Many of us feel guilty about flying because it is a very obvious source of CO2 emissions. Aviation causes around 2.5% of global greenhouse gas emissions. But when we walk into a new building, we may not feel the same sense of guilt, even if global concrete production is closer to 8%. Or when we get into a petrol car or turn on our gas central heating.
This is because aviation is a clearly visible symbol of our carbon-intensive consumption and the aviation industry has so far been slow to address the climate protection agenda. According to the United Nations, we expect global warming of up to just over 3°C, which would be catastrophic for the planet and our societies.
Human-caused global warming has just passed 1.5°C. However, science suggests that we could keep this temperature rise close if we reduced global emissions by 45% by 2030 and reached net zero by 2050.
Following the COVID-19 crisis, aviation continues to regroup and grow and is expected to be a trillion-dollar industry by 2030, but is incredibly vulnerable to the impacts of climate change. Clear air turbulence in the North Atlantic has increased by 55% since 1979, and significant incidents have resulted in deaths, serious injuries and damage to aircraft.
Extreme weather events are not limited to this region: extreme rainfall and flooding are affecting airports in the Middle East, while snowfall is crippling airports in the UK and causing significant disruption.
While aviation makes a relatively small contribution to global emissions, the industry is forecast to grow at 4% per year for the foreseeable future. Without sensible measures, net zero will never be achieved by 2050. The introduction of new generations of technology is not yet proven or feasible, and aviation must reduce its carbon footprint now.
These five key steps not only focus on decarbonization, but make aviation more sustainable while improving operational efficiency and safety.
1. Optimize flight planning and airspace
Airlines are already trying to select the most fuel-efficient routes and altitudes using advanced flight planning systems, AI and optimization software. However, future route optimizations could reduce turbulence and the formation of contrails with the associated radiative forcing, increase comfort and safety for passengers and make a positive contribution to the environment.
By optimizing aircraft separation and air traffic control flow management, aircraft crowding and arrival delays can be avoided as aircraft are forced into holding patterns, waiting their turn to land at the airport, and carrying and burning large amounts of fuel in the process.
Eduardo Frederiksen/Shutterstock
2. Make operations more sustainable
The latest generation of commercial aircraft uses advanced aerodynamics and engine technology, saving a significant amount of fuel and emissions compared to previous types.
Airlines will need to invest in modern, fuel-efficient aircraft as they continue to develop their expansion plans. In the meantime, they can retrofit existing aircraft to improve efficiency by adding winglets to reduce induced drag and introduce new aircraft cabins that save weight and thus improve efficiency.
Airlines and airports can also optimize weight and center of gravity by reviewing the distribution of cargo and passengers to maximize efficiency, as well as using renewable energy to replace auxiliary equipment on the ground and improve noise and air quality.
3. Switch to sustainable fuels
The largest source of emissions in the aviation industry remains the combustion of kerosene. Airlines must transition from conventional to sustainable aviation fuels (SAF) within an agreed timeframe and with equal access. SAFs cover a range of technologies, from biofuels made from plants, animals or waste to synthetic fuels such as synthetic kerosene.
Depending on what type of SAF is used, they could reduce CO₂ emissions by 20-98% compared to conventional fuel. The quality, reliability and supply of SAFs must be ensured and secured.
4. Make airports more environmentally friendly
Airports can become much more sustainable by using renewable energy such as solar or wind energy to power airport operations, including powering terminals and equipment. Renewable energy can be used for ground equipment and aircraft support, such as electric aircraft tugs, baggage handlers and catering trucks.
It is possible to improve ground operations to reduce emissions, e.g. B. by minimizing idle time of aircraft engines during taxiing and using reduced engines for taxiing around the airport.
The industry has an exciting opportunity to design and develop the next generation of sustainable airports. There are 575 existing or new airport projects worldwide with a total value of $488 billion (£395 billion), with many more planned over the next two decades.
5. Smart Travel
The aviation industry can make passengers more sustainable by redefining the door-to-door passenger experience, not just the time they spend at the airport or on the plane. This may include luggage collection at your home and incentives to use public transport to the airport.
Help to reduce luggage weight can be achieved by providing basic items (e.g. toiletries) or heavier equipment such as skis, ski helmets and golf clubs at the destination, rather than requiring everyone to pack them.
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