skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models

Abstract

For the current generation of earth system models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6), the range of equilibrium climate sensitivity (ECS, a hypothetical value of global warming at equilibrium for a doubling of CO 2) is 1.8°C to 5.6°C, the largest of any generation of models dating to the 1990s. Meanwhile, the range of transient climate response (TCR, the surface temperature warming around the time of CO 2 doubling in a 1% per year CO 2 increase simulation) for the CMIP6 models of 1.7°C (1.3°C to 3.0°C) is only slightly larger than for the CMIP3 and CMIP5 models. Here we review and synthesize the latest developments in ECS and TCR values in CMIP, compile possible reasons for the current values as supplied by the modeling groups, and highlight future directions. Cloud feedbacks and cloud-aerosol interactions are the most likely contributors to the high values and increased range of ECS in CMIP6.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [1]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [7]
  1. National Center for Atmospheric Research, Boulder, CO (United States)
  2. Met Office Hadley Centre, Exeter (United Kingdom)
  3. Deutsches Zentrum für Luft- und Raumfahrt (DLR), Oberpfaffenhofen (Germany); University of Bremen (Germany)
  4. Canadian Centre for Modelling and Analysis, Victoria (Canada)
  5. University of Arizona, Tucson, AZ (United States)
  6. PCMDI, Livermore, CA (United States)
  7. Deutsches Zentrum für Luft- und Raumfahrt (DLR), Oberpfaffenhofen (Germany)
Publication Date:
Research Org.:
University Corporation for Atmospheric Research, Boulder, CO (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
OSTI Identifier:
1670779
Grant/Contract Number:  
89243018SSC000007; AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Science Advances
Additional Journal Information:
Journal Volume: 6; Journal Issue: 26; Journal ID: ISSN 2375-2548
Publisher:
AAAS
Country of Publication:
United States
Language:
English

Citation Formats

Meehl, Gerald A., Senior, Catherine A., Eyring, Veronika, Flato, Gregory, Lamarque, Jean-Francois, Stouffer, Ronald J., Taylor, Karl E., and Schlund, Manuel. Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models. United States: N. p., 2020. Web. doi:10.1126/sciadv.aba1981.
Meehl, Gerald A., Senior, Catherine A., Eyring, Veronika, Flato, Gregory, Lamarque, Jean-Francois, Stouffer, Ronald J., Taylor, Karl E., & Schlund, Manuel. Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models. United States. doi:10.1126/sciadv.aba1981.
Meehl, Gerald A., Senior, Catherine A., Eyring, Veronika, Flato, Gregory, Lamarque, Jean-Francois, Stouffer, Ronald J., Taylor, Karl E., and Schlund, Manuel. Wed . "Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models". United States. doi:10.1126/sciadv.aba1981. https://www.osti.gov/servlets/purl/1670779.
@article{osti_1670779,
title = {Context for interpreting equilibrium climate sensitivity and transient climate response from the CMIP6 Earth system models},
author = {Meehl, Gerald A. and Senior, Catherine A. and Eyring, Veronika and Flato, Gregory and Lamarque, Jean-Francois and Stouffer, Ronald J. and Taylor, Karl E. and Schlund, Manuel},
abstractNote = {For the current generation of earth system models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6), the range of equilibrium climate sensitivity (ECS, a hypothetical value of global warming at equilibrium for a doubling of CO2) is 1.8°C to 5.6°C, the largest of any generation of models dating to the 1990s. Meanwhile, the range of transient climate response (TCR, the surface temperature warming around the time of CO2 doubling in a 1% per year CO2 increase simulation) for the CMIP6 models of 1.7°C (1.3°C to 3.0°C) is only slightly larger than for the CMIP3 and CMIP5 models. Here we review and synthesize the latest developments in ECS and TCR values in CMIP, compile possible reasons for the current values as supplied by the modeling groups, and highlight future directions. Cloud feedbacks and cloud-aerosol interactions are the most likely contributors to the high values and increased range of ECS in CMIP6.},
doi = {10.1126/sciadv.aba1981},
journal = {Science Advances},
issn = {2375-2548},
number = 26,
volume = 6,
place = {United States},
year = {2020},
month = {6}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share:

