Original article by Ben Webster and Lucas Amin republished from openDemocracy under a Creative Commons Attribution-NonCommercial 4.0 International licence.

Campaigners say the lobbying tactics used to argue against tougher measures on emissions echo those of the 20th century tobacco industry

Airlines have been accused of using a “typical climate denialist” strategy after downplaying decades of scientific research on aviation emissions to block tougher regulations.

Campaigners said the lobbying tactics echoed those of the 20th century tobacco industry, which fought stricter measures by magnifying minor doubts on the health risks of smoking.

Documents obtained by openDemocracy show airlines and airports privately told the government there was too much uncertainty about the additional warming effects of flights to justify introducing new policies to tackle them.

But senior climate scientists contradicted the industry’s claims, saying the science is well established on what are known as aviation’s “non-CO2 effects”.

These are caused by emissions at high altitude of water, nitrous oxides, sulphur dioxide and particulate matter, with aircraft vapour trails, also known as contrails, a particular problem because they form clouds at high altitude that trap heat radiated from the Earth.

The Intergovernmental Panel on Climate Change estimated in a special report in 1999 that the total historic impact of aviation on the climate was two to four times greater than from its CO2 emissions alone.

Research in 2021 largely confirmed those findings and concluded aviation emissions were warming the climate at “approximately three times the rate of that associated with aviation CO2 emissions alone”. An EU study from 2020 also found non-CO2 emissions warm the planet about twice as much as CO2 emissions, but acknowledged there were “significant uncertainties”.

The Department for Transport considered regulating these non-CO2 impacts and asked for views on the issue in a consultation in 2021 on its proposed “Jet Zero strategy”.

Responses from airlines and airports, obtained under FOI by openDemocracy, reveal several used the same tactic of arguing the science was too uncertain to justify policies to address non-CO2 effects. Several recommended instead that the government should limit its action on the issue to funding further research into it.

‘A bit of a joke’

Airlines UK, a trade body that lobbies for airlines including British Airways (BA), easyJet and Virgin Atlantic, told the DfT that “the science around these [non-CO2 impacts] is not yet robust enough to form reduction targets”.

When asked during the Jet Zero consultation what could be done to tackle non-CO2 impacts, Ryanair said it was “too early to say until impact is better understood”.

Low-cost airline Wizz Air told the DfT: “There is too high a level of uncertainty of non-CO2 emission contribution to climate change for a policy to be formed.”

Airlines UK, Ryanair and Wizz – alongside others across the industry – called on the DfT to instead fund further research into the science of non-CO2 impacts.

The tactic appears to have worked, with the DfT announcing in the Jet Zero strategy last year that more work would be done with scientists and the industry to understand the issue.

The DfT did, however, say the government was “exploring whether and how non-CO2 impacts could be included in the scope of the UK ETS (emissions trading scheme)”.

Professor Piers Forster, an atmospheric physicist and member of the independent Climate Change Committee, told openDemocracy it was “completely wrong” for the aviation industry to claim the science on aviation’s non-CO2 effects was too uncertain to address them.

He said: “It’s a bit of a joke to say the effects are too uncertain to do anything about. We see their contrails and we’ve known for over 20 years that they are warming the planet. The industry should not hide behind uncertainty.”

He added that “the non-CO2 effects absolutely have to be accounted for in some way and action should be taken to reduce them”.

Milan Klöwer, a climate physicist at Massachusetts Institute of Technology, said airlines were adopting a “typical climate denialist strategy” by overstating the level of uncertainty about non-CO2 effects.

“Even in the best case they roughly double the effect of CO2 emissions on the climate,” he said.

He called on airlines to start accounting for their non CO2 effects and invest more in solutions, such as alternative fuels, which reduced those effects.

Rob Bryher, aviation campaigner at climate charity Possible, said: “These documents show that airlines cannot be trusted to decarbonise on their own. Demand management solutions like a frequent flyer levy, introducing fuel duty, carbon pricing, or management of airport capacity are going to be crucial.”

