气候变化领域集成服务门户(CCPortal): Performance and Accuracy Implications of Parallel Split Physics-Dynamics Coupling in the Energy Exascale Earth System Atmosphere Model

CCPortal

DOI	10.1029/2020MS002080
	Performance and Accuracy Implications of Parallel Split Physics-Dynamics Coupling in the Energy Exascale Earth System Atmosphere Model
	Donahue A.S.; Caldwell P.M.
发表日期	2020
ISSN	19422466
卷号	12 期号:7
英文摘要	Simultaneous calculation of atmospheric processes is faster than calculating processes one at a time. This type of parallelism is beneficial or perhaps even necessary to provide good performance on modern supercomputers, which achieve faster performance through increased processor count rather than improved clock speed. The scalability of the Energy Exascale Earth System Model (E3SM) Atmosphere Model (EAM) is limited by the fluid dynamics which scales up to the number of mesh cells in the global mesh. In contrast, the suite of physics parameterizations in EAM is scalable up to the total number of physics columns, which is an order of magnitude greater than the number of mesh cells. A proposed solution to unlocking the greater potential performance from the physics suite is to solve the physics and dynamics in parallel. This work represents a first attempt at parallel splitting of the grid-scale fluid dynamics model and the subgrid-scale physics parameterizations in a global atmosphere model. We will demonstrate that switching to parallel physics-dynamics coupling extends the scalability of the EAM to up to 3 times the previous peak scalability limit and is up to 20% faster than the sequentially split coupling at the highest core counts and the same time step. Decadal simulations of both coupling approaches show very little impact to the model climate. This improved performance does not come without drawbacks, however. Parallel splitting requires a shorter time step and other modifications which largely offset performance gains. A mass fixer is required for conservation. Techniques for mitigating these issues are also discussed. ©2020. The Authors.
英文关键词	computational performance; global atmosphere modeling; numerical stability; parallel splitting; physics-dynamics coupling; time stepping
语种	英语
scopus关键词	Earth atmosphere; Fluid dynamics; Mesh generation; Scalability; Supercomputers; Atmosphere modeling; Atmospheric process; Dynamics coupling; Earth system model; Fluid dynamics model; Parallel split; Parallel splitting; Performance Gain; Climate models; accuracy assessment; atmospheric circulation; atmospheric modeling; decadal variation; fluid dynamics; parameterization; performance assessment
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156699
作者单位	Lawrence Livermore National Laboratory, Livermore, CA, United States
推荐引用方式 GB/T 7714	Donahue A.S.,Caldwell P.M.. Performance and Accuracy Implications of Parallel Split Physics-Dynamics Coupling in the Energy Exascale Earth System Atmosphere Model[J],2020,12(7).
APA	Donahue A.S.,&Caldwell P.M..(2020).Performance and Accuracy Implications of Parallel Split Physics-Dynamics Coupling in the Energy Exascale Earth System Atmosphere Model.Journal of Advances in Modeling Earth Systems,12(7).
MLA	Donahue A.S.,et al."Performance and Accuracy Implications of Parallel Split Physics-Dynamics Coupling in the Energy Exascale Earth System Atmosphere Model".Journal of Advances in Modeling Earth Systems 12.7(2020).