Works referenced in this record:

Interpretation of Cloud-Climate Feedback as Produced by 14 Atmospheric General Circulation Models
journal, August 1989


Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design and organization
journal, January 2016

  • Eyring, Veronika; Bony, Sandrine; Meehl, Gerald A.
  • Geoscientific Model Development, Vol. 9, Issue 5
  • DOI: 10.5194/gmd-9-1937-2016

Latest climate models confirm need for urgent mitigation
journal, December 2019

  • Forster, Piers M.; Maycock, Amanda C.; McKenna, Christine M.
  • Nature Climate Change, Vol. 10, Issue 1
  • DOI: 10.1038/s41558-019-0660-0

Sensitivity of a global climate model to an increase of CO 2 concentration in the atmosphere
journal, January 1980

  • Manabe, Syukuro; Stouffer, Ronald J.
  • Journal of Geophysical Research, Vol. 85, Issue C10
  • DOI: 10.1029/JC085iC10p05529

Equilibrium Climate Sensitivity: Is It Accurate to Use a Slab Ocean Model?
journal, May 2009


Feedbacks, climate sensitivity and the limits of linear models
journal, November 2015

  • Knutti, Reto; Rugenstein, Maria A. A.
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 373, Issue 2054
  • DOI: 10.1098/rsta.2015.0146

Equilibrium Climate Sensitivity Estimated by Equilibrating Climate Models
journal, February 2020

  • Rugenstein, Maria; Bloch‐Johnson, Jonah; Gregory, Jonathan
  • Geophysical Research Letters, Vol. 47, Issue 4
  • DOI: 10.1029/2019GL083898

Variation in climate sensitivity and feedback parameters during the historical period: VARIATION IN CLIMATE SENSITIVITY
journal, April 2016

  • Gregory, J. M.; Andrews, T.
  • Geophysical Research Letters, Vol. 43, Issue 8
  • DOI: 10.1002/2016GL068406

Interhemispheric asymmetry in climate response to a gradual increase of atmospheric CO2
journal, December 1989

  • Stouffer, R. J.; Manabe, S.; Bryan, K.
  • Nature, Vol. 342, Issue 6250
  • DOI: 10.1038/342660a0

Climate sensitivity due to increased CO2: experiments with a coupled atmosphere and ocean general circulation model
journal, June 1989

  • Washington, Warren M.; Meehl, Gerald A.
  • Climate Dynamics, Vol. 4, Issue 1
  • DOI: 10.1007/BF00207397

Intercomparison makes for a better climate model
journal, January 1997

  • Meehl, Gerald A.; Boer, George J.; Covey, Curt
  • Eos, Transactions American Geophysical Union, Vol. 78, Issue 41
  • DOI: 10.1029/97EO00276

Seasonal oceanic heat transports computed from an atmospheric model
journal, August 1985

  • Russell, Gary L.; Miller, James R.; Tsang, Lie-Ching
  • Dynamics of Atmospheres and Oceans, Vol. 9, Issue 3
  • DOI: 10.1016/0377-0265(85)90022-3

A new method for diagnosing radiative forcing and climate sensitivity
journal, January 2004


Earth System Model Evaluation Tool (ESMValTool) v2.0 – technical overview
journal, January 2020

  • Righi, Mattia; Andela, Bouwe; Eyring, Veronika
  • Geoscientific Model Development, Vol. 13, Issue 3
  • DOI: 10.5194/gmd-13-1179-2020

Climate Response Times: Dependence on Climate Sensitivity and Ocean Mixing
journal, August 1985


Transient Temperature Changes Due to Increasing CO 2 Using Simple Models
journal, January 1984


Analytical solution for the effect of increasing CO2 on global mean temperature
journal, June 1985

  • Wigley, T. M. L.; Schlesinger, M. E.
  • Nature, Vol. 315, Issue 6021
  • DOI: 10.1038/315649a0

