Born in Sweden, the movement to discourage taking planes for environmental reasons has spread to travelers far and wide.

One in five Western travellers is flying less, as “flight shaming” propels people to shun air travel for the sake of the planet – according to a survey of 6,000 Americans and Europeans by Swiss bank UBS.

The survey predicted environmental concerns would keep denting air traffic, as activists such as Sweden‘s Greta Thunberg lead the way and turn people off planes.

Emma Kemp, 25, a campaigner and fundraising manager at United Kingdom climate change charity 10:10, said she skipped flying for her last tourist trip to Italy and Croatia and opted to get around by bus, train and ferry instead.

“I felt I was really travelling,” she told the Thomson Reuters Foundation. “And I felt at peace with myself, having done something for the planet.”

If these trends continue, the expected growth in passenger numbers could be halved, UBS said in a report published this week.

UBS’s July-August survey showed that, on average, about 20 percent of travellers in the United States, France, Germany and the UK had cut air travel by at least one flight in the past year because of concerns about climate change.

Commercial flying accounts for about two percent of global carbon emissions and about 12 percent of transport emissions, according to the Air Transport Action Group, an aviation industry group.

The survey also found that the percentage of people thinking of reducing their flying for the same reason had climbed to 27 percent, up from 20 percent in a previous survey during May 2019.

“With the pace of the climate change debate, we think it is fair to assume that these trends are likely to continue in developed markets,” wrote UBS analyst Celine Fornaro.

UBS said it expects the number of flights in the European Union will increase by just 1.5 percent per year, which is half the rate predicted by plane manufacturer Airbus.

Any cut in air travel will hit air manufacturers hard, with new plane orders at risk if travellers increasingly turn to trains and boats to take trips with a cleaner conscience.

‘Elephant in the room’

In August, 16-year-old Thunberg – an icon for young environmental protesters – crossed the Atlantic in a racing yacht with no shower or toilet to join protests in the US and take part in the United Nations Climate Action Summit.

Thunberg said the voyage cut her own carbon footprint and “sends a signal to other people around you that the climate crisis is a real thing”.

Teen activist Greta Thunberg (centre, in collared shirt) takes part in a climate strike march in Montreal, Quebec [Andrej Ivanov/Reuters]

Her country, Sweden, has led a movement that rests on the idea that travelling on kerosene-guzzling jets is shameful.

It was also responsible for the Swedish concept of “flygskam”- exported as “flight shaming” in English and trending as “avihonte” on French social media.

Scandinavian airline SAS has seen passenger traffic shrink two percent this year, while Sweden’s airport operator said it handled nine percent fewer passengers for domestic flights this year than in 2018. Both have blamed “flight shame”.

Companies such as Klarna Bank AB are cutting back on business flights. The Swedish bank has banned all employee air travel within Europe and discourages long-haul flights.

The anti-flying movement – which emerged in 2017 after singer Staffan Lindberg pledged to give up flying – has now spread well beyond its native Sweden.

Germany has announced plans to cut taxes for train journeys and boost fees for flights. And as world leaders met in New York City for the UN Climate Action Summit last month, delegates were quick to quiz each other on how they travelled as “flight shame” reached peak attention.

“If there’s an elephant in the room … of course it’s aviation,” Norway‘s Minister of Climate and Environment Ola Elvestuen told the summit.