Abrupt change of Antarctic moisture origin at the end of Termination II

The deuterium excess of polar ice cores documents past changes in evaporation conditions and moisture origin. New data obtained from the European Project for Ice Coring in Antarctica Dome C East Antarctic ice core provide new insights on the sequence of events involved in Termination II, the transition between the penultimate glacial and interglacial periods. This termination is marked by a north–south seesaw behavior, with first a slow methane concentration rise associated with a strong Antarctic temperature warming and a slow deuterium excess rise. This first step is followed by an abrupt north Atlantic warming, an abrupt resumption of the East Asian summer monsoon, a sharp methane rise, and a CO2 overshoot, which coincide within dating uncertainties with the end of Antarctic optimum. Here, we show that this second phase is marked by a very sharp Dome C centennial deuterium excess rise, revealing abrupt reorganization of atmospheric circulation in the southern Indian Ocean sector.

[1]  V. Masson‐Delmotte,et al.  Changes in atmospheric CO2 and its carbon isotopic ratio during the penultimate deglaciation , 2010 .

[2]  Eric Blayo,et al.  Consistent dating for Antarctic and Greenland ice cores , 2010 .

[3]  J. Hansen,et al.  EPICA Dome C record of glacial and interglacial intensities , 2010 .

[4]  R. Röthlisberger,et al.  The deuterium excess records of EPICA Dome C and Dronning Maud Land ice cores (East Antarctica) , 2010 .

[5]  A. Biastoch,et al.  Increase in Agulhas leakage due to poleward shift of Southern Hemisphere westerlies , 2009, Nature.

[6]  I. N. McCave,et al.  Surface and deep-water hydrography on Gardar Drift (Iceland Basin) during the last interglacial period , 2009 .

[7]  W. Broecker,et al.  Ice Age Terminations , 2009, Science.

[8]  Jerry F. McManus,et al.  Glacial‐interglacial circulation changes inferred from 231Pa/230Th sedimentary record in the North Atlantic region , 2009 .

[9]  C. Waelbroeck,et al.  Evidence for northward expansion of Antarctic Bottom Water mass in the Southern Ocean during the last glacial inception , 2009 .

[10]  M. England,et al.  Southern Hemisphere Westerly Wind Control over the Ocean's Thermohaline Circulation , 2009 .

[11]  Jianping Li,et al.  Boreal spring Southern Hemisphere Annular Mode, Indian Ocean sea surface temperature, and East Asian summer monsoon , 2009 .

[12]  Saleem H Ali,et al.  Wind-Driven Upwelling in the Southern Ocean and the Deglacial Rise in Atmospheric CO2 , 2008, Science.

[13]  M. D. Angelis,et al.  The Southern Hemisphere at glacial terminations: insights from the Dome C ice core , 2008 .

[14]  D. Bromwich,et al.  A Review of Antarctic Surface Snow Isotopic Composition : Observations, Atmospheric Circulation, and Isotopic Modeling , 2008 .

[15]  T. Stocker,et al.  Orbital and millennial-scale features of atmospheric CH4 over the past 800,000 years , 2008, Nature.

[16]  Xiaohua Shao,et al.  Millennial- and orbital-scale changes in the East Asian monsoon over the past 224,000 years , 2008, Nature.

[17]  R. Gersonde,et al.  The last five glacial‐interglacial transitions: A high‐resolution 450,000‐year record from the subantarctic Atlantic , 2007 .

[18]  Kenji Kawamura,et al.  Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years , 2007, Nature.

[19]  Kenji Kawamura,et al.  The EDC3 chronology for the EPICA Dome C ice core , 2007 .

[20]  A. Schilt,et al.  Orbital and Millennial Antarctic Climate Variability over the Past 800,000 Years , 2007, Science.

[21]  A. Timmermann,et al.  Modulation of the bipolar seesaw in the Southeast Pacific during Termination 1 , 2007 .

[22]  Timothy T. Barrows,et al.  Long-term sea surface temperature and climate change in the Australian–New Zealand region , 2007 .

[23]  Gavin A. Schmidt,et al.  Water isotope expressions of intrinsic and forced variability in a coupled ocean‐atmosphere model , 2007 .

[24]  P. Clark,et al.  Geochemical proxies of North American freshwater routing during the Younger Dryas cold event , 2007, Proceedings of the National Academy of Sciences.

[25]  Gareth J. Marshall,et al.  Half‐century seasonal relationships between the Southern Annular mode and Antarctic temperatures , 2007 .

[26]  Jerry F. McManus,et al.  Evolution and demise of the Last Interglacial warmth in the subpolar North Atlantic , 2006 .

[27]  M. Siddall,et al.  Sea-level reversal during Termination II , 2006 .

[28]  Epica Community Members.  One-to-one coupling of glacial climate variability in Greenland and Antarctica , 2006, Nature.

[29]  T. Delworth,et al.  Simulated Tropical Response to a Substantial Weakening of the Atlantic Thermohaline Circulation , 2005 .

[30]  R. Schneider,et al.  Vigorous exchange between the Indian and Atlantic oceans at the end of the past five glacial periods , 2004, Nature.

[31]  C. Pujol,et al.  Climatic “pause” during Termination II identified in shallow and intermediate waters off the Iberian margin , 2004 .

[32]  N. Yoshida,et al.  An observation‐based method for reconstructing ocean surface changes using a 340,000‐year deuterium excess record from the Dome Fuji ice core, Antarctica , 2004 .

[33]  G. Knorr,et al.  Southern Ocean origin for the resumption of Atlantic thermohaline circulation during deglaciation , 2003, Nature.

[34]  Laurent Labeyrie,et al.  Changes in North Atlantic deep-water formation associated with the Dansgaard–Oeschger temperature oscillations (60–10 ka) , 2002 .

[35]  R. Röthlisberger,et al.  An Oceanic Cold Reversal During the Last Deglaciation , 2001, Science.

[36]  Didier Paillard,et al.  The timing of the last deglaciation in North Atlantic climate records , 2001, Nature.

[37]  T. Stocker,et al.  Atmospheric CO2 concentrations over the last glacial termination. , 2001, Science.

[38]  J. Jouzel,et al.  Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica , 1999, Nature.

[39]  J. Jouzel,et al.  Glacial–interglacial changes in ocean surface conditions in the Southern Hemisphere , 1999, Nature.