The Role of Climate Sensitivity and Ocean Heat Uptake on AOGCM Transient Temperature Response
journal, January 2002


Probabilistic climate change projections for CO 2 stabilization profiles
journal, January 2005


Feedback temperature dependence determines the risk of high warming: FEEDBACK TEMPERATURE DEPENDENCE
journal, June 2015

  • Bloch-Johnson, Jonah; Pierrehumbert, Raymond T.; Abbot, Dorian S.
  • Geophysical Research Letters, Vol. 42, Issue 12
  • DOI: 10.1002/2015GL064240

Nonlinear climate sensitivity and its implications for future greenhouse warming
journal, November 2016

  • Friedrich, Tobias; Timmermann, Axel; Tigchelaar, Michelle
  • Science Advances, Vol. 2, Issue 11
  • DOI: 10.1126/sciadv.1501923

Energy budget constraints on climate sensitivity in light of inconstant climate feedbacks
journal, April 2017


The time-dependence of climate sensitivity
journal, September 2000

  • Senior, Catherine A.; Mitchell, John F. B.
  • Geophysical Research Letters, Vol. 27, Issue 17
  • DOI: 10.1029/2000GL011373

Importance of Ocean Heat Uptake Efficacy to Transient Climate Change
journal, May 2010

  • Winton, Michael; Takahashi, Ken; Held, Isaac M.
  • Journal of Climate, Vol. 23, Issue 9
  • DOI: 10.1175/2009JCLI3139.1

Time-Varying Climate Sensitivity from Regional Feedbacks
journal, July 2013


The Dependence of Radiative Forcing and Feedback on Evolving Patterns of Surface Temperature Change in Climate Models
journal, February 2015


The Dependence of Global Cloud and Lapse Rate Feedbacks on the Spatial Structure of Tropical Pacific Warming
journal, January 2018


Equilibrium- and Transient-State Dependencies of Climate Sensitivity: Are They Important for Climate Projections?
journal, January 2020


Twentieth century climate model response and climate sensitivity
journal, January 2007


Evaluating adjusted forcing and model spread for historical and future scenarios in the CMIP5 generation of climate models: FORCING IN CMIP5 CLIMATE MODELS
journal, February 2013

  • Forster, Piers M.; Andrews, Timothy; Good, Peter
  • Journal of Geophysical Research: Atmospheres, Vol. 118, Issue 3
  • DOI: 10.1002/jgrd.50174

Sensitivity of Historical Climate Simulations to Uncertain Aerosol Forcing
journal, June 2020

  • Dittus, Andrea J.; Hawkins, Ed; Wilcox, Laura J.
  • Geophysical Research Letters, Vol. 47, Issue 13
  • DOI: 10.1029/2019GL085806

High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2)
journal, July 2019

  • Gettelman, A.; Hannay, C.; Bacmeister, J. T.
  • Geophysical Research Letters, Vol. 46, Issue 14
  • DOI: 10.1029/2019GL083978

Strong Dependence of Atmospheric Feedbacks on Mixed‐Phase Microphysics and Aerosol‐Cloud Interactions in HadGEM3
journal, June 2019

  • Bodas‐Salcedo, A.; Mulcahy, J. P.; Andrews, T.
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 6
  • DOI: 10.1029/2019MS001688

Causes of Higher Climate Sensitivity in CMIP6 Models
journal, January 2020

  • Zelinka, Mark D.; Myers, Timothy A.; McCoy, Daniel T.
  • Geophysical Research Letters, Vol. 47, Issue 1
  • DOI: 10.1029/2019GL085782

Climate Sensitivity Estimated from Temperature Reconstructions of the Last Glacial Maximum
journal, November 2011


Inference of Climate Sensitivity from Analysis of Earth's Energy Budget
journal, June 2016


Emergent constraints on Earth’s transient and equilibrium response to doubled CO2 from post-1970s global warming
journal, October 2019


How cold was the Last Glacial Maximum?
journal, January 2006

  • Schneider von Deimling, Thomas; Ganopolski, Andrey; Held, Hermann
  • Geophysical Research Letters, Vol. 33, Issue 14
  • DOI: 10.1029/2006GL026484

