Carbon pollution from private jets has soared in the past five years, with most of those small planes spewing more heat-trapping carbon dioxide in about two hours of flying than the average person does in about a year, a new study finds.

About a quarter million of the super wealthy — worth a total of $31 trillion — last year emitted 17.2 million tons (15.6 million metric tons) of carbon dioxide flying in private jets, according to Thursday's study in the Nature journal Communications Earth & Environment. That's about the same amount as the 67 million people who live in Tanzania,

Private jet emissions jumped 46% from 2019 to 2023, according to the European research team that calculated those figures by examining more than 18.6 million flights of about 26,000 airplanes over five years.

Only 1.8% of the carbon pollution from aviation is spewed by private jets and aviation as a whole is responsible for about 4% of the human-caused heat-trapping gases, the study said.

It may seem like a small amount, but it's a matter of fairness and priorities, said the study's lead author, Stefan Gossling, a transportation researcher at the business school of Sweden's Linnaeus University.

"The damage is done by those with a lot of money and the cost is borne by those with very little money," Gossling said.

The highest emitting private jet user that the team tracked — but did not identify by name — spewed 2,645 tons (2,400 metric tons) of carbon dioxide in plane use, Gossling said. That's more than 500 times the global per person average of either 5.2 tons (4.7 metric tons) that the World Bank calculates or the 4.7 tons (4.3 metric tons) that the International Energy Agency figures and Gossling cites.

"This report presents further proof that billionaires are causing the climate crisis," said Jonathan Westin, executive director of the advocacy organization Climate Organizing Hub. "They are clinging to their private jets and oil profits while regular people see increasing floods, hurricanes and wildfires."

Earlier this year the International Energy Agency calculated that the world's top 1% of super-emitting people had carbon footprints more than 1,000 times bigger than the globe's poorest 1%.

Gossling's study counted more than 35,600 tons (32,300 metric tons) of carbon pollution from just five global events — 2022's World Cup in Qatar, 2023's World Economic Forum, 2023's Super Bowl, the 2023 Cannes film festival and the 2023 United Nations climate negotiations in Dubai. That came from 3,500 private jet flights.

"It's a grim joke that the billionaire class is flying private jets to the annual climate conferences, and the United Nations should crack down on this hypocritical practice," said Jean Su, energy justice director for the Center for Biological Diversity.

Researchers also examined more than 1,200 flights by celebrity actors, singers and directors, but Gossling declined to give the public figures' names.

Many private flights aren't even for business "nor are they necessary," Gossling said. "They are very often lifestyle related."

While the study "does shine a bright light on some of the most gluttonous emitters, i.e. the very wealthy," University of Pennsylvania climate scientist Michael Mann said the focus shouldn't be on individual behaviors and someone's carbon footprint. He called that "a distraction from the primary task at hand, which is decarbonizing our societal infrastructure through systematic change and policy."

That's the problem, Gossling said.

"We have been told for a long time that it is the system that needs to change, not the individual," Gossling said. "That has meant that nobody has been responsible for their lifestyles."

"The problem is that the 26,000 aircraft and the individuals using them will say 'We are just a small group. We are not relevant in terms of emissions.' But everybody else will look at the small group and say, 'Look these are the super-emitters, if they are not relevant, how can we be relevant?" Gossling said. "And then you have this pointing at each other of two different groups that locks us in a circular argument."

About 51% of those private jets burn at least 239 gallons of fuel per hour. That's translates to more carbon emissions in two hours and one minute than the IEA's estimate of the average person's yearly 4.7 tons (4.3 metric tons) of pollutants, the study calculated.

"Given that technology is not going to resolve (climate change), I think the answer is clear. We need to start at the top," Gossling said.

Gossling said the way to address the high-flying emissions is to charge a tax or landing fee equivalent to the damage done by each ton of emissions. That's about $200 or 200 euros. Westin called for a private jet ban.

The United States is by far the hub of private jets with more than 68% of the globe's private aircraft, about 5 per 100,000 people, the study found. But Gossling said private jets are everywhere, even in poor countries.

In the United States, Alaska has the most private jet flights per person, at nearly 5,000 per 100,000 residents, according to a different study by the student travel company Rustic Pathways.

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