To be clear, I am not advocating that people should not fly. But I am advocating that people who fly a lot ought to fly less. If we assume the USA flight statistics are roughly representative of travelling behaviours in developed societies more generally, this article from the International Council on Clean Transportation from September 2019 might be of interest to people living in developed countries : "To determine if the average American should be ashamed to fly, you must determine what constitutes “average”. The results of a 2017 IPSOS survey of American travelers, summarized in the graphic below, backs up the contention that, for the average American, flying actually isn’t actually a big part of their carbon footprint. Share of airplane trips by U.S. adults As shown in the graphic, American adults can be divided up into three groups. About one-half (53%) of those didn’t fly in 2017. Another one-third (35%) flew 1 to 5 times per year and are responsible for about one-third of all flights. The remaining minority of Americans –12% to be exact – who fly six or more times per year were responsible for about two-thirds of all flights in 2018. That’s an average of 14 flights per person. How does that translate to CO2 emissions? The IPSOS study doesn’t break down exactly which trips – domestic vs. international, economy vs. business class – these frequent fliers take. But we can get a ballpark sense of how these trips translate to emissions by randomly assigning trips to individuals in proportion to how often they fly. (This approach likely undercounts the carbon footprint of frequent fliers, who are more likely to fly carbon-intensive business class, so we’re erring on the side of being conservative.) The table below breaks down U.S. aviation CO2 emissions by trip frequency. Group Trips per year (2017) Percent of American adults Percent of all trips Aviation CO2 per person Non-fliers 0 53% 0% 0 tonnes Occasional fliers 1 or 2 21% 13% 0.33 tonnes Infrequent fliers 3 to 5 14% 19% 0.83 tonnes Frequent fliers 6+ 12% 68% 3.1 tonnes So, the answer to “should Americans concerned about climate change be ashamed of flying?” is an equivocal “probably not*”. Not because per capita emissions aren’t significant, but rather because the average American doesn’t fly that often. If you randomly choose an American and calculate their aviation carbon footprint, more often than not it would be zero. If you choose someone who flies 5 or fewer times per year, their aviation carbon footprint would only be about 3% of the 16 tonnes of fossil CO2 the average American releases in a year. However, the asterisk, or disclaimer, is needed because if you choose an American adult who is a frequent flier, you get a very different picture. Three tonnes of CO2 per person is substantial, particularly by global standards. If all Americans were frequent fliers, U.S. aviation jet fuel use would increase about sixfold and planes would easily surpass passenger cars as the largest transport source of CO2 in this country. If everyone in the world flew like American frequent fliers, global oil consumption would increase by 150% and CO2 emissions from fossil fuel use by more than 60%. This would make it impossible to meet international goals to avoid the worst impacts on climate change. So, although aviation dominates the carbon footprint of a relatively small number of frequent fliers, it’s wrong to conclude that trying to convince travelers to reduce a “minuscule” amount of CO2 isn’t worthwhile. Our global climate literally cannot tolerate widespread frequent flying, and people who currently fall into that group probably do need to modify their behavior."