Articles | Volume 24, issue 4
https://doi.org/10.5194/acp-24-2679-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-24-2679-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Opinion: Can uncertainty in climate sensitivity be narrowed further?
Steven C. Sherwood
CORRESPONDING AUTHOR
Climate Change Research Centre, UNSW Sydney, Kensington, NSW 2052, Australia
Chris E. Forest
Department of Meteorology and Atmospheric Science, The Pennsylvania State University, University Park, PA 16802, USA
Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA 16802, USA
Center for Earth System Modeling, Analysis, and Data, The Pennsylvania State University, University Park, PA, USA
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Executive editor
Equilibrium climate sensitivity (ECS), with a specific definition, has been used as a convenient measure, encapsulated in a single number, of the response of the climate to increases in long-lived greenhouse gases. The authors recall some of the history of how ECS has been estimated, by models and observations, including paleoclimate data and note recent progress in reducing uncertainty in the value of ECS. However they also note that there are important aspects of future potential climate change that are not captured by the ECS measure and therefore that there will be limited usefulness in too strong a focus on reducing uncertainty in ECS alone.
Equilibrium climate sensitivity (ECS), with a specific definition, has been used as a convenient...
Short summary
The most fundamental parameter used to gauge the severity of future climate change is the so-called equilibrium climate sensitivity, which measures the warming that would ultimately occur due to a doubling of atmospheric carbon dioxide levels. Due to recent advances it is now thought to probably lie in the range 2.5–4 °C. We discuss this and the issues involved in evaluating and using the number, pointing to some pitfalls in current efforts but also possibilities for further progress.
The most fundamental parameter used to gauge the severity of future climate change is the...
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