Observing long-lived longwave contrail forcing

Sonabend-W, Aaron; Geraedts, Scott; Goyal, Nita; Ng, Joe Yue-Hei; Van Arsdale, Christopher; McCloskey, Kevin

doi:10.5194/amt-19-1951-2026

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.

https://doi.org/10.5194/amt-19-1951-2026

© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 19, issue 5

Research article

|

18 Mar 2026

Research article |

| 18 Mar 2026

Observing long-lived longwave contrail forcing

Aaron Sonabend-W, Scott Geraedts, Nita Goyal, Joe Yue-Hei Ng, Christopher Van Arsdale, and Kevin McCloskey

Data sets

ERA5 hourly data on pressure levels from 1940 to present Hans Hersbach et al. https://doi.org/10.24381/cds.bd0915c6

Collated dataset of sampled pixels for observing long-lived longwave contrail forcing Aaron Sonabend-W et al. https://doi.org/10.5281/zenodo.18929653

Model code and software

Causal model regression code for observing long-lived longwave contrail forcing Aaron Sonabend-W et al. https://doi.org/10.5281/zenodo.18929469

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.