Rapid reductions in North Atlantic Deep Water during the peak of the last interglacial period

Deep ocean circulation has been considered relatively stable during interglacial periods, yet little is known about its behavior on submillennial time scales. Using a subcentennially resolved epibenthic foraminiferal d13C record, we show that the influence of North Atlantic Deep Water (NADW) was strong at the onset of the last interglacial period and was then interrupted by several prominent centennial-scale reductions. These NADW transients occurred during periods of increased ice rafting and southward expansions of polar water influence, suggesting that a buoyancy threshold for convective instability was triggered by freshwater and circum-Arctic cryosphere changes. The deep Atlantic chemical changes were similar in magnitude to those associated with glaciations, implying that the canonical view of a relatively stable interglacial circulation may not hold for conditions warmer and fresher than at present.

Disciplines

Marine geology

Keywords

paleoceanography, NADW, AMOC, last interglacial period, MIS 5e, Eem, North Atlantic, Eirik Drift, benthic foraminifera d13C

Location

64.334631N, 49.288525S, -30.146484E, -62.578125W

Data

FileSizeFormatProcessingAccess
Galaasen et al. (2014) supplementary data.
71 KoXLS, XLSXProcessed data
How to cite
Galaasen Eirik Vinje, Ninnemann Ulysses S, Irvali Nil, Kleiven Helga (Kikki) F, Rosenthal Yair, Kissel Catherine, Hodell David A (2014). Rapid reductions in North Atlantic Deep Water during the peak of the last interglacial period. SEANOE. https://doi.org/10.17882/78577

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