Articles | Volume 23, issue 17
https://doi.org/10.5194/bg-23-6211-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-6211-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
07 Sep 2026
Research article |
| 07 Sep 2026
| 07 Sep 2026
Asymmetry in carbon cycle feedbacks and transient climate response under positive and negative CO2 emissions
V. Rachel Chimuka
CORRESPONDING AUTHOR
Geography Department, Simon Fraser University, Burnaby, BC V5A 1C1, Canada
Kirsten Zickfeld
Geography Department, Simon Fraser University, Burnaby, BC V5A 1C1, Canada
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Short summary
Using Earth system model simulations, we show that carbon cycle feedbacks are asymmetric under positive and negative CO2 emissions due to non-linear responses to CO2 and temperature change, and asymmetric ocean circulation changes. These asymmetries propagate onto the asymmetry in the transient climate response to cumulative emissions. Our work emphasizes the need to evaluate climate and carbon metrics under negative emissions rather than applying metrics from positive emissions scenarios.
Using Earth system model simulations, we show that carbon cycle feedbacks are asymmetric under...
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