by Sonia Holsen, Summer Intern
Why are we talking about airplanes?
The aviation industry has allowed people to connect with every part of the world in a matter of hours; it has brought people and cultures together from opposite poles; it has allowed us to feel closer to our families and friends even if we are countries away; it has allowed us to share materials and resources across the globe, and so much more.
Flying is by far the fastest form of transportation, but that doesn’t necessarily mean it is the most efficient in terms of the environmental footprint and atmospheric impact that it leaves behind. Many climate scientists and activists have turned their attention to aviation as an industry that needs to improve its sustainability efforts in order to curb the effects on the climate.
In the US alone, air travel accounts for 3-4% of the nation’s total greenhouse gas (GHG) emissions from all sectors. This may seem like a relatively small portion but GHGs from airplanes pose a particular atmospheric threat due to the altitude at which they are emitted. The exhaust from aircraft engines is made up of ~70% CO2 and ~30% water vapor, two of the most impactful GHGs in terms of accelerating the greenhouse effect.
Airplanes are not the only sources in the aviation industry that are contributing to emissions. When approaching this sector, we must consider the large amount of on-ground-vehicles, airport machines, and airport services that airlines provide for travelers that use energy and emit GHGs to support flying. When we add in emissions from these support services and include the growth the industry is expected to show, it is believed it will account for a quarter of ALL global CO2 emissions by 2050.
The climate effects of aviation are also considered to be an issue of equity and environmental justice. It has been calculated that 1% of frequent fliers are responsible for over half of aviation’s carbon emissions, yet only 3% of the global population is taking regular flights. Check out some more climate aviation facts here.
Sustainability initiatives growing within airlines
Airlines are beginning to recognize the impact of their GHG emissions and are taking action and researching opportunities to lower their environmental impact.
Changes in jet fuel
Experts are finding new ways to produce jet fuels that are more sustainable, are not reliant on crude oil, and produce less greenhouse gases, like carbon dioxide, when burned.
Many different forms of biomass that would otherwise be classified as waste, including used diapers and plants, are being researched as alternative fuel sources and could significantly reduce the GHG emissions of airplanes.
We have to keep in mind that burning any fuel material, even if it is sustainably made and isn’t oil-based, will still release a certain amount of CO2. Experts have deduced that using more sustainable fuels would reduce carbon emissions from the aviation industry by 30-50%.
Electrification
As we are seeing more and more electric vehicles, the same technology is being slowly introduced in aircraft vehicles. Electrification of aircraft would eliminate the need for gasoline and petroleum based fuels that release the most CO2 and other GHGs when used. The electricity used in them could be sourced from renewable energy sources such as solar, wind, and geothermal energy.
There are some airlines that are workshopping electric airplanes for small aircraft doing short flights, and so far it has been working well. Unfortunately, experts say that electrification simply isn’t powerful enough yet to support larger, heavier aircraft that are flying longer distances. Meaning, most of the flights going out of the larger, international airports, and the aircraft that emit the most, couldn’t go electric soon.
Market-based solutions: Carbon tax and carbon offsets
Imposing a tax on carbon emissions within the aviation industry could make these alternative fuels more competitive against conventional fuels and would encourage airlines to use them.
A carbon offset allows individuals or companies to pay a fee that goes directly to another individual or company who has committed to use the money to take steps to reduce carbon and GHG emissions within their field or sector.
Improving mapping and data-collection technology to improve efficiency
Research has found that a majority of non-carbon emissions from planes are released in the contrails of the aircraft, which are created when planes fly in narrow atmospheric bands where the weather is cold and humid. Pilots could avoid these sections of the atmosphere by using accurate, multi-date weather forecasts.
A program called NextGen by the US Federal Aviation Administration uses AI technology to make flights more efficient by reducing idle-time at airports, on the tarmac, or circling above an airport to burn fuel.
There is also a new technology called Sky Breathe that harnesses the power of AI to read big data and analyze billions of records in an effort to save fuel. Sky Breathe claims to have reduced CO2 emissions by 590,000 tons in 2019.
What can YOU do?
There are ways that you as a traveller can lower your own carbon footprint and to help draw back the GHG emissions created by the aviation industry. This is by no means an exhaustive list but provides ideas and resources to help you become a more climate-conscious traveller.
Choose an alternative form of transportation and avoid flying altogether
- Trains have been identified as one of the cleanest forms of transportation as advances in technology have found efficient and more sustainable ways to power high-speed, long-distance trains. Taking a train emits about 84% less CO2 emissions per passenger than would a flight of the same distance.
- If we use energy intensity (the amount of energy consumed to transport one passenger one mile) as a metric to compare GHG emissions between forms of transportation, rail transportation has the lowest energy intensity per passenger.
If you can’t avoid flying, you can make smarter decisions about how you fly
- Educate yourself: Research which airlines are improving their sustainability efforts, and which flights for your route are using the most fuel-efficient aircrafts. German non-profit Atmosfair has created an index that allows customers to compare all of the different airlines in the world and which will have the lowest carbon footprint for a certain distance flight. Check it out the next time you need to fly.
- Choose to fly ‘medium’ sized planes: Both very small (private) and very large (commercial) airplanes are less fuel efficient than ‘medium’ sized airplanes. Small airplanes use a disproportionately large amount of fuel per passenger, and large airplanes require significantly more fuel because of the size of the aircraft and the amount of additional engines it requires.
For those of us who are frequent flyers for vacation and work, flying makes up the majority of our carbon footprint. Being aware of the impact and taking step to reduce those emissions is within reach, and will make the next trip you do decide to fly feel that much more remarkable.