IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group I: The Physical Science Basis

Chapter 6: Palaeoclimate

Executive Summary

6.1 Introduction

6.2 Palaeoclimatic Methods

6.2.1 Methods – Observations of Forcing and Response

6.2.2 Methods – Palaeoclimate Modelling

6.3 The Pre-Quaternary Climates

6.3.1 What is the Relationship Between Carbon Dioxide and Temperature in this Time Period?

6.3.2 What Does the Record of the Mid-Pliocene Show?

6.3.3 What Does the Record of the Palaeocene-Eocene Thermal Maximum Show?

6.4 Glacial-Interglacial Variability and Dynamics

6.4.1 Climate Forcings and Responses Over Glacial-Interglacial Cycles

FAQ 6.1 What Caused the Ice Ages and Other Important Climate Changes Before the Industrial Era?

6.4.2 Abrupt Climatic Changes in the Glacial-Interglacial Record

6.4.3 Sea Level Variations Over the Last Glacial-Interglacial Cycle

6.5 The Current Interglacial

6.5.1 Climate Forcing and Response During the Current Interglacial

6.5.2 Abrupt Climate Change During the Current Interglacial

FAQ 6.2 Is the Current Climate Change Unusual Compared to Earlier Changes in Earth’s History?

6.5.3 How and Why Has the El Niño-Southern Oscillation Changed Over the Present Interglacial?

6.6 The Last 2,000 Years

6.6.1 Northern Hemisphere Temperature Variability

6.6.2 Southern Hemisphere Temperature Variability

6.6.3 Comparisons of Millennial Simulations with Palaeodata

6.6.4 Consistency Between Temperature, Greenhouse Gas and Forcing Records; and Compatibility of Coupled Carbon Cycle-Climate Models with the Proxy Records

6.6.5 Regional Variability in Quantities Other than Temperature

6.7 Concluding Remarks on Key Uncertainties

References

Coordinating Lead Authors:

Eystein Jansen (Norway), Jonathan Overpeck (USA)

Lead Authors:

Keith R. Briffa (UK), Jean-Claude Duplessy (France), Fortunat Joos (Switzerland), Valérie Masson-Delmotte (France), Daniel Olago (Kenya), Bette Otto-Bliesner (USA), W. Richard Peltier (Canada), Stefan Rahmstorf (Germany), Rengaswamy Ramesh (India), Dominique Raynaud (France), David Rind (USA), Olga Solomina (Russian Federation), Ricardo Villalba (Argentina), De’er Zhang (China)

Contributing Authors:

J.-M. Barnola (France), E. Bauer (Germany), E. Brady (USA), M. Chandler (USA), J. Cole (USA), E. Cook (USA), E. Cortijo (France), T. Dokken (Norway), D. Fleitmann (Switzerland, Germany), M. Kageyama (France), M. Khodri (France), L. Labeyrie (France), A. Laine (France), A. Levermann (Germany), Ø. Lie (Norway), M.-F. Loutre (Belgium), K. Matsumoto (USA), E. Monnin (Switzerland), E. Mosley-Thompson (USA), D. Muhs (USA), R. Muscheler (USA), T. Osborn (UK), Ø. Paasche (Norway), F. Parrenin (France), G.-K. Plattner (Switzerland), H. Pollack (USA), R. Spahni (Switzerland), L.D. Stott (USA), L. Thompson (USA), C. Waelbroeck (France), G. Wiles (USA), J. Zachos (USA), G. Zhengteng (China)

Review Editors:

Jean Jouzel (France), John Mitchell (UK)

This chapter should be cited as:

Jansen, E., J. Overpeck, K.R. Briffa, J.-C. Duplessy, F. Joos, V. Masson-Delmotte, D. Olago, B. Otto-Bliesner, W.R. Peltier, S. Rahmstorf, R. Ramesh, D. Raynaud, D. Rind, O. Solomina, R. Villalba and D. Zhang, 2007: Palaeoclimate. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.