It is hard not to feel anxious about climate change. After all, the world is already experiencing the effects of global warming - and scientists tell us much worse could still be on its way.
For some, tackling climate change feels like a lost cause: a job so big and complex, that it is doomed for failure - the demise of the human species is inevitable. This is wrong. But even though this view is predicated on falsehoods and distortions, it appears to be spreading online - and a lot of young people are getting sucked in. Why is "doomism" going viral? And who are the activists and campaigners standing up to it?
Presenter: Marco Silva
(Illustration: Hands holding electronic devices showing melting planets. Credit: Sandra Rodríguez Chillida/BBC News)