气候变化领域集成服务门户(CCPortal): A perturbed parameter ensemble of HadGEM3-GC3.05 coupled model projections: part 2: global performance and future changes

CCPortal

DOI	10.1007/s00382-020-05608-5
	A perturbed parameter ensemble of HadGEM3-GC3.05 coupled model projections: part 2: global performance and future changes
	Yamazaki K.; Sexton D.M.H.; Rostron J.W.; McSweeney C.F.; Murphy J.M.; Harris G.R.
发表日期	2021
ISSN	0930-7575
起始页码	1609
结束页码	1624
卷号	56 期号:2021-11-12
英文摘要	This paper provides a quantitative assessment of large-scale features in a perturbed parameter ensemble (PPE) of Met Office Unified Model HadGEM-GC3.05 in coupled global historical and future simulations. The main motivation for the simulations is to provide a major component of the UK Climate Projections 2018 (UKCP18), but they will also be used to make worldwide projections and inform future model development. Initially, a 25-member PPE, with 25 different parameter combinations, was simulated. Five members were subsequently dropped because either their simulated climate was unrealistically cool by 1970 or they suffered from numerical instabilities. The remaining 20 members were evaluated after completing the historical phase (1900–2005) against 13 separately selected Climate Model Intercomparison Project Phase 5 (CMIP5) models, and five more members were dropped. The final product is a combined projection system of 15 PPE members and 13 CMIP5 models, which has a number of benefits. In particular, the range of outcomes available from the combined set of 28 is often larger than from either of the two constituent ensembles, thus providing users with a more complete picture of plausible impacts. Here we mainly describe the evaluation process of the 20 PPE members. We evaluate biases in a number of important properties of the global coupled system, including assessment of climatological averages, coupled modes of internal variability and historical and future changes. The parameter combinations yielded plausible yet diverse atmosphere and ocean model behaviours. The range of global temperature changes is narrow, largely driven by use of different CO2 pathways. The range of global warming is seemingly not linked to range of feedbacks estimated from atmosphere-only runs, though we caution that the range of the latter is narrow relative to CMIP5, and therefore this result is not unexpected. This is the second of two papers describing the generation of the PPE for UKCP18 projections. Part 1 (Sexton et al. 2021) describes the selection of 25 parameter combinations of 47 atmosphere and land surface parameters, using a set of cheap atmosphere-only runs at a coarser resolution from nearly 3000 samples of parameter space. © 2021, Crown.
英文关键词	Coupled global climate model; Diversity; Ensemble climate prediction; Global projections; Model evaluation; Perturbed parameter ensembles
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/183246
作者单位	Met Office Hadley Centre, FitzRoy Road, Exeter, EX1 3PB, United Kingdom
推荐引用方式 GB/T 7714	Yamazaki K.,Sexton D.M.H.,Rostron J.W.,et al. A perturbed parameter ensemble of HadGEM3-GC3.05 coupled model projections: part 2: global performance and future changes[J],2021,56(2021-11-12).
APA	Yamazaki K.,Sexton D.M.H.,Rostron J.W.,McSweeney C.F.,Murphy J.M.,&Harris G.R..(2021).A perturbed parameter ensemble of HadGEM3-GC3.05 coupled model projections: part 2: global performance and future changes.Climate Dynamics,56(2021-11-12).
MLA	Yamazaki K.,et al."A perturbed parameter ensemble of HadGEM3-GC3.05 coupled model projections: part 2: global performance and future changes".Climate Dynamics 56.2021-11-12(2021).