Climate of the Past www.clim-past.net 1814-9324 1814-9332 2 2 2006 10.5194/cp-2-145-2006 http://www.clim-past.net/2/145/2006/ http://www.clim-past.net/2/145/2006/cp-2-145-2006.html http://www.clim-past.net/2/145/2006/cp-2-145-2006.pdf 145 165 2006-10-26 Past temperature reconstructions from deep ice cores: relevance for future climate change V. Masson-Delmotte valerie.masson@cea.fr G. Dreyfus P. Braconnot S. Johnsen J. Jouzel M. Kageyama A. Landais M.-F. Loutre J. Nouet F. Parrenin D. Raynaud B. Stenni E. Tuenter Laboratoire des Sciences du Climat et de l'Environnement, IPSL/CEA-CNRS-UVSQ, Bat 701 L'Orme des Merisiers, CEA Saclay, 91 191 Gif-sur-Yvette cédex, France Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark Institute of Earth Sciences, Hebrew University, Givat Ram, Jerusalem, Israel Institut d'Astronomie et de Géophysique Georges Lemaitre, Université Catholique de Louvain, Louvain-la-Neuve, Belgique Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS-UJF, BP 96 38402 Saint Martin d'Heres Cedex, France Department of Geological, Environmental and Marine Sciences, University of Trieste, Trieste, Italy Department of Earth Sciences, University of Utrecht, Utrecht, The Netherlands Ice cores provide unique archives of past climate and environmental changes based only on physical processes. Quantitative temperature reconstructions are essential for the comparison between ice core records and climate models. We give an overview of the methods that have been developed to reconstruct past local temperatures from deep ice cores and highlight several points that are relevant for future climate change. We first analyse the long term fluctuations of temperature as depicted in the long Antarctic record from EPICA Dome C. The long term imprint of obliquity changes in the EPICA Dome C record is highlighted and compared to simulations conducted with the ECBILT-CLIO intermediate complexity climate model. We discuss the comparison between the current interglacial period and the long interglacial corresponding to marine isotopic stage 11, ~400 kyr BP. Previous studies had focused on the role of precession and the thresholds required to induce glacial inceptions. We suggest that, due to the low eccentricity configuration of MIS 11 and the Holocene, the effect of precession on the incoming solar radiation is damped and that changes in obliquity must be taken into account. The EPICA Dome C alignment of terminations I and VI published in 2004 corresponds to a phasing of the obliquity signals. A conjunction of low obliquity and minimum northern hemisphere summer insolation is not found in the next tens of thousand years, supporting the idea of an unusually long interglacial ahead. As a second point relevant for future climate change, we discuss the magnitude and rate of change of past temperatures reconstructed from Greenland (NorthGRIP) and Antarctic (Dome C) ice cores. Past episodes of temperatures above the present-day values by up to 5°C are recorded at both locations during the penultimate interglacial period. The rate of polar warming simulated by coupled climate models forced by a CO2 increase of 1% per year is compared to ice-core-based temperature reconstructions. In Antarctica, the CO2-induced warming lies clearly beyond the natural rhythm of temperature fluctuations. In Greenland, the CO2-induced warming is as fast or faster than the most rapid temperature shifts of the last ice age. The magnitude of polar temperature change in response to a quadrupling of atmospheric CO2 is comparable to the magnitude of the polar temperature change from the Last Glacial Maximum to present-day. When forced by prescribed changes in ice sheet reconstructions and