Reducing flights to save the environment

Environmentalists see aircraft as one the biggest contributors to carbon emissions. So could drastic measures like banning non-essential flights be the answer? Would the flying public and airlines be willing to make this sacrifice?

Politicians work on the principle that if you say something often enough, people might confuse it with the truth. The debate around banning or heavily taxing flights is a prime case in point.

The solution, according to a number of environmental groups, is to replace aircraft with trains. While this could make sense in a first world economy where transport infrastructure is already in place (Europe and North America), the problem arises in the economies of Africa and Asia.

Growing economies argue that they have a right to attain the level of existing first world countries without penalty, citing that pollution was not their doing in the first place. A valid point.

In the October Journal of Transport Geography under the title of ‘Banning super short-haul flights: Environmental evidence or political turbulence?’ by Frédéric Dobruszkes, Giulio Mattioli and Laurette Mathieu, the authors posted a series of Tweets giving the highlights of what they found, starting with this one:

After studying all commercial flights from 31 European countries, they found that flights shorter than 500 kilometres (310 miles) account for 28% of all flights but just 5.9% of fuel burnt. Conversely, they found that 6.2% of departures are for flights longer than 4,000 kilometres (2,485 miles), which burn 47% of the fuel.

Just think about that for a minute. Twenty-eight flights in every 100 burn way less fuel than the sixteen long-haul flights. The researchers concluded that reducing the impact of aviation on climate requires the targeting of longer flights, not short-haul flights.

“We conclude that targeting shorter flights, which often exist to alleviate physical obstacles imposed by physical geography, will contribute little to reducing the impact of aviation on climate and that policy initiatives that target longer flights are urgently needed,” said a tweet.

So why is the heat turned up on short-haul flights? As Mattioli says in his series of tweets, banning super-short-haul flights makes sense as a “first step”, even if the actual emission reductions are low. However, he believes that the emission impact of “short flights is exaggerated,” while the impact of long-haul flights and their extra emissions are “not part of the discussion.” He lists three ways of reducing transport, which he says change the conversation “quite a bit.”

• Improve technical efficiency.
• Shift to other modes of transport.
• Avoid travel if possible.

Put succinctly, his view is that society needs to talk about cutting back on long-haul flights and finding ways to shift those trips to shorter distances adding, “that’s where the emission reductions are.” For those who want to learn more, he points to a study called Sustainable Transportation, with the details on the Twitter thread. This study found that the growth in aviation emissions between 1996 and 2018 came about because of the “provision of air services on pre-existing and new routes mostly longer than 1,000 km”.

Thankfully, engine makers like Pratt & Whitney, General Electric and Rolls Royce have made significant progress in reducing fuel burn, emissions and noise from new-generation engines. Manufacturers have also introduced newer aircraft that cut fuel burn on long-haul flights, such as the Airbus A350, A330neo and the Boeing 787 Dreamliner.

“Policy-makers have an obvious interest in focusing on short-haul flights as it’s often a very low-cost measure that does not upset everyone. But it doesn’t help that much with emissions, so if you care about climate you need to demand more, a lot more,” says Mattioli.

Banning short-haul flights won’t resolve aviation’s bigger problem. According to European air traffic management body Eurocontrol, long-haul flights account for 6% of all the continent’s flights but produced a disproportionate 52% of emissions — making the implementation of biofuel an increasingly burning issue.

The problem is competition amongst airlines. Airlines should all work together and with regulators to get fewer aircraft on routes. It is a known fact that many airlines fly aircraft with countless empty seats. Airlines should report to regulators about seat occupancy per trip. This way aircraft can be filled to capacity, with frequency of trips reduced.

The basic thinking is ‘fewer flights, less fuel burned, less pollution.’

John Hyland, the EU spokesperson for the group said further: “The EU and European governments, France included, should ban all short flights when passengers can use less polluting transport like rail or bus.” 

A 2021 scientific combined study from Oxford University, Manchester University and Rutherford Appleton Laboratory suggests that we need to reduce the amount of flying. The article is called ‘Quantifying aviation’s contribution to global warming’ and analyses global warming over different time periods, accounting for changes within the aviation industry, which accounts for four percent of all warming.

The basics: If there was a 2.5 percent decrease in air travel every year from now on, the study says the aviation industry would cause no further global warming at all. The effects would be immediate.