气候变化领域集成服务门户(CCPortal): Pacific variability reconciles observed and modelled global mean temperature increase since 1950

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DOI	10.1007/s00382-020-05493-y
	Pacific variability reconciles observed and modelled global mean temperature increase since 1950
	Stolpe M.B.; Cowtan K.; Medhaug I.; Knutti R.
发表日期	2020
ISSN	0930-7575
英文摘要	Global mean temperature change simulated by climate models deviates from the observed temperature increase during decadal-scale periods in the past. In particular, warming during the ‘global warming hiatus’ in the early twenty-first century appears overestimated in CMIP5 and CMIP6 multi-model means. We examine the role of equatorial Pacific variability in these divergences since 1950 by comparing 18 studies that quantify the Pacific contribution to the ‘hiatus’ and earlier periods and by investigating the reasons for differing results. During the ‘global warming hiatus’ from 1992 to 2012, the estimated contributions differ by a factor of five, with multiple linear regression approaches generally indicating a smaller contribution of Pacific variability to global temperature than climate model experiments where the simulated tropical Pacific sea surface temperature (SST) or wind stress anomalies are nudged towards observations. These so-called pacemaker experiments suggest that the ‘hiatus’ is fully explained and possibly over-explained by Pacific variability. Most of the spread across the studies can be attributed to two factors: neglecting the forced signal in tropical Pacific SST, which is often the case in multiple regression studies but not in pacemaker experiments, underestimates the Pacific contribution to global temperature change by a factor of two during the ‘hiatus’; the sensitivity with which the global temperature responds to Pacific variability varies by a factor of two between models on a decadal time scale, questioning the robustness of single model pacemaker experiments. Once we have accounted for these factors, the CMIP5 mean warming adjusted for Pacific variability reproduces the observed annual global mean temperature closely, with a correlation coefficient of 0.985 from 1950 to 2018. The CMIP6 ensemble performs less favourably but improves if the models with the highest transient climate response are omitted from the ensemble mean. © 2020, The Author(s).
英文关键词	CMIP5; CMIP6; Decadal variability; ENSO; Global mean temperature; Internal variability
语种	英语
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/145666
作者单位	Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland; Department of Chemistry, University of York, York, United Kingdom
推荐引用方式 GB/T 7714	Stolpe M.B.,Cowtan K.,Medhaug I.,et al. Pacific variability reconciles observed and modelled global mean temperature increase since 1950[J],2020.
APA	Stolpe M.B.,Cowtan K.,Medhaug I.,&Knutti R..(2020).Pacific variability reconciles observed and modelled global mean temperature increase since 1950.Climate Dynamics.
MLA	Stolpe M.B.,et al."Pacific variability reconciles observed and modelled global mean temperature increase since 1950".Climate Dynamics (2020).