CO2 changes, climate models systematically underestimate the glacial-interglacial polar temperature change. Alley, R. B. and Agustsdottir, A. M.: The 8 k event: cause and consequences of a major Holocene abrupt climate change, Quaternary Sci. Rev., 24, 1123–1149, 2005. Alley, R. B., Clark, P. U., Huybrechts, P., and Jouqhin, I.: Ice sheet and sea-level changes, Science in China, 310, 456–460, 2005. Archer, A. and Ganopolski, A.: A movable trigger: fossil fuel CO2 and the onset of the next glaciation, Geochem. Geophys. Geosyst., 6, Q05003, doi:10.1029/2004GC000891, 2005. Ashknenazy, J. and Tziperman, E.: Are the 41 kyr glacial oscillations a linear response to Milankovitch forcing?, Quarternary Sci. Rev., 23, 1879–1890, 2004. Bender, M., Labeyrie, L. D., Raynaud, D., and Lorius, C.: Isotopic composition of atmospheric O2 in ice linked with deglaciation and global primary productivity, Nature, 318, 349–352, 1985. Berger, A.: Long-term variation of daily insolation and Quaternary climatic changes, J. Atmos. Sci., 35, 2362–2367, 1978. Berger, A. and Loutre, M. F.: Insolation values for the climate of the last 10 million years, Quaternary Sci. Rev., 10, 297–317, 1991. Berger, A. and Loutre, M. F.: An Exceptionally Long Interglacial Ahead?, Science, 297, 1287–1288, 2002. Berger, A., Loutre, M. F., and Crucifix, M.: The Earth's climate in the next hundred thousand years (100 kyr), Surveys in Geophysics, 24, 117–138, 2003. Berger, A., Loutre, M. F., and Mélice, J. L.: Instability of the astronomical periods from 1.5 Myr BP to 0.5 Myr AP, Paleoclimates, 2, 239–-280, 1998. Bintanja, R., Wal, R. v. d., and Oerlemans, J.: Modelled atmospheric temperatures and global sea levels over the past million years, Nature, 437, 125–128, 2005. Blunier, T. and Brook, E.: Timing of millenial-scale climate change in Antarctica and Greenland during the last glacial period, Science, 291, 109–112, 2001. Braconnot, P.: Modeling the last glacial maximum and mid-holocene, Comptes Rendus Geoscience, 336, 711–719, 2004. Caillon, N., Severinghaus, J. P., Barnola, J.-M., Chappellaz, J., Jouzel, J., and Parrenin, F.: Estimation of temperature change and of gas age – ice age difference, 108 Kyr BP, at Vostok, Antarctica, J. Geophys. Res., 106, 31 893–31 901, 2001. Caillon, N., Severinghaus, J. P., Barnola, J. M., Chappellaz, J. C., Jouzel, J., and Parrenin, F.: Estimation of temperature change and of gas age – ice age difference, 108 kyr BP, at Vostok, Antarctica, J. Geophys. Res., 106, 31 893–31 901, 2001. Calov, R. and Ganopolski, A.: Multistability and hysteresis in the climate-cryosphere system under orbital forcing, Geophys. Res. Lett., 32, L21717, doi:10.1029/2005GL024518, 2005. Chiang, J. C. H. and Bitz, C. M.: Influence of high latitude ice cover on the marine Intertropical Convergence Zone, Clim. Dyn., 25, 477–496, 2005. Ciais, P. and Jouzel, J.: Deuterium and Oxygen 18 in precipitation: an Isotopic Model including Mixed Cloud Processes, J. Geophys. Res., 99, 16 793–16 803, 1994. Claussen, M., Mysak, L. A., Weaver, A. J., Crucifix, M., Fichefet, T., Loutre, M. F., Weber, S. L., Alcamo, J., Alexeev, V. A., Berger, A., Calov, R., Ganopolski, A., Goosse, H., Lohmann, G., Lunkeit, F., Mokhov, I. I., Petoukhov, V., Stone, P., and Wang, Z.: Earth system models of intermediate complexity: closing the gap in the spectrum of climate system models, Clim. Dyn., 18, 579–586, 2002. Cuffey, K. M., Alley, R. B., Grootes, P. M., and Anandakrishnan, S.: Towards using borehole temperatures to calibrate an isotopic paleothermometer in central Greenland, Global Planet. Change, 6, 264–268, 1992. Cuffey, K. M. and Clow, G. D.: Temperature, accumulation, and ice sheet elevation in central Greenland