UTRECHT, Netherlands -- Brussels resident Nour Ghallale-Massa says she had long considered herself a conscious consumer: she was vegan, bought most things she needed secondhand and limited her plastic waste. But it was not until she saw an online posting by a friend that showed the carbon dioxide emissions of plane flights that she decided to change another part of her lifestyle.
"I was a traveling nomad for a while, taking a lot of cheap flights," she says. "And then I saw it in black and white: one flight to Bali equals four years of my total allowable annual CO2 footprint. As soon as I understood the amount of harm I was causing, it felt very hypocritical to still call myself a sustainable person. I haven't flown since."
People such as Ghallale-Massa inspired activist Maja Rosén to expand her campaign to reduce traveling by air beyond her native Sweden. Last year, Rosén persuaded 14,500 Swedes to take a year off flying. The Nordic country has since recorded fewer flight bookings and more rail bookings on both private and business trips. "Flygskam," or "flight shame" has become a buzzword, particularly among younger travelers.
As soon as Rosén translated her original blog into English, she says she started receiving emails from concerned individuals around the world, eager to bring the campaign to their country. Beyond Sweden, the United Kingdom, Denmark, Belgium, France and Germany now have local versions of the campaign.
The expanding campaigns stem from growing public worries about the effects of climate change -- one international survey ranks climate change alongside terrorism as the greatest threat to global security. Those concerns are especially strong in Europe, but questions remain about how effective campaigns to reduce air travel can be, especially for people living in large countries separated by oceans, such as the United States, Canada and Australia.
The flight reduction campaigns are also a reaction to an increase in air travel worldwide, particularly in Asia. Roughly 4.1 billion passengers took to the skies in 2017, according to the International Air Transport Association, a trade association for the world's airlines. The organization projects that number to double to 8.2 billion by 2037.
Kimberly Nicholas, a senior lecturer in sustainability science at Lund University in Sweden, acknowledges that reducing air travel worldwide will require drastic political measures, as well as changes in individual lifestyles. Nicholas, who has produced research that shows reducing flying is one of the most effective ways people can reduce their carbon footprint, says government policy would be needed to reduce air travel.
"We know that the greatest reduction in smoking came from price increases, much more than banning advertising or smoking in public places. In order to cut flight emissions to the levels necessary to stay below the IPCC's limit of 1.5 degrees planetary warming, governments globally will need to stop subsidizing flying."
Policies are being enacted across Europe that target air travel. Earlier in July, the French government announced that beginning in 2020 an "eco-tax" will be placed on plane tickets. Sweden introduced such a tax in 2018. The Dutch had a similar tax, but it was canceled after one year in 2009 following pressure from Dutch airport executives. An eco-tax will now be implemented in the Netherlands in 2021. With renewed public and political support, the Dutch government is now lobbying for a European Union-wide tax.
Meanwhile, a European-wide citizen petition asking for the same has gained almost 40,000 signatures. Even the airline industry is re-examining the impact of plane travel: The Dutch airline KLM announced in June a campaign that asks the public to reduce air travel.
Europe may have the advantage of many countries being in close proximity, but Canadian Nathalie Laplante says she is committed to ending air travel for her family. Laplante says launching the Canada chapter of the Flight Free 2020 campaign last month gave her the courage to voice concerns over air travel.
"Our kids are 2, 5 and 8 and they have never flown. We used to live near Montreal airport, where they would watch planes fly over really low. Of course, they are intrigued, but they don't mind. Friends might go to Walt Disney, we say: we watch the movies instead and discover the amazing places near us."
Anna Hughes, who collected more than 2,100 pledges so far in the U.K., says travelers can use their purchasing power to drive demand. "Whether we get to 100,000 signatures or not, we hope that the act of signing up and thinking about it will feed into long-term behavior change."
Danielle Batist is a Netherlands-based journalist. You can follow her on Twitter here.