气候变化领域集成服务门户(CCPortal): African climate response to orbital and glacial forcing in 140;000-y simulation with implications for early modern human environments

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DOI	10.1073/pnas.1917673117
	African climate response to orbital and glacial forcing in 140;000-y simulation with implications for early modern human environments
	Kutzbach J.E.; Guan J.; He F.; Cohen A.S.; Orland I.J.; Chen G.
发表日期	2020
ISSN	0027-8424
起始页码	2255
结束页码	2264
卷号	117 期号:5
英文摘要	A climate/vegetation model simulates episodic wetter and drier periods at the 21,000-y precession period in eastern North Africa, the Arabian Peninsula, and the Levant over the past 140,000 y. Large orbitally forced wet/dry extremes occur during interglacial time, ∼130 to 80 ka, and conditions between these two extremes prevail during glacial time, ∼70 to 15 ka. Orbital precession causes high seasonality in Northern Hemisphere (NH) insolation at ∼125, 105, and 83 ka, with stronger and northward extended summer monsoon rains in North Africa and the Arabian Peninsula and increased winter rains in the Mediterranean Basin. The combined effects of these two seasonally distinct rainfall regimes increase vegetation and narrow the width of the Saharan–Arabian desert and semidesert zones. During the opposite phase of the precession cycle (∼115, 95, and 73 ka), NH seasonality is low, and decreased summer insolation and increased winter insolation cause monsoon and storm track rains to decrease and the width of the desert zone to increase. During glacial time (∼70 to 15 ka), forcing from large ice sheets and lowered greenhouse gas concentrations combine to increase winter Mediterranean storm track precipitation; the southward retreat of the northern limit of summer monsoon rains is relatively small, thereby limiting the expansion of deserts. The lowered greenhouse gas concentrations cause the near-equatorial zone to cool and reduce convection, causing drier climate with reduced forest cover. At most locations and times, the simulations agree with environmental observations. These changing regional patterns of climate/vegetation could have influenced the dispersal of early humans through expansions and contractions of well-watered corridors. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Africa; Climate modeling; Glacial and orbital forcing; Human dispersal; Paleoclimate
语种	英语
scopus关键词	rain; African; Article; climate change; controlled study; desert; environmental factor; glacial period; greenhouse gas; human; ice sheet; monsoon climate; Northern Hemisphere; precipitation; priority journal; process model; seasonal variation; vegetation; Africa; animal; climate; computer simulation; hominid; ice cover; paleontology; plant; season; Africa; Animals; Climate; Climate Change; Computer Simulation; Earth, Planet; Greenhouse Gases; Hominidae; Humans; Ice Cover; Paleontology; Plants; Rain; Seasons
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/161063
作者单位	Kutzbach, J.E., Center for Climatic Research, Nelson Institute for Environmental Science, University of Wisconsin–Madison, Madison, WI 53706, United States; Guan, J., Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, 100871, China; He, F., Center for Climatic Research, Nelson Institute for Environmental Science, University of Wisconsin–Madison, Madison, WI 53706, United States; Cohen, A.S., Department of Geosciences, University of Arizona, Tucson, AZ 85721, United States; Orland, I.J., Department of Geoscience, University of Wisconsin–Madison, Madison, WI 53706, United States, Wisconsin Geological and Natural History Survey, University of Wisconsin–Madison, Madison, WI 53705, United States; Chen, G., Department of Geoscience, University of Wisconsin–Madison, Madison, WI 53706, United States
推荐引用方式 GB/T 7714	Kutzbach J.E.,Guan J.,He F.,et al. African climate response to orbital and glacial forcing in 140;000-y simulation with implications for early modern human environments[J],2020,117(5).
APA	Kutzbach J.E.,Guan J.,He F.,Cohen A.S.,Orland I.J.,&Chen G..(2020).African climate response to orbital and glacial forcing in 140;000-y simulation with implications for early modern human environments.Proceedings of the National Academy of Sciences of the United States of America,117(5).
MLA	Kutzbach J.E.,et al."African climate response to orbital and glacial forcing in 140;000-y simulation with implications for early modern human environments".Proceedings of the National Academy of Sciences of the United States of America 117.5(2020).