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

Chapter 3: Observations: Surface and Atmospheric Climate Change

Executive Summary

3.1 Introduction

3.2 Changes in Surface Climate: Temperature

3.2.1 Background

3.2.2 Temperature in the Instrumental Record for Land and Oceans

FAQ 3.1 How are Temperatures on Earth Changing?

3.3 Changes in Surface Climate: Precipitation, Drought and Surface Hydrology

3.3.1 Background

3.3.2 Changes in Large-scale Precipitation

3.3.3 Evapotranspiration

3.3.4 Changes in Soil Moisture, Drought, Runoff and River Discharge

FAQ 3.2 How is Precipitation Changing?

3.3.5 Consistency and Relationships between Temperature and Precipitation

3.3.6 Summary

3.4 Changes in the Free Atmosphere

3.4.1 Temperature of the Upper Air: Troposphere and Stratosphere

3.4.2 Water Vapour

3.4.3 Clouds

3.4.4 Radiation

3.5 Changes in Atmospheric Circulation

3.5.1 Surface or Sea Level Pressure

3.5.2 Geopotential Height, Winds and the Jet Stream

3.5.3 Storm Tracks

3.5.4 Blocking

3.5.5 The Stratosphere

3.5.6 Winds, Waves and Surface Fluxes

3.5.7 Summary

3.6 Patterns of Atmospheric Circulation Variability

3.6.1 Teleconnections

3.6.2 El Niño-Southern Oscillation and Tropical/Extratropical Interactions

3.6.3 Pacific Decadal Variability

3.6.4 The North Atlantic Oscillation and Northern Annular Mode

3.6.5 The Southern Hemisphere and Southern Annular Mode

3.6.6 Atlantic Multi-decadal Oscillation

3.6.7 Other Indices

3.6.8 Summary

3.7 Changes in the Tropics and Subtropics, and in the Monsoons

3.7.1 Asia

3.7.2 Australia

3.7.3 The Americas

3.7.4 Africa

3.7.5 Summary

3.8 Changes in Extreme Events

3.8.1 Background

3.8.2 Evidence for Changes in Variability or Extremes

3.8.3 Evidence for Changes in Tropical Storms

FAQ 3.3 Has there been a Change in Extreme Events like Heat Waves, Droughts, Floods and Hurricanes?

3.8.4 Evidence for Changes in Extratropical Storms and Extreme Events

3.8.5 Summary

3.9 Synthesis: Consistency Across Observations


Appendix 3.A: Low-Pass Filters and Linear Trends

Appendix 3.B: Techniques, Error Estimation and Measurement Systems: See Supplementary Material

Coordinating Lead Authors:

Kevin E. Trenberth (USA), Philip D. Jones (UK)

Lead Authors:

Peter Ambenje (Kenya), Roxana Bojariu (Romania), David Easterling (USA), Albert Klein Tank (Netherlands), David Parker (UK), Fatemeh Rahimzadeh (Iran), James A. Renwick (New Zealand), Matilde Rusticucci (Argentina), Brian Soden (USA), Panmao Zhai (China)

Contributing Authors:

R. Adler (USA), L. Alexander (UK, Australia, Ireland), H. Alexandersson (Sweden), R. Allan (UK), M.P. Baldwin (USA), M. Beniston (Switzerland), D. Bromwich (USA), I. Camilloni (Argentina), C. Cassou (France), D.R. Cayan (USA), E.K.M. Chang (USA), J. Christy (USA), A. Dai (USA), C. Deser (USA), N. Dotzek (Germany), J. Fasullo (USA), R. Fogt (USA), C. Folland (UK), P. Forster (UK), M. Free (USA), C. Frei (Switzerland), B. Gleason (USA), J. Grieser (Germany), P. Groisman (USA, Russian Federation), S. Gulev (Russian Federation), J. Hurrell (USA), M. Ishii (Japan), S. Josey (UK), P. Kållberg (ECMWF), J. Kennedy (UK), G. Kiladis (USA), R. Kripalani (India), K. Kunkel (USA), C.-Y. Lam (China), J. Lanzante (USA), J. Lawrimore (USA), D. Levinson (USA), B. Liepert (USA), G. Marshall (UK), C. Mears (USA), P. Mote (USA), H. Nakamura (Japan), N. Nicholls (Australia), J. Norris (USA), T. Oki (Japan), F.R. Robertson (USA), K. Rosenlof (USA), F.H. Semazzi (USA), D. Shea (USA), J.M. Shepherd (USA), T.G. Shepherd (Canada), S. Sherwood (USA), P. Siegmund (Netherlands), I. Simmonds (Australia), A. Simmons (ECMWF, UK), C. Thorncroft (USA, UK), P. Thorne (UK), S. Uppala (ECMWF), R. Vose (USA), B. Wang (USA), S. Warren (USA), R. Washington (UK, South Africa), M. Wheeler (Australia), B. Wielicki (USA), T. Wong (USA), D. Wuertz (USA)

Review Editors:

Brian J. Hoskins (UK), Thomas R. Karl (USA), Bubu Jallow (The Gambia)

This chapter should be cited as:

Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D. Parker, F. Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden and P. Zhai, 2007: Observations: Surface and Atmospheric Climate Change. 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.