{"slug": "google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid", "title": "Google AI Will Reroute Hundreds Of Transatlantic Flights This Winter To Avoid Climate-Warming Contrails", "summary": "Britain's air traffic control provider NATS and Google will launch Operation Blue Skies, a £5 million, 30-month program rerouting hundreds of transatlantic flights this winter to avoid climate-warming contrails. The program, the first state-backed contrail avoidance test in oceanic airspace, will use Google AI to identify cold, humid atmospheric layers and adjust flight altitudes by up to 2,000 feet during trial windows in winters 2026-27 and 2027-28. The U.K. contributes £2.65 million, Google £1.4 million, with Imperial College London and Cambridge independently evaluating results.", "body_md": "Britain is about to run an aviation climate program that actually could matter for the climate. Most environmental efforts are greenwashing or other agendas being sold for the environment. This actually looks promising.\n\nAir traffic controllers will tell hundreds of commercial flights over the North Atlantic to climb or descend by as much as 2,000 feet this winter. Google’s artificial intelligence will help identify the cold, humid portions of the atmosphere where those aircraft are most likely to create persistent, warming contrails.\n\nThe £5 million experiment may be one of the most promising near-term efforts to reduce aviation’s climate impact, and far more consequential than sustainable aviation fuel subsidies.\n\n## Britain And Google Will Test Contrail Avoidance\n\nThe 30-month program is called [Operation Blue Skies](https://blog.google/innovation-and-ai/models-and-research/google-research/blue-skies/) which is the first state-backed test of contrail avoidance across an oceanic airspace.\n\nIt will operate in Shanwick Oceanic airspace, the eastern portion of the North Atlantic corridor managed by NATS. Atmospheric modeling attributes approximately 5% of global contrail warming to this one region, with much of it concentrated between November and February.\n\n**Two trial windows:** winters 2026–27 and 2027–28, each lasting approximately four months**Active testing:** about 20 to 40 lower-traffic days during each winter**Flights in the airspace:** approximately 10,000 during trial hours each year**Flights changed:** roughly 1% to 5%, or hundreds of flights, depending on the weather**The maneuver:** an altitude change up or down of as much as 2,000 feet, delivered through normal air traffic control channels\n\nThe U.K. is spending £219 million to subsidize home-grown ‘green’ aviation fuel. They’re spending £2.65 million towards this, with Google putting in £1.4 million of research, engineering and compute. Imperial College London and Cambridge will independently evaluate the results.\n\n## A Small Number Of Flights Cause Most Contrail Warming\n\nContrails form when water vapor in aircraft exhaust freezes around soot particles in very cold, humid air. Many disappear quickly. Others persist for hours, spread into cirrus clouds and trap heat that would otherwise escape the atmosphere.\n\nThey also reflect incoming sunlight, so an individual daytime contrail can have a cooling effect. Persistent nighttime contrails can’t reflect sunlight and are warming. The goal is to prevent the relatively small number of strongly warming contrails.\n\nA [2024 global analysis](https://acp.copernicus.org/articles/24/6071/2024/) found that about 14% of flights formed net-warming contrails, but only about 2% of all flights generated 80% of annual contrail energy forcing. And rerouting slightly can avoid this.\n\nAn [Imperial College study](https://www.imperial.ac.uk/news/195294/small-altitude-changes-could-contrail-impact/) previously estimated that changing the altitude of 1.7% of flights by 2,000 feet could reduce contrail forcing 59%, with less than a one-tenth of one percent increase in total fuel consumption.\n\nI [first wrote about this in 2020](https://viewfromthewing.com/would-airlines-solve-much-of-their-environmental-problems-if-they-just-flew-higher/). Since then we’ve learned that flying higher isn’t always the solution. The aircraft may need to climb or descend to leave a particular ice-supersaturated layer, and newer aircraft flying at higher altitudes can sometimes be more likely to encounter contrail-forming conditions.\n\n*Credit: Sander van der Wel/Wikimedia Commons (CC BY-SA 2.0)*\n\n## American Airlines And Google Already Showed That This Can Work\n\nAmerican Airlines deserves real credit for doing some of the best environmental work of any U.S. carrier here, even though it has received less attention than airlines get for subsidized fuel.\n\n[Peer-reviewed analysis](https://www.nature.com/articles/s44172-024-00329-7) used 44 matched flights, 22 assigned to avoid predicted contrail regions and 22 controls. They were about to reduce the number of flights forming a detectable trail by 64%.\n\nThen American, Google, Contrails.org and FlightKeys [ran a much larger randomized test](https://arxiv.org/abs/2603.06909) during the first five months of 2025 with about 2,400 American transatlantic flights included.\n\n- Across all 1,232 treatment-eligible flights, observable contrail formation fell 11.6% and estimated warming fell 13.7%.\n- For the 112 flights that actually followed the optimized plan, observable contrails fell 62% and estimated warming fell approximately 69%.\n- The researchers found no statistically significant fuel penalty in the flights that followed the plan.