through the last deglacial transition, J. Geophys. Res., 102, 26 383–26 396, 1997. Cuffey, K. M. and Marshall, S. J.: Substantial contribution to sea-level rise during the last interglacial from the Greenland ice sheet, Nature, 404, 591–594, 2000. Cuffey, K. M. and Vimeux, F.: Covariation of carbon dioxyde and temperature from the Vostok ice core after deuterium-excess correction, Nature, 421, 523–527, 2001. Dahl-Jensen, D. and Johnsen, S. J.: Paleotemperatures still exist in the Greenland ice sheet, Nature, 320, 250–252, 1986. Dahl-Jensen, D., Mosegaard, K., Gundestrup, N., Clow, G. D., Johnsen, S. J., Hansen, A. W., and Balling, N.: Past temperatures directly from the Greenland ice sheet, Science, 282, 268–271, 1998. Dahl-Jensen, D., Mosegaard, K., Gundestrup, N., Clow, G. D., Johnsen, S. J., Hausen, A. W., and Balling, N.: Past temperatures directly from the Greenland ice sheet, Science, 282, 268–271, 1998. Dansgaard, W.: Stable isotopes in precipitation, Tellus, 16, 436–468, 1964. Davidson, E. A. and Janssens, I. A.: Temperature sensitivity of soil carbon decomposition and feedbacks to climate change, Nature, 440, 165–173, 2006. Delmotte, M.: Enregistrements climatiques à Law-Dome: variabilité pour les périodes récentes et pour la déglaciation, Unpub. Thèse de doctorat de troisième cycle thesis, Université Joseph Fourier 300 p, 1997. Dethloff, K., Rinke, A., Benkel, A., Koltzow, M., Sokolova, E., Saha, S. K., Handorf, D., Dorn, W., Storch, B. R. H. v., Haugen, J. E., Roed, L. P., Roeckner, E., Christensen, J. H., and Stendel, M.: A dynamical link between the Arctic and the global climate system, Geophys. Res. Lett., 33, L03703,doi:10.1029/2005GL025245, 2006. EPICA-community-members: Eight glacial cycles from an Antarctic ice core, Nature, 429, 623–862, 2004. Gallée, H., Vanypersele, J. P., Fichefet, T., Marsiat, I., Tricot, C., and Berger, A.: Simulation of the last glacial cycle by a coupled, sectorially averaged climate-ice sheet model. 2. Response to insolation and CO2 variations, J. Geophys. Res., 97, 15 713–15 740, 1992. Gallimore, R. G. and Kutzbach, J. E.: Snow cover and sea ice sensitivity to generic changes in Earth orbital parameters, J. Geophys. Res., 100, 1103–1120, 1995. Genthon, C., Barnola, J. M., Raynaud, D., Lorius, C., Jouzel, J., Barkov, N. I., Korotkevich, Y. S., and Kotlyakov, V. M.: Vostok ice core: climatic response to CO2 and orbital forcing changes over the last climatic cycle, Nature, 329, 414–418, 1987. Gildor, H. and Tziperman, E.: Sea-ice as the glacial cycles'climate switch: role of seasonal and orbital forcing, Paleoceanography, 15, 605–615, 2000. Goosse, G. and Fichefet, T.: Importance of ice-ocean interactions for the global ocean circulation a model study, J. Geophys. Res., 104, 23 337–23 355, 1999. Grachev, A. M. and Severinghaus, J. P.: Determining the thermal diffusion factor for 40 Ar/36 Ar in air to aid paleoreconstruction of abrupt climate change, J. Phys. Chem., 107, 4636–4642, 2003. Guo, Z. C., Bromwhich, D. H., and Hines, K. M.: Modeled antarctic precipitation. Part II: ENSO modulation over West Antarctica, J. Climate, 17, 448–465, 2004. Harrison, S. P., Braconnot, P., Joussaume, S., Hewitt, C., and Stouffer, R. J.: Comparison of palaeoclimate simulations enhance confidence in models, EOS Transactions, 83, 447–447, 2002. Hays, J. D., Imbrie, J., and Shackelton, N. J.: Variations in the Earth's orbit: pacemarker of the Ice Ages, Science, 194, 1121–1132, 1976. Henderson, G. M. and Slowey, N. C.: Evidence from U-Th dating against Northern Hemisphere forcing of the penultimate deglaciation, Nature, 404, 61–66, 2000. Holland, M. M. and Bitz, C. M.: Polar amplification of climate change in coupled