EPICA Dome C record of glacial and interglacial intensities

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Abstract

Climate models show strong links between Antarctic and global temperature both in future and in glacial climate simulations. Past Antarctic temperatures can be estimated from measurements of water stable isotopes along the EPICA Dome C ice core over the past 800 000 years. Here we focus on the reliability of the relative intensities of glacial and interglacial periods derived from the stable isotope profile. The consistency between stable isotope-derived temperature and other environmental and climatic proxies measured along the EDC ice core is analysed at the orbital scale and compared with estimates of global ice volume. MIS 2, 12 and 16 appear as the strongest glacial maxima, while MIS 5.5 and 11 appear as the warmest interglacial maxima.

The links between EDC temperature, global temperature, local and global radiative forcings are analysed. We show: (i) a strong but changing link between EDC temperature and greenhouse gas global radiative forcing in the first and second part of the record; (ii) a large residual signature of obliquity in EDC temperature with a 5 ky lag; (iii) the exceptional character of temperature variations within interglacial periods.

Focusing on MIS 5.5, the warmest interglacial of EDC record, we show that orbitally forced coupled climate models only simulate a precession-induced shift of the Antarctic seasonal cycle of temperature. While they do capture annually persistent Greenland warmth, models fail to capture the warming indicated by Antarctic ice core δD. We suggest that the model-data mismatch may result from the lack of feedbacks between ice sheets and climate including both local Antarctic effects due to changes in ice sheet topography and global effects due to meltwater–thermohaline circulation interplays. An MIS 5.5 sensitivity study conducted with interactive Greenland melt indeed induces a slight Antarctic warming. We suggest that interglacial EDC optima are caused by transient heat transport redistribution comparable with glacial north–south seesaw abrupt climatic changes.

Introduction

Glacial–interglacial climate change is expected to result from the orbital forcing, changes in atmospheric composition and internal feedbacks, such as changes in planetary albedo (Paillard, 1998). Along the last million years, changes in land–sea geographical distribution can be considered as negligible in driving past changes in climate and atmospheric composition, in contrast with deeper times. Over this time period, the orbital forcing is well known from astronomical calculations (Berger and Loutre, 1991, Laskar et al., 1993). It is therefore critical to document the relative intensities of past glacial and interglacial periods, in terms of changes in atmospheric composition and global temperatures. Each climate archive provides a complementary view of the global climate system. Globally relevant climate data can be extracted from marine records, where proxies document past changes in tropical sea surface temperature (Lea, 2004), deep ocean temperature (Zachos et al., 2001), or past changes in sea level (Bintanja et al., 2005, Lisiecki and Raymo, 2005), or from continental records documenting past changes in vegetation cover (Cheddadi et al., 2005, Tzedakis et al., 2006) or monsoon intensity (Sun et al., 2006, Wang et al., 2008).

There are specific areas, such as the tropics or Antarctica (Fig. 1), where climate models show a strong link between local temperature changes and global temperature changes (Lea, 2004, Masson-Delmotte et al., 2006a, Schneider von Deimling et al., 2006, Hargreaves et al., 2007, IPCC, 2007). Here, we focus on deep Antarctic ice cores. They offer a variety of new climate and environmental records including the documentation of past atmospheric composition over several glacial–interglacial cycles, at Vostok (Petit et al., 1999), Dome Fuji (Watanabe et al., 2003, Kawamura et al., 2007) or EPICA Dome C (Jouzel et al., 2007, Loulergue et al., 2008, Lüthi et al., 2008). Recently, multiple parameters have been measured on the EPICA Dome C (hereafter EDC) ice core spanning the past 800 000 years (Section 2).

These parameters track climate changes from a variety of latitudes. Past temperatures are relevant for central Antarctica. Past changes in sea salt sodium have been suggested to be related to sea ice surface area, modulated by uplift and transport from the sea ice surface towards central Antarctica. Past changes in methane concentrations are relevant for continental wetland temperature and moisture, mainly in the tropics and the Northern Hemisphere. Past changes in carbon dioxide concentration are relevant for changes in terrestrial and marine carbon sources and sinks, and past changes in dust or non-sea-salt calcium are expected to document dust production on southern hemisphere mid-latitude continents and its transport to Antarctica. Recent studies have been conducted on the sequence of events during terminations (Röthlisberger et al., 2008), but this approach remains difficult to extend to the phase relationships between atmospheric composition and climate due to relative dating uncertainties for the gas and the ice records caused by firnification processes (Caillon et al., 2003, Loulergue et al., 2007).

Section 3 is focused on the relative intensity of glacial and interglacial extrema as identified in various ice core proxies. First, we discuss the uncertainties on past Antarctic temperatures which are estimated from measurements of water stable isotopes along the EPICA EDC ice core over the past 800 000 years. We then discuss the consistency between stable isotope-derived temperature and other environmental and climatic proxies measured in the EDC ice core regarding the relative intensity of glacial and interglacial extrema.

