Chapter 10: Global Climate Projections
Executive Summary
Mean Temperature
Temperature Extremes
Mean Precipitation
Precipitation Extremes and Droughts
Snow and Ice
Carbon Cycle
Ocean Acidification
Sea Level
Mean Tropical Pacific Climate Change
El Niño
Monsoons
Sea Level Pressure
Tropical Cyclones (Hurricanes and Typhoons)
Mid-latitude Storms
Atlantic Ocean Meridional Overturning Circulation
Radiative Forcing
Climate Change Commitment (Temperature and Sea Level)
10.1 Introduction
10.2 Projected Changes in Emissions, Concentrations and Radiative Forcing
10.2.1 Emissions Scenarios and Radiative Forcing in the Multi-Model Climate Projections
10.2.2 Recent Developments in Projections of Radiative Species and Forcing for the 21st Century
10.3 Projected Changes in the Physical Climate System
10.3.1 Time-Evolving Global Change
10.3.2 Patterns of Change in the 21st Century
10.3.3 Changes in Ocean/Ice and High-Latitude Climate
10.3.4 Changes in the Atlantic Meridional Overturning Circulation
10.3.5 Changes in Properties of Modes of Variability
FAQ 10.1 Are Extreme Events, Like Heat Waves, Droughts or Floods, Expected to Change as the Earth’s Climate Changes?
10.3.6 Future Changes in Weather and Climate Extremes
10.4 Changes Associated with Biogeochemical Feedbacks and Ocean Acidification
10.4.1 Carbon Cycle/Vegetation Feedbacks
10.4.2 Ocean Acidification Due to Increasing Atmospheric Carbon Dioxide
10.4.3 Simulations of Future Evolution of Methane, Ozone and Oxidants
10.4.4 Simulations of Future Evolution of Major Aerosol Species
10.5 Quantifying the Range of Climate Change Projections
10.5.1 Sources of Uncertainty and Hierarchy of Models
10.5.2 Range of Responses from Different Models
10.5.3 Global Mean Responses from Different Scenarios
10.5.4 Sampling Uncertainty and Estimating Probabilities
10.6 Sea Level Change in the 21st Century
10.6.1 Global Average Sea Level Rise Due to Thermal Expansion
10.6.2 Local Sea Level Change Due to Change in Ocean Density and Dynamics
10.6.3 Glaciers and Ice Caps
10.6.4 Ice Sheets
FAQ 10.2 How Likely are Major or Abrupt Climate Changes, such as Loss of Ice Sheets or Changes in Global Ocean Circulation?
10.6.5 Projections of Global Average Sea Level Change for the 21st Century
10.7 Long Term Climate Change and Commitment
10.7.1 Climate Change Commitment to Year 2300 Based on AOGCMs
FAQ 10.3 If Emissions of Greenhouse Gases are Reduced, How Quickly do Their Concentrations in the Atmosphere Decrease?
10.7.2 Climate Change Commitment to Year 3000 and Beyond to Equilibrium
10.7.3 Long-Term Integrations: Idealised Overshoot Experiments
10.7.4 Commitment to Sea Level Rise
References
Appendix 10.A: Methods for Sea Level Projections for the 21st Century
10.A.1 Scaling MAGICC Results
10.A.2 Mass Balance Sensitivity of Glaciers and Ice Caps
10.A.3 Area Scaling of Glaciers and Ice Caps
10.A.4 Changes in Ice Sheet Surface Mass Balance
10.A.5 Changes in Ice Sheet Dynamics
10.A.6 Combination of Uncertainties
10.A.7 Change in Surface Air Temperature Over the Major West Antarctic Ice Shelves
Coordinating Lead Authors:
Gerald A. Meehl (USA), Thomas F. Stocker (Switzerland)
Lead Authors:
William D. Collins (USA), Pierre Friedlingstein (France, Belgium), Amadou T. Gaye (Senegal), Jonathan M. Gregory (UK),
Akio Kitoh (Japan), Reto Knutti (Switzerland), James M. Murphy (UK), Akira Noda (Japan), Sarah C.B. Raper (UK),
Ian G. Watterson (Australia), Andrew J. Weaver (Canada), Zong-Ci Zhao (China)
Contributing Authors:
R.B. Alley (USA), J. Annan (Japan, UK), J. Arblaster (USA, Australia), C. Bitz (USA), P. Brockmann (France), V. Brovkin (Germany, Russian Federation), L. Buja (USA), P. Cadule (France), G. Clarke (Canada), M. Collier (Australia), M. Collins (UK), E. Driesschaert (Belgium), N.A. Diansky (Russian Federation), M. Dix (Australia), K. Dixon (USA), J.-L. Dufresne (France),
M. Dyurgerov (Sweden, USA), M. Eby (Canada), N.R. Edwards (UK), S. Emori (Japan), P. Forster (UK), R. Furrer (USA, Switzerland),
P. Gleckler (USA), J. Hansen (USA), G. Harris (UK, New Zealand), G.C. Hegerl (USA, Germany), M. Holland (USA), A. Hu (USA, China),
P. Huybrechts (Belgium), C. Jones (UK), F. Joos (Switzerland), J.H. Jungclaus (Germany), J. Kettleborough (UK), M. Kimoto (Japan),
T. Knutson (USA), M. Krynytzky (USA), D. Lawrence (USA), A. Le Brocq (UK), M.-F. Loutre (Belgium), J. Lowe (UK),
H.D. Matthews (Canada), M. Meinshausen (Germany), S.A. Müller (Switzerland), S. Nawrath (Germany), J. Oerlemans (Netherlands), M. Oppenheimer (USA), J. Orr (Monaco, USA), J. Overpeck (USA), T. Palmer (ECMWF, UK), A. Payne (UK), G.-K. Plattner (Switzerland),
J. Räisänen (Finland), A. Rinke (Germany), E. Roeckner (Germany), G.L. Russell (USA), D. Salas y Melia (France), B. Santer (USA),
G. Schmidt (USA, UK), A. Schmittner (USA, Germany), B. Schneider (Germany), A. Shepherd (UK), A. Sokolov (USA, Russian Federation), D. Stainforth (UK), P.A. Stott (UK), R.J. Stouffer (USA), K.E. Taylor (USA), C. Tebaldi (USA), H. Teng (USA, China), L. Terray (France),
R. van de Wal (Netherlands), D. Vaughan (UK), E. M. Volodin (Russian Federation), B. Wang (China), T. M. L. Wigley (USA),
M. Wild (Switzerland), J. Yoshimura (Japan), R. Yu (China), S. Yukimoto (Japan)
Review Editors:
Myles Allen (UK), Govind Ballabh Pant (India)
This chapter should be cited as:
Meehl, G.A., T.F. Stocker, W.D. Collins, P. Friedlingstein, A.T. Gaye, J.M. Gregory, A. Kitoh, R. Knutti, J.M. Murphy, A. Noda, S.C.B. Raper, I.G. Watterson, A.J. Weaver and Z.-C. Zhao, 2007: Global Climate Projections. 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.