Everything you need to know about climate change in 5 minutes
Why’s everyone so down on carbon?
Carbon dioxide is one of a set of so-called greenhouse gases. They get this name because they let sunlight in, but won’t let heat back out into space, keeping the Earth warm, acting a bit like a greenhouse.
We want some of this effect. Without it, Earth would be a lot colder. The problem is that human activities — especially over the last few centuries — have increased greenhouse gas emissions to a point where it’s dangerous.