Google and the UK Launch Operation Blue Skies: Steering Planes Around Contrails Over the Atlantic
The UK government and Google are launching Operation Blue Skies, a groundbreaking trial aimed at reducing aviation’s climate impact by routing aircraft around contrails across the North Atlantic. This initiative utilizes AI-powered forecasts to predict and avoid contrail formation, which is responsible for approximately one-third of aviation’s total climate impact.
The Science Behind Contrails
Contrails are the thin white lines often seen behind aircraft, formed when water vapor in jet exhaust freezes around soot particles into ice. While many dissipate quickly, cold, humid conditions can cause them to persist and spread into cirrus clouds, trapping heat. Paul Hodgson, Google’s technical lead on the trial, described these contrails as "sky graffiti" to a BBC interview. Scientists estimate that contrail warming contributes significantly to aviation’s climate footprint, with some studies suggesting it could be either a large or very large problem.
Operation Blue Skies: Details of the Trial
Operation Blue Skies operates within Shanwick airspace, covering the eastern half of the North Atlantic corridor. This region accounts for about 5% of global contrail warming, primarily during winter. The trial involves:
- AI Forecasting: Google employs AI models leveraging satellite imagery, flight data, and Met Office weather models to predict contrail formation.
- Air Traffic Control (ATC) Integration: Forecasts are communicated to NATS, the UK air traffic control provider, enabling controllers to instruct pilots to adjust their altitude by up to 2,000 feet to avoid contrails.
- Standard Communication: Deviations from standard routes are handled through existing ATC channels.
- Timing and Scope: The trial focuses on evening and night flights, when contrail warming is strongest due to the absence of sunlight reflection during the day. It will run for two winters (2026-2027 and 2027-2028), with around 10,000 flights per year potentially re-routed.
Funding and Partners
The £5 million, 30-month program is funded by a mix of public and industry contributions:
- £2.65 million from the Department for Transport through the ATI Programme.
- Industry partners contribute the remainder, with Google providing £1.4 million in kind through research, engineering time, and computing resources.
The consortium comprises UK entities, including Google UK, NATS, Contrails.org, Imperial College London, University of Cambridge, and the Met Office. The ATI emphasized that all government funding is allocated to academic, non-profit, and aviation partners, not Google.