There is an old joke about a driver stopping to ask a villager for directions. "Well", says the villager, "if that's where you're going, I wouldn't start from here". That describes our current status for saving the planet. Ideally, we would not start from here: ice sheets doomed, climate damage under way and barely any plausible path to achieving global net zero emissions by 2050.

But finally there is some good news. After decades in which we have essentially been driving a gas-guzzler around in circles, the next stretch of our journey to net zero looks more straightforward. We are entering a hopeful new era for climate action. People and green alternatives are readier, policymakers are moving from stick to carrot and good ideas will spread fast.