Aerosol-Cloud Interactions - A Directed Programme to Reduce Uncertainty in Forcing through a Targeted Laboratory and Modelling Programme

气溶胶-云相互作用 - 通过有针对性的实验室和建模程序减少强迫不确定性的定向程序

• 批准号: NE/I020121/1
• 负责人: Gordon McFiggans
• 金额: $ 110.1万
• 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: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FI020121%2F1
• 关键词: Aerosol; Cloud; Interactions; Directed; Programme

Aerosol particles act as sites for cloud droplet and ice particle formation. Cloud properties can be perturbed through the addition of aerosol particles into the atmosphere from anthropogenic and natural processes. This addition influences cloud microphysical properties, and subsequently affects cloud dynamics and thermodynamics, and the way the cloud interacts with radiation. The Earth's radiation budget is very greatly affected by clouds, and human-induced changes to the particle loading affecting them, known as indirect effects, are large and highly uncertain. A large part of this uncertainty is the result of poor knowledge of the fundamental aerosol and cloud properties and processes, leading to their poor representation in models. A programme of research is proposed here to i) directly investigate these processes in the laboratory, ii) evaluate the sensitivity of climate relevant parameters to the studied processes, iii) interpret the laboratory studies with detailed model investigations and iv) to incorporate and test new descriptions of the studied processes in cloud-scale and, where possible, global scale models. The programme will thereby reduce the uncertainty in estimates of radiative forcing and climate feedbacks relating to aerosol and cloud processes. The studies are split into those affecting warm clouds (those containing only liquid droplets) and those affecting clouds containing ice particles. The programme brings together an interdisciplinary team of researchers with expertise in 'warm' and 'cold' cloud and aerosol processes combining laboratory and multiscale modelling activities to deliver the improved predictive capability. The 'warm' laboratory work focuses on two major aspects i) the rate at which water is taken up by growing aerosol particles as they become cloud droplets (or 'activate) and ii) the ability of aerosol particles of various compositions to act as seeds for cloud droplets. These studies use a number of techniques including single particle optical levitation and investigations in a large photochemical chamber coupled to a large number of chemical and physical probes of ensembles of particles formed in simulated atmospheric chemical processes. The 'cold' work uses a similar coupling of a large, well-instrumented cloud chamber experiments and single particle levitation studies. The chambers used in both aspects will be coupled to investigate the impacts of aerosol transformation conditions on warm and cold cloud formation, using the instrumental payload from both chambers. A range of detailed models will be used to explicitly describe the processes by which aerosol particles interact with increasing relative humidity and reducing temperature to form cloud droplet and ice crystals and to their properties. The processes and properties will be represented in dynamical frameworks to predict the interactions between aerosols and clouds and their radiative effects at cloud resolving scales and radiative forcing of some of the investigated properties on global radiative forcing and feedbacks. The sensitivity of climate relevant parameters to the fundamental parameters investigated in the laboratory programme and their improved quantification will be evaluated using a simplified model 'emulator'.

气溶胶颗粒充当云滴和冰颗粒形成的场所。人为和自然过程向大气中添加气溶胶颗粒可能会扰乱云的特性。这种添加会影响云的微物理特性，进而影响云的动力学和热力学，以及云与辐射相互作用的方式。地球的辐射预算受云的影响非常大，而人为引起的影响云的粒子负荷的变化（称为间接效应）是巨大且高度不确定的。这种不确定性很大程度上是由于对气溶胶和云的基本属性和过程了解不足，导致它们在模型中的代表性较差。这里提出的研究计划是：i) 在实验室中直接调查这些过程，ii) 评估气候相关参数对所研究过程的敏感性，iii) 通过详细的模型调查解释实验室研究，以及 iv) 纳入和测试新的过程对云规模以及可能的全球规模模型中研究过程的描述。因此，该计划将减少与气溶胶和云过程相关的辐射强迫和气候反馈估计的不确定性。这些研究分为影响暖云（仅包含液滴）的研究和影响包含冰粒的云的研究。该计划汇集了一支跨学科研究人员团队，他们在“暖”和“冷”云和气溶胶过程方面具有专业知识，结合实验室和多尺度建模活动，以提供改进的预测能力。 “温暖”实验室工作重点关注两个主要方面：i) 气溶胶颗粒在变成云滴（或“激活”）时被生长的气溶胶颗粒吸收水的速率；ii) 不同成分的气溶胶颗粒充当种子的能力对于云滴。这些研究使用了多种技术，包括单粒子光学悬浮和在大型光化学室中进行的研究，以及模拟大气化学过程中形成的粒子群的大量化学和物理探针。这项“冷”工作使用了类似的大型、仪器齐全的云室实验和单粒子悬浮研究的结合。这两个方面使用的室将结合起来，利用两个室的仪器有效载荷来研究气溶胶转化条件对暖云和冷云形成的影响。将使用一系列详细模型来明确描述气溶胶颗粒与相对湿度增加和温度降低相互作用形成云滴和冰晶的过程及其特性。这些过程和特性将在动力学框架中表示，以预测气溶胶和云之间的相互作用及其在云解析尺度上的辐射效应，以及一些研究的全球辐射强迫和反馈特性的辐射强迫。气候相关参数对实验室计划中研究的基本参数的敏感性及其改进的量化将使用简化模型“模拟器”进行评估。

项目成果

Saturation vapor pressures and transition enthalpies of low-volatility organic molecules of atmospheric relevance: from dicarboxylic acids to complex mixtures.

与大气相关的低挥发性有机分子的饱和蒸气压和转变焓：从二羧酸到复杂混合物。

• DOI: http://dx.10.1021/cr5005502
• 发表时间: 2015
• 期刊: Chemical reviews
• 影响因子: 62.1
• 作者: Bilde M

A parameterisation for the activation of cloud drops including the effects of semi-volatile organics

云滴激活的参数化，包括半挥发性有机物的影响

• DOI: http://dx.10.5194/acp-14-2289-2014
• 发表时间: 2014
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Connolly P

Factors determining the most efficient spray distribution for marine cloud brightening

决定海洋云增亮最有效喷雾分布的因素

• DOI: http://dx.10.1098/rsta.2014.0056
• 发表时间: 2014
• 期刊: Mathematical, Physical and Engineering Sciences
• 作者: Connolly P

Critical assessment of liquid density estimation methods for multifunctional organic compounds and their use in atmospheric science.

多功能有机化合物液体密度估计方法的批判性评估及其在大气科学中的应用。

• DOI: http://dx.10.1021/jp304547r
• 发表时间: 2013
• 期刊: The journal of physical chemistry. A
• 作者: Barley MH

The effect of photochemical ageing and initial precursor concentration on the composition and hygroscopic properties of ß-caryophyllene secondary organic aerosol

光化学老化和初始前驱体浓度对α-石竹烯二次有机气溶胶组成和吸湿性能的影响

• DOI: http://dx.10.5194/acp-12-6417-2012
• 发表时间: 2012
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Alfarra M