Section 4 is dedicated to the links between radiative perturbations and climate and the new results from the EDC ice core. We discuss the weights of orbital frequencies in EDC temperature. We analyse the links between EDC temperature and greenhouse gas radiative forcing. We use climate models to discuss the relationship between Antarctic and global temperature, highlighting the problems of changes in local ice sheet elevation. A reconstruction of past global temperature variations is compared to the simulations of global temperature response to global radiative forcings estimated from past changes in greenhouse gas concentrations and in northern hemisphere glaciation.

As we show that EDC interglacial temperature variations cannot be explained by a simple response to radiative forcing perturbations, we finally focus our discussion (Section 5) on the warmest interglacial period identified in the EDC ice cores (MIS 5.5). We compare the response of climate models forced by changes in orbital configurations with observational constraints from Greenland and Antarctica. We show that MIS 5.5 Antarctic warmth is not captured by the response of ocean and atmosphere dynamics to orbital forcing and that other feedbacks involving the coupling with the cryosphere must be at play.

Section snippets

Data

In this analysis, we use the available datasets measured and previously published, on the EPICA EDC3 age scale (Parrenin et al., 2007a). This age scale is generated by combining an accumulation and an ice flow model optimised using absolute age markers (Parrenin et al., 2007b). For the time period from 300 to 800 kyr (thousands of years before present), the age scale is obtained from a glaciological interpolation of precession age markers identified in EDC δ18O of O2 (Dreyfus et al., 2007). The

EDC temperature reconstructions

Fig. 1 shows different temperature reconstructions based on EDC stable isotope data. The detailed basis of temperature reconstructions using ice core isotopic composition has been previously published (Jouzel et al., 2003, Masson-Delmotte et al., 2006b, Masson-Delmotte et al., 2008). Due to isotopic distillation processes, changes in central Antarctic snow δD are primarily driven by changes in condensation temperature. Past temperature reconstructions rely on the explicit assumptions of a

Links between changes in radiative forcing and climate

In this section, we now discuss the links between EDC temperature and climate forcings using different approaches. At the local scale, radiative forcings involve changes in obliquity (which affects annual mean insolation) (Section 4.1) and greenhouse gas concentrations (which affects the infra-red loss) (Section 4.2.1). We analyse in Section 4.2.2 the links between EDC temperature and local radiative forcings caused by obliquity and greenhouse gas concentrations.

In a second step, we then use

Discussion of Antarctic interglacial optima

We focus here on MIS 5.5, which appears as an exceptional interglacial period in EDC temperature with the highest temperature of the past 800 ka. It is also exceptional with respect to the residual between EDC temperature and the greenhouse gas radiative forcing (Fig. 6b). Here we use climate models to explore climate feedbacks involved in the simulated response to MIS 5.5 orbital forcing and compare the simulated polar responses in the northern and southern hemispheres (Greenland and

Conclusions and perspectives

The EDC ice core offers a wealth of information on past climate glacial–interglacial dynamics. We have discussed the uncertainties linked with the intensity of glacial and interglacial periods as derived from water stable isotope records, and shown limited effects of changes in local elevation. A deeper understanding of the uncertainties linked with changes in moisture origin will soon be provided by the full record of EDC deuterium excess data.

A solid knowledge of past Antarctic temperature

Acknowledgments

We thank J.R. Petit, G. Raisbeck and M. Werner, A. Timmermann and two anonymous reviewers for constructive comments on the manuscript. This work is a contribution to the European Project for Ice Coring in Antarctica (EPICA), a joint European Science Foundation/European Commission scientific programme, funded by the EU (EPICA-MIS) and by national contributions from Belgium, Denmark, France, Germany, Italy, the Netherlands, Norway, Sweden, Switzerland and the United Kingdom. The main logistic

References (96)

  • Y.B. Sun et al.

    Astronomical time scale and palaeoclimatic implication of stacked 3.6-Myr monsoon records from the Chinese Loess Plateau

    Quaternary Science Reviews

    (2006)
  • F. Vimeux et al.

    New insights into Southern Hemisphere temperature changes from Vostok ice cores using deuterium excess correction over the last 420,000 years

    Earth and Planetary Science Letters

    (2002)
  • E.W. Wolff et al.

    Changes in environment over the last 800 000 years from chemical analysis of the EPICA Dome C ice core

    Quaternary Science Reviews

    (2010)
  • J. Ahn et al.

    Atmospheric CO2 and climate on millennial time scales during the Last Glacial Maximum

    Science

    (2008)
  • T.T. Barrows et al.

    Long-term sea surface temperature and climate change in the Australian–New Zealand region

    Paleoceanography

    (2007)
  • R. Bintanja et al.