\n\n## The New Trial Tests Air Traffic Control\n\nAn individual airline can optimize its own airplane, but can’t manage the aircraft around it. It also bears any extra fuel or operational cost itself without gaining the climate benefit directly.\n\nNATS can coordinate multiple aircraft at once and determine whether moving one flight creates a conflict, displaces another flight or causes a new contrail somewhere else. And it can test whether contrail avoidance is safe and practical for controllers, whetherthe airspace produces measurably less warming overall, and whether the procedure can be copied by other air navigation providers.\n\nIf contrails account for roughly one-third of aviation’s total climate impact, a global system that eliminated half to two-thirds of their warming could reduce aviation’s overall climate impact by roughly one-sixth to one-fifth *just by using better data in air traffic*.\n\nAviation generates approximately 2.5% of annual global carbon dioxide emissions. When contrails and other non-CO₂ effects are included, it has contributed roughly 3.5% to 4% of historical warming. That includes both passenger flights and cargo.\n\nFashion and textiles by the way are estimated by the United Nations Environment Programme to generate [up to 8% of global greenhouse gas emissions](https://www.unep.org/technical-highlight/sustainable-fashion-take-centre-stage-zero-waste-day).\n\n## This Is More Promising Than Sustainable Aviation Fuel\n\nSustainable aviation fuel is supposed to deliver 65% of the reductions in the airline industry’s net-zero plan by 2050. Today, [production is 0.8% of airline fuel demand](https://www.iata.org/en/pressroom/2026-releases/06-06-saf-production-volumes-still-disappointing/) and costs up to three times as much.\n\nSustainable aviation fuel has been a convenient fiction to deflect criticism. It’s a strategy to claim a path to net zero, while seeking subsidies and with a built-in constituency to lobby for them. Plus, politicians get to announce factories, jobs and spending.\n\nContrail avoidance doesn’t produce rents for politicians to distribute. And it doesn’t even benefit hte airline’s bottom line like fuel subsidies can. Historically it hasn’t even been included in the accounting toward an airline’s net-zero carbon target.\n\n## This Is What Real Climate Work Looks Lke\n\nAir New Zealand withdrew its 2030 emissions target and left the Science Based Targets initiative in 2024. Delta recently deleted its pledge to use SAF for 10% of its fuel by 2030 and changed net zero by 2050 from a “goal” to an “aspiration.”\n\nContrail avoidance won’t put *net zero* back on track because it doesn’t remove carbon dioxide. United [separately funded some direct carbon capture work](https://viewfromthewing.com/how-united-airlines-may-wind-up-saving-the-environment/) which still has promise.\n\nDelta claimed to be the world’s first carbon-neutral airline while continuing to burn jet fuel and even owning an oil refinery. It spent more than $280 million on carbon credits between March 2020 and March 2022, including credits tied to projects with fabricated deforestation assumptions and double counting.\n\nA federal judge [has allowed a passenger to pursue damages over those claims](https://viewfromthewing.com/delta-air-lines-even-owns-an-oil-refinery-and-claimed-to-be-carbon-neutral-now-passengers-can-try-to-hold-it-accountable/) though it strikes me they amount to mere puffery, that nobody actually believed them and it’ll be tough to show anyone bought Delta flights because of the claims.\n\nDelta’s 2022 “eco-conscious” amenities announcement promoted bamboo cutlery, canned wine and reduced plastic while its own publicity photo showed the wine being poured into plastic cups. It later asked business class passengers to consider skipping meals for the environment.\n\nContrail mitigation, by contrast, leaves no visible evidence behind. But there’s a lot of science left to do to verify forecast accuracy that guides changes; a reroute must not create another contrail or impose a larger cost on surrounding traffic; results from lower-traffic winter periods over the North Atlantic may not generalize to busy continental airspace or other climates. But that’s exactly what’s being worked on.\n\nAnd if it works, passengers won’t not need to change behavior, airlines won’t need new aircraft, and and governments and airlines won’t need to ‘extend and pretend’ that biofuels are the answer.\n\n(HT: [@crucker](https://x.com/crucker/status/2089863611502022922))", "url": "https://wpnews.pro/news/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid", "canonical_source": "https://viewfromthewing.com/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid-climate-warming-contrails/", "published_at": "2026-08-21 12:04:50+00:00", "updated_at": "2026-08-21 19:44:05.925712+00:00", "lang": "en", "topics": ["artificial-intelligence", "ai-research", "ai-products"], "entities": ["Google", "NATS", "Operation Blue Skies", "Imperial College London", "University of Cambridge", "American Airlines"], "alternates": {"html": "https://wpnews.pro/news/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid", "markdown": "https://wpnews.pro/news/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid.md", "text": "https://wpnews.pro/news/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid.txt", "jsonld": "https://wpnews.pro/news/google-ai-will-reroute-hundreds-of-transatlantic-flights-this-winter-to-avoid.jsonld"}}