models, Clim. Dyn., 21, 221–232, 2003. Houghton, J. T.: Climate change 2001: the Scientific Basis: Cambridge, Cambridge University Press, 896, 2001. Huber, C., Leuenberger, M., Spahni, R., Flueckiger, J., Schwander, J., Stocker, T. F., Johnsen, S., Landais, A., and Jouzel, J.: Isotope Calibrated Greenland Temperature Record over Marine Isotope Stage 3 and its Relation to CH4, Earth Planet. Sci. Lett., 243, 504–519, doi:10.1026j.epsl.2006.01.002, 2006. Huybers, P.: Early Pleistocene glacial cycles and the integrated summer insolation forcing, Science, 313, 508�-511, 2006. Huybers, P. and Wunsch, C.: Obliquity pacing of the late Pleistocene glacial terminations, Nature, 434, 491–494, 2005. Imbrie, J. and Imbrie, J. Z.: Modelling the climatic response to orbital variations, Science, 207, 943–953, 1980. IPCC: Climate Change 2001: Impacts, Adaptation and Vulnerability – Contribution of Working Group II to the Third Assessment Report of IPCC, Cambridge University Press, UK, 1000 p., 2001. Johnsen, S., Dahl-Jensen, D., Gundestrup, N., Steffenssen, J. P., Clausen, H. B., Miller, H., Masson-Delmotte, V., Sveinbjörnsdottir, A. E., and J., W.: Oxygen isotope and palaeotemperature records from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP, J. Quaternary Sci., 16, 299–307, 2001. Joussaume, S., Jouzel, J., and Sadourny, R.: A general circulation model of water isotope cycles in the atmosphere, Nature, 311, 24–29, 1984. Jouzel, J., Alley, R. B., Cuffey, K. M., Dansgaard, W., Grootes, P., Hoffmann, G., Johnsen, S. J., Koster, R. D., Peel, D., Shuman, C. A., Stievenard, M., Stuiver, M., and White, J.: Validity of the temperature reconstruction from ice cores, J. Geophys. Res., 102, 26 471–26 487, 1997. Jouzel, J. and Merlivat, L.: Deuterium and Oxygen 18 in precipitation: Modelling of the isotopic effects during snow formation: J. Geophys. Res., 89, 11 749–11 757, 1984. Jouzel, J., Vimeux, F., Caillon, N., Delaygue, G., Hoffmann, G., Masson-Delmotte, V., and Parrenin, F.: Magnitude of the Isotope/Temperature scaling for interpretation of central Antarctic ice cores, J. Geophys. Res., 108, 1029–1046, 2003. Kavanaugh, J. L. and Cuffey, K. M.: Space and time variation of d18O and dD in Antarctic precipitation revisited, Gobal Biogeochem. Cycles, 17, 1017, doi:10.1029/2002GB001910, 2003. Khodri, M., Cane, M. A., Kukla, G., Gavin, J., and Braconnot, P.: The impact of precession changes on the Arctic climate during the last interglacial-glacial transition, Earth Planetary Sci. Lett., 236, 285–304, 2005. Khodri, M., Leclainche, Y., Ramstein, G., Braconnot, P., Marti, O., and Cortijo, E.: Simulating the amplification of orbital forcing by ocean feedbacks in the last glaciation, Nature, 410, 570–574, 2001. Khodri, M., Ramstein, G., Noblet-Ducoudré, N. D., and Kageyama, M.: Sensitivity of the nothern extratropics hydrological cycle to the changing insolation forcing at 126 and 115 kyr BP, Clim. Dyn., 21, 273–287, 2003. Kohler, P., Fischer, H., Munhoven, G., and Zeebe, R. E.: Quantitative interpretation of atmospheric carbon records over the last glacial termination, Glob. Biogeochem. Cycles, 19, GB4020, doi:10.1029/2004GB002345, 2005. Krinner, G. and Genthon, C.: Altitude dependence of the ice sheet surface climate, Geophys. Res. Lett., 26, 2227–2230, 1999. Krinner, G., Genthon, C., and Jouzel, J.: GCM analysis of local influences on ice core $\delta $ signals, Geophys. Res. Lett., 24, 2825–2828, 1997. Krinner, G. and Werner, M.: Impact of precipitation seasonality changes on isotopic signals in polar ice cores, Earth Planet. Sci. Lett., 216, 525–538, 2003. Krinner, G., Boucher, O., and Balkanski, Y.: Ice-free glacial northern Asia due to dust deposition on snow, Clim. Dyn., 