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Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period
E. Capron1, A. Landais1, J. Chappellaz2, A. Schilt3, D. Buiron2, D. Dahl-Jensen4, S. J. Johnsen4, J. Jouzel1, B. Lemieux-Dudon2, L. Loulergue2, M. Leuenberger3, V. Masson-Delmotte1, H. Mayer5, H. Oerter5, and B. Stenni6
1Institut Pierre-Simon Laplace/Laboratoire des Sciences du Climat et de l'Environnement, CEA-UMR INSU/CNRS 8212-UVSQ, 91191 Gif-sur-Yvette, France
2Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS-UJF, 38400 St Martin d'Hères, France
3Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
4Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100, Copenhagen, Denmark
5Alfred Wegener Institute for Polar and Marine Research, P.O. Box 120161, 27515 Bremerhaven, Germany
6University of Trieste, Department of Geological, Environmental and Marine Sciences, Via E. Weiss 2, 34127 Trieste, Italy
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Abstract. Since its discovery in Greenland ice cores, the millennial scale
climatic variability of the last glacial period has been increasingly
documented at all latitudes with studies focusing mainly on Marine
Isotopic Stage 3 (MIS 3; 28–60 thousand of years before present,
hereafter ka) and characterized by short Dansgaard-Oeschger (DO)
events. Recent and new results obtained on the EPICA and NorthGRIP ice
cores now precisely describe the rapid variations of Antarctic and
Greenland temperature during MIS 5 (73.5–123 ka), a time period
corresponding to relatively high sea level. The results display
a succession of long DO events enabling us to highlight
a sub-millennial scale climatic variability depicted by i) short-lived
and abrupt warming events preceding some Greenland InterStadial (GIS)
(precursor-type events) and ii) abrupt warming events at the end of
some GIS (rebound-type events). The occurrence of these secondary
events is suggested to be driven by the Northern Hemisphere summertime
insolation at 65° N together with the internal forcing of ice
sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML)
common timescale over MIS 5, the bipolar sequence of climatic events
can be established at millennial to sub-millennial timescale. This
provides evidence that a linear relationship is not satisfactory in
explaining the link between Antarctic warming amplitudes and the
duration of their concurrent Greenland Stadial (GS) for the entire
glacial period. The conceptual model for a thermal bipolar seesaw
permits a reconstruction of the Antarctic response to the northern
millennial and sub-millennial scale variability over MIS 5. However,
we show that when ice sheets are extensive, Antarctica does not
necessarily warm during the whole GS as the thermal bipolar seesaw
model would predict.
 Notice on Discussion StatusThe requested discussion paper has a corresponding peer-reviewed
final revised paper in the journal Climate of the Past (CP). You are
encouraged to refer to the final revised version. Final Revised Paper (CP) Discussion Paper (PDF, 2702 KB)
Citation: Capron, E., Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl-Jensen, D., Johnsen, S. J., Jouzel, J., Lemieux-Dudon, B., Loulergue, L., Leuenberger, M., Masson-Delmotte, V., Mayer, H., Oerter, H., and Stenni, B.: Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period, Clim. Past Discuss., 6, 135-183, doi:10.5194/cpd-6-135-2010, 2010. Bibtex EndNote Reference Manager XML
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