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The Heathrow 13: the climate change argument against runway expansion

The 13 activists who occupied one of Heathrow’s runways in July last year – the so called Heathrow 13 – are going to be sentenced today. Their protest was about the impact of a new runway on climate change and, if given custodial sentences, the Heathrow 13 could become the UK’s first climate change protesters to go to prison.

The CO2 emissions associated with an additional runway, at Heathrow or Gatwick, and the implications for the overall emissions from the UK aviation sector, would pose a significant challenge to the UK’s requirement to reduce emissions.

AEF analysis, and the figures produced by the Airports Commission, have outlined why a new runway would leave aviation CO2 emissions far above the level compatible with the UK’s climate change targets, as demonstrated in our accompanying infographic. See our report: All set for take off? Aviation emissions to soar under Airports Commission’s proposals for more information.

Carbon Brief’s publication of the expert witness statement provided by Professor Alice Bows-Larkin for the court case reinforces the scale of the challenge and argues that a new runway would be at odds with climate ambition, particularly the goals agreed as part of the Paris Agreement.

Noting that emissions from Heathrow Airport already contribute almost 50% of the total CO2 produced by domestic and international flights associated with the UK, the statement goes on to argue that policies to attain temperature based goals, such as the objective from the Paris Agreement to limit temperature rises to 1.5 – 2 degrees, must take the contribution from aviation into account. Prof Bows-Larkin argues that the UK Climate Change Act is currently not stringent enough to deliver the goals of the Paris Agreement, and current policies surrounding the aviation sector in particular are at odds with that agreement. This is particularly so when considering that aviation emissions have historically had a warming impact that is approximately twice that of its carbon dioxide emissions alone (due to the effects of NOx at high altitude and contrails). Emissions from aviation will need to be reduced to near zero in the future in order to keep global warming “well-below 2C above pre-industrial levels”.

Even without taking these issues into account, the Committee on Climate Change’s advice in relation to the UK’s CO2 targets means that other sectors would be required to make emissions cuts of up to 90% to account for aviation emissions. There is limited evidence that this will be achieved and more detail is needed to assess possible mitigation measures suggested by the Airports Commission for CO2 emissions associated with an additional runway.

The issues raised in the AEF’s analysis and in Prof Bows-Larkins statement highlight that airport expansion on the scale envisaged by the Airports Commission is not compatible with the UK target, or any future revisions to take account of the Paris Agreement. Without effective Government policies to reduce emissions, climate change will remain a significant barrier to any decision to proceed with a new runway.


Download: Alice Bows-Larkin witness statement on aviation and climate change

Download AEF report: All set for take off? Aviation emissions to soar under Airports Commission’s proposals

Image credit: Ray Wewerka via Flickr

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