Air Travel Could Account for 25% of Global Warming By 2050

According to a recent United Nations report, the global aviation sector could consume as much as 27 percent of the world’s carbon budget by 2050. Even within the most optimistic scenario, airplanes will still be responsible for 12 percent of the world’s carbon emissions mid-century if the world will be able to limit climate change to 1.5°C.

The report comes as global aviation and travel organizations, including the International Air Transport Association (IATA), have pledged to cap emissions from projected 2020 figures. The IATA says it has pushed its members to contribute to the organization’s goals of improving overall fuel efficiency 1.5 percent annually through the end of this decade; by 2050, IATA says it aims to lower carbon dioxide emissions 50 percent by 2050 from 2005 levels.

But the UN’s International Civil Aviation Authority (ICAO) says such efforts may not be enough.

A large part of the problem is that the number of people worldwide who will fly overseas is expected to surge. Even today, flying is still a relative luxury for most of the world’s citizens, with recent estimates suggesting 18 percent of people have ever flown on an airplane. But the globe’s middle class is growing, more discounted carriers are emerging, and as a result, flying long distances has become relatively affordable.

As The Guardian has concluded, international travel has boomed the past few decades as the end of the Cold War opened up more of the world to tourism. Twenty years ago, 536 million trips were made abroad; that figure topped 1 billion in 2012. Meanwhile, tourism has become entrenched in the global economy: a 2016 report concluded that worldwide, one in 11 people worked in the tourism sector.

Advances in aviation will most likely fuel this boom, even while the aviation sector promises to do what it can to become more sustainable. The ICAO report mentions the potential to reintroduce jets traveling at supersonic speeds – without the “sonic boom,” expense and technical problems that bedeviled the Concorde until it completed its final flight in 2003.

One massive challenge is that the airlines lack scalable options for fuel. Indeed, several carriers such as KLM and United have tinkered with biofuel blends for their aircraft. Other companies, such as Virgin Atlantic, have explored the possibility of using emissions from carbon-heavy facilities such as steel mills. But establishing a reliable source of fuels derived from algae, waste or other alternative feedstocks has resulted in many press-worthy ribbon-cutting events, but little technological advancement. While its round-the-world solar-powered flight was impressive, do not expect Solar Impulse to inspire any new developments: that project was more about showcasing the overall potential of clean technology rather than transforming how planes can circumvent the globe.

Other initiatives have helped chip away at aviation’s massive footprint. Discount carriers, appearing to be more mindful of their operations’ impact on the global environment, have done what they can to become leaner. EasyJet and Southwest are amongst the examples. The modernization of air traffic control systems, including a recent proposal floated by the Trump White House, can help chip away at the industry’s emissions. Other programs achieve very little: carbon offsets, as in the program operated by IATA, provide little help in resolving airlines’ pesky emissions challenges.

As a result, the ICAO report concedes that despite all these incremental improvements, there could be a shortfall of 1.039 billion metric tons of carbon emissions in 2050. That gap represents what is technologically possible and what is actually needed for the industry to limit emissions to 2020 levels. “The uncertainty associated with future aviation demand is notably larger than the range of contributions from technology and operational improvements,” conclude the report’s authors.

Some analysts believe the only way to solve the aviation sector’s emissions riddle is to curb its relentless growth. If nations adhere to their climate change mitigation plans, economics may drive those answers. Last year, an assessment of the cost of a new runway at London’s Heathrow Airport revealed that its costs behind ensuring the United Kingdom stayed compliant with legally binding climate change goals meant discount carriers would no longer be able to fly from that airport. Meanwhile, citizens in cities such as Barcelona and Venice have begun to push back against unchecked tourism, posing a difficult question for local politicians: can governments limit the number of people coming to their cities and countries in the name of sustainable development?

Image credit: Tony Hisgett/Flickr