Computer Cluster for Numerical Modelling and Simulation

用于数值建模和仿真的计算机集群

• 批准号: 431063325
• 金额: --
• 依托单位: Universität Bremen
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/431063325?language=en
• 关键词: Computer; Cluster; Numerical; Modelling; Simulation

The working group Climate Geography focusses on numerical modeling of mountain glaciers on the regional and global scale, both for reconstructing past glacier dynamics, for producing projections and for conceptual studies of glacier-climate-interactions. The results are used for investigating the contribution of glaciers to seasonal water availability and for quantifying the contribution of glaciers to regional sea-level change. We also investigate societal consequences of these impacts of glacier change. Our work is based on the Open Global Glacier Model (OGGM, http://oggm.org), which is developed by the group with growing contributions from the international community. We further apply statistical and dynamical downscaling of the atmosphere to investigate interactions at the ice-air boundary, which are governed by the complex topography of mountain regions. Since the glaciers simulated by OGGM are not dynamically coupled, a global run of the model consists of a great number of independent processes, leading to very good scalability of the model. In principle, OGGM is therefore well suited to be deployed at regional/national high performance computation centers like HLRN. In practice, this is made impossible by the dependency of OGGM on a great number of external data sources, which are updated frequently and dynamically loaded from the internet. This is impossible at HLRN because of security considerations. Alternatively, data could be packaged and uploaded, which is impracticable because of the required amount of data (ca. 1 TB per global model run). Moreover, since OGGM is in very active development, it needs an up-to-date Python environment and frequent updates. This demand is incompatible with the compute centers’ (like HLRN) need for stability, which prevents users from getting direct control of the installed packages. Tests have shown that the dependence of OGGM on up-to-date software packages prevents its deployments at HLRN resources. Since model development is an important aspect of the ongoing work, local resources that can allocated and configured flexibly are needed. Finally, apart from the (well scalable) tasks of modeling a great number of individual glaciers, there are certain “global” tasks (mostly concerning model validation and optimization) that cannot be parallelized and thus need high maximum wall clock times. The compute cluster requested here is needed to secure the computational resources needed by the working group.

气候地理学工作组专注于区域和全球范围内的山地冰川数值模拟，以重建过去的冰川动态、进行预测以及冰川与气候相互作用的概念研究。结果用于调查冰川的贡献。我们还研究了冰川变化影响的社会后果。 （OGGM，http://oggm.org），它是由国际社会不断贡献的小组开发的，我们进一步应用大气的统计和动力学降尺度来研究冰-空气边界的相互作用，这些相互作用受由于 OGGM 模拟的冰川不是动态耦合的，因此模型的全局运行由大量独立的过程组成，因此原则上 OGGM 非常适合。成为实际上，由于 OGGM 依赖大量外部数据源（这些数据源经常更新并从互联网动态加载），因此这是不可能的，因为这在 HLRN 是不可能的。出于安全考虑，数据可以打包并上传，但由于所需的数据量（每个全局模型运行约 1 TB），这是不切实际的。此外，由于 OGGM 正处于非常积极的开发阶段，因此它需要一个最新的Python环境和频繁的更新与计算中心（如HLRN）对稳定性的需求不相容，这使得用户无法直接控制已安装的软件包。测试表明OGGM对up的依赖。最新的软件包阻碍了其在 HLRN 资源上的部署，因为模型开发是正在进行的工作的一个重要方面，因此除了建模大型任务（良好的可扩展性）之外，还需要能够灵活分配和配置的本地资源。数字对于单个冰川，存在某些无法并行化的“全局”任务（主要涉及模型验证和优化），因此需要较高的最大挂钟时间，以确保工作组所需的计算资源。