27, 613–625, 2006. Landais, A., Barnola, J. M., Masson-Delmotte, V., Jouzel, J., Chappellaz, J., Caillon, N., Hubert, C., Leuenberger, M., and Johnsen, S.: A continuous record of temperature evolution over a whole sequence of Dansgaard-Oeschger during Marine Isotopic Stage 4 (76 to 62 kyr BP), Geophys. Res. Lett., 31, L22211, doi:10.1029/2004GL021193, 2004. Landais, A., Caillon, N., Grachev, A., Barnola, J. M., Chappellaz, J., Jouzel, J., Masson-Delmotte, V., and Leuenberger, M.: Quantification of rapid termperature change during DO event 12 and phasing with methane inferred from air isotopic measurements, Earth Planetary Sci. Lett., 225, 221–232, 2004. Landais, A., Caillon, N., Severinghaus, J., Barnola, J. M., Goujon, C., Jouzel, J., and Masson-Delmotte, V.: Isotopic measurements of air trapped in ice to quantify temperature changes, Comptes Rendus Geoscience, 336, 963–970, 2004. Landais, A., Chappellaz, J., Delmotte, M., Jouzel, J., Blunier, T., Bourg, C., Caillon, N., Cherrier, S., Malaizé, B., Masson-Delmotte, V., Raynaud, D., Schwander, J., and Steffensen, J. P.: A tentative reconstruction of the Greenland Eemian and glacial inception based on gas measurements in the GRIP ice core, J. Geophys. Res., 108, D06103, 1–8, 2003. Landais, A., Masson-Delmotte, V., Jouzel, J., Raynaud, D., Johnsen, S., Huber, C., Leuenberger, M., Schwander, J., and Minster, B.: The glacial inception recorded in the NorthGRIP Greenland ice core: information from air isotopic measurements, Clim. Dyn., 26, doi:10.1007/s00382-005-0063-y, 2005. Lang, C., Leuenberger, M., Schwander, J., and Johnsen, J.: 16°C rapid temperature variation in central Greenland 70 000 years ago, Science, 286, 934–937, 1999. Lawrence, K. T., Liu, Z. H., and Herbert, T. D.: Evolution of the eastern tropical Pacific through Plio-Pleistocene glaciation, Science, 312, 79–83, 2006. Lea, D. W.: The 100 000-Yr cycle in tropical SST, greenhouse forcing, and climate sensitivity, J. Clim., 17, 2170–2179, 2004. Lhomme, N.: Modelling water isotopes in polar ice sheets, University of Bristish Columbia and Université Joseph Fourier, 172 p., 2004. Lhomme, N., Clarke, G. K. C., and Ritz, C.: Global budget of water isotopes inferred from polar ice sheets, Geophys. Res. Lett., 32, L20502, doi:10.1029/2005GL023774, 2005. Liesicki, L. E. and Raymo, M. E.: A Pliocene-Pleistocene stack of 57 globally distributed benthic d18O records, Paleoceanography, 20, PA1003, doi:10.1029/2004PA001071, 2005. Liu, H.-S.: Insolation changes caused by the combination of amplitude and frequency modulation of the obliquity, J. Geophys. Res., 104, 25 197–25 206, 1999. Liu, J. P., Curry, J. A., and Hu, Y. Y.: Recent Arctic Sea Ice Variability: Connections to the Arctic Oscillation and the ENSO, Geophys. Res. Lett., 31, L09211, doi:10.1029/2004GL019858, 2004. Lorius, C. and Merlivat, L.: Distribution of mean surface stable isotope values in East Antarctica. Observed changes with depth in a coastal area, in: Isotopes and impurities in snow and ice, edited by: IAHS, Proceedings of the Grenoble Symposium Aug./Sep. 1975, IAHS Publication, Vienna, IAHS, 125–137, 1977. Loutre, M. F. and Berger, A.: Marine isotope stage 11 as an analogue for the present interglacial, Global Planet. Change, 36, 209–217, 2003. Loutre, M. F., Paillard, D., Vimeux, F., and Cortijo, E.: Does mean annual insolation have the potential to change the climate?, Earth Plant. Sci. Lett., 221, 1–14, 2004. Marshall, J., Kuschner, Y., Battisti, D., Chang, P., Czaja, A., Dickson, R., Hurrell, J., McCartney, M., Saravanan, R., and Visbeck, M.: North Atlantic climate variability: phenomena, impacts and mechanisms, Int. J. Climatology, 21, 1863–1898, 2001. Martinerie, P., Lipenkov, V. Y., and