The actor and climate change activist told ITV News she has hope in the younger generation who are “willing to put themselves in danger” to bring the climate crisis to the fore.
Asked if she believes we are reaching the point of no return, she argued much of the planet has long-since passed that stage.
“I think for many species and many parts of our planet we reached that a long time ago, it’s not helpful to think that point of no return is coming towards us,” she said.
“It’s better to face the facts that this is it, we’re in it, and everything depends on what we do now.”
She said the group is “incredibly effective” at putting climate change on the agenda.
“They [Extinction Rebellion members] are willing to put themselves in danger, to get a criminal record, to upset their parents at a time when they should be enjoying their time at school or uni,” she told ITV News.
“To meet them, they made me feel so ashamed that we have let them down to such a degree that they were willing to turn their back on their own futures, everything we have been taught, jobs, families... they can't think like that.
“[The] government isn’t doing it and the only option is to protest.”
Dame Emma’s decision provoked criticism after she flew back to London in the days before the protests, which she told ITV News she expected.
Unmoved by the critics, she said it doesn’t matter if she gets “pilloried” and said she flies “much less” than she used to.
“The message from Extinction Rebellion wasn’t that no one can fly it was that for decades now we have been asking for clean energy and this has been ignored,” she said.
“I may well be hypocritical by flying but I’m conscious of flying so I fly much less, but sometimes I have to when I’m working. But I’ll continue to find ways to get to places without flying.”
She admitted her frustration with the world’s failure to act on climate change and banged her head on the table when asked about the Paris Accord, which she described as a “desperate but very good act” before pointing out most countries are still way off their targets.
But she finds hope in the youth.
She said: “If ever I do feel depressed, I plug into the young who are so hopeful.
“They are full of energy and hope as they are turning around and saying to us that we have to act now, I think that is fantastic.
"I think this generation is remarkable”
Despite her passion on the issue, she dismissed the idea of going into politics herself and insisted she can better serve as an activist and supporter.