气候变化领域集成服务门户(CCPortal): Astronomically controlled aridity in the Sahara since at least 11 million years ago

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DOI	10.1038/s41561-022-00990-7
	Astronomically controlled aridity in the Sahara since at least 11 million years ago
	Crocker, Anya J.; Naafs, B. David A.; Westerhold, Thomas; James, Rachael H.; Cooper, Matthew J.; Roehl, Ursula; Pancost, Richard D.; Xuan, Chuang; Osborne, Colin P.; Beerling, David J.; Wilson, Paul A.
发表日期	2022
ISSN	1752-0894
EISSN	1752-0908
起始页码	671
结束页码	+
卷号	15 期号:8 页码:20
英文摘要	Pulses of Saharan dust have been entering the North Atlantic since at least 11 Ma, a result of astronomically paced cycles between arid and humid conditions in northern Africa, according to a terrigenous input record from an ocean core off west Africa. The Sahara is the largest hot desert on Earth. Yet the timing of its inception and its response to climatic forcing is debated, leading to uncertainty over the causes and consequences of regional aridity. Here we present detailed records of terrestrial inputs from Africa to North Atlantic deep-sea sediments, documenting a long and sustained history of astronomically paced oscillations between a humid and arid Sahara from over 11 million years ago. We show that intervals of strong dust emissions from the heart of the continent predate both the intensification of Northern Hemisphere glaciation and the oldest land-based evidence for a Saharan desert by millions of years. We find no simple long-term gradational transition towards an increasingly arid climate state in northern Africa, suggesting that aridity was not the primary driver of gradual Neogene expansion of African savannah C-4 grasslands. Instead, insolation-driven wet-dry shifts in Saharan climate were common over the past 11 Myr, and we identify three distinct stages in the sensitivity of this relationship. Our data provide context for evolutionary outcomes on Africa; for example, we find that astronomically paced arid intervals predate the oldest fossil evidence of hominid bipedalism by at least 4 Myr.
学科领域	Geosciences, Multidisciplinary
语种	英语
WOS研究方向	Geology
WOS记录号	WOS:000829745100001
来源期刊	NATURE GEOSCIENCE
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/272637
作者单位	NERC National Oceanography Centre; University of Southampton; University of Sheffield; University of Bristol; University of Bristol; University of Bremen
推荐引用方式 GB/T 7714	Crocker, Anya J.,Naafs, B. David A.,Westerhold, Thomas,et al. Astronomically controlled aridity in the Sahara since at least 11 million years ago[J],2022,15(8):20.
APA	Crocker, Anya J..,Naafs, B. David A..,Westerhold, Thomas.,James, Rachael H..,Cooper, Matthew J..,...&Wilson, Paul A..(2022).Astronomically controlled aridity in the Sahara since at least 11 million years ago.NATURE GEOSCIENCE,15(8),20.
MLA	Crocker, Anya J.,et al."Astronomically controlled aridity in the Sahara since at least 11 million years ago".NATURE GEOSCIENCE 15.8(2022):20.