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| Titel |
An ocean–ice coupled response during the last glacial: a view from a marine isotopic stage 3 record south of the Faeroe Shetland Gateway |
| VerfasserIn |
J. Zumaque, F. Eynaud, S. Zaragosi, F. Marret, K. M. Matsuzaki, C. Kissel, D. M. Roche, B. Malaizé, E. Michel, I. Billy, T. Richter, E. Palis |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1814-9324
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| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 8, no. 6 ; Nr. 8, no. 6 (2012-12-07), S.1997-2017 |
| Datensatznummer |
250005982
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| Publikation (Nr.) |
 copernicus.org/cp-8-1997-2012.pdf |
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| Zusammenfassung |
The rapid climatic variability characterising the Marine Isotopic Stage
(MIS) 3 (~60–30 cal ka BP) provides key issues to understand
the atmosphere–ocean–cryosphere dynamics. Here we investigate the response
of sea-surface paleoenvironments to the MIS3 climatic variability through
the study of a high resolution oceanic sedimentological archive (core
MD99-2281, 60°21' N; 09°27' W; 1197 m water depth),
retrieved during the MD114-IMAGES (International Marine Global Change Study)
cruise from the southern part of the Faeroe Bank. This sector was under the
proximal influence of European ice sheets (Fennoscandian Ice Sheet to the
East, British Irish Ice Sheet to the South) during the last glacial and thus
probably responded to the MIS3 pulsed climatic changes.
We conducted a multi-proxy analysis of core MD99-2281, including magnetic
properties, x-ray fluorescence measurements, characterisation of the coarse
(>150 μm) lithic fraction (grain concentration) and the
analysis of selected biogenic proxies (assemblages and stable isotope ratio
of calcareous planktonic foraminifera, dinoflagellate cyst – e.g. dinocyst – assemblages).
Results presented here are focussed on the dinocyst response,
this proxy providing the reconstruction of past sea-surface hydrological
conditions, qualitatively as well as quantitatively (e.g. transfer function
sensu lato). Our study documents a very coherent and sensitive oceanic response to the
MIS3 rapid climatic variability: strong fluctuations, matching those of
stadial/interstadial climatic oscillations as depicted by Greenland ice
cores, are recorded in the MD99-2281 archive. Proxies of terrigeneous and
detritical material suggest increases in continental advection during
Greenland Stadials (including Heinrich events), the latter corresponding
also to southward migrations of polar waters. At the opposite, milder
sea-surface conditions seem to develop during Greenland Interstadials. After
30 ka, reconstructed paleohydrological conditions evidence strong shifts in
SST: this increasing variability seems consistent with the hypothesised
coalescence of the British and Fennoscandian ice sheets at that time, which
could have directly influenced sea-surface environments in the vicinity of
core MD99-2281. |
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