Flight shame: flying less plays a small but positive part in tackling climate change

“Flyskam” – the Swedish word for “flight shame” – describes a phenomenon that has taken off around the world, as travellers face growing pressure to reduce their carbon emissions by switching to alternative modes of transport. Climate activists have denounced air travel, settling for boats, trains or, at a pinch, paying to offset the carbon emissions from their flights. Celebrities face criticism for flying by private jet – and Germany’s Green Party has even put forward plans to ban domestic flights within the country.

Yet according to our calculations based on the the BP Statistical Review of World Energy 2019 (which we both contributed to), CO₂ emissions from aviation fuels account for a mere 3% of global CO₂ emissions and 8% of worldwide oil consumption. This may not sound like much, but in the past 30 years, aviation fuel consumption has almost doubled, consistently contributing to the growth in global oil consumption.

To see whether the efforts of individuals to cut down on air travel can make a meaningful difference to global emissions, we took a closer look at how fuel consumption by the aviation industry has changed over time, and what trends are set to take hold in the future.

Fuelling demand

A common way of estimating CO₂ emissions for individual passengers is to take the aircraft type and distance travelled into account. This is the method used by carbon offsetting organisation atmosfair, and the International Civil Aviation Organisation’s carbon footprint calculator.

By contrast, our approach to quantifying CO₂ emissions from flights involves looking at the consumption of aviation fuel. This eliminates the need to rely on estimates of passenger numbers, aircraft type and how full or empty planes are, and can easily be compared to other means of transportation.

An important caveat is that our method ignores the effects of condensation trails or nitrogen oxides (NOx) emitted by planes. Including these in the estimates is challenging because their effects only last for a matter of minutes, hours or days. But research suggests that the warming effects of aviation can be much larger, depending on where in the atmosphere NOx are emitted. So our approach only gives a conservative estimate of the emissions from aviation.

Global growth

A large share of aviation fuels are consumed in developed countries. In 2018 the US alone accounted for more than 20% of aviation fuel consumption. In the same year half of all aviation fuel consumption took place in OECD countries – a club of mostly developed countries which represent about 15% of world population.

Future efficiency

Since 2000 the number of air passengers has almost tripled, reaching a new high of 4.3 billion in 2018. The main driver of growth is budget airlines, which offer primarily short and medium-haul flights in the American and European markets.

A greener alternative

Low-carbon sustainable aviation fuels can reduce CO₂ emissions, although only six airports in the world (Bergen, Brisbane, Los Angeles, Oslo, San Francisco and Stockholm) offer them on a regular basis. The International Energy Agency (IEA) estimates that, in 2018, sustainable aviation fuels only accounted for 0.1% of aviation fuel production – so much more could be done to promote their use around the world.