Matt Finch, UK policy manager of campaign group Transport & Environment, said: “Aviation’s non-CO2 impacts are somewhere between huge and absolutely massive. But the industry doesn’t want you to know that. Instead of confronting its environmental problems head-on, the industry copies the tobacco industry of the ’50s and the oil industry of the ’70s in casting doubt and disbelief around the science.”

BA said it was working with academics and experts on non-CO2 impacts of flying while Sustainable Aviation, an industry group that includes airlines, said it was committing to addressing them but reiterated more research was needed. Wizz Air said it was already addressing the impacts through a range of measures.

Some airlines ignore non-CO2 effects in schemes they support to help passengers calculate and offset the emissions of their flights.

BA’s emissions calculator states a one way flight from London Heathrow to New York emits 348kg CO2E (carbon dioxide equivalent) and charges £3.97 for offsetting.

Atmosfair, a German non-profit organisation which supports the decarbonisation of flying, calculates the same journey on a Boeing 777-200 – an aircraft type used by BA – emits 896kg and charges 21 euros (£18.37) for offsetting. Atmosfair’s emissions total comprises 308kg of CO2 emissions and 587 kg equivalent for “climate impact of contrails, ozone formation etc”.

While the DfT has so far failed to act on non-CO2 effects, they are mentioned in official advice to companies from the Department for Business Energy and Industrial Strategy on how to report their emissions.

It says: “Organisations should include the indirect effects of non-CO2 emissions when reporting air travel emissions to capture the full climate impact of their travel.”

A DfT spokesperson said: “Our Jet Zero Strategy confirmed our aim of addressing the non-CO2 impacts of aviation, by developing our understanding of their impact and possible solutions, and the UK is one of the leading countries working to address this issue.”

Sustainable Aviation Fuel

International Airlines Group (IAG), which owns BA, Vueling and Aer Lingus, told DfT’s Jet Zero consultation it could address non-CO2 emissions by supporting “sustainable aviation fuel” (SAF).

SAF is a jet fuel made from sources which the industry claims are sustainable, including cooking oil and animal fat. It performs in a similar way to kerosene but can produce up to 80% less CO2 depending on how it is made. It potentially also reduces contrails.

IAG told the Jet Zero consultation SAF was “the only viable solution for decarbonising medium and long haul flights”, which account for about 70% of global aviation emissions.

But further documents obtained by openDemocracy reveal IAG then lobbied the DfT to water down its SAF mandate.

In response to a separate consultation, IAG argued the SAF mandate should only cover flights within the UK or to the EU, and not the long haul flights on which British Airways makes most of its profits.

IAG also lobbied against a proposal to ban airlines from dodging the mandate by filling their tanks with cheap kerosene at overseas airports – a practice known as “tankering”.

A BBC Panorama investigation in 2019 revealed tankering by BA and other airlines was creating small financial savings but unnecessary carbon emissions.

IAG also argued against a proposal aimed at building demand for “power-to-liquid” jet fuel, which is produced by combining hydrogen made by renewable energy with carbon captured from the atmosphere.

Unlike other so-called sustainable jet fuels, power-to-liquid fuel does not involve a feedstock needed by other industries to decarbonise, such as used cooking oil or animal fat.

IAG called it “a very expensive pathway to directly decarbonise aviation”.

Sustainable Aviation, an industry group that includes airlines, said: “We are committed to addressing [non-CO2] impacts based on the scientific evidence, but further research is key to developing effective mitigation solutions, for example the use of sustainable aviation fuels (which contain lower contrail forming particulates), alongside steps such as optimising flight routes to avoid contrail formation.”

BA, IAG’s principal airline, said: “We are actively engaging with academics, experts within the industry and the government’s Jet Zero Council to take proactive steps to look into non-CO2 impact.”

Wizz Air said it was mitigating non-CO2 effects “through route optimisation and jet fuel improvements” and by using Airbus A321neo aircraft which reduced NOx emissions by 50%.

Ryanair did not respond to a request for comment.

Original article by Ben Webster and Lucas Amin republished from openDemocracy under a Creative Commons Attribution-NonCommercial 4.0 International licence.