DOI: 10.1016/j.quascirev.2015.06.026
Scopus记录号: 2-s2.0-84937149668
论文题名: The Plio-Pleistocene development of Atlantic deep-water circulation and its influence on climate trends
作者: Bell D.B. ; Jung S.J.A. ; Kroon D.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2015
卷: 123 起始页码: 265
结束页码: 282
语种: 英语
英文关键词: AMOC
; Paleoceanography
; Pleistocene
; Pliocene
; Stable isotopes
Scopus关键词: Atmospheric temperature
; Feedback
; Glaciers
; Isotopes
; Salinity measurement
; Surface waters
; AMOC
; Paleoceanography
; Pleistocene
; Pliocene
; Stable isotopes
; Oceanography
; abyssal circulation
; climate variation
; deep-sea benthos
; ice sheet
; interglacial
; new record
; Northern Hemisphere
; paleoceanography
; paleoclimate
; Pliocene-Pleistocene boundary
; sea surface temperature
; stable isotope
; surface water
; water flow
; Atlantic Ocean
英文摘要: Using benthic stable isotope records from 10 sites in the Atlantic Ocean, including two new records from Walvis Ridge in the Southeast Atlantic (Sites 1264 and 1267), we review changes in Atlantic deep-water circulation in the context of Plio-Pleistocene climate. Overall, we find non-linear responses of Atlantic deep-water circulation to a cooling climate, with differently evolving glacial and interglacial states. Our main conclusion is that peak North Atlantic Deep Water (NADW) production was reached between ~2.0 and 1.5 Ma, most prominently seen by a maximum in ventilated (high δ13C) conditions in the mid-depth Southeast Atlantic (Site 1264). We infer that a major source of NADW at this time was the export of dense overflow water from the Nordic Seas into the abyssal East Atlantic. Sea surface temperature records from the North and South Atlantic support this notion and indicate that the peak NADW production between ~2.0 and 1.5 Ma was compensated by a stronger warm surface-water return flow (i.e. Atlantic Meridional Overturning Circulation (AMOC) was enhanced), causing long-term (>105 year) heat piracy from the South to the North Atlantic. In the wider picture of Plio-Pleistocene climate evolution, we find that a long-term enhancement in the average state of AMOC (~2.4-1.3 Ma) coincides with the "41-kyr world". Hence, we speculate that the transitory negative feedback response of enhanced AMOC to a cooling climate supplied heat to key areas of ice-sheet growth, acting to limit their size and maintain the "41-kyr world". Once a threshold in global cooling was reached, the strength of AMOC lessened, providing a positive feedback for the Early-Middle Pleistocene Transition and the associated build-up of northern hemisphere ice-sheets. © 2015 The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59857
Appears in Collections: 过去全球变化的重建
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作者单位: School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom
Recommended Citation:
Bell D.B.,Jung S.J.A.,Kroon D.. The Plio-Pleistocene development of Atlantic deep-water circulation and its influence on climate trends[J]. Quaternary Science Reviews,2015-01-01,123