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Challenging airport expansion

In 2019 the requirement for the UK to achieve net zero emissions by 2050 (with all emissions by that date needing to be balanced by greenhouse gas removals) became law. In December 2020, the Government’s expert climate advisory body, the CCC, set out its recommendations both on the level of the sixth carbon budget (covering years 2033-37) to deliver the 2050 target, and on what steps are needed more generally for all sectors to be on a pathway to net zero.

The CCC’s advice for aviation included recommendations on how these emissions should be accounted for as well as on the need to set targets for CO2 and non-CO2 and to limit demand growth. Since the maximum level of passenger demand that could be compatible with achieving net zero aviation emissions can already be accommodated with existing runways and terminal capacity, the CCC recommended no net increase in the UK’s airport capacity.

Many UK airports, prior to the COVID-19 pandemic, had big plans for growth however, and a surprisingly large number are continuing to pursue them even after huge reductions in traffic, and forecasts of a recovery that could take years. Some had already submitted applications which were at various stages of the decision-making process, and others had future plans to increase capacity. 

Heathrow, responsible for around half the total emissions of the UK aviation sector, won the latest stage of a legal battle over its expansion proposals in December last year, with the Supreme Court overturning an earlier ruling that the Government’s plan for a third runway at the airport was unlawful because it had failed to take into account the Paris Agreement on climate change. Whether or not Heathrow expansion in fact proceeds, many other airports are actively pursuing their growth plans and while smaller in scale the cumulative effect of these proposals on climate change, would, if they were all approved, be significant.

The industry’s Sustainable Aviation roadmap, published in February 2020, weeks before the crisis brought flights to a halt, forecast that combined growth plans of UK airports will result in a 70% increase in passenger numbers on today’s level. This is nearly three times the 25% growth allowed for in the Committee on Climate Change’s net zero modelling. Our analysis shows that if all airport expansions are allowed to proceed it could result in an extra 9MtCO2 per annum by 2050.

Combined growth plans of UK airports will result in a 70% increase in passenger numbers on today’s level. This is nearly three times the 25% growth allowed for in the Committee on Climate Change’s net zero modelling.

Unrestricted growth in aviation will outpace technological improvements in terms of both emissions and noise, if the industry resumes the growth trajectory forecast prior to the coronavirus pandemic. A moratorium on future airport expansion would be one of the more straightforward policy measures for the Government to put in place, as a first step towards bringing aviation’s environmental impacts to within acceptable levels.

Some local councils, meanwhile, are grappling with airport planning applications, in the context declared climate emergencies, or ambitious local CO2 targets. Although the airports are appealing their respective decisions, applications for expansion at both Bristol and Stansted have been turned down by local authorities on the basis, at least in part, of their likely impacts on climate change.

Click here for an update on current airport expansions, as well as new and existing airport planning applications.

What do we want to see?

  • The Government should drop its support for Heathrow expansion, and should declare the Airports NPS to be invalid given the changes to climate change legislation since it was adopted in 2018.
  • A moratorium on all other airport expansion plans should be introduced (until and unless these can be shown to be compatible with the UK’s net zero plans).
  • Local and regional authorities should be both encouraged and empowered to consider the impact of airport expansion on local climate change targets.