气候变化领域集成服务门户(CCPortal): An Objective and Efficient Method for Assessing the Impact of Reduced-Precision Calculations On Solution Correctness

CCPortal

DOI	10.1029/2019MS001817
	An Objective and Efficient Method for Assessing the Impact of Reduced-Precision Calculations On Solution Correctness
	Zhang S.; Wan H.; Rasch P.J.; Singh B.; Larson V.E.; Woodward C.S.
发表日期	2019
ISSN	19422466
起始页码	3131
结束页码	3147
卷号	11 期号:10
英文摘要	Recent studies have shown that reducing the precision of floating-point calculations in an atmospheric model can improve the model's computational performance without affecting model fidelity, but code changes are needed to accommodate lower precision or to prevent undue round-off error. For complex and computationally expensive systems like the Energy Exascale Earth System Model, a method is needed to objectively and efficiently assess the quality of the lower-precision simulations and to quickly identify problematic code pieces. This paper demonstrates that the accuracy of the computed solution can be evaluated through a simple and quantitative error metric based on time step convergence. The proposed test method can unambiguously detect the accumulation of precision error and objectively assess its impact on solution accuracy. Furthermore, since fast physical processes are known to affect key features of the multiyear mean climate in atmospheric models, we show that the convergence test applied to short simulations can provide useful information about the impact of reduced precision on a model's long-term behavior. In contrast, the traditional method of climate model evaluation requires multiple years of simulations and involves inspecting many physical quantities for statistical significance in the presence of natural variability. The simplicity, computational efficiency, and objectivity of the proposed method makes it very attractive for high-resolution model development. The method is also expected to be applicable to other models that numerically solve time evolution equations. ©2019. The Authors.
英文关键词	high-performance computing; numerical solution; solution convergence; time integration; verification
语种	英语
scopus关键词	Computational efficiency; Digital arithmetic; Errors; Verification; Computational performance; Floating-point calculations; High performance computing; High-resolution models; Numerical solution; Statistical significance; Time evolution equations; Time integration; Climate models; climate modeling; Earth science; numerical model; parameterization; precision
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/156850
作者单位	Pacific Northwest National Laboratory, Richland, WA, United States; Department of Mathematical Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, United States; Lawrence Livermore National Laboratory, Livermore, CA, United States
推荐引用方式 GB/T 7714	Zhang S.,Wan H.,Rasch P.J.,et al. An Objective and Efficient Method for Assessing the Impact of Reduced-Precision Calculations On Solution Correctness[J],2019,11(10).
APA	Zhang S.,Wan H.,Rasch P.J.,Singh B.,Larson V.E.,&Woodward C.S..(2019).An Objective and Efficient Method for Assessing the Impact of Reduced-Precision Calculations On Solution Correctness.Journal of Advances in Modeling Earth Systems,11(10).
MLA	Zhang S.,et al."An Objective and Efficient Method for Assessing the Impact of Reduced-Precision Calculations On Solution Correctness".Journal of Advances in Modeling Earth Systems 11.10(2019).