气候变化领域集成服务门户(CCPortal): Modal shift in North Atlantic seasonality during the last deglaciation

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DOI	10.5194/cp-16-265-2020
	Modal shift in North Atlantic seasonality during the last deglaciation
	Brummer G.-J.A.; Metcalfe B.; Feldmeijer W.; Prins M.A.; Van 'T Hoff J.; Ganssen G.M.
发表日期	2020
ISSN	18149324
起始页码	265
结束页码	282
卷号	16 期号:1
英文摘要	Changeover from a glacial to an interglacial climate is considered as transitional between two stable modes. Palaeoceanographic reconstructions using the polar foraminifera Neogloboquadrina pachyderma highlight the retreat of the Polar Front during the last deglaciation in terms of both its decreasing abundance and stable oxygen isotope values (δ18O) in sediment cores. While conventional isotope analysis of pooled N. pachyderma and G. bulloides shells shows a warming trend concurrent with the retreating ice, new single-shell measurements reveal that this trend is composed of two isotopically different populations that are morphologically indistinguishable. Using modern time series as analogues for interpreting downcore data, glacial productivity in the mid-North Atlantic appears limited to a single maximum in late summer, followed by the melting of drifting icebergs and winter sea ice. Despite collapsing ice sheets and global warming during the deglaciation, a second "warm" population of N. pachyderma appears in a bimodal seasonal succession, separated by the subpolar G. bulloides. This represents a shift in the timing of the main plankton bloom from late to early summer in a "deglacial" intermediate mode that persisted from the glacial maximum until the start of the Holocene. When seawater temperatures exceeded the threshold values, first the "cold" (glacial) then the "warm" (deglacial) populations of N. pachyderma disappeared, whilst G. bulloides with a greater tolerance to higher temperatures persisted throughout the Holocene to the present day in the midlatitude North Atlantic. Singlespecimen δ18O of polar N. pachyderma reveals a steeper rate of ocean warming during the last deglaciation than appears from conventional pooled δ18O average values. © 2020 Author(s).
语种	英语
scopus关键词	algal bloom; global warming; Holocene; last glaciation; oxygen isotope; reconstruction; seasonality; time series; Atlantic Ocean; Atlantic Ocean (North); Foraminifera; Neogloboquadrina pachyderma
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146745
作者单位	NIOZ Royal Netherlands Institute for Sea Research, Department of Ocean Systems, Utrecht University, AB, Den Burg, 1790, Netherlands; Earth and Climate Cluster, Department of Earth Sciences, Faculty of Science, VU University Amsterdam, de Boelelaan 1085, HV, Amsterdam, 1081, Netherlands; Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, 91191, France; Nebest B.V., Marconiweg 2, PD, Vianen, 4131, Netherlands; Institute of Geology and Mineralogy, University of Cologne, Zuelpicher Str. 49a, Cologne, 50674, Germany
推荐引用方式 GB/T 7714	Brummer G.-J.A.,Metcalfe B.,Feldmeijer W.,et al. Modal shift in North Atlantic seasonality during the last deglaciation[J],2020,16(1).
APA	Brummer G.-J.A.,Metcalfe B.,Feldmeijer W.,Prins M.A.,Van 'T Hoff J.,&Ganssen G.M..(2020).Modal shift in North Atlantic seasonality during the last deglaciation.Climate of the Past,16(1).
MLA	Brummer G.-J.A.,et al."Modal shift in North Atlantic seasonality during the last deglaciation".Climate of the Past 16.1(2020).