A dual perspective on cloud-aerosol-radiation interaction using novel polarimetric and hyper-spectral measurements

使用新型偏振和高光谱测量的云-气溶胶-辐射相互作用的双重视角

• 批准号: 264269520
• 负责人: Dr. Claudia Emde
• 金额: --
• 依托单位: SRON - Netherlands Institute for Space Research
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/264269520?language=en
• 关键词: dual; perspective; cloud; aerosol; radiation

Interaction of clouds and aerosols is a wide field of open questions highly relevant to the atmospheric scientific community. IPCC (2014) recognizes the need for additional scientific efforts to disentangle the variety of interacting processes and their role in a changing climate. This proposal aims at developing and testing a novel concept for remote sensing of the aerosol-cloud interaction. Aerosols have direct effects on the radiation budget and they cause indirect effects by alteration of cloud microphysics and subsequent effects on cloud dynamics, precipitation, cloud lifetime, water cycle, and even changes on regional and global circulation patterns. Aerosol itself is affected by clouds: Aerosol properties and spatial distribution are affected by swelling of particles as well as by dynamical and chemical processes in the cloud. The concentration of activated cloud condensation nuclei (CCNC) plays a crucial role. CCNC can be directly determined by in-situ measurements with limited coverage. However, they cannot be measured quantitatively by conventional optical remote sensing methods since their size range is far below the wavelengths of visible radiation. For that reason an alternative concept was proposed: Cloud side measurements, measuring spectral solar radiance reflected at cloud sides, aim at deriving profiles of cloud particle size and phase. It was hypothesized that these observations allow to study the impact of aerosol on vertical development of cloud microphysics, and even to derive CCNC. CCNC may also be derived directly from aerosol optical property measurements. Correlations between them and CCNC have been identified, however, with significant uncertainy. This proposal aims at bringing together these two approaches to test the involved hypotheses. Fast scanning spectral observations will be key to address these issues, since clouds change rapidly in time. For the purpose of this project, a hyper-spectral imager will be equipped with polarization capability. With the same instrumentation derivation of microphysical properties of convective clouds as well as aerosol optical properties in the cloudless sky in between is aimed at. The work is structured into two PhD projects. Highlights 1) Test of two hypotheses which are key for the development of aircraft and proposed satellite remote sensing missions: Can CCN concentration be derived from remote sensing of aerosol properties and cloud microphysics profiles? 2) Rapid hyper-spectral scanning allows for microphysics retrievals of changing clouds; it will be tested if this information allows deriving changes of microphysical properties with distance from the cloud edge. 3) Retrieval of aerosol from polarized hyper-spectral radiance observations in presence of clouds will be expored.

云和气溶胶的相互作用是一个与大气科学界高度相关的广泛开放问题。IPCC（2014）认识到需要更多的科学努力来理清各种相互作用的过程及其在气候变化中的作用。该提案旨在开发和测试一种遥感气溶胶-云相互作用的新概念。气溶胶对辐射收支有直接影响，并通过改变云的微物理特性和随后对云动力学、降水、云寿命、水循环的影响，甚至对区域和全球环流模式的变化产生间接影响。气溶胶本身受云的影响：气溶胶的性质和空间分布受到粒子膨胀以及云中动力学和化学过程的影响。激活云凝结核（CCNC）的浓度起着至关重要的作用。CCNC可以直接通过现场测量有限的覆盖范围来确定。然而，它们无法通过常规光学遥感方法进行定量测量，因为它们的尺寸范围远低于可见光辐射的波长。为此，提出了另一种概念：云侧测量，测量在云侧反射的光谱太阳辐射，旨在获得云粒子大小和相位的轮廓。据推测，这些观测可以研究气溶胶对云微物理垂直发展的影响，甚至推导出CCNC。CCNC也可以直接从气溶胶光学性质测量导出。然而，它们与CCNC之间的相关性已被确定，具有很大的不确定性。本建议旨在将这两种方法结合起来，以检验所涉及的假设。快速扫描光谱观测将是解决这些问题的关键，因为云的变化很快。为了该项目的目的，将配备一台具有偏振能力的超光谱成像仪。利用相同的仪器，推导出对流云的微物理特性以及其间无云天空中的气溶胶光学特性。这项工作分为两个博士项目。亮点1）测试两个假设，这是关键的飞机和拟议的卫星遥感任务的发展：CCN浓度可以从遥感气溶胶特性和云微物理廓线？2)快速超光谱扫描可用于对变化中的云进行微物理学检索;将测试这一信息是否可用于推导出云的微物理特性随离云边缘的距离而发生的变化。3)将讨论在有云的情况下从偏振超光谱辐射观测反演气溶胶的问题。

项目成果

Retrieval of aerosol properties from ground-based polarimetric sky-radiance measurements under cloudy conditions

多云条件下从地面偏振天空辐射测量中检索气溶胶特性

• DOI: 10.1016/j.jqsrt.2019.02.025
• 发表时间: 2019
• 期刊: Journal of Quantitative Spectroscopy and Radiative Transfer
• 影响因子: 2.3
• 作者: H. Grob;C. Emde;B. Mayer
• 通讯作者: B. Mayer

The challenge of simulating the sensitivity of the Amazonian cloud microstructure to cloud condensation nuclei number concentrations

• DOI: 10.5194/acp-20-1591-2020
• 发表时间: 2020-02
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: P. Polonik;C. Knote;T. Zinner;Florian Ewald;T. Kölling;B. Mayer;M. Andreae;T. Jurkat-Witschas;T. Klimach;C. Mahnke;S. Molleker;C. Pöhlker;M. Pöhlker;U. Pöschl;D. Rosenfeld;C. Voigt;R. Weigel;M. Wendisch

The polarized sun and sky radiometer SSARA: design, calibration, and application for ground based aerosol remote sensing

• DOI: 10.5194/amt-2019-226
• 发表时间: 2019
• 期刊: Journal of Quantitative Spectroscopy and Radiative Transfer
• 影响因子: 2.3
• 作者: H. Grob;C. Emde;M. Wiegner;M. Seefeldner;B. Mayer

Aircraft-based stereographic reconstruction of 3-D cloud geometry

基于飞机的 3D 云几何形状的立体重建

• DOI: 10.5194/amt-12-1155-2019
• 发表时间: 2019
• 期刊: Atmospheric Measurement Techniques
• 影响因子: 3.8
• 作者: T. Kölling;T. Zinner;B. Mayer
• 通讯作者: B. Mayer

Remote sensing of cloud droplet radius profiles using solar reflectance from cloud sides – Part 1: Retrieval development and characterization

• DOI: 10.5194/amt-12-1183-2019
• 发表时间: 2019-02
• 期刊: Atmospheric Measurement Techniques
• 影响因子: 3.8
• 作者: Florian Ewald;T. Zinner;T. Kölling;B. Mayer