In 2019 alone, 57.6 million tonnes of cargo and 4.5 billion of passengers were flown around the world facilitating development of business relationships, reunification of families and the general supply of consumer goods. At the same time global commercial aviation emitted 918 million metric tons of CO2 representing 2.8% of global CO2 emissions. With its important role in global transport, it comes as no surprise that decarbonisation of aviation sector was a key theme of the Transport day at COP26 international climate change talks in Glasgow.

COP26 marked the launch of the International Aviation Climate Ambition Coalition (IACAC) with 23 nations collectively responsible for more than 40% of global aviation emissions pledging sector-specific 1.5C goals, through cooperative efforts to increase investment into sustainable aviation fuel (SAFs), and low-carbon and low-emission aircraft technology. As part of advancing its own net zero commitment, the UK has incorporated aviation into the country’s Sixth Carbon Budget and committed £180 million investment to the development and use of SAFs. Earlier this year, for example, British Airways flew its first carbon-neutral flight from London to Glasgow using a blend of 35% sustainable aviation fuel, which reduced emissions by 62% compared to the same route one decade ago.

However, despite these global, national and commercial efforts, decarbonisation of aviation sector is not a simple task. At the UK Presidency Pavilion’s event Delivering Jet Zero, held as part of COP26, panel speakers from the ZeroAvia, LanzaTech and Heathrow Airport emphasised that historically energy transitions – from coal to oil, oil to gas and so on – took on average 50 years. Against this context, the challenge of the next 30 years should be openly acknowledged.

Anticipating this challenge, the International Civil Aviation Organisation established the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) in 2016, the world’s first global, sectoral and market-based carbon offsetting scheme. The pilot scheme came into effect in January 2021 and, subject to continued positive development and feedback, ICAO will meet in September 2022 to map out the next stage of long-term development in order to meet the global aviation industry’s net zero target.

As designed, CORSIA will provide a vital short-term measure whilst the industry develops and deploys decarbonisation technologies at scale. However, as the speaker at the Blue Zone event Delivering Jet Zero were quick to emphasise, offsetting should also not be heralded as panacea, but rather as a strategy that allows for continuous development of zero-emissions technology. In its decarbonisation, aviation sector needs to have a clear plan to phase or cap its reliance on offsets, which should be seen as complementary to primary efforts to reach net zero aviation by mid-century.