气候变化领域集成服务门户(CCPortal): The seesaw response of the intertropical and South Pacific convergence zones to hemispherically asymmetric thermal forcing

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DOI	10.1007/s00382-019-05076-6
	The seesaw response of the intertropical and South Pacific convergence zones to hemispherically asymmetric thermal forcing
	Zhao B.; Fedorov A.
发表日期	2020
ISSN	0930-7575
起始页码	1639
结束页码	1653
卷号	54
英文摘要	Arguments based on atmospheric energetics and aqua-planet model simulations link the latitudinal position of the intertropical convergence zone (ITCZ) to atmospheric cross-equatorial energy transport—a greater southward transport corresponds to a more northerly position of the ITCZ. This idea is often invoked to explain an interhemispheric dipole pattern of precipitation anomalies in paleoclimates. In contrast, here we demonstrate that in the tropical Pacific the response of the fully coupled ocean-atmosphere system to a hemispherically asymmetric thermal forcing, modulating this energy transport, involves an interplay between the ITCZ and its counterpart in the South Pacific—the Southern Pacific convergence zone (SPCZ). This interplay leads to interhemispheric seesaw changes in tropical precipitation, such that the latitudinal position of each rain band remains largely fixed, but their intensities follow a robust inverse relationship. The seesaw behavior is also evident in the past and future coupled climate simulations of the Climate Model Intercomparison Project Phase 5 (CMIP5). We also show that the tropical Pacific precipitation response to thermal forcing is qualitatively different between the aqua-planet (without ocean heat transport), slab-ocean (with climatological ocean heat transport represented by a “Q-flux”) and fully-coupled model configurations. Specifically, the induced changes in the ITCZ latitudinal position successively decrease, while the seesaw precipitation intensity response becomes more prominent, from the aqua-planet to the slab-ocean to the fully-coupled configuration. Thus, the ITCZ/SPCZ seesaw can explain the paleoclimate precipitation dipole pattern without invoking a too strong climate forcing and is relevant to future projections of tropical precipitation. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Climate change; Hemispherically asymmetric thermal forcing; Intertropical convergence zone; Southern Pacific convergence zone
语种	英语
scopus关键词	atmosphere-ocean coupling; climate change; climate forcing; climate modeling; computer simulation; future prospect; intertropical convergence zone; paleoclimate; precipitation (climatology); rainband; temperature effect; Pacific Ocean; Pacific Ocean (South); Pacific Ocean (Tropical)
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/145632
作者单位	Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT 06511, United States; LOCEAN/IPSL, Sorbonne University, 4 Place Jussieu, Paris, France
推荐引用方式 GB/T 7714	Zhao B.,Fedorov A.. The seesaw response of the intertropical and South Pacific convergence zones to hemispherically asymmetric thermal forcing[J],2020,54.
APA	Zhao B.,&Fedorov A..(2020).The seesaw response of the intertropical and South Pacific convergence zones to hemispherically asymmetric thermal forcing.Climate Dynamics,54.
MLA	Zhao B.,et al."The seesaw response of the intertropical and South Pacific convergence zones to hemispherically asymmetric thermal forcing".Climate Dynamics 54(2020).