One-to-one coupling of glacial climate variability in Greenland and Antarctica

Nature, Vol. 444, doi:10.1038/nature05301, 2006

EPICA community members:
C. Barbante, V. Gaspari
Department of Environmental Sciences, University Ca' Foscari of Venice, Italy.
P. Gabrielli
Institute for the Dynamics of Environmental Processes-CNR, Dorsoduro 2137, 30123 Venice, Italy.
J.-M. Barnola, C. Boutron, J. Chappellaz, M. Debret, L. Loulergue, F. Parrenin, J.-R. Petit, D. Raynaud
Laboratoire de Glaciologie et Géophysique de l'Environnement (LGGE), CNRS-UJF, BP96 38402 Saint-Martin-d'Hères cedex, France.
S. Becagli, E. Castellano, M. Severi, R. Traversi, R. Udisti
Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
J. Beer
EAWAG, PO Box 611, 8600 Du¨bendorf, Switzerland.
M. Bigler, T. Blunier, U. Federer, M.A. Hutterli, P. Kaufmann, F. Lambert, M. Leuenberger, D. Lüthi, J. Schwander, U. Siegenthaler, R. Spahni, T.F. Stocker, K. Weiler
Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
D. Dahl-Jensen, S. Johnsen, M.-L. Siggaard-Andersen, J.P. Steffensen
Ice and Climate, The Niels Bohr Institute, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark
O. Cattani, S. Falourd, G. Hoffmann, J. Jouzel, A. Landais, V. Masson-Delmotte
Laboratoire des Sciences du Climat et de l'Environnement (LSCE/IPSL), CEA-CNRS-UVSQ, CE Saclay 91191, Gif sur Yvette, France.
B. Delmonte, V. Maggi, F. Marino
Environmental Sciences Department, University of Milano Bicocca, Piazza della Scienza 1, 20126 Milano, Italy.
D. Dick, S. Faria, H. Fischer, J. Freitag, A. Frenzel, F. Fundel, R. Gersonde, I Hamann, P. Huybrechts, S. Kipfstuhl, M. Kohno, Anja Lambrecht, Astrid Lambrecht, G. Lawer, H. Miller, H. Oerter, U. Ruth, O. Rybak, J. Schmitt, F. Valero-Delgado, A. Wegner, F. Wilhelms
Alfred-Wegener-Institute for Polar and Marine Research, Columbusstrasse, D-27568 Bremerhaven, Germany.
D. Fritzsche, H. Meyer
Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam, Telegrafenberg A43, 14473 Potsdam, Germany.
W. Graf
GSF National Center for Environment and Health, Ingolsta¨dter Landstrasse 1, 85764 Neuherberg, Germany.
D. Grigoriev
University College London, Gower Street, London WC1E 6BT, UK.
M. Hansson, T. Karlin
Department of Physical Geography and Quaternary Geology, Stockholm University, 106 91 Stockholm, Sweden.
G. Littot, R. Mulvaney, R. Röthlisberger, E. Wolff
British Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK.
E. Isaksson, M. Kaczmarska, J.-G. Winther
Norwegian Polar Institute, 9296 Tromsø, Norway.
B. Narcisi
ENEA, C. R. Casaccia, Via Anguillarese 301, 00060 Roma, Italy.
J. Oerlemans, M.R. van den Broeke, R.S.W. van de Wal
Utrecht University, Institute for Marine and Atmospheric Research, PO Box 80005, 3508 TA Utrecht, The Netherlands.
G. Raisbeck
CSNSM/IN2P3/CNRS, Bat. 108, 91405 Orsay, France.
B. Stenni
Department of Geological, Environmental and Marine Sciences, University of Trieste, Via E. Weiss 2, 34127 Trieste, Italy.
J.-L. Tison
Département des Sciences de la Terre, Université Libre de Bruxelles, CP160/03, 1050 Brussels, Belgium.
D. Wagenbach
Institute for Environmental Physics, University of Heidelberg, INF229, 69120 Heidelberg, Germany.

Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard-Oeschger events in Greenland through the Atlantic meridional overturning circulation. It has been unclear, however, whether the shorter Dansgaard-Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard-Oeschger events by the bipolar seesaw. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.