Advertisement

The death of Heathrow’s third runway sends a clear message ahead of Cop26

<span>Photograph: Simon Dawson/Reuters</span>
Photograph: Simon Dawson/Reuters

By some strange quirk of fate, it is exactly 12 years to the day since I, alongside fellow climate activists, climbed on to the roof of the House of Commons to protest against plans for a third runway at Heathrow. Today’s high court judgment is a vindication of everything climate activists have been saying for more than a decade: Britain cannot honour its national commitment to tackle climate change at the same time as building a new runway at one of the busiest airports in the world.

To be precise, the court did not quite say this. It ruled that ministers’ failure to take the UK’s climate change commitments into account rendered the Airports National Policy Statement (ANPS) – which effectively gave the green light to a third runway – unlawful. In order to be lawful, the ANPS would have to be rewritten to include a credible plan for squaring expansion with our commitment under the Paris Agreement to seek to limit global temperature rise to no more than 1.5C. The court was careful to clarify that it has no opinion on whether or not this is possible.

Related: A third runway for Heathrow is no way to ‘level up’ Britain | Justine Greening

As someone who has been fighting these plans for 15 years I can confirm that it isn’t. If the third runway is built, there are only three possible outcomes: either we will fail on climate change; or we will have to constrain capacity elsewhere, roughly equivalent to closing Manchester airport; or we simply won’t be able to use the new runway at Heathrow, making it one of the most expensive white elephants in history.

It is difficult to overstate the significance of this decision. Heathrow airport is a bastion of the global fossil fuel economy, so the symbolism alone of this defeat will resonate loudly around the world, giving courage to the movement fighting for a livable future – while striking fear in the hearts of the corporate fossil interests still determined to profit while the planet burns. It also sends a clear and timely message in advance of the UK hosting the most important UN climate summit since Paris, Cop26: Britain is prepared to lead the world in tackling the climate crisis. Scrapping Heathrow expansion is a surprise gift to climate diplomacy.

But the mechanics of this decision could be even more important for the climate struggle. A British court has ruled, quite sensibly, that domestic policy decisions must be assessed against their impact on the UK’s ability to fulfil commitments under the Paris Agreement. The British judicial system remains incredibly influential globally, with courts around the world modelled on our own, so this means any high-carbon infrastructure project – from motorways to fracking wells to coal-fired power plants – could potentially now be blocked as unlawful in any of the 195 countries that are signatories to the Paris Agreement.

So what happens next? Well, the airport will appeal, but it will lose – because the argument is unwinnable. Expanding Heathrow will have no positive impact on the UK’s economy. Pressure to expand Heathrow has nothing to do with increasing the number of international business flights, which are in sustained decline across all of London’s airports. In reality, the industry’s push for expansion is overwhelmingly about handling ever more international transfer passengers, alongside more and more outbound leisure flights by wealthy frequent flyers from London and the south-east. These are all journeys that cost the UK money rather than bringing it in. My own suspicion is that it may not even get as far as an appeal, as Heathrow’s investors will now get cold feet and find excuses to withdraw from the project. The third runway is dead, and cannot be resuscitated.

More widely, today’s judgment marks a turning point in the climate struggle. It looks like the beginning of the British state taking the implications of the climate emergency as seriously as its citizens have now begun to. For UK air travel, this means there is turbulence ahead. We can no longer muddle on with the pretence that ever-increasing demand for flights can be met while also reducing emissions down to zero. The uniquely generous tax breaks that have kept air travel artificially cheap must end, but if the climate movement wants to maintain the support of the wider public, we must do this in the fairest way possible. That means bringing in a frequent flyer levy, which would protect access to some air travel for all, regardless of income, while still keeping aviation emissions within safe limits for the climate. Whether Boris Johnson’s government has the stomach for this kind of medicine remains to be seen.

• Leo Murray is a co-founder and director at climate charity Possible