Research article
| 
10 Jul 2026
Research article |
| 10 Jul 2026
| 10 Jul 2026
Concept of risk-aware contrail avoidance strategies
Audran Borella
CORRESPONDING AUTHOR
Institut Pierre-Simon Laplace, Sorbonne Université/CNRS, Paris, France
now at: Klima Consulting, Paris, France
Cameron Steer
Institut Pierre-Simon Laplace, Sorbonne Université/CNRS, Paris, France
Nicolas Bellouin
Institut Pierre-Simon Laplace, Sorbonne Université/CNRS, Paris, France
Department of Meteorology, University of Reading, Reading, UK
Olivier Boucher
Institut Pierre-Simon Laplace, Sorbonne Université/CNRS, Paris, France
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Andy Jones, Jim M. Haywood, Adam A. Scaife, Olivier Boucher, Matthew Henry, Ben Kravitz, Thibaut Lurton, Pierre Nabat, Ulrike Niemeier, Roland Séférian, Simone Tilmes, and Daniele Visioni
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Simulations by six Earth-system models of geoengineering by introducing sulfuric acid aerosols into the tropical stratosphere are compared. A robust impact on the northern wintertime North Atlantic Oscillation is found, exacerbating precipitation reduction over parts of southern Europe. In contrast, the models show no consistency with regard to impacts on the Quasi-Biennial Oscillation, although results do indicate a risk that the oscillation could become locked into a permanent westerly phase.
Yves Balkanski, Rémy Bonnet, Olivier Boucher, Ramiro Checa-Garcia, and Jérôme Servonnat
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Earth system models have persistent biases that impinge on our ability to make robust future regional predictions of precipitation. For the last 15 years, there has been little improvement in these biases. This work presents an accurate representation of dust absorption based upon observed dust mineralogical composition and size distribution. The striking result is that this more accurate representation improves tropical precipitations for climate models with too weak an African monsoon.
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Short summary
Targeted contrail avoidance consists of rerouting aircraft to minimise the formation of warming contrails. However, current predictions of contrail climate impact are highly uncertain. In this study, we show that some reroutings that were predicted to be beneficial for the climate are in fact damaging it. We further demonstrate that the risk of unintentionally damaging the climate can and should be included in the decision-making of contrail avoidance.
Targeted contrail avoidance consists of rerouting aircraft to minimise the formation of warming...
