HALO 2020 – Cloud effects on solar actinic radiation: Evaluation of satellite-aided radiative transfer model calculations with HALO measurements

HALO 2020 â 云对太阳光化辐射的影响：利用 HALO 测量评估卫星辅助辐射传输模型计算

• 批准号: 442647232
• 负责人: Dr. Birger Bohn
• 金额: --
• 依托单位: IEK-8: Troposphäre
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/442647232?language=en
• 关键词: HALO; 2020; Cloud; effects; solar

In this project UV/VIS spectral actinic flux density measurements of six HALO missions will be used for an evaluation of radiative transfer model calculations based on operational satellite cloud retrievals. Five of the HALO missions have already been completed: TECHNO (2010), NARVAL-I (2014), OMO (2015), EMERGE (2017/2018), and CAFE-Africa (2018) with a total of around 75 research flights. In addition, data of CAFE-Brazil (2020) will be included. The main purpose of the spectral actinic flux density measurements is to derive photolysis frequencies that are important for photochemical research. The HALO measurements provide a rare opportunity for an evaluation of satellite derived photolysis frequencies because they provide high resolution spot samples that cover different altitudes and mission areas globally. Moreover, during TECHNO, NARVAL and OMO also nadir spectral radiance measurements were performed on HALO by a mission partner. These measurements cover the complete solar spectral range and provide independent, local information on cloud properties below the aircraft. That will help to interpret and correctly apply the satellite data. The main question addressed in this project is whether or not radiative transfer modelled and measured data can be brought into reasonable agreement by taking into account available satellite cloud information and if consistent results are obtained for different mission areas and altitude ranges. If this approach is successful, predictions of evaluated, user-defined 3D fields of photolysis frequencies and their error estimates can be produced based on satellite cloud information. These photolysis frequency fields can be used to test chemistry transport model predictions or they can serve directly as an input for such models in future studies. A corresponding case study is intended within this project. From these applications also future HALO missions and their scientific analyses could benefit.

在这个项目中，将利用六次HALO飞行任务的紫外/可见光光谱光化通量密度测量来评估基于业务卫星云的辐射传输模型计算。5次Halo飞行任务已经完成：Techno(2010)、NARVAL-I(2014)、OMO(2015)、Emerge(2017/2018)和CAFE-Africa(2018)，总共进行了约75次研究飞行。此外，还将包括巴西CAFE(2020)的数据。光谱光化通量密度测量的主要目的是得出对光化学研究很重要的光解频率。HALO测量为评估卫星产生的光解频率提供了难得的机会，因为它们提供了覆盖全球不同高度和任务区域的高分辨率斑点样本。此外，在TECHO、NARVAL和OMO期间，一个飞行任务伙伴还在HALO上进行了NADIR光谱辐射测量。这些测量覆盖了整个太阳光谱范围，并提供了有关飞机下方云层特性的独立、局部信息。这将有助于解释和正确应用卫星数据。该项目涉及的主要问题是，通过考虑到现有的卫星云信息，是否能够使模拟和测量的辐射传输数据达到合理的一致性，并在不同的任务区和高度范围内获得一致的结果。如果这种方法是成功的，就可以根据卫星云信息来预测评估的、用户定义的光解频率3D场及其误差估计。这些光解频率场可以用来测试化学传输模型的预测，或者它们可以在未来的研究中直接作为此类模型的输入。在该项目中还打算进行相应的案例研究。未来的光环飞行任务及其科学分析也可以从这些应用中受益。