Raynaud, D.: Air content paleo record in the Vostok ice core (Antarctica): a mixed record of climatic and glaciological parameters, J. Geophys. Res., 99, 10 565–10 576, 1994. Masson-Delmotte, V., Jouzel, J., Landais, A., Stievenard, M., Johnsen, S. J., White, J. W. C., Sveinbjornsdottir, A., and Fuhrer, K.: Deuterium excess reveals millennial and orbital scale fluctuations of Greenland moisture origin, Science, 309, 118–121, 2005. Masson-Delmotte, V., Kageyama, M., Braconnot, P., Charbit, S., Krinner, G., Ritz, C., Guilyardi, E., Jouzel, J., Abe-Ouchi, A., Crucifix, M., Gladstone, R. M., Hewitt, C. D., Kitoh, A., Legrande, A., Marti, O., Merkel, U., Motoi, T., Ohgaito, R., Otto-Bliesner, B., Peltier, W. R., Ross, I., Valdes, P. J., Vettoretti, G., Weber, S. L., and Wolk, F.: Past and future polar amplification of climate change: climate model intercomparisons and ice-core constraints, Clim. Dyn., 0930-7575, doi:10.1007/s00382-005-0081-9, 2006. Masson-Delmotte, V., Landais, A., Combourieu-Nebout, N., Grafenstein, U. v., Jouzel, J., Caillon, N., Chappellaz, J., Dahl-Jensen, D., Johnsen, S. J., and Stenni, B.: Rapid climate variability during warm and cold periods in polar regions and Europe, C. R. Geosciences, 337, 935–946, 2005. Masson-Delmotte, V., Landais, A., Stievenard, M., Cattani, O., Falourd, S., Jouzel, J., Johnsen, S. J., Dahl-Jensen, D., Sveinsbjornsdottir, A., White, J. W. C., Popp, T., and Fischer, H.: Holocene climatic changes in Greenland: different deuterium excess signals at GRIP and NorthGRIP, J. Geophys. Res., 110, D14102, doi:10.1029/2004JD005575, 2005. Masson-Delmotte, V., Stenni, B., and Jouzel, J.: Common millenial scale variability of Antarctic and southern ocean temperatures during the past 5000 years reconstructed from EPICA Dome C ice core, The Holocene, 14, 145–151, 2004. Masson, V., Vimeux, F., Jouzel, J., Morgan, V., Delmotte, M., Ciais, P., Hammer, C., Johnsen, S., Lipenkov, V. Y., Mosley-Thompson, E., Petit, J.-R., Steig, E., Stievenard, M., and Vaikmae, R.: Holocene climate variability in Antarctica based on 11 ice cores isotopic records, Quaternary Res., 54, 348–358, 2000. Medina-Elizalde, M. and Lea, D. W.: The Mid-Pleistocene transition in the tropical Pacific, Science, 310, 1009–1012, 2005. Mélice, J. L., Coron, A., and Berger, A.: Amplitude and frequency modulations of the Earth's obliquity for the last million years, J. Climate, 14, 1043–1054, 2001. Merlivat, L. and Jouzel, J.: Global climatic interpretation of the Deuterium-Oxygen 18 relationship for precipitation, J. Geophys. Res., 84, 5029–5033, 1979. Milankovitch, M. M.: Canon of insolation and the ice-age problem, 484, 1941. Neumann, T. A., Waddington, E. D., Steig, E. J., and Grootes, P. M.: Non-climate influences on stable isotopes at Taylor Mouth, Antarctica, J. Glaciology, 51, 248–258, 2005. NorthGRIP-community-members: High resolution climate record of the northern hemisphere reaching into last interglacial period, Nature, 431, 147–151, 2004. Opsteegh, J. D., Haarsma, R. J., Selten, F. M., and Kattenberg, A.: ECBILT: a dynamic alternative to mixed boundary conditions in ocean models, Tellus, 50A, 348–367, 1998. Paillard, D.: The timing of Pleistocene glaciation from a simple multiple-state climate model, Nature, 391, 378–381, 1998. Pälike, H. and Shackleton, N. J.: Constraints on astronomical parameters from the geological record for the last 25 Myr, Earth Planet. Sci. Lett., 182, 1–14, 2001. Parrenin, F., Jouzel, J., Waelbroeck, C., Ritz, C., and Barnola, J.