Substitute dairy with plant-based alternatives

target for each (for example, only reducing food waste by a quarter instead of a half, or overeating by only half as much as we do today) we could cut emissions by two-thirds. This would free up lots of space in our carbon budget and buy us some time to get our emissions from energy and other sectors to zero.

Genetic breeding gets a bad reputation in environmental circles, but it has been absolutely crucial to increasing crop yields across the world, and could play a much bigger role if we’re to develop agriculture that works well in a changing climate. Not only would it allow farmers to achieve good, stable yields, it could even mean we’d need to use

The amount of oxygen the Amazon consumes is almost exactly the same as the amount it produces. These cancel each other out, so it provides almost none of the oxygen in the atmosphere. It’s not just the Amazon. None of the world’s forests or vegetation give much to our oxygen supply. As the geologist Shanan Peters calculated: ‘if every living thing

But communities that achieved environmental sustainability were always small, and that’s because rates of child mortality were high: losing children stopped the population from growing. A world in which half of all children die is not meeting ‘the needs of the present generations’ and is therefore not a sustainable one.

Sustainability is humanity’s North Star. Make sure current generations have opportunities for a good life, shrink our environmental impact so that future generations have the same (or better) opportunities, and let wildlife flourish alongside us. That’s the dream. And I hope I’ve shown over the course of the book why it’s one I believe we can

Crops that need fewer chemical inputs, are more resistant to drought, and get higher yields – what’s not to like? It sounds like a win-win for people and planet. Strangely, many environmentalists are strongly opposed to cross-breeding and genetic modification of crops even though they have been incredibly important for protecting ecosystems and

But my perspective on 2°C has changed. I’m now cautiously optimistic that we can get close to it. It’s more likely than not that we will pass 2°C, but perhaps not by much. And there is still a reasonable chance – if we really step up to the challenge – that we can stay below it.

Scientists can calculate this magical ‘sweet spot’: the exact point where we can catch as much fish as possible without depleting their populations below their most productive levels. It’s called the ‘maximum sustainable yield’.