Aviation and Climate Change

  • Laurel Besco

In just over a century, flying has gone from being a remarkable achievement to something done by only the elite to a commonplace form of transportation for travelers and goods. This change and subsequent growth in flying has been largely spurred by technological innovation, as aircraft evolved from the first prototypes to propeller planes and finally to jet planes capable of flying more than halfway around the world without stopping. At the same time, economies have grown, people have more disposable income, the price of flights has come down, and the desire to travel (for leisure, business, or to visit friends and family) has increased. Now, each day, millions of people travel by air,1 and 657 million packages are transported by plane.2

Over a similar timeframe, the world has begun to realize the impact that humanity is having on the environment, and the seriousness of climate change. Since the landmark Paris Agreement was signed in 2015, there has been a renewed urgency for action to reduce greenhouse gas (GHG) emissions across all sectors of the economy and in all countries of the world. Somewhat surprisingly, the aviation sector has not been well recognized in these plans for emissions reductions, despite the fact it is a large and growing source of emissions, currently representing two percent of global GHG emissions,3 (more than the entire Canadian contribution). While emissions from domestic flights—those which depart and arrive in the same country—are reported as part of annual emissions accounts, international emissions are reported separately and not tied to any one country. Who is responsible? Which laws apply? This uncertainty in who must account for and reduce international aviation emissions is largely tied to the complexity of a sector that crosses jurisdictional boundaries thousands of times a day.

The standard proposals for how to reduce GHG emissions from aviation have included sustainable fuels, technological improvements, operational improvements, and the use of market-based measures.4 There is still great interest in biofuel innovation, technological changes, and operational shifts, but the most recent advancement has been that the international community developed and implemented their own market-based measure, a program named the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA).5 While an important step forward, there are significant questions about the long-term impact of this mechanism on absolute and lasting emission reductions from the sector. The stated goal of CORSIA is carbon-neutral growth beyond 2020, which effectively means the industry could continue to operate and grow exactly as they are so long as they purchase offsets (emission reductions from another source) that are equivalent to what they produce in their flights. Therefore, while this mechanism is a step in the right direction, the challenge remains of how to mitigate emissions in a way which results in absolute reductions from international travel. Further, CORSIA, as its name suggests, only deals with international flights, leaving emissions from domestic flights outside of its scope. This has potentially significant impacts on emission growth, especially in large countries like Canada where a domestic flight might produce more emissions than an international flight in Europe or Asia. While CORSIA has approached the issue of the international nature of emissions in a sensible way—countries are responsible for reporting on how their airlines have offset emissions—the mechanism itself is likely to struggle in moving the sector towards decarbonization unless innovative approaches to offsetting programs are undertaken and clear linkages to domestic policies are made. It is going to take meaningful changes in behaviour, technology, or aircraft fuel (and likely a combination of all three) for real progress to be made in mitigating the impact of aviation on the global climate.



Laurel Besco is an Assistant Professor for the Institute for Management and Innovation, and the Geography Department at the University of Toronto Mississauga. She received her PhD from the University of Ottawa, and previously attended the University of Waterloo for her MA and BES degrees. Her research interests include environmental/sustainability law and policy, green economy, and corporate sustainability.

See Connections ⤴

1↑2↑3↑4↑5↑