It's Down to Us to Reduce the Carbon Footprint of Flying
Millions of people around the world are reducing their carbon footprint to slow down global heating by changing what they eat, what they buy and how they travel. And with the growing awareness of “flygskam” (Swedish word meaning “flight shame”), the contribution of air travel to global heating is coming under increasing scrutiny.
As air travel continues to grow at a significant rate, it is tempting to think that technological breakthroughs will solve the problem and help us feel less guilty sitting in the window seat. But any technology that could significantly reduce the carbon footprint of airlines is way off in the future and we need to start making a major difference now.
While it is difficult to get a meal on a flight these days, our appetite for flying is growing. There were 4.3 billion air travellers in 2018 — 38 million more than the year before — and that number is expected to almost double to 8.2 billion by 2037. To meet this demand, the number of aircraft is expected to increase from 20,000 planes today to 50,000 by 2040. And, they’re expected to fly more often.
While the airline industry says it contributes only 2% of global GHG emissions, because gases such as nitrogen oxides are emitted at high altitude, these gases actually trap more heat and the Climate Action Network calculates the industry is responsible for 5% of emissions. And on a relative basis, air travel has a big footprint compared with other forms of transportation. According to the European Environment Agency, the carbon footprint of flying is 285 grams of CO2 per kilometre while car travel and rail are 104 and 14 grams per kilometre, respectively.
Airliners have become lighter using new materials in a bid to improve fuel economy but these measures are getting closer to maximum efficiency. Concepts for reducing carbon emissions centre on new fuels or new power sources, but there are major challenges with both.
One solution is to mix biofuels with kerosene, the current jet fuel. But biofuels are expensive and come at an environmental cost. They make up 6% of the global harvest, generate significant GHG emissions during production, and use valuable cropland for fuel instead of food — although, new biofuels made from bacteria and/or food waste offer more potential to reduce emissions. Liquified hydrogen and LNG are possible alternate fuels but they are four to six times the volume of kerosene for a similar power output.
Electric motors could power planes in the future but current battery technology makes this option far too heavy for current aircraft design. Conventional jets take off heavy with a full load of fuel, and land light once most of the fuel is consumed. Batteries would have the same weight during takeoff and landing, requiring a redesign of landing gear systems and air frames. These potential solutions are at least 20 years in the future. Streamlined air traffic control systems could improve efficiency by 10 percent but even this requires expensive overhauls of current systems which will take years to implement.
So, we will have to rely on behavioural change rather than technology to solve this one quickly.
Swedish activist Greta Thunberg, is setting the example by travelling around Europe by train instead of flying and European train travel is booming as a result. European governments are considering green taxes on air travel to try to change consumer behaviour. Even the Dutch airline, KLM, is encouraging people to fly less as part of their “Fly Responsibly” program. While Canadian academics recently announced that they would reduce the number of flights taken to attend conferences.
Flying is largely a discretionary item. Long haul flights for a weekend getaway will become a thing of the past given the vastly reduced carbon budgets we all need to live within to slow down global heating. Some estimates say that to meet the climate goals of the Paris Agreement, we will need to limit our carbon emissions to less than two tonnes per year – the equivalent of a single return trans-Atlantic flight.
So, we all need to consider flying less, taking other forms of transport, vacationing closer to home and making greater use of technology to connect with people. By doing so, we can reduce our carbon footprint and we won’t have any hassles from airport security.