29/09/2015 06:47 BST | Updated 29/09/2016 06:12 BST

Shell Quitting the Arctic Is a Monumental Victory - Let's Keep Campaigning for a Greener Future

Yesterday Shell announced it was quitting its Arctic drilling programme. Let me just repeat that in case you, like me, couldn't quite fathom this wonderful piece of news: Shell is quitting its hunt for dirty oil in the Arctic.

The thing is about these oil companies is they try and make us believe they rule the world, that their tomorrow is the only tomorrow. But today shows that the future can be rewritten. Once Shell called us emotional dreamers. But look who's laughing now.

I first went to the Arctic two years ago. I've seen the beauty of that place - and I've seen the ice melting. Drilling for oil here would always have been disastrous - both for the fragile ecosystem at risk of an oil spill, as much as for the unburnable carbon Shell wanted to dredge up from leagues beneath the sea. I've felt to the core of my being how precious this place is and how incredibly important it is that we protect it.

Going there with my daughter was both wonderful - and scary. It's her lifetime that's at stake. This moment of getting Shell out will be looked back on by her generation as a turning point - for the climate and for the planet.

We wouldn't be standing here today celebrating this victory if it wasn't for the millions of people who have come together to stop Shell and other oil companies like them. In my wildest dreams I wouldn't have thought that when the ice breaker turned round to Portland that we were two months from victory.

Shell execs might not publicly admit that our movement stopped them - but reading between the lines we can all see public outrage on Arctic drilling was a huge concern for them. The whole fossil fuel industry is facing an existential crisis: attempting to present itself as responsible guardians of the future at the same time as pilfering the planet and risking the future of life on earth. This backdown is the company falling flat on its face.

This morning I felt like I woke up to a whole new world of possibilities. We didn't know when this win would come - we knew we'd stick it out, but we didn't know when we'd reach this horizon. And now we have. This is a monumental victory. Let's keep at it and create an Arctic Sanctuary once and for all, and put ourselves on a path towards a safe climate.

Aurora the beautiful polar bear will set off from Shell's London HQ to the climate talks in Paris today. And she'll confront Shell there too - because we know it's trying to water down climate policy behind the scenes.