Simulation of Microphysical Properties, Mesoscale Organization and Variability of Stratocumulus Clouds During the VOCALS Regional Experiment (REx)

海洋边界层(MBL)中的层积云(SC)是东南太平洋(SEP)气候系统的基石和地球辐射收支的重要调节器。SC云表现出广泛的性质和形态，并对该区域的整体中尺度变率有相当大的贡献。然而，控制MBL云中尺度变异性、影响其微物理和宏观物理性质以及气溶胶和云之间相互作用的机制还不是很清楚，没有得到很好的量化，甚至可能在现有的大尺度和中尺度模式中被错误地描述。主要目标是：(A)更好地了解导致观测到的微物理和宏观物理SC云特性中尺度可变性的微物理和动力学机制；(B)调查气溶胶和气溶胶-云相互作用在开放单体袋(POCs)的形成、中尺度组织和维持方面的作用；以及(C)改进区域模式中MBL云和气溶胶的微物理和宏观物理特性的表示。为了评估模式模拟和与观测的比较，我们将使用VAMOS海洋-云-大气-陆地研究(VOALS)区域实验(REX)和卫星观测的广泛多平台测量的组合。区域模式的模拟将允许中尺度变化，这通常对有组织的中尺度对流至关重要，但也允许现实世界情景的背景。因此，区域模式模拟将弥合大涡模拟和全球环流模式模拟之间的尺度差异所造成的差距。智力优势：对导致东南太平洋地区海洋边界层云观测到的中尺度变异性的微物理和动力学过程的理解有望得到改善。这一知识将对改进气溶胶-云相互作用的微物理参数化具有重要价值，因为VISION将在区域和全球模式中更好地表示海洋SC云的中尺度云可变性，这将有助于缩小全球气候系统中气溶胶间接影响和云反馈的不确定性。研究成果将通过在国家和国际讲习班和会议上的介绍来传播。该项目还将促进研究生教育和培训。与其他科学家合作，研究活动将有助于通过模型相互比较来改进区域模型和参与度。

Stratocumulus (Sc) clouds in the marine boundary layer (MBL) are a cornerstone of theSoutheast Pacific (SEP) climate system and important modulators of the Earth's radiation budget. Sc clouds exhibit a wide range of properties and morphologies and contribute considerably to the overall mesoscale variability of the region. However, the mechanisms that control the mesoscale variability of MBL clouds, influence their microphysical and macrophysical properties as well as the interactions between aerosols and clouds are poorly understood, not very well quantified and may even be misrepresented in current large-scale and mesoscale models.This project will focus upon the numerical simulation of marine boundary layer clouds in the SEP region. The major goals are (a) to better understand the microphysical and dynamical mechanisms that lead to the observed mesoscale variability of microphysical and macrophysical Sc cloud properties; (b) to investigate the role of aerosols and aerosol-cloud interactions for the formation, mesoscale organization and maintenance of pockets of open cells (POCs); and (c) to improve the representation of microphysical and macrophysical properties of MBL clouds as well as aerosols in a regional model. For the evaluation of the model simulations and the comparison with observations we will use a combination of extensive multi-platform measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study (VOCALS) Regional Experiment (REx) and satellite observations.The simulations with the regional model will permit mesoscale variability that typically is crucial for organized mesoscale convection, but also allow the context of a real world scenario. Thus, the regional model simulations will bridge the gap induced by the scale disparity between large eddy simulations and simulations with global circulation models.Intellectual merit:The expected improvement in understanding of the microphysical and dynamical processes leading to the observed mesoscale variability of marine boundary layer clouds in the Southeast Pacific region. This knowledge will be of great value for improving microphysical parameterizations of aerosol-cloud interactions with the vision to better represent mesoscale cloud variability of marine Sc clouds in regional and global models, which will then help to narrow down uncertainties of aerosol indirect effects and cloud feedbacks in the global climate system.Broader impacts:Newly acquired data sets will be made available at the NCAR EOL database and shared with the broader VOCALS community. Research results will be disseminated through presentations at national and international workshops and conferences. The project will also promote graduate education and training. Collaborating with other scientists, the research activity will help to improve regional models and participation via model intercomparison.