101. Regional imprints of millennial variability during the MIS 3 period around Antarctica
- Author
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Didier Swingedouw, Matthias Baumgartner, Valérie Masson-Delmotte, Bénédicte Lemieux-Dudon, Amaelle Landais, Adrian Schilt, Mattia Bonazza, Emilie Capron, Barbara Stenni, Mirko Severi, Frédéric Parrenin, Massimo Frezzotti, Roberto Udisti, Masa Kageyama, D. Buiron, Jérôme Chappellaz, Enricomaria Selmo, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Geologiche [Trieste], Università degli studi di Trieste, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), University of Bern, Italian National agency for new technologies, Energy and sustainable economic development [Frascati] (ENEA), Modélisation du climat (CLIM), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], University of Parma = Università degli studi di Parma [Parme, Italie], Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Buiron, D., Stenni, Barbara, J., Chappellaz, A., Landai, M., Baumgartner, Bonazza, Mattia, E., Capron, M., Frezzotti, M., Kageyama, B., Lemieux Dudon, V., Masson Delmotte, F., Parrenin, A., Schilt, E., Selmo, M., Severi, D., Swingedouw, R., Udisti, Stenni, B., Chappellaz, J., Landais, A., Baumgartner, M., Bonazza, M., Capron, E., Frezzotti, M., Kageyama, M., Lemieux-Dudon, B., Masson-Delmotte, V., Parrenin, F., Schilt, A., Selmo, E., Severi, M., Swingedouw, D., Udisti, R., Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Trieste = University of Trieste, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Università degli studi di Parma = University of Parma (UNIPR), and Università degli Studi di Firenze = University of Florence (UniFI)
- Subjects
Archeology ,010504 meteorology & atmospheric sciences ,Paleoclimate ,Global coupled model simulation ,Greenland Ice Sheet ,atmosphere-ocean coupling ,Greenland ,ice cores ,010502 geochemistry & geophysics ,Oceanography ,01 natural sciences ,Arctic ,Ice core ,Millennial-scale variability ,Ice age ,stable isotope ,Cryosphere ,Climate change ,Glacial period ,Dansgaard-Oeschger cycle ,Indian Sector ,Global coupled model ,sodium ,deuterium ,Talos Dome ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,Global and Planetary Change ,geography.geographical_feature_category ,teleconnection ,Last Glacial ,regional climate ,Geology ,Climatology ,warming ,millennial-scale variability ,glacial period ,global coupled model simulations ,overturn ,Paleoclimatology ,freshwater input ,paleoclimate ,Paleoclimates ,Southern Ocean ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,geography ,Ice ,marine isotope stage ,East Antarctica ,Arctic ice pack ,Glacial geology ,climate variation ,Ice-sheet model ,13. Climate action ,paleoceanography ,coastal zone ,meridional circulation ,Antarctica ,Ice sheet ,ice core - Abstract
International audience; The climate of the last glacial Marine Isotopic Stage 3 (MIS3) period is characterized by strong millennial-scale variability with a succession of Dansgaard–Oeschger events first identified in Greenland ice cores and associated with variations of the Atlantic Meridional Overturning Circulation (AMOC). These abrupt events have a smooth and lagged counterpart in water stable isotopes from Antarctic ice cores. In this study we aim at depicting and understanding the circum-Antarctic expression of this millennial-scale variability. To illustrate the mechanisms potentially at work in the response of the southern high latitudes to an abrupt decrease of the AMOC, we first present results from experiments performed with the IPSL-CM4 atmosphere-ocean coupled model under glacial boundary conditions. When the AMOC is perturbed by imposing an additional freshwater flux in the North Atlantic, our model produces the classical bipolar seesaw mechanism generally invoked to explain the warming of the Southern Ocean/Antarctic region. However, this mechanism can be locally offset by faster atmospheric teleconnections originating from the tropics, even though the precise location of this fast response is not coherent among different climate models. Our model results are confronted with a synthesis of Antarctic records of ice core stable isotope and sea-salt sodium, including new data obtained on the TALDICE ice core. The IPSL-CM4 produces a dipole-like pattern around Antarctica, with warming in the Atlantic/Indian sectors contrasting with an unexpected cooling in the East-Pacific sector. The latter signal is not detected in our data synthesis. Both ice core data and simulations are consistent in depicting a more rapid response of the Atlantic sector compared to the Indian sector. This feature can be explained by the gradual impact of ocean transport on which faster atmospheric teleconnections are superimposed. Detailed investigations of the sequence of events between different proxies are conducted in three ice cores. Earlier shifts in deuterium excess and significant changes in sea-salt sodium fluxes in the most coastal sites (TALDICE and EDML) compared to EDC suggest reorganizations in local moisture sources, possibly linked with sea-ice cover. This study demonstrates the added value of circum-Antarctic ice core records to characterize the patterns and mechanisms of glacial climate variability.
- Published
- 2012
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