Climate doomsayers keep putting sell-by dates on their credibility

I was slightly surprised when Greta Thunberg announced at Davos that we had eight years left to save the planet. As long as that? Admittedly, that’s four years less than Alexandria Ocasio-Cortez, who put it at 12, although, come to think of it, that was last January, so presumably she now thinks we’ve got 11 years left. But some doomsayers have been much less optimistic. According to Peter Wadhams, a Cambridge professor interviewed in the Guardian in 2013, Arctic ice would disappear by 2015 if we didn’t mend our ways, while Gordon Brown announced in 2009 that we had just 50 days to save the Earth. Then again, playing the long game can also catch up with you. In 2004, Observer readers were told Britain would have a ‘Siberian’ climate in 16 years’ time. We’re supposed to be in the midst of that now.

On the face of it, we should be grateful that these gloomsters make such oddly precise predictions. It’s like putting a sell-by date on their credibility. After all, when the soothsayer in question is proved wrong, they just shuffle off with their tail between their legs, never to be heard from again, right? In eight years’ time, when the planet hasn’t disappeared in a cloud of toxic gas, presumably Greta will throw up her arms and say: ‘Sorry guys. Looked like I was wrong about you ruining my childhood. I’m now going to become a flight attendant.’

But, weirdly, that never happens. No matter how often these ‘experts’ are shown to be no better at forecasting than Paul the Octopus — worse, actually — they just carry on as if nothing has happened. Take Paul Ehrlich, author of the 1968 bestseller The Population Bomb. ‘We must realise that unless we are extremely lucky, everybody will disappear in a cloud of blue steam in 20 years,’ he told the New York Times in 1969.