Google Teams Up with UK Government to Reduce Contrail Warming

Google is collaborating with the UK government to launch Operation Blue Skies, an innovative trial aimed at reducing climate-warming contrails from aircraft. Contrails are formed when water vapour in jet exhaust freezes into ice, trapping heat and contributing to global warming. The project focuses on the North Atlantic airspace, where about 5% of global contrail warming occurs.

The trial uses AI forecasts built by Google to predict where persistent contrails will form. These forecasts are then shared with NATS, the UK air traffic control provider, which instructs pilots to change altitude to avoid these areas. This manoeuvre is routine and only requires a deviation of up to 2,000 feet.

The trial is expected to run for two winters, from 2026 to 2028, with around 20-40 test days per winter. The consortium behind the project includes Google UK, NATS, Contrails.org, Imperial College London, and the University of Cambridge, among others. The £5mn effort is being led by the Aerospace Technology Institute (ATI), which estimates that contrail warming accounts for roughly a third of aviation's total climate impact.