Publikationsdatum:
2022-05-25
Beschreibung:
Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 27 (2012): PA2207, doi:10.1029/2011PA002244.
Beschreibung:
At the peak of the previous interglacial period, North Atlantic and subpolar climate shared many features in common with projections of our future climate, including warmer-than-present conditions and a diminished Greenland Ice Sheet (GIS). Here we portray changes in North Atlantic hydrography linked with Greenland climate during Marine Isotope Stage (MIS) 5e using (sub)centennially sampled records of planktonic foraminiferal isotopes and assemblage counts and ice-rafted debris counts, as well as modern analog technique and Mg/Ca-based paleothermometry. We use the core MD03-2664 recovered from a high accumulation rate site (∼34 cm/kyr) on the Eirik sediment drift (57°26.34′N, 48°36.35′W). The results indicate that surface waters off southern Greenland were ∼3–5°C warmer than today during early MIS 5e. These anomalously warm sea surface temperatures (SSTs) prevailed until the isotopic peak of MIS 5e when they were interrupted by a cooling event beginning at ∼126 kyr BP. This interglacial cooling event is followed by a gradual warming with SSTs subsequently plateauing just below early MIS 5e values. A planktonic δ18O minimum during the cooling event indicates that marked freshening of the surface waters accompanied the cooling. We suggest that switches in the subpolar gyre hydrography occurred during a warmer climate, involving regional changes in freshwater fluxes/balance and East Greenland Current influence in the study area. The nature of these hydrographic transitions suggests that they are most likely related to large-scale circulation dynamics, potentially amplified by GIS meltwater influences.
Beschreibung:
This work is a contribution of the European Science Foundation
EuroMARC program, through the AMOCINT project, funded through
grants from the Research Council of Norway (RCN) and contributes to
EU-FP7 IP Past4Future. N. Irvalı was additionally funded by an ESF
EUROCORES Short-term Visit grant and a RCN Leiv Eiriksson mobility
grant to support research stays at the University of Edinburgh, UK, and
Woods Hole Oceanographic Institution, USA, respectively, during which
parts of the data for this paper were acquired. U. Ninnemann was funded
by a University of Bergen Meltzer research grant.
Beschreibung:
2012-11-12
Schlagwort(e):
Eirik Drift
;
MIS 5e
;
North Atlantic
;
Last interglacial
;
Multiproxy
Repository-Name:
Woods Hole Open Access Server
Materialart:
Article
Format:
application/pdf
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