Aviation, decarbonisation and climate change

The aviation industry has been under long-term pressure to decarbonise air travel – from governments, stakeholders and the public. In 2019, aviation accounted for 8% of UK CO₂ emissions – this is made up of emissions from both domestic and international aviation (defined as international flights departing the UK).

The coronavirus pandemic has caused an unprecedented reduction in demand for air travel, but many within aviation industry expect air passenger numbers to recover to 2019 levels by 2023-24. As growth recovers, the challenge of decarbonising aviation remains, and the Committee on Climate Change (CCC, the Government’s independent advisers) say that aviation could be the largest contributor to UK greenhouse gas emissions by 2050. At the 2020 Citizen’s Assembly on Climate Change participants “resoundingly rejected” industry projections for a future in which air passenger numbers would rise by 65% between 2018 and 2050, saying that it would be “counter-productive” for tackling climate change.

In June 2019 the Government amended the Climate Change Act 2008 (CCA) to set a net-zero target for greenhouse gas emissions by 2050. The CCA does not explicitly cover emissions from international aviation and shipping, however these emissions have been taken into account by setting aside “headroom” within the carbon budgets. The CCC has recommended that emissions from the UK’s international aviation be formally included in the net-zero target.

Aviation is widely recognised as both one of the most carbon-intensive forms of transport, and one of the most difficult to decarbonise. The lack of well-established zero or low emission alternatives to conventional fossil fuel-powered flight means that reducing emissions from aircraft will be very difficult in the short to medium term. The aviation industry, perhaps more than any other sector, will rely heavily on market-based measures (i.e. offsetting) to meet climate targets if growth is unconstrained.

The UK Government, the EU and international bodies, and the aviation industry have proposed a number of initiatives by to mitigate emissions from aviation, including:

• Market-based measures such as the United Nations CORSIA program, EU Emissions Trading System (EU ETS) and the future UK ETS;
• Improvements in fuel efficiency in conventional aircraft, changes to air traffic management, airspace modernisation, and ground operations at airports; and
• Changes to fuel use and the introduction of novel aircraft, including the more widespread use of alternative lower carbon aviation fuels (e.g. biofuels) and the limited introduction of electric and hybrid-electric aircraft before 2050.

However, there have also been calls for a reduction in the demand for flying, including through changes in policies (such as taxation) and individual consumer choices.

The Government is in the process of revising transport policy across all modes in order to meet the challenge of the 2050 net-zero emissions target. The Government intends to publish a transport decarbonisation plan and aviation strategy (including a net-zero aviation strategy) in due course, and probably before the UN Climate Change conference, COP 26 (1–12 November 2021), hosted in Glasgow. The Government previously said that the “policy and legislation programme for this environmental super-year will culminate in the UK hosting … COP 26”.

More information on climate change policies and aviation can be found on the Commons Library website.