气候变化领域集成服务门户(CCPortal): Frequency of exceptional Nile flood events as an indicator of Holocene hydro-climatic changes in the Ethiopian Highlands

CCPortal

DOI	10.1016/j.quascirev.2020.106543
	Frequency of exceptional Nile flood events as an indicator of Holocene hydro-climatic changes in the Ethiopian Highlands
	Mologni C.; Revel M.; Blanchet C.; Bosch D.; Develle A.-L.; Orange F.; Bastian L.; Khalidi L.; Ducassou E.; Migeon S.
发表日期	2020
ISSN	0277-3791
卷号	247
英文摘要	Climate conditions in Africa have varied substantially during the Late Quaternary with alternating humid and arid periods controlled mainly by the African monsoonal regime. However, the duration and termination of the last African Humid Period (14–6 ka BP) and its internal climatic variability are still debated. Using a laminated sequence from the Nile Deep-Sea Fan, we reconstruct for the first time the monsoon-induced frequency of exceptional Nile floods at centennial resolution during the African Humid Period. By combining sedimentological, geochemical and microscopic tools and comparing our record with two proximal piston cores and with regional paleoclimatic records, we show: a) the occurrence of recurrent high-energy floods between 10.1 and 9 ka BP, during the height of the African Humid Period; b) a shift in the hydro-climatic regime as early as 9 ka BP, with a progressive reduction in flood frequency and magnitude until 8.2 ka BP, likely related to a southward migration of the monsoon rainfall belt; c) a drastic reduction of flood activity between 8.2 and 7.8 ka BP; d) an unstable Ethiopian-Nile hydrological system from 7.8 ka BP, followed by a further decrease in river runoff until ∼4 ka BP. The occurrence of a stepwise hydro-climatic deterioration over the Ethiopian Highlands from ∼9 ka BP brings into question the climatic linkages and feedbacks between low and high latitudes during the Early to Mid-Holocene and in particular around the 8.2 ka BP North Atlantic cooling event. Our unique record of flood frequency at centennial-resolution therefore allows us to draw new insights on fluvial and geomorphic feedbacks of the Nile hydrologic system to monsoonal regimes during a period of major environmental shifts. © 2020 Elsevier Ltd
英文关键词	8.2 ka BP event; African Humid Period; African monsoon; Centennial resolution; Hyperpycnal flows; Nile deep-sea fan; Nile flood frequency
语种	英语
scopus关键词	Atmospheric thermodynamics; Deterioration; Climate condition; Climatic variability; Environmental shifts; Hydrologic systems; Hydrological system; Microscopic tools; Nile deep sea fans; Paleoclimatic record; Floods; climate conditions; climate variation; flood; flood frequency; Holocene; hydrometeorology; monsoon; paleoclimate; Quaternary; rainfall; runoff; Ethiopian Highlands; Nile River; Gorgonacea
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151311
作者单位	Université Côte d'Azur, CNRS, Observatoire de la Côte d'Azur, IRD, Géoazur, Sophia Antipolis06905, France; GFZ Potsdam, Department of Climate and Landscape Dynamics, Telegrafenberg, Potsdam, 14743, Germany; Géosciences Montpellier, CNRS UMR-5243, Université Montpellier II, Montpellier, 34095, France; Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, EDYTEM, Chambéry, 73000, France; Université Côte d'Azur, CCMA, Nice, 06100, France; Université Côte d'Azur, CNRS, CEPAM – UMR 7264, Nice, 06300, France; CNRS UMR-5805 EPOC – OASU, Université de Bordeaux, Site de Talence - Bâtiment B18N, Pessac, 33615, France; Sorbonne Université, UFR939, Faculté des Sciences et Ingenierie, Paris, France
推荐引用方式 GB/T 7714	Mologni C.,Revel M.,Blanchet C.,et al. Frequency of exceptional Nile flood events as an indicator of Holocene hydro-climatic changes in the Ethiopian Highlands[J],2020,247.
APA	Mologni C..,Revel M..,Blanchet C..,Bosch D..,Develle A.-L..,...&Migeon S..(2020).Frequency of exceptional Nile flood events as an indicator of Holocene hydro-climatic changes in the Ethiopian Highlands.Quaternary Science Reviews,247.
MLA	Mologni C.,et al."Frequency of exceptional Nile flood events as an indicator of Holocene hydro-climatic changes in the Ethiopian Highlands".Quaternary Science Reviews 247(2020).