Air travel must be radically rethought if the world is to meet net zero goals, a new report warns. The aviation industry cannot achieve net zero by 2050 through technological improvements and sustainable aviation fuels alone and must prepare for a fundamental reduction and restructuring of air travel, according to a new report written by Chris Lyle of Air Transport Economics with contributions from International Centre for Responsible Tourism global founder Harold Goodwin.
Reframing air transport for net zero alongside economic and social justice argues that the industry’s current assumption of continued growth is incompatible with the scale of the climate challenge. Without a radical change of direction, aviation emissions could at least double by 2050, even as other sectors of the economy decarbonise.
The report’s lead author, Chris Lyle argues that aviation is already “widely unsustainable” in its contribution to climate change and that the sector must increasingly confront limits on demand, particularly for long-haul flights.
Aviation currently accounts for around 2.5% of global carbon dioxide emissions, but its overall contribution to climate change is substantially greater because of the additional effects of emissions released at altitude. Tourism as a whole accounts for an estimated 8% to 10% of global greenhouse gas emissions, with aviation the largest and increasingly dominant component.
The report warns that the technologies currently being promoted as the solution will not deliver the necessary reductions quickly enough. Sustainable aviation fuel (SAF), for example, remains expensive and supply is severely constrained. Hydrogen and electric aircraft may eventually transform shorter-distance flying but are unlikely to provide a solution for long-haul aviation.
“A significant proportion of the aeroplanes that will be flying in 2050 are already in the air or in the delivery chain,” the report states. “Many of the rest will also be crucially dependent on SAF, but supply will be woefully inadequate.”
The implication is that efficiency improvements and new technology, while important, cannot be relied upon to solve aviation’s climate problem.
“Even with all current mitigation measures taken together, it is increasingly evident that the only way civil aviation will achieve net-zero by 2050 will necessitate some form of demand management,” the report says.
The authors stress that this should not mean simply restricting everyone’s ability to fly. Instead, governments should determine which forms of aviation deliver the greatest economic and social value and give those services priority as emissions limits become tighter.
The report places this question firmly within the context of global inequality. Less than 10% of the world’s population flies in any given year, and only around 2% to 4% fly internationally. Research cited by the report suggests that just 1% of the world’s population accounts for half of the emissions produced by the 10% who fly.
At the same time, some of the countries most dependent on aviation have made relatively little contribution to global emissions. Least Developed Countries, Landlocked Developing Countries and Small Island Developing States account for only around 5.4% of tourism transport emissions, yet many rely heavily on aviation for tourism, employment and foreign exchange.
The report therefore argues against a blunt approach to reducing aviation demand and calls for policies that recognise these very different circumstances.
One proposal is for governments to introduce legally enforceable limits on aviation emissions through airport capacity and slot allocation. Airports would become accountable for the emissions generated by the flights they enable, with progressively tighter targets on the way to net zero by 2050.
Where flights have to be reduced, priority could be given to those providing essential connectivity and the greatest economic and social benefits, while taking account of emissions per passenger and whether lower-emission alternatives exist.
The authors acknowledge that their proposals would be politically difficult. Aviation operates through a complex international regulatory system and the industry has significant influence over policy. But they argue that voluntary action by airlines, passengers and tourism businesses will not be enough.
Governments must continue to support technological innovation and sustainable aviation fuels, but must also introduce measures to control demand if emissions reductions fail to materialise at the necessary speed.
The report concludes that the fundamental question is no longer simply how to make aviation greener, but what aviation should be prioritised for in a carbon-constrained world.
“Direct capping of flight emissions is not just an option it is rapidly becoming an imperative if society is to have any chance of thwarting the existential threat of climate change,” it concludes.
The full report can be read and downloaded here Reframing air transport for net zero alongside economic and social justice
Picture credit: Pexels Sydney Haws
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