Sustainability: Atmospheric Physics Needs for Community Climate Modeling

可持续性：社区气候建模所需的大气物理

• 批准号: 2311376
• 负责人: Isla Simpson
• 金额: $ 99.87万
• 依托单位: University Corporation For Atmospheric Res
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-15 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2311376&HistoricalAwards=false
• 关键词: Sustainability; Atmospheric; Physics; Needs; Community

Earth System Models (ESMs) serve a range of purposes. Cutting edge ESMs are used to generate climate projections for the coming decades, but they are also used as tools by the research community to gain understanding of processes and interactions that occur within the Earth System. The cutting-edge components of ESMs continue to grow in complexity and computational expense, which is a necessary evolution for improving state-of-the-art projections of future climate, but at the same time, this reduces the ability of researchers with limited computational resources to perform targeted experiments to address their problem of interest. As such, there is an important role to be played by computationally streamlined, yet still realistic, options within ESMs. The Community Earth System Model (CESM) is an ESM that is widely used within the research community of the USA and worldwide. The aims of CESM are not only to produce cutting edge climate projections but to provide the necessary tools to the research community to gain fundamental understanding of the behavior of the Earth System. The atmospheric component of CESM (the Community Atmosphere Model, CAM) is one of the most computationally expensive components of CESM. CAM is moving toward a new framework for connecting physical parameterizations to the host model in order to simplify the implementation of new physics packages moving forward. However, this means that some physical parameterizations that can be used to build a cheaper atmospheric model for gaining fundamental understanding will be lost, unless they can be refactored to be compatible with this new framework. This work will refactor previous generations of atmospheric physics packages within CAM to allow them to remain functional within CESM and continue to be used as an important resource for researchers worldwide. This refactoring will be accompanied by the development of documentation and tutorials that will allow users to configure and set up their model simulations with their own choices of physical parameterizations that can balance complexity, with computational expense, to suit their needs. This will allow CESM to continue to support a broad and diverse user base and to provide an educational tool that can allow individuals to gain a hands-on climate modeling experience at minimal computational expense.The Common Community Physics Package (CCPP) is a framework that is designed to facilitate the implementation of physics suites or individual parameterizations in atmospheric models. CAM is moving toward exclusive use of this framework in the near future which means that any physical parameterizations that are not refactored to be compatible with CCPP will no longer be available to the research community within CESM. This work will refactor the key components of previous generations of CAM physics (CAM4 and CAM5) to allow researchers to continue to build atmospheric configurations that are scientifically close to CAM4 and CAM5 and/or mix and match their capabilities together with newer physical parameterizations. This will ensure that these physical parameterizations remain functional within CESM, thereby retaining them as important, yet computationally streamlined, research tools for the Earth System research community. The CCPP framework contains a library of physical parameterizations that conforms to selected standards, and an infrastructure that enables connection of these parameterizations to the host model. This project will port CAM4 and CAM5 physics parameterizations to the CCPP framework. Part of this process is to implement explicit interfaces where variables passed in/out of the parameterization are defined in a variable dictionary since the parameterization can no longer access shared memory spaces between physics parameterizations (known as pbuf’s in CAM) and all variables must be passed explicitly. Hence it will be clear to the user exactly what variables a parameterization is using (and if there are implicit dependencies to other parameterizations) to ultimately provide tendencies back to the host model. To accompany the implementation of these physical parameterizations within CCPP, documentation and tutorials will be developed that will allow users to configure and set up model configurations that closely resemble CAM4 or CAM5 or to mix and match different physical parameterizations to suite their purpose, thereby filling out the atmospheric model hierarchy to support a broad range of research purposes.This award by the Office of Advanced Cyberinfrastructure is jointly supported by the Division of Atmospheric and Geospace Sciences within the Directorate for Geosciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

地球系统模型（ESM）有一系列的用途。先进的ESM被用于生成未来几十年的气候预测，但它们也被研究界用作工具，以了解地球系统内发生的过程和相互作用。ESM的尖端组件的复杂性和计算费用不断增加，这是改善未来气候最新预测的必要发展，但与此同时，这降低了计算资源有限的研究人员的能力。进行有针对性的实验来解决他们感兴趣的问题。因此，在紧急保障措施中，计算上经过简化但仍然现实的备选办法可以发挥重要作用。社区地球系统模型（Community Earth System Model，CESM）是一种在美国和世界范围内广泛使用的ESM。CESM的目标不仅是做出最前沿的气候预测，而且是为研究界提供必要的工具，以获得对地球系统行为的基本了解。社区大气模式（Community Atmosphere Model，CAM）是CESM中计算量最大的部分。CAM正在朝着一个新的框架发展，用于将物理参数化连接到主模型，以简化新物理包的实现。然而，这意味着一些可用于构建更便宜的大气模型以获得基本理解的物理参数化将丢失，除非它们可以重构以与这个新框架兼容。这项工作将在CAM中重构前几代大气物理学软件包，使其能够在CESM中保持功能，并继续作为全球研究人员的重要资源。这种重构将伴随着文档和教程的开发，这些文档和教程将允许用户通过自己选择的物理参数化来配置和设置他们的模型模拟，这些物理参数化可以平衡复杂性和计算费用，以满足他们的需求。这将使CESM能够继续支持广泛和多样化的用户群，并提供一个教育工具，使个人能够以最小的计算费用获得实际的气候建模经验，共同社区物理包（CCPP）是一个框架，旨在促进大气模型中物理套件或个人参数化的实施。CAM正在朝着在不久的将来独家使用这个框架，这意味着任何物理参数化，没有重构，以兼容CCPP将不再提供给CESM内的研究社区。这项工作将重构前几代CAM物理学（CAM 4和CAM 5）的关键组件，使研究人员能够继续构建在科学上接近CAM 4和CAM 5的大气配置，并/或将其功能与更新的物理参数化相结合。这将确保这些物理参数化在CESM中保持功能，从而保留它们作为地球系统研究界重要但计算精简的研究工具。CCPP框架包含符合选定标准的物理参数化库，以及支持将这些参数化连接到主机模型的基础设施。该项目将CAM4和CAM 5物理参数化移植到CCPP框架中。这个过程的一部分是实现显式接口，其中传入/传出参数化的变量在变量字典中定义，因为参数化不再可以访问物理参数化之间的共享内存空间（在CAM中称为pbuf），并且所有变量都必须显式传递。因此，用户将清楚地知道参数化正在使用哪些变量（以及是否存在对其他参数化的隐式依赖关系），以最终将趋势提供回主机模型。为了在CCPP中实现这些物理参数化，将开发文档和教程，允许用户配置和设置与CAM 4或CAM 5非常相似的模型配置，或混合和匹配不同的物理参数化以满足其目的，从而填补了大气模型的层次结构，以支持广泛的研究目的。该奖项由高级网络基础设施办公室该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。