Beyond equilibrium climate sensitivity
journal, September 2017

  • Knutti, Reto; Rugenstein, Maria A. A.; Hegerl, Gabriele C.
  • Nature Geoscience, Vol. 10, Issue 10
  • DOI: 10.1038/ngeo3017

What Climate Sensitivity Index Is Most Useful for Projections?
journal, February 2018

  • Grose, Michael R.; Gregory, Jonathan; Colman, Robert
  • Geophysical Research Letters, Vol. 45, Issue 3
  • DOI: 10.1002/2017GL075742

Externally Forced and Internally Generated Decadal Climate Variability Associated with the Interdecadal Pacific Oscillation
journal, September 2013


The Impact of Prescribed Ozone in Climate Projections Run With HadGEM3‐GC3.1
journal, November 2019

  • Hardiman, Steven C.; Andrews, Martin B.; Andrews, Timothy
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 11
  • DOI: 10.1029/2019MS001714

Past warming trend constrains future warming in CMIP6 models
journal, March 2020

  • Tokarska, Katarzyna B.; Stolpe, Martin B.; Sippel, Sebastian
  • Science Advances, Vol. 6, Issue 12
  • DOI: 10.1126/sciadv.aaz9549

The DOE E3SM Coupled Model Version 1: Overview and Evaluation at Standard Resolution
journal, July 2019

  • Golaz, Jean‐Christophe; Caldwell, Peter M.; Van Roekel, Luke P.
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 7
  • DOI: 10.1029/2018MS001603

Structure and Performance of GFDL's CM4.0 Climate Model
journal, November 2019

  • Held, I. M.; Guo, H.; Adcroft, A.
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 11
  • DOI: 10.1029/2019MS001829

Climate Sensitivity of GFDL's CM4.0
journal, January 2020

  • Winton, M.; Adcroft, A.; Dunne, J. P.
  • Journal of Advances in Modeling Earth Systems, Vol. 12, Issue 1
  • DOI: 10.1029/2019MS001838

Forcings, Feedbacks, and Climate Sensitivity in HadGEM3‐GC3.1 and UKESM1
journal, December 2019

  • Andrews, Timothy; Andrews, Martin B.; Bodas‐Salcedo, Alejandro
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 12
  • DOI: 10.1029/2019MS001866

UKESM1: Description and Evaluation of the U.K. Earth System Model
journal, December 2019

  • Sellar, Alistair A.; Jones, Colin G.; Mulcahy, Jane P.
  • Journal of Advances in Modeling Earth Systems
  • DOI: 10.1029/2019MS001739

Description and basic evaluation of simulated mean state, internal variability, and climate sensitivity in MIROC6
journal, January 2019

  • Tatebe, Hiroaki; Ogura, Tomoo; Nitta, Tomoko
  • Geoscientific Model Development, Vol. 12, Issue 7
  • DOI: 10.5194/gmd-12-2727-2019

The Meteorological Research Institute Earth System Model Version 2.0, MRI-ESM2.0: Description and Basic Evaluation of the Physical Component
journal, January 2019

  • Yukimoto, Seiji; Kawai, Hideaki; Koshiro, Tsuyoshi
  • Journal of the Meteorological Society of Japan. Ser. II, Vol. 97, Issue 5
  • DOI: 10.2151/jmsj.2019-051

Developments in the MPI‐M Earth System Model version 1.2 (MPI‐ESM1.2) and Its Response to Increasing CO 2
journal, April 2019

  • Mauritsen, Thorsten; Bader, Jürgen; Becker, Tobias
  • Journal of Advances in Modeling Earth Systems, Vol. 11, Issue 4
  • DOI: 10.1029/2018MS001400

The Canadian Earth System Model version 5 (CanESM5.0.3)
journal, January 2019

  • Swart, Neil C.; Cole, Jason N. S.; Kharin, Viatcheslav V.
  • Geoscientific Model Development, Vol. 12, Issue 11
  • DOI: 10.5194/gmd-12-4823-2019