Articles | Volume 19, issue 5
https://doi.org/10.5194/amt-19-1951-2026
© 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/amt-19-1951-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Observing long-lived longwave contrail forcing
Aaron Sonabend-W
Google Research, Mountain View, CA, USA
Scott Geraedts
Google Research, Mountain View, CA, USA
Nita Goyal
Google Research, Mountain View, CA, USA
Joe Yue-Hei Ng
Google Research, Mountain View, CA, USA
Christopher Van Arsdale
Google Research, Mountain View, CA, USA
Google Research, Mountain View, CA, USA
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Aaron Sarna, Vincent Meijer, Rémi Chevallier, Allie Duncan, Kyle McConnaughay, Scott Geraedts, and Kevin McCloskey
Atmos. Meas. Tech., 18, 3495–3532, https://doi.org/10.5194/amt-18-3495-2025, https://doi.org/10.5194/amt-18-3495-2025, 2025
Short summary
Short summary
Contrails, the clouds formed by aircraft, are have a substantial climate impact. Determining which flight formed each contrail is a critical step to decreasing this impact. We introduce a dataset of synthetic contrail observations with known flight attributions that can be used to develop and assess geostationary-satellite-based contrail-to-flight attribution systems. We additionally introduce a new attribution algorithm and show that it outperforms previous methods.
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Short summary
Airplane condensation trails trap heat, but their full warming effect is hard to measure because they blend into natural clouds. Using satellite observations, weather data, flight paths, and a causal inference framework, we isolated this effect without simulations or contrail masks. We found contrails trap 46.9 gigajoules of heat per kilometer flown over the Americas. This provides a crucially missing observation-based estimate of a major portion of aviation’s environmental impact.
Airplane condensation trails trap heat, but their full warming effect is hard to measure because...