Sir David Attenborough is to present an "urgent" new documentary about climate change for BBC One.
The one-off film will focus on the potential threats to our planet and the possible solutions.
The broadcaster says "conditions have changed far faster" than he ever imagined when he first started talking about the environment 20 years ago.
The documentary will show footage showing the impact global warming has already had.
It will also feature interviews with climatologists and meteorologists to explore the science behind recent extreme weather conditions, including the California wildfires in November 2018.
Last December, Sir David called climate change "humanity's greatest threat in thousands of years" at the opening ceremony of the United Nations climate change conference.
He said it could lead to the collapse of civilisations and the extinction of "much of the natural world".
Earlier this year he spoke to Prince William at the World Economic Forum about how people must care, respect and revere the natural world.
Sir David, 92, said that when he started his career in the mid-1950s, he did not think there was anybody who thought "there was a danger that we might annihilate part of the natural world."
"It may sound frightening, but the scientific evidence is that if we have not taken dramatic action within the next decade, we could face irreversible damage to the natural world and the collapse of our societies," he says in the documentary.
The BBC said the film would "deliver an unflinching exploration of what dangerous levels of climate change could mean for human populations."
"There is a real hunger from audiences to find out more about climate change and understand the facts," said Charlotte Moore, the BBC's director of content.
"We have a trusted guide in Sir David Attenborough, who will be speaking to the challenging issues that it raises, and present an engaging and informative look at one of the biggest issues of our time."
Climate Change - The Facts will be broadcast this spring.