气候变化领域集成服务门户(CCPortal): Robustness and drivers of the Northern Hemisphere extratropical atmospheric circulation response to a CO 2 -induced warming in CNRM-CM6-1

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DOI	10.1007/s00382-019-05113-4
	Robustness and drivers of the Northern Hemisphere extratropical atmospheric circulation response to a CO 2 -induced warming in CNRM-CM6-1
	Oudar T.; Cattiaux J.; Douville H.; Geoffroy O.; Saint-Martin D.; Roehrig R.
发表日期	2020
ISSN	0930-7575
起始页码	2267
结束页码	2285
卷号	54
英文摘要	Understanding the mid-latitude atmospheric circulation response to CO2 forcing is challenging and complex due to the strong internal variability and the multiple potential CO2-induced effects. While a significant poleward shift of the jet is projected in summer, changes remain uncertain in winter. In this study, we investigate the boreal winter extratropical jet response to an abrupt quadrupling of atmospheric CO2 in the CMIP6-generation global climate model CNRM-CM6-1. First, we show that the model performs better than the former generation CNRM-CM5 model in representing the atmospheric dynamics in the northern extratropics. Then, when atmospheric CO2 is quadrupled, CNRM-CM6-1 exhibits a strengthening and upward shift of the jet. A poleward shift is identified and robust in the Pacific in boreal winter. In the Atlantic, the jet response rather exhibits a squeezing, especially at the eastern part of the basin. It is found that changes are more robust across the Northern Hemisphere in early-winter than in late-winter season. Finally, the circulation response is broken down into individual contributions of various drivers. The uniform global mean component of the SST warming is found to explain most of the total atmospheric response to a quadrupling of CO2, with relatively smaller contributions from faster CO2 effects, the SST pattern change and the Arctic sea ice decline. The cloud radiative effect contribution is also assessed and found to be rather weak in the CNRM-CM6-1 model. This study highlights that long experiments are required to isolate the wintertime circulation response from the internal variability, and that idealized experimental setups are helpful to disentangle the physical drivers. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	CNRM-CM6-1; CO2 increase; Eady growth rate; Jet position; Mid-latitude dynamics
语种	英语
scopus关键词	atmospheric circulation; carbon dioxide; carbon emission; climate change; global warming; Northern Hemisphere; summer; winter
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/145593
作者单位	CNRM, Université de Toulouse, Météo France, CNRS, Toulouse, France
推荐引用方式 GB/T 7714	Oudar T.,Cattiaux J.,Douville H.,et al. Robustness and drivers of the Northern Hemisphere extratropical atmospheric circulation response to a CO 2 -induced warming in CNRM-CM6-1[J],2020,54.
APA	Oudar T.,Cattiaux J.,Douville H.,Geoffroy O.,Saint-Martin D.,&Roehrig R..(2020).Robustness and drivers of the Northern Hemisphere extratropical atmospheric circulation response to a CO 2 -induced warming in CNRM-CM6-1.Climate Dynamics,54.
MLA	Oudar T.,et al."Robustness and drivers of the Northern Hemisphere extratropical atmospheric circulation response to a CO 2 -induced warming in CNRM-CM6-1".Climate Dynamics 54(2020).