    North American ice-sheet dynamics and the onset of 100,000-year glacial cycles

    Nature

    (2008)
  • R. Bintanja et al.

    Modelled atmospheric temperatures and global sea levels over the past million years

    Nature

    (2005)
  • P. Braconnot et al.

    Results of PMIP2 coupled simulations of the Mid-Holocene and Last Glacial Maximum. Part 2: feedbacks with emphasis on the location of the ITCZ and mid- and high latitude heat budget

    Climate of the Past

    (2007)
  • P. Braconnot et al.

    Monsoon response to changes in Earth's orbital parameters: comparisons between simulations of the Eemian and of the Holocene

    Climate of the Past

    (2008)
  • N. Caillon et al.

    Timing of atmospheric CO2 and Antarctic temperature changes across termination III

    Science

    (2003)
  • R. Cheddadi et al.

    Similarity of vegetation dynamics during interglacial periods

    Proceedings of the National Academy of Sciences of the United States of America

    (2005)
  • CLIMAP

    Seasonal reconstructions of the Earth's surface at the Last Glacial Maximum

    (1981)
  • W.M. Connolley

    The Antarctic temperature inversion

    International Journal of Climatology

    (1996)
  • M. Crucifix

    Does the Last Glacial Maximum constrain climate sensitivity?

    Geophysical Research Letters

    (2006)
  • G. Dreyfus et al.

    Anomalous flow below 2700 m in the EPICA Dome C ice core detected using δ18O of atmospheric oxygen measurements

    Climate of the Past

    (2007)
  • A.A. Ekaykin

    Meteorological Regime of Central Antarctic and its Role in the Isotopic Composition of Snow Thickness

    (2003)
  • A.A. Ekaykin et al.

    The changes in isotope composition and accumulation of snow at Vostok station, East Antarctica, over the past 200 years

    Annals of Glaciology

    (2004)
  • EPICA-Community-Members

    Eight glacial cycles from an Antarctic ice core

    Nature

    (2004)
  • EPICA-Community-Members

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

    Nature

    (2006)
  • H. Fischer et al.

    Ice core records of atmospheric CO2 around the last three glacial terminations

    Science

    (1999)
  • H. Gallée et al.

    Validation of a limited area model over Dome C, Antarctic Plateau, during winter

    Climate Dynamics

    (2008)
  • C. Genthon et al.

    Vostok ice core: climatic response to CO2 and orbital forcing changes over the last climatic cycle

    Nature

    (1987)
  • A. Govin et al.

    Evidence for northward expansion of Antarctic Bottom water mass in the Southern Ocean during the last glacial inception

    Paleoceanography

    (2009)
  • M. Gröger et al.

    Changes in the hydrological cycle, ocean circulation and carbon/nutrient cycling during the Last Interglacial and glacial transitions

    Paleoceanography

    (2007)
  • J. Hansen et al.

    Target atmospheric CO2: where should humanity aim?

    Open Atmospheric Sciences

    (2008)
  • J.C. Hargreaves et al.

    Linking glacial and future climates through an ensemble of GCM simulations

    Climate of the Past

    (2007)
  • F. Hourdin et al.

    The LMDZ4 general circulation model: climate performance and sensitivity to parameterizations

    Climate Dynamics

    (2006)
  • P. Huybers et al.

    Antarctic temperature at orbital timescales controlled by local summer duration

    Nature Geosciences

    (2008)
  • IPCC

    Climate Change 2007 – The Physical Science Basis

    (2007)
  • F. Joos

    Radiative forcing and the ice core greenhouse gas record

    PAGES News

    (2005)
  • S. Joussaume et al.

    Status of the Paleoclimate Modeling Intercomparison Project (PMIP)

  • J. Jouzel et al.

    Orbital and millenial Antarctic climate variability over the past 800,000 years

    Science

    (2007)
  • J. Jouzel et al.

    Magnitude of the isotope–temperature scaling for interpretation of central Antarctic ice cores

    Journal of Geophysical Research

    (2003)
  • K. Kawamura et al.

    Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years

    Nature

    (2007)
  • G. Krinner et al.

    GCM analysis of local influences on ice core δ signals

    Geophysical Research Letters

    (1997)
  • C. Kubatzki et al.

    Comparison of the Last Interglacial climate simulated by a coupled global model of intermediate complexity and an AOGCM

    Climate Dynamics

    (2000)
  • F. Lambert et al.

    Dust–climate couplings over the past 800,000 years from the EPICA Dome C ice core

    Nature

    (2008)
  • A. Landais et al.

    A tentative reconstruction of the Greenland Eemian and glacial inception based on gas measurements in the GRIP ice core

    Journal of Geophysical Research

    (2003)
  • Cited by (0)

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