-M.: Dating of the Vostok ice core by an inverse method, J. Geophys. Res., 106, 31 837–31 851, 2001. Parrenin, F. and Paillard, D.: Amplitude and phase of glacial cycles from a conceptual model, Earth Planetary Sci. Lett., 214, 243–250, 2004. Parrenin, F., Rémy, F., Ritz, C., Siegert, M. J., and Jouzel, J.: New modellling of the Vostok ice flow line and implication for the glaciological chronology of the Vostok ice core, J. Geophys. Res., 109, D20102, doi:10.1029/2004JD0044561, 2004. Peltier, W. R.: Global glacial isostasy and the surface of the ice-age Earth: the ICE-5G (VM2) model and GRACE, Annu. Revi. Earth Planet. Sci., 32, 111–149, 2004. Pépin, L., Raynaud, D., Barnola, J.-M., and Loutre, M. F.: Hemispheric roles of climate forcings during glacial-interglacial transitions as deduced from the Vostok record and LLN-2D model experiments, J. Geophys. Res., 106, 31 885–31 892, 2001. Petit, J. R., Jouzel, J., Raynaud, D., Barkov, N. I., Barnola, J.-M., Basile, I., Bender, M., Chappellaz, J., Davis, J., Delaygue, G., Delmotte, M., Kotlyakov, V. M., Legrand, M., Lipenkov, V., Lorius, C., Pépin, L., Ritz, C., Saltzman, E., and Stiévenard, M.: Climate and Atmospheric History of the Past 420 000 years from the Vostok Ice Core, Antarctica, Nature, 399, 429–436, 1999. Rasmussen, S. O., Andersen, K. K., Svensson, A. M., Steffensen, J. P., Vinther, B. M., Clausen, H. B., Siggaard-Andersen, M.-L., Johnsen, S. J., Larsen, L. B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M. E., and Ruth, U.: A new Greenland ice core chronology for the last glacial termination, J. Geophys. Res., D06102, doi:10.1029/2005JD006079, 2006. Raymo, M. E. and Nisancioglu, K.: The 41 kyr world: Milankovitch's other unsolved mystery, Paleoceanography, 18, 1011, doi:10.1029/2002PA000791, 2003. Raynaud, D., Barnola, J. M., Souchez, R., Lorrain, R., Petit, J. R., Duval, P., and Lipenkov, V. Y.: Palaeoclimatology – The record for Marine Isotopic Stage 11, Nature, 436, 39–40, 2005. Rial, J. A.: Pacemaking the ice ages by frequency modulation of Earth's orbital eccentricity, Science, 285, 564–567, 1999. Rial, J. A. and Anaclerio, C. A.: Understanding nonlinear responses of the climate system to orbital forcing, Quaternary Sci. Rev., 19, 1709–1722, 2000. Ritz, C., Rommelaere, V., and Dumas, C.: Modeling the evolution of Antarctic ice sheet over the last 420 000 years: implications for altitude changes in the Vostok region, J. Geophys. Res., 106, 31 943–31 964, 2001. Ruddiman, W. F.: Orbital insolation, ice volume and greenhouse gases, Quaternary Sci. Rev., 15–17, 1597–1629, 2003. Ruddiman, W. F. and Raymo, M. E.: A methane-based time scale for Vostok ice, Quarternary Sci. Rev., 22, 141–155, 2003. Ruddiman, W.: Cold climate during the closest stage 11 analog to recent millennia, Quaternary Sci. Rev., 24, 1111–1121, 2005. Schmidt, G. A., Shindell, D. T., and Harder, S.: A note on the relationship between ice core methane concentrations and insolation: Geophys. Res. Lett., 31, L23206, doi:10.1029/2004GL021083, 2004. Severinghaus, J., Sowers, T., Brook, E. J., Alley, R. B., and Bender, M.: Timing of abrupt climate change at the end of the Younger Dryas interval from thermally fractionated gases in polar ice, Nature, 391, 141–146, 1998. Severinghaus, J. P. and Brook, E.: Simultaneous tropical-Arctic abrupt climate change at the end of the last glacial period inferred from trapped air in polar ice, Science, 286, 930–934, 1999. Severinghaus, J. P., Grachev, A., Luz, B., and Caillon, N.: A method for precise measurement of argon 40/36 and krypton/argon ratios in trapped air in polar ice with applications to past firn thickness and abrupt climate change in Greenland and at Siple Dome, Antarctica, Geochim. Cosmochim. Acta, 67, 325–343, 2003. Shackleton, N. J.: The 100 000 year ice-age cycle identified and found to lag temperature, carbon dioxide, and orbital excentricity, Science, 289, 1897–1902, 2000. Siengenthaler, U., Stocker, T. F., Monnin, E., Lüthi, D., Schwander, J., Stauffer, B., Raynaud, D., Barnola, J.