Understanding tropical cirrus by combining laboratory cloud simulation and field experiments with process and circulation modelling

通过将实验室云模拟和现场实验与过程和环流建模相结合来了解热带卷云

• 批准号: 392369854
• 负责人: Dr. Martina Krämer
• 金额: --
• 依托单位: Institut für Meteorologie und Geophysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/392369854?language=en
• 关键词: Understanding; tropical; cirrus; combining; laboratory

This project (TropiC) is part of the PIRE International Partnership for Cirrus Studies lead by the University of Chicago. The PIRE project brings together an international team of four US American and four European expert teams for coordinated studies to advance knowledge of thin, high-altitude cirrus clouds in the cold tropical transition layer (TTL), one of the least understood region in the atmosphere. Though optically thin and often not visible, these cold ice clouds play important roles in the atmosphere and the climate system. The PIRE project focuses on formation processes of cirrus clouds, their internal dynamics, as well as their interaction with atmospheric radiative and dynamic processes. The objectives of TropiC as part of PIRE are to study and better understand (1) the process details and roles of heterogeneous and homogeneous ice formation as a source for cirrus ice crystals, (2) the equilibrium and kinetic isotopic fractionation effects of water in mixed-phase and cirrus clouds, (3) the abundance patterns of ice crystals in cirrus layers, and (4) the representation and impact of tropical cirrus clouds in global and regional model setups.TropiC is a coordinated effort of laboratory, field and modelling activities of the Karlsruhe Institute of Technology (KIT) and the Forschungszentrum Jülich (FZJ). The work program includes well-controlled cloud simulation experiments in the AIDA cloud chamber facilities at KIT, the detailed analysis of cirrus in situ measurements during StratoClim and other field activities of FZJ, and modelling studies with the process models MAID (FZJ) and ACPIM (University of Manchester), the large-scale Lagrangian type model CLaMS-Ice (FZJ), the global model framework ICON GCM (KIT), as well as the observational and process models from the PIRE consortium partners in Europe and the U.S. Among the project deliverables are new model parameterizations of cirrus processes for cloud, weather and climate models, well characterized data sets of typical cirrus cases from observations during StratoClim and AIDA cloud experiments to be used by the PIRE modelling partners as a test bed for comparing different ice nucleation and cirrus formation schemes in models, and a set of global and regional ICON simulations of the present-day climate and of global warming for comparison with the high-resolution and large-scale modeling done within the PIRE consortium. Finally, the work within this project and the whole PIRE collaboration will lead to a well advanced process understanding of TTL cirrus formation, and an extended description of cirrus clouds in the most advanced atmospheric models. Therefore, regional and global models will more accurately simulate the occurrence of TTL cirrus and their role in a changing climate. As a service to the PIRE project, new PhD students and postdocs will be trained at the unique AIDA cloud chamber facility in experimental cloud process studies and related modelling.

这个项目（TropiC）是由芝加哥大学领导的PIRE国际卷云研究伙伴关系的一部分。PIRE项目汇集了一个由四个美国和四个欧洲专家小组组成的国际小组，进行协调研究，以提高对冷热带过渡层（TTL）中薄高空卷云的认识，TTL是大气中最不了解的区域之一。虽然光学薄，往往是不可见的，这些寒冷的冰云在大气和气候系统中发挥着重要作用。PIRE项目的重点是卷云的形成过程、卷云的内部动力学以及卷云与大气辐射和动力学过程的相互作用。作为PIRE的一部分，TropiC的目标是研究和更好地理解（1）作为卷云冰晶来源的非均质和均质冰形成的过程细节和作用，（2）混合相和卷云中水的平衡和动力学同位素分馏效应，（3）卷云层中冰晶的丰度模式，TropiC是卡尔斯鲁厄理工学院（KIT）和于利希研究中心（FZJ）的实验室、野外和模拟活动的协调努力。工作计划包括在KIT的AIDA云室设施中进行良好控制的云模拟实验，在StratoClim和FZJ的其他实地活动期间对卷云进行现场测量的详细分析，以及使用过程模型MAID（FZJ）和ACPIM进行建模研究（曼彻斯特大学）、大尺度拉格朗日型模式CLaMS-Ice（FZJ）、全球模式框架ICON GCM（KIT）、以及PIRE联盟在欧洲和美国的合作伙伴提供的观测和过程模型。项目交付的成果包括云、天气和气候模型的卷云过程的新模型参数化，在StratoClim和AIDA云实验期间观测到的典型卷云情况的特征良好的数据集，将由PIRE建模合作伙伴用作比较的试验台不同的冰成核和卷云形成模式，以及一套全球和区域ICON模拟当今气候和全球变暖，与高分辨率和大规模的模拟在PIRE财团内完成。最后，在这个项目和整个PIRE合作的工作将导致一个先进的TTL卷云形成过程的理解，并在最先进的大气模型卷云的扩展描述。因此，区域和全球模式将更准确地模拟TTL卷云的发生及其在气候变化中的作用。作为PIRE项目的一项服务，新的博士生和博士后将在独特的AIDA云室设施接受云过程实验研究和相关建模的培训。