High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2)
Abstract
The Community Earth System Model Version 2 (CESM2) has an equilibrium climate sensitivity (ECS) of 5.3 K. ECS is an emergent property of both climate feedbacks and aerosol forcing. The increase in ECS over the previous version (CESM1) is the result of cloud feedbacks. Interim versions of CESM2 had a land model that damped ECS. Part of the ECS change results from evolving the model configuration to reproduce the long-term trend of global and regional surface temperature over the twentieth century in response to climate forcings. Changes made to reduce sensitivity to aerosols also impacted cloud feedbacks, which significantly influence ECS. We report CESM2 simulations compare very well to observations of present climate. It is critical to understand whether the high ECS, outside the best estimate range of 1.5–4.5 K, is plausible.
- Authors:
-
- National Center for Atmospheric Research, Boulder, CO (United States)
- Publication Date:
- Research Org.:
- University Corporation for Atmospheric Research, Boulder, CO (United States)
- Sponsoring Org.:
- National Science Foundation (NSF); USDOE Office of Science (SC), Biological and Environmental Research (BER)
- OSTI Identifier:
- 1609288
- Grant/Contract Number:
- FC02-97ER62402
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Geophysical Research Letters
- Additional Journal Information:
- Journal Volume: 46; Journal Issue: 14; Journal ID: ISSN 0094-8276
- Publisher:
- American Geophysical Union
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 58 GEOSCIENCES; Geology
Citation Formats
Gettelman, A., Hannay, C., Bacmeister, J. T., Neale, R. B., Pendergrass, A. G., Danabasoglu, G., Lamarque, J.‐F., Fasullo, J. T., Bailey, D. A., Lawrence, D. M., and Mills, M. J. High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2). United States: N. p., 2019.
Web. doi:10.1029/2019gl083978.
Gettelman, A., Hannay, C., Bacmeister, J. T., Neale, R. B., Pendergrass, A. G., Danabasoglu, G., Lamarque, J.‐F., Fasullo, J. T., Bailey, D. A., Lawrence, D. M., & Mills, M. J. High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2). United States. https://doi.org/10.1029/2019gl083978
Gettelman, A., Hannay, C., Bacmeister, J. T., Neale, R. B., Pendergrass, A. G., Danabasoglu, G., Lamarque, J.‐F., Fasullo, J. T., Bailey, D. A., Lawrence, D. M., and Mills, M. J. Tue .
"High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2)". United States. https://doi.org/10.1029/2019gl083978. https://www.osti.gov/servlets/purl/1609288.
@article{osti_1609288,
title = {High Climate Sensitivity in the Community Earth System Model Version 2 (CESM2)},
author = {Gettelman, A. and Hannay, C. and Bacmeister, J. T. and Neale, R. B. and Pendergrass, A. G. and Danabasoglu, G. and Lamarque, J.‐F. and Fasullo, J. T. and Bailey, D. A. and Lawrence, D. M. and Mills, M. J.},
abstractNote = {The Community Earth System Model Version 2 (CESM2) has an equilibrium climate sensitivity (ECS) of 5.3 K. ECS is an emergent property of both climate feedbacks and aerosol forcing. The increase in ECS over the previous version (CESM1) is the result of cloud feedbacks. Interim versions of CESM2 had a land model that damped ECS. Part of the ECS change results from evolving the model configuration to reproduce the long-term trend of global and regional surface temperature over the twentieth century in response to climate forcings. Changes made to reduce sensitivity to aerosols also impacted cloud feedbacks, which significantly influence ECS. We report CESM2 simulations compare very well to observations of present climate. It is critical to understand whether the high ECS, outside the best estimate range of 1.5–4.5 K, is plausible.},
doi = {10.1029/2019gl083978},
journal = {Geophysical Research Letters},
number = 14,
volume = 46,
place = {United States},
year = {2019},
month = {7}
}
Web of Science
Figures / Tables:

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Figures / Tables found in this record: