气候变化领域集成服务门户(CCPortal): Number Formats, Error Mitigation, and Scope for 16-Bit Arithmetics in Weather and Climate Modeling Analyzed With a Shallow Water Model

CCPortal

DOI	10.1029/2020MS002246
	Number Formats, Error Mitigation, and Scope for 16-Bit Arithmetics in Weather and Climate Modeling Analyzed With a Shallow Water Model
	Klöwer M.; Düben P.D.; Palmer T.N.
发表日期	2020
ISSN	19422466
卷号	12 期号:10
英文摘要	The need for high-precision calculations with 64-bit or 32-bit floating-point arithmetic for weather and climate models is questioned. Lower-precision numbers can accelerate simulations and are increasingly supported by modern computing hardware. This paper investigates the potential of 16-bit arithmetic when applied within a shallow water model that serves as a medium complexity weather or climate application. There are several 16-bit number formats that can potentially be used (IEEE half precision, BFloat16, posits, integer, and fixed-point). It is evident that a simple change to 16-bit arithmetic will not be possible for complex weather and climate applications as it will degrade model results by intolerable rounding errors that cause a stalling of model dynamics or model instabilities. However, if the posit number format is used as an alternative to the standard floating-point numbers, the model degradation can be significantly reduced. Furthermore, mitigation methods, such as rescaling, reordering, and mixed precision, are available to make model simulations resilient against a precision reduction. If mitigation methods are applied, 16-bit floating-point arithmetic can be used successfully within the shallow water model. The results show the potential of 16-bit formats for at least parts of complex weather and climate models where rounding errors would be entirely masked by initial condition, model, or discretization error. © 2020. The Authors.
英文关键词	16-bit arithmetic; climate models; floating-point numbers; posit numbers; Reduced precision; rounding error
语种	英语
scopus关键词	Climate change; Digital arithmetic; Errors; Computing hardware; Discretization errors; Floating point numbers; Initial conditions; Mitigation methods; Model degradations; Shallow water model; Weather and climate models; Climate models; climate conditions; climate modeling; model; precision; shallow water
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/156619
作者单位	Atmospheric, Oceanic and Planetary Physics, University of Oxford, Oxford, United Kingdom; European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom
推荐引用方式 GB/T 7714	Klöwer M.,Düben P.D.,Palmer T.N.. Number Formats, Error Mitigation, and Scope for 16-Bit Arithmetics in Weather and Climate Modeling Analyzed With a Shallow Water Model[J],2020,12(10).
APA	Klöwer M.,Düben P.D.,&Palmer T.N..(2020).Number Formats, Error Mitigation, and Scope for 16-Bit Arithmetics in Weather and Climate Modeling Analyzed With a Shallow Water Model.Journal of Advances in Modeling Earth Systems,12(10).
MLA	Klöwer M.,et al."Number Formats, Error Mitigation, and Scope for 16-Bit Arithmetics in Weather and Climate Modeling Analyzed With a Shallow Water Model".Journal of Advances in Modeling Earth Systems 12.10(2020).