If you're wondering whether a third runway at Heathrow is a good idea, the Department for Transport has helpfully run the numbers. The answer is no. The cost to the nation's wealth will be somewhere between £23.4bn and £62.5bn. These are not the fevered calculations of environmental activists; they come from the government's own transport department.

For decades, ministers have insisted airport expansion is essential for "growth." As chancellor, Rachel Reeves claimed a third runway would add 0.43% to GDP - a figure later revealed to come from a report commissioned by the airport itself. The transport department's independent analysis put the real GDP boost at 0.03% to 0.05%, which is eight to 14 times less than Reeves' claim. Against that modest gain, the department weighed the social and environmental costs and found a massive net loss.

The same analysis concluded that a third runway would cause major harm to the health and wellbeing of up to 3 million local people. So, to summarise: a project that could cost up to £62.5bn, deliver a GDP bump of as little as 0.03%, and make 3 million people sicker is being sold as progress. George Monbiot is a Guardian columnist, and even he might struggle to be this bleak. If we are to prioritise human life over short-term "growth," we need to use planes less, not more - and maybe stop commissioning reports from the people who want to build the runway.