科学发现，而这是单个项目无法实现的。这些问题将在首次会议上探讨，并在随后的较小规模交流中采取后续行动。已确定的一项知识转让活动是汇编和审查现有的海洋云凝结核数据，直接加强测量项目和全球建模所需的评价数据。

项目成果

On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol - Part 1: Source fluxes

• DOI: 10.5194/acp-10-9295-2010
• 发表时间: 2010-01-01
• 期刊: ATMOSPHERIC CHEMISTRY AND PHYSICS
• 影响因子: 6.3
• 作者: Fuentes, E.;Coe, H.;McFiggans, G.
• 通讯作者: McFiggans, G.

On the impacts of phytoplankton-derived organic matter on the properties of the primary marine aerosol - Part 2: Composition, hygroscopicity and cloud condensation activity

• DOI: 10.5194/acp-11-2585-2011
• 发表时间: 2011-01-01
• 期刊: ATMOSPHERIC CHEMISTRY AND PHYSICS
• 影响因子: 6.3
• 作者: Fuentes, E.;Coe, H.;McFiggans, G.
• 通讯作者: McFiggans, G.

Aerosol mass spectrometer constraint on the global secondary organic aerosol budget

• DOI: 10.5194/acp-11-12109-2011
• 发表时间: 2011-12
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: D. Spracklen;J. Jimenez;K. Carslaw;D. Worsnop;M. J. Evans;G. Mann;Q. Zhang;M. Canagaratna

Primary Marine Aerosol Fluxes

初级海洋气溶胶通量

• DOI: 10.1175/2010bams3112.1
• 发表时间: 2011
• 期刊: Bulletin of the American Meteorological Society
• 影响因子: 8
• 作者: Brooks I

A synthesis of cloud condensation nuclei counter (CCNC) measurements within the EUCAARI network

• DOI: 10.5194/acp-15-12211-2015
• 发表时间: 2015-11
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: M. Paramonov;V. Kerminen;M. Gysel;P. Aalto;M. Andreae;E. Asmi;U. Baltensperger;A. Bougiatioti;D. Brus;G. Frank;N. Good;S. S. Gunthe-S.;L. Hao;M. Irwin;A. Jaatinen;Z. Jurányi;S. King;A. Kortelainen;A. Kristensson;H. Lihavainen;M. Kulmala;U. Lohmann;S. Martin;G. Mcfiggans;N. Mihalopoulos;A. Nenes;C. O’Dowd;J. Ovadnevaitė;T. Petäjä;U. Pöschl;G. Roberts;D. Rose;B. Svenningsson;E. Swietlicki;E. Weingartner;J. Whitehead;A. Wiedensohler;C. Wittbom;B. Sierau