At 93, David Attenborough knows he doesn't have long left. But he's terrified for our planet.

David Attenborough knows the natural world, in all its capacity, more intimately than almost any other living person.

The broadcaster and environmentalist has become the familiar face (and voice) of the natural world.

Fifteen species, both living and extinct, have been named in his honour.

And he’s terrified about the future state of the environment.

Speaking to former UN climate chief Christiana Figueres on her podcast Outrage and Optimism, he shared that he doesn’t think about the future of the world too much, because it’s terrifying.

“I don’t spend time thinking about that because I can’t bear it. I’m just coming up to 93, and so I don’t have many more years around here. I find it difficult to think beyond that because the signs aren’t good,” he responded when asked what the world would look like for his great-grandchildren.

He continued to applaud the work of young people advocating for the environment.

“[Young people] understand the simple discoveries of science about our dependence upon the natural world,” he said. “My generation is no great example for understanding – we have done terrible things.”

He added that he has taken comfort in the worldwide protests by young people.

“That is the one big reason I have for feeling we are making progress. If we were not making progress with young people, we are done,” he said.

“They can see perhaps more clearly than the rest of us who have been around for some time… We older ones should take notice of what they say.”

In December last year, Attenborough urged world leaders, meeting in Poland, to agree on how to limit global warming and tackle “our greatest threat in thousands of years”.

“Leaders of the world, you must lead,” said the naturalist, who was given a “People’s seat” at the two-week UN climate conference alongside two dozen heads of state and government.

He explained that the state of the environment lies in the hands of man.

“The continuation of our civilisations and the natural world upon which we depend, is in your hands,” he said.

“Climate change is running faster than we are and we must catch up sooner rather than later before it is too late.”

Attenborough’s series Our Planet further illuminates the danger our environment is in.

Throughout the eight-part series, he explores the impacts of industrialisation and climate change on our earth.

The destruction of natural environments and animal habitats, over-fishing, melting ice and rising sea levels, are all areas of high risk.

“What we do in the next 20 years will determine the future for all life on earth”, he warns.

It’s time to listen.

For more information on how to save our planet, visit ourplanet.com. Our Planet is now streaming on Netflix.