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DOI	10.1016/j.quascirev.2020.106433
	Holocene stable isotope record of insolation and rapid climate change in a stalagmite from the Zagros of Iran
	Andrews J.E.; Carolin S.A.; Peckover E.N.; Marca A.; Al-Omari S.; Rowe P.J.
发表日期	2020
ISSN	0277-3791
卷号	241
英文摘要	We explore Holocene climatic changes recorded by geochemical proxies in a single, well-dated, stalagmite from the northern Zagros Mountains of Iran, a region where stalagmite records have so far only provided short glimpses of Holocene climatic changes. Stalagmite KT-3 from Katalekhor Cave began growing ∼9.5 ka under wet early Holocene conditions coincident with the timing of Sapropel 1. At this time δ18O values were at or below −9.0‰, stalagmite growth diameter was at its maximum, 234U/238U0 activity values were low and trace element contents indicate flushing of the epikarst. Progressive reduction in winter precipitation amount after 7.0 ka, is recorded by increasing δ18O and 234U/238U0 activity values and reduction in trace element contents and growth diameter until ∼2.0 ka. These trends follow the reduction in summer insolation and agree with model-simulated changes in total rainfall and rainwater isotopes. Sub-centennial-scale variability is not a feature of the δ18O or trace element records; this suggests a stable winter recharge regime, a feature that might militate against KT-3 δ18O recording changes in the seasonality of rainfall. KT-3 δ13C compositions are enriched relative to lower altitude stalagmites in the Levant, implying low soil CO2 contribution (thin montane soils). However, a broadly decreasing millennial-scale trend in δ13C suggests that soil carbon contributions increased with time despite the progressive reduction in winter precipitation amount. The δ13C changes probably reflect decreasing summer temperatures and less extreme wintertime coldness, driven by reducing summer- and increasing winter-insolation respectively. These combined effects decreased effective evaporation and improved soil-moisture availability favouring vegetation development during the growth season. The δ13C values also show ∼1.5‰ centennial-scale variability with higher δ13C values between 9.0 and 8.7 ka, 8.3–7.7 ka, 6.5–5.5 ka, 5.4–4.5 ka and ∼4.3–2.0 ka: three of these correspond with Rapid Climate Change (RCC) events based on non-seasalt potassium (K+) in Greenland ice cores. Higher δ13C values indicate poor soil development caused by aridity. The centennial-scale δ13C anomaly (8.3–7.7 ka) is in part overprinted by the ∼160 year-long, 8.2 ka cold/dry event, but culmination ∼7.7 ka corresponds with other records suggesting an intensified Siberian High Pressure system affecting regional climate. The centennial-scale δ13C anomaly between 4.3 and 2.0 ka overlaps the 2.65 to 2.50 ka ‘Assyrian megadrought’ evident in stalagmite stable isotope records in northern Iraq. The KT-3 record is key in better understanding Holocene climate change in the central Zagros region, representative of montane ‘fertile crescent’ environments. © 2020 Elsevier Ltd
英文关键词	Holocene; Iran; Paleoclimatology; Rapid climate change; Stable isotopes; Stalagmite; Trace elements; Zagros
语种	英语
scopus关键词	Incident solar radiation; Isotopes; Rain; Soil moisture; Trace elements; Centennial scale variability; Geochemical proxies; Greenland ice cores; Holocene climate change; Rapid climate change; Soil moisture availability; Trace element content; Winter precipitation; Climate change; cave system; climate variation; geochronology; Holocene; insolation; oxygen isotope; paleoclimate; precipitation quality; proxy climate record; stable isotope; stalagmite; trace element; Arctic; Greenland; Iran; Iraq; Levant; Mediterranean Region; Zagros
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/151407
作者单位	School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom; Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, United Kingdom; Institute of Geology, University of Innsbruck, Innsbruck, 6020, Austria; Praxis, Office #1501, The Oberoi Center, Business Bay, P.O Box 413898, Dubai, United Arab Emirates
推荐引用方式 GB/T 7714	Andrews J.E.,Carolin S.A.,Peckover E.N.,et al. Holocene stable isotope record of insolation and rapid climate change in a stalagmite from the Zagros of Iran[J],2020,241.
APA	Andrews J.E.,Carolin S.A.,Peckover E.N.,Marca A.,Al-Omari S.,&Rowe P.J..(2020).Holocene stable isotope record of insolation and rapid climate change in a stalagmite from the Zagros of Iran.Quaternary Science Reviews,241.
MLA	Andrews J.E.,et al."Holocene stable isotope record of insolation and rapid climate change in a stalagmite from the Zagros of Iran".Quaternary Science Reviews 241(2020).