Articles | Volume 25, issue 20
https://doi.org/10.5194/acp-25-12875-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-12875-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Oct 2025
Research article |
| 17 Oct 2025
| 17 Oct 2025
Zero-dimensional contrail models could underpredict lifetime optical depth
Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom
Sebastian D. Eastham
Department of Aeronautics, Imperial College London, London, SW7 2AZ, United Kingdom
Jerome P. Jarrett
Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom
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Caleb Akhtar Martínez, Annemarie Lottermoser, Simon Unterstrasser, Sebastian D. Eastham, and Jerome P. Jarrett
EGUsphere, https://doi.org/10.5194/egusphere-2026-5576, https://doi.org/10.5194/egusphere-2026-5576, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We study how different computer models predict the climate impact of contrails, the ice clouds that form behind aircraft. Efforts to reduce their impact depend on these models. By comparing simpler and more detailed models under the same weather conditions, we find that modelling choices can lead to substantially different results, even when comparing models of similar complexity. This suggests that contrail mitigation decisions should be made in a way that is robust to modelling differences.
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
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We study how different computer models predict the climate impact of contrails, the ice clouds that form behind aircraft. Efforts to reduce their impact depend on these models. By comparing simpler and more detailed models under the same weather conditions, we find that modelling choices can lead to substantially different results, even when comparing models of similar complexity. This suggests that contrail mitigation decisions should be made in a way that is robust to modelling differences.
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Short summary
Contrails are clouds that form behind aircraft and can warm the atmosphere as much as carbon dioxide emissions from those planes. This work compares two contrail models of different complexities to understand their lifecycle and impact. The models differ in how contrails evolve over time, implying that we may be significantly underestimating their climate impact. This highlights the need for model diversity and more evaluation against observations of long-lived contrails.
Contrails are clouds that form behind aircraft and can warm the atmosphere as much as carbon...
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