干旱区生态环境知识资源中心(Arid): Green Sahara tipping points in transient climate model simulations of the Holocene

Arid

DOI	10.1088/1748-9326/ac7c2b
	Green Sahara tipping points in transient climate model simulations of the Holocene
	Hoperoft, Peter O.; Valdes, Paul J.
通讯作者	Hoperoft, PO
来源期刊	ENVIRONMENTAL RESEARCH LETTERS
ISSN	1748-9326
出版年	2022
卷号	17 期号:8
英文摘要	The 'Greening' and subsequent desertification of the Sahara during the early to mid-Holocene is a dramatic example of natural climate change. We analyse a suite of simulations with a newly palaeo-conditioned configuration of the HadCM3 coupled model that is able to capture an abrupt desertification of North Africa during this time. We find that this model crosses a threshold of moisture availability for vegetation at around 6000 years before present. The resultant rapid reduction in vegetation cover acts to reduce precipitation through moisture recycling and surface albedo feedbacks. Precursor drying events which are not directly forced also indicate that the model is close to a critical moisture level. Similar precursor-like events appear in a Holocene record from the East of the continent, hinting that the natural system may resemble some of the properties of this model simulation. The overall response is not fundamentally altered by the inclusion of solar irradiance variations or volcanic eruptions. The simulated timing of the abrupt transition is mostly controlled by orbital forcing and local positive feedbacks, but it is also modulated to some extent by the state of the atmosphere and ocean. Comparisons with proxy records across North Africa show good agreement with the model simulations, although the simulations remain overly dry in the East. Overall, a threshold response may present a useful model of the real transition, but more high-resolution palaeoclimate records would help to discriminate among the predictions of climate models.
英文关键词	Green Sahara abrupt climate change Earth system model land-atmosphere coupling general circulation model
类型	Article
语种	英语
开放获取类型	Green Published, gold
收录类别	SCI-E
WOS记录号	WOS:000830788900001
WOS关键词	EARLY-WARNING SIGNALS ; AFRICAN HUMID PERIOD ; ARABIAN PENINSULA ; NORTHERN AFRICA ; ABRUPT CHANGE ; VEGETATION ; MIDHOLOCENE ; MONSOON ; FEEDBACKS ; OCEAN
WOS类目	Environmental Sciences ; Meteorology & Atmospheric Sciences
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/392508
推荐引用方式 GB/T 7714	Hoperoft, Peter O.,Valdes, Paul J.. Green Sahara tipping points in transient climate model simulations of the Holocene[J],2022,17(8).
APA	Hoperoft, Peter O.,&Valdes, Paul J..(2022).Green Sahara tipping points in transient climate model simulations of the Holocene.ENVIRONMENTAL RESEARCH LETTERS,17(8).
MLA	Hoperoft, Peter O.,et al."Green Sahara tipping points in transient climate model simulations of the Holocene".ENVIRONMENTAL RESEARCH LETTERS 17.8(2022).