The Empire-State-Sized Alarm Bell In Sir David Attenborough's New Documentary

Sir David Attenborough is back with a new documentary called 'Our Planet', and he sat down with Rove McManus to tell The Project all about it.

The new documentary took more than four years to film and sees Attenborough travel to 50 countries across all seven continents.

At the age of 92, Attenborough is still as passionate as ever about the planet and the dangers it faces.

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While filming 'Our Planet', there was one moment Attenborough recalls that "astonished" him when he saw the footage.

"A slab of ice, the size of the Empire State Building, coming off the end of a glacier and then slowly falling into the water," Attenborough told The Project.

But Attenborough won't remember the moment for good reasons, but rather as a "powerful" reminder of the effect humans are having on the planet.

"As a symbol of what we are doing to the planet in terms of rising temperatures, you couldn't have anything more powerful'," he said.

And despite having spent decades witnessing the most magical of moments in the wilderness, Attenborough is still amazed at the the things he sees while making his documentaries.

"There are such wonderful things that really make your pulse throb," Attenborough said.

He said he was drawn to making 'Our Planet' because of the "unpredictability" nature of making it.

"When you start on these things you never know how they are going to end up," Attenborough said.

"You don't know what triumphs you're going to see."

'Our Planet' begins streaming on Netflix on April 5.

Watch Part 1 of Rove's interview with Sir David Attenborough on The Project at 6.30pm Monday on Channel 10, and catch Part 2 on Tuesday.