Some flying pollution numbers

Why do I harp on flying so much? Doesn’t flying only contribute about two percent to global warming? While measurable, that fraction sounds small. And since everyone flies, doesn’t avoiding flying inconvenience a lot of people for little gain?

The evidence contradicts that view, so time to lose it. Few people fly. If you fly internationally or more than once a year, you’re part of a small elite of a few percent of all humans contributing most of the pollution from flying. Flying is probably your greatest contribution to lowering Earth’s ability to sustain life. (Not included in the paper: when you commit to stopping flying, after the craving passes, you will prefer life.)

At last I found some peer-reviewed numbers on flying in the paper The global scale, distribution and growth of aviation: Implications for climate change by Stefan Gössling and Andreas Humpe. Here are the highlights it reports:

• Investigates air transport demand on global, regional, national and individual scales.
• Estimates that only 2% to 4% of global population flew internationally in 2018.
• Finds that 1% of world population emits 50% of CO₂ from commercial aviation.
• Suggests that emissions from private air travel can amount to 7,500 t CO₂ per year.
• Affirms that current climate policy regime for aviation is inadequate.

From the paper’s abstract: “Data also supports that a minor share of air travelers is responsible for a large share of warming: The percentile of the most frequent fliers—at most 1% of the world population—likely accounts for more than half of the total emissions from passenger air travel.” If you fly internationally or more than once per year, you are in that 1%.

Most people I know fly a few times a year or more. This paper suggests they are mostly in the top one percent, but contribute around half the CO2, just one measure of pollution. If you fly, flying likely contributes you largest share of pollution or close to it. There aren’t billions like you. You’re part of a tiny elite.

One of the paper’s sources quotes the CEO of Boeing: “Boeing CEO: Over 80% of the world has never taken a flight.”

Here’s a telling section:

The world’s “high-emitters”, i.e. individuals contributing disproportionally more to climate change than the “average world citi­zen”, (who emitted close to 5 t CO 2 per capita and year in 2014; World
Bank, 2020a).

Various national studies have confirmed that high emitters are found mostly among the highly affluent. Chancel and Piketty calculate that the top 10% emitters in the world account for 45% of global CO 2 -eq emissions, while the bottom 50% of emitters contributed 13%. In a recent study of consumption in the European Union (EU), Ivanova and Wood find that the top percentile of emitters is responsible for 27% of emis­sions, with the top 1% of emitters exceeding annual per capita emissions of 55 t CO 2 -eq. While high-emitters live in all countries, Chancel and Piketty identify the top 1% of wealthiest individuals in five countries as specifically relevant, with per capita emissions exceeding 200 t CO 2 -eq per year. These high emitters are at home in the USA, with an estimated 3.16 million people exceed average annual emissions of 318 t CO 2 -eq per person; Luxemburg (10,000 individuals emitting 287 t CO 2 -eq/year each); Singapore (50,000 individuals, 251 t CO 2 -eq/year); Saudi Arabia (290,000 individuals, 247 t CO 2 -eq/year); and Canada (350,000 individuals, 204 t CO 2 -eq/year). In comparison, low emitters in many parts of Africa emit a mere 0.1 t CO 2 per year.

It continues about the people who fly most (likely including you if you fly internationally or more than once a year) and people who fly business or first class, who pollute far more:

Surveys suggest that among commercial air travelers, the most frequent 10% of fliers may account for 30–50% of all flights taken. The share of the fuel used by these air travelers is likely higher, as more frequent fliers will more often travel business or first class. For example, The World Bank estimates that 70% of staff travel is on premium classes, which the World Bank estimates to have a three times (business) and nine times (first class) larger carbon footprint than economy class. The energy demand for people to fly in private First Class Suites, as offered by Singapore Airlines or Ethiad, is even greater, with floor spaces of up to 5.8 m 2 per guest (11.6 m 2 per suite; Mainlymiles, 2018). Larger toilets and additional aisle space make it likely that first class suites require significantly more fuel than first class flights. The ICCT (2014) estimates that the carbon footprint of
flying business class, first class, or in a large suite is 5.3, 9.2 or 14.8 times larger than for flying in economy class.