-M., Fischer, H., Masson-Delmotte, V., and Jouzel, J.: Stable carbon cycle-climate relationship during the last Pleistocene, Science, 310, 1313–1317, 2005. Solomon, A.: Impact of latent heat release on polar climate, Geophys. Res. Lett., 33, L07716, doi:10.1029/2005GL025607, 2006. Spahni, R., Chappellaz, J., Stocker, T. F., Loulergue, L., Hausammann, G., Kawamura, K., Flückiger, J., Schwander, J., Raynaud, D., Masson-Delmotte, V., and Jouzel, J.: Variations of atmospheric methane and nitrous oxide during the last 650 000 years from Antarctic ice cores, Science, 310, 1317–1321, 2005. Stenni, B., Jouzel, J., Masson-Delmotte, V., Castellanoc, E., Cattani, O., Falourd, S., Johnsen, S. J., Longinelli, A., Röthlisberger, R., Sachsi, J. P., Selmo, E., Souchez, R., Steffensen, J. P., and Udisti, R.: A high resolution site and source late glacial temperature record derived from the EPICA Dome C isotope records (East Antarctica), Earth Planet. Sci. Lett., 217, 183–195, 2003. Stenni, B., Masson, V., Johnsen, S. J., Jouzel, J., Longinelli, A., Monnin, E., Roethlisberger, R., and Selmo, E.: An oceanic cold reversal during the last deglaciation, Science, 293, 2074–2077, 2001. Tuenter, E., Weber, S. L., Hilgen, F. J., and Lourens, L. J.: Sea-ice feedbacks on the climatic response to precession and obliquity forcing: Geophys. Res. Lett., 32, L24704, doi:10.1029/2005GL024122, 2005. Turner, J.: El Nino-southern oscillation and Antarctica, Int. J. Climatology, 24, 1–31, 2004. Vettoretti, G. and Peltier, W. R.: Sensitivity of glacial inception to orbital and greenhouse gas climate forcing, Quaternary Sci. Rev., 23, 499–519, 2004. Vimeux, F., Masson, V., Jouzel, J., Petit, J. R., Steig, E. J., Stievenard, M., Vaikmae, R., and White, J. W. C.: Holocene hydrological cycle changes in the southern hemisphere documented in East Antarctic deuterium excess records, Clim. Dyn., 17, 503–513, 2001. Vimeux, F., Masson, V., Jouzel, J., Stievenard, M., and Petit, J. R.: Glacial-interglacial changes in ocean surface conditions in the Southern Hemisphere, Nature, 398, 410–413, 1999. Vimeux, F., Masson, V., Delaygue, G., Jouzel, J., Petit, J.-R., and Stievenard, M.: A 420 000 year deuterium excess record from East Antarctica: Information on past changes in the origin of precipitation at Vostok, J. Geophys. Res., 106, 31 863–31 873, 2001. Waelbroeck, C., Labeyrie, L., Michel, E., Duplessy, J. C., McManus, J. F., Lambeck, K., Balbon, E., and Labracherie, M.: Sea level and deep water temperature changes derived from bentic foraminifera isotopic records, Quat. Sci. Rev., 21, 295–305, 2002. Watanabe, O., Jouzel., J., Johnsen, S., Parrenin, F., Shoji, H., and Yoshida, N.: Homogeneous climate variability across East Antarctica over the past three glacial cycles, Nature, 422, 509–512, 2003. Werner, M., Heimann, M., and Hoffmann, G.: Isotopic composition and origin of polar precipitation in present and glacial climate simulations, Tellus, 53B, 53–71, 2001. Wolff, E. W., Fischer, H., Fundel, F., et al.: Southern Ocean sea-ice extent, productivity and iron flux over the past eight glacial cycles, Nature, 440, 491–496, 2006. Yiou, P., Vimeux, F., and Jouzel, J.: Deuterium and deuterium-excess variability over the last four climatic cycles, J. Geophys. Res., 106, 31 875–31 883, 2001. Yuan, X. J.: ENSO-related impacts on Antarctic sea-ice: a synthesis of phenomenon and mechanisms, Antarctic Science, 16, 415–425, 2004. Yuan, X. J. and Martinson, D. G.: Antarctic sea ice extent variability and its global connectivity, J. Climate, 13, 1697–1717, 2000.