Timing of MIS 5e marine optimum and implications for the stratigraphic context of last interglacial sediments in the (sub)arctic North Atlantic

• Main Authors: Van Nieuwenhove, Nicolas, Bauch, Henning A., Kandiano, Evgeniya, Matthiessen, Jens, De Vernal, Anne, Fréchette, Bianca
• Format: Conference Object
• Language: unknown
• Published: GEOTOP, Université du Québec 2011
• Subjects: Arctic; Weaver; Foraminifera*; Labrador Sea; Nordic Seas; North Atlantic
• Online Access: https://oceanrep.geomar.de/id/eprint/12157/; http://www.arcticworkshop2011.uqam.ca/upload/files/41aw_abstact_volume.pdf

Marine sediment records of dinoflagellate cyst, foraminiferal and ice rafted debris content and stable isotopes from the Nordic seas and Labrador Sea were used to reconstruct the evolution of the surface circulation in the (sub)arctic North Atlantic during the Last Interglacial. Average global temperatures of this time interval, known as Marine Isotope subStage (MIS) 5e, are believed to have been higher than those of the present Holocene interglacial period. However, the abundance peak of warm dinoflagellate cyst taxa and subpolar planktic foraminifera in the eastern Nordic seas during late MIS 5e would suggest that the development of upper ocean interglacial conditions in that area was delayed with respect to the temperate latitudes, and the marine optimum in the eastern Nordic seas with a surface circulation comparable to the modern one was not reached until late MIS 5e. While the lack of a modern type of surface circulation during much of the early MIS 5e probably prevented the formation of Labrador Sea Water (Hillaire-Marcel et al., 2001), our data furthermore suggest that only with the establishment of this intensified modern-type of northward heat transport, an interglacial surface ocean environment also developed in the northern Nordic seas. Hence, our findings illustrate the importance of a correct (stratigraphic) context placement of those last interglacial records from the high Arctic pointing out overall warmer conditions with respect to the Holocene, as these might represent only specific phases of MIS 5e. Hillaire-Marcel, C., de Vernal, A., Bilodeau, G., Weaver, A.J., 2001. Absence of deep-water formation in the Labrador Sea during the last interglacial period. Nature 410, 1073-1077.