Meridional Shifts of the Southern Hemisphere Westerlies During the Early Cenozoic

doi:10.1029/2024GL110182

IOCAS-IR > 海洋环流与波动重点实验室

	Meridional Shifts of the Southern Hemisphere Westerlies During the Early Cenozoic
	Chen, Hongjin 1; Xu, Zhaokai 2,3; Bayon, Germain 4; Fan, Qingchao2 ; von Strandmann, Philip A. E. Pogge 5; Wang, Wei 6; Sun, Tianqi 2; Li, Tiegang7
	2024-07-16
发表期刊	GEOPHYSICAL RESEARCH LETTERS
ISSN	0094-8276
卷号	51 期号:13 页码:12
通讯作者	Xu, Zhaokai([email protected])
摘要	Despite the crucial role of the Southern Hemisphere (SH) westerlies in modulating modern and past climate evolution, little is known about their behavior and possible forcing mechanisms during the early Cenozoic. We probe changes in the hydroclimate of southwest Australia during 62-51 Ma, based on sedimentary proxy records from the International Ocean Discovery Program Site U1514 in the Mentelle Basin. Our results reveal a transition from a less humid climate to wetter conditions at mid-high latitudes starting from the early Eocene, which suggests poleward migration of the SH westerlies. This long-term trend is punctuated by short-lived events of aridification during the Mid-Paleocene Biotic Event and wetter intervals during the Paleocene-Eocene Thermal Maximum, indicating additional short-term meridional shifting of the westerlies. We propose that the evolution of SH westerlies was driven by the equator-to-pole temperature gradient regulated by global warming and ephemeral growth of the Antarctic ice sheet. The Southern Hemisphere (SH) westerlies, which are the dominant atmospheric circulation patterns in the middle latitudes, play a key role in regulating global and regional climate. Currently, the knowledge of past changes in SH westerlies relies mainly on the late Quaternary. Its dynamics over longer timescales, especially under early Cenozoic greenhouse climate states, remain poorly understood. The Mentelle Basin off southwest Australia was located at a more southerly location than at the present day, and was potentially under the influence of SH westerlies. To examine the long-term hydroclimate changes in southwest Australia during the mid-late Paleocene to the early Eocene (62-51 Ma), we measured neodymium and hafnium isotopic compositions of fine-grained detrital sediments from a borehole (IODP Site U1514) drilled in the Mentelle Basin, in addition to clay mineralogy, and elemental abundances. Our results suggest a gradual wetting of southwest Australia since the early Eocene, which we relate to the poleward migration of SH westerlies in response to a reduced latitudinal temperature gradient. An abrupt northward shift of SH westerlies was observed during the short-lived Middle Paleocene Biotic Event (similar to 59 Ma), possibly driven by ephemeral growth of the Antarctica ice sheet. We reconstruct the hydroclimate evolution of southwest Australia during 62-51 Ma The Southern Hemisphere (SH) westerlies remained relatively stable during the mid-late Paleocene and shifted poleward since the early Eocene Processes related to variations of pole-equator temperature gradients drove meridional migration of the SH westerlies
关键词	early Cenozoic IODP expedition 369 Mentelle Basin Southern Hemisphere westerlies chemical weathering
DOI	10.1029/2024GL110182
收录类别	SCI
语种	英语
资助项目	National Key Research and Development Program of China[2022YFF0800503]; National Natural Science Foundation of China (NSFC)[42306089]; Science and Technology Projects in Guangzhou[SL2023A04J01739]; Director General's Scientific Research Fund of Guangzhou Marine Geological Survey, China[2023GMGSJZJJ00010]; French National Research Agency[ANR-20-CE01-0003]
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:001262098000001
出版者	AMER GEOPHYSICAL UNION
WOS关键词	ND ISOTOPIC COMPOSITION ; HOLOCENE CHANGES ; LATE PALEOCENE ; SEA-LEVEL ; EOCENE ; OCEAN ; HF ; RECORD ; TEMPERATURE ; CLIMATE
引用统计
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/186336
专题	海洋环流与波动重点实验室
通讯作者	Xu, Zhaokai
作者单位	1.China Geol Survey, Minist Nat Resources, Key Lab Marine Mineral Resources, Guangzhou Marine Geol Survey, Guangzhou, Peoples R China 2.Chinese Acad Sci, Inst Oceanol, Key Lab Ocean Observat & Forecasting, Key Lab Marine Geol & Environm, Qingdao, Peoples R China 3.Qingdao Marine Sci & Technol Ctr, Lab Marine Geol, Qingdao, Peoples R China 4.Univ Brest, CNRS, Plouzane, France 5.Johannes Gutenberg Univ Mainz, Inst Geosci, Mainz, Germany 6.Tongji Univ, State Key Lab Marine Geol, Shanghai, Peoples R China 7.Minist Nat Resources, Inst Oceanog 1, Key Lab Marine Sedimentol & Metallogeny, Qingdao, Peoples R China
通讯作者单位	中国科学院海洋研究所
推荐引用方式 GB/T 7714	Chen, Hongjin,Xu, Zhaokai,Bayon, Germain,et al. Meridional Shifts of the Southern Hemisphere Westerlies During the Early Cenozoic[J]. GEOPHYSICAL RESEARCH LETTERS,2024,51(13):12.
APA	Chen, Hongjin.,Xu, Zhaokai.,Bayon, Germain.,Fan, Qingchao.,von Strandmann, Philip A. E. Pogge.,...&Li, Tiegang.(2024).Meridional Shifts of the Southern Hemisphere Westerlies During the Early Cenozoic.GEOPHYSICAL RESEARCH LETTERS,51(13),12.
MLA	Chen, Hongjin,et al."Meridional Shifts of the Southern Hemisphere Westerlies During the Early Cenozoic".GEOPHYSICAL RESEARCH LETTERS 51.13(2024):12.