When Swedish teen climate activist Greta Thunberg skipped flying in favor of a two-week Atlantic crossing to reach the United Nations Climate Summit in New York in September 2019, the nascent flight-shaming movement really took off. Protest groups such as Greenpeace and Extinction Rebellion are fueling the campaign by highlighting aviation’s role in global warming. The phenomenon could lead to lower passenger numbers, higher taxes on flights, and changes in jet and fuel technology.

1. How did the movement begin?

The movement is named for the Swedish term “flygskam,” or flight shame, the emotion it’s meant to provoke. It started in 2017 when five Swedish celebrities including Thunberg’s mother, opera singer Malena Ernman, wrote a newspaper piece pledging to give up air travel for the sake of the environment. Debate grew more lively the next year with another newspaper column and a surge in followers of the Facebook group Tagsemester, meaning train vacation, promoting rail as an alternative to flying. At the same time, following Thunberg’s example, students started skipping school all over the world to join what are known as climate strikes, demanding greater action to combat climate change.

2. Is flying really shameful?

The aviation industry produced around 2.4% of all human-induced carbon dioxide emissions in 2018, or about 12% of the total from the transport industry. Its share of the overall impact on global warming reaches as much as 5% when the calculation takes into account aviation’s other effects on the earth’s upper atmosphere, such as nitrogen oxide emissions and the influence on cloud formation that may cause higher temperatures. International agreements on climate change have left it to individual countries to include domestic air travel in their carbon calculations. Regulating emissions from international flights, which are responsible for two thirds of all airplane fuel consumption, are to be worked out through the UN’s International Civil Aviation Organization. If other sectors de-carbonize by mid-century and aviation doesn’t, with rising demand for flights tripling the industry’s emissions, they could account for as much as one quarter of the global total, according to an ICAO projection. That would make flights the single biggest emitter of CO2.

3. Has the movement had any real impact?

Finding evidence that people are forgoing airplane trips for environmental reasons isn’t easy because motives don’t show up in the numbers. Some clues are starting to emerge in countries where the population is especially sensitive to climate issues. In Sweden, the number of passengers flying the flag carrier SAS dropped last year, while the national airports operator reported a 4% decline in people flying to or from the country’s airports, mostly due to weaker domestic travel. Both entities have cited the climate debate as one of the reasons. A similar trend emerged in Germany. Attitudes may also be changing among the flying public. Swiss bank UBS Group AG surveyed about 2,000 people in Germany and the U.S. in May and found between a fifth and a quarter of respondents had reduced their flights in the last year on environmental concerns. At the same time, Europe’s three largest discount carriers are reporting rising passenger numbers.

4. Have rail operators benefited?

A passenger traveling by rail generates roughly three or four times less CO2 than flying. While conclusive evidence hasn’t emerged in Europe that flight shaming has pushed more people to opt for the train, fast links criss-crossing countries such as Germany and France, as well as whisking passengers between London, Paris, Brussels and Amsterdam, are popular. Even before the movement took hold, travelers became more willing to choose rail for trips as long as four hours over hour-long flights. The cutoff used to be around three hours, but increasing airport hassle and flight delays due to the continent’s crowded skies have changed the equation. Night sleepers are even poised to make a comeback on selected routes such as Vienna-Brussels. In Germany, operator Deutsche Bahn says travel by rail is on the rise and breaking records every year.

5. Are governments getting involved?

Under the 1944 Chicago Convention promoting international civil aviation, countries aren’t allowed to tax the fuel onboard an aircraft arriving from another nation. They can tax aviation fuel for domestic flights, although in the European Union, only the Netherlands does so. By comparison, road and railway fuels are subject to relatively high levies in the EU. The car industry is also under enormous pressure to sell electric vehicles or face hefty EU fines for missing tough pollution targets. As part of a push to be carbon neutral by 2050, the bloc plans to overhaul energy-taxation laws, and some countries favor ending exemptions on airplane fuel. In November, nine countries called for measures to ensure fairness in what airlines pay for damaging the environment. While the EU regulates emissions on flights within the bloc through its carbon market, international routes are exempt.

6. How has the aviation industry reacted?

It has gone on the defensive. Executives have complained about being scapegoated while campaigning against proposed new taxes in the EU. Infighting has broken out in Europe, pitting full-service airlines against low-cost competitors. Deutsche Lufthansa AG Chief Executive Officer Carsten Spohr lashed out at discount carriers including Ryanair Holdings Plc, saying cheap fares stoke demand for needless flights that make the industry an easy target for climate campaigners. Discounters, which tend to have more modern fleets, say they shouldn’t be blamed because their jets are generally more fuel-efficient and pack in more passengers, making them less polluting on a per customer basis.

7. Do airlines have a solution?

The industry has a plan, called Corsia, to stabilize aviation’s carbon footprint from 2020 onwards through offsetting. The program aims to compensate for emissions with projects such as tree planting or substituting solar cookers for coal-fired stoves. Participation will be voluntary for countries through 2026, and after that exemptions are likely for vast swathes of Africa and Latin America and some countries in the Middle East. Corsia is backed by the UN’s ICAO. In a critical analysis of the plan, the agency’s observer on climate change said Corsia needs to be broader and tougher to align with the Paris Agreement by including stricter efficiency goals, incorporating sustainable alternative fuels, and addressing the non-carbon climate effects of flights.

8. Is emissions-free flight possible?

Airlines and planemakers are seeking ways to reduce their carbon footprint through new technologies. One promising avenue is the development of synthetic hydrocarbons made from hydrogen and CO2. The process needs huge amounts of renewable power to be carbon neutral. One estimate puts its cost at three to six times more than traditional fuel, which would boost ticket prices. Biofuels are also possible, but quantities are limited and more efficiently used for road transport. Hybrid and electric planes are being developed but won’t make an impact soon. A small seaplane company in British Columbia called Harbour Air made what it says was the first flight of an all-electric commercial plane in late 2019. The six-passenger retrofitted de Havilland flew for about five minutes; its approval by aviation authorities would take years. Airbus SE has said it’s considering producing a hybrid successor to its best-selling single-aisle A320, which seats up to 240 people, but not before 2035.

--With assistance from William Wilkes, Ellen Proper, Ewa Krukowska, Niclas Rolander and Richard Weiss.

To contact the reporter on this story: Tara Patel in Paris at tpatel2@bloomberg.net

To contact the editors responsible for this story: Anthony Palazzo at apalazzo@bloomberg.net, Guy Collins

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