A framework to understand the transient climate response to
emissions
A framework to understand the transient climate response to
emissions
Global surface warming projections have been empirically connected to carbon emissions via a climate index defined as the transient climate response to emissions (TCRE), revealing that surface warming is nearly proportional to carbon emissions. Here, we provide a theoretical framework to understand the TCRE including the effects of all radiative forcing in terms of the product of three terms: the dependence of surface warming on radiative forcing, the fractional radiative forcing contribution from atmospheric CO2 and the dependence of radiative forcing from atmospheric CO2 on cumulative carbon emissions. This framework is used to interpret the climate response over the next century for two Earth System Models of differing complexity, both containing a representation of the carbon cycle: an Earth System Model of Intermediate Complexity, configured as an idealised coupled atmosphere and ocean, and an Earth System Model, based on an atmosphere–ocean general circulation model and including non-CO2 radiative forcing and a land carbon cycle. Both Earth System Models simulate only a slight decrease in the TCRE over 2005–2100. This limited change in the TCRE is due to the ocean and terrestrial system acting to sequester both heat and carbon: carbon uptake acts to decrease the dependence of radiative forcing from CO2 on carbon emissions, which is partly compensated by changes in ocean heat uptake acting to increase the dependence of surface warming on radiative forcing. On decadal timescales, there are larger changes in the TCRE due to changes in ocean heat uptake and changes in non-CO2 radiative forcing, as represented by decadal changes in the dependences of surface warming on radiative forcing and the fractional radiative forcing contribution from atmospheric CO2. Our framework may be used to interpret the response of different climate models and used to provide traceability between climate models of differing complexity.
15003
Williams, Richard G.
2155309e-1c07-4365-b46a-04baeb2fb63c
Goodwin, Philip
87dbb154-5c39-473a-8121-c794487ee1fd
Roussenov, Vassil M.
dd3b39c7-9a7a-476d-b7eb-4e5add1446a1
Bopp, Laurent
771de655-3caf-42ba-8231-40f17d4addc4
21 January 2016
Williams, Richard G.
2155309e-1c07-4365-b46a-04baeb2fb63c
Goodwin, Philip
87dbb154-5c39-473a-8121-c794487ee1fd
Roussenov, Vassil M.
dd3b39c7-9a7a-476d-b7eb-4e5add1446a1
Bopp, Laurent
771de655-3caf-42ba-8231-40f17d4addc4
Williams, Richard G., Goodwin, Philip, Roussenov, Vassil M. and Bopp, Laurent
(2016)
A framework to understand the transient climate response to
emissions.
Environmental Research Letters, 11 (1), .
(doi:10.1088/1748-9326/11/1/015003).
Abstract
Global surface warming projections have been empirically connected to carbon emissions via a climate index defined as the transient climate response to emissions (TCRE), revealing that surface warming is nearly proportional to carbon emissions. Here, we provide a theoretical framework to understand the TCRE including the effects of all radiative forcing in terms of the product of three terms: the dependence of surface warming on radiative forcing, the fractional radiative forcing contribution from atmospheric CO2 and the dependence of radiative forcing from atmospheric CO2 on cumulative carbon emissions. This framework is used to interpret the climate response over the next century for two Earth System Models of differing complexity, both containing a representation of the carbon cycle: an Earth System Model of Intermediate Complexity, configured as an idealised coupled atmosphere and ocean, and an Earth System Model, based on an atmosphere–ocean general circulation model and including non-CO2 radiative forcing and a land carbon cycle. Both Earth System Models simulate only a slight decrease in the TCRE over 2005–2100. This limited change in the TCRE is due to the ocean and terrestrial system acting to sequester both heat and carbon: carbon uptake acts to decrease the dependence of radiative forcing from CO2 on carbon emissions, which is partly compensated by changes in ocean heat uptake acting to increase the dependence of surface warming on radiative forcing. On decadal timescales, there are larger changes in the TCRE due to changes in ocean heat uptake and changes in non-CO2 radiative forcing, as represented by decadal changes in the dependences of surface warming on radiative forcing and the fractional radiative forcing contribution from atmospheric CO2. Our framework may be used to interpret the response of different climate models and used to provide traceability between climate models of differing complexity.
Text
erl2016_wgrb.pdf
- Version of Record
Available under License Other.
More information
Accepted/In Press date: 16 December 2015
e-pub ahead of print date: 21 January 2016
Published date: 21 January 2016
Organisations:
Paleooceanography & Palaeoclimate
Identifiers
Local EPrints ID: 386248
URI: http://eprints.soton.ac.uk/id/eprint/386248
ISSN: 1748-9326
PURE UUID: 842c5ebf-ec2e-4b08-8aee-f3f16bb63ea4
Catalogue record
Date deposited: 22 Jan 2016 10:21
Last modified: 15 Mar 2024 03:47
Export record
Altmetrics
Contributors
Author:
Richard G. Williams
Author:
Vassil M. Roussenov
Author:
Laurent Bopp
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics
