I just arrived in Paris for the global climate talks that start here today, and one of the first things I saw when I turned on my computer was the stream of photos coming from thousands of Global Climate March events across the globe.

What I saw was the beauty and power of a growing movement.

Melbourne hosted Australia's biggest climate action ever (60,000 people!), tens of thousands of Filipinos danced through Quezon City for climate justice, Egyptians ran and then marched through the streets of Cairo -- and so much more.

In total over 785,000 people marched this weekend, making it one of the biggest climate mobilizations ever in history.

There is obviously still a long fight ahead of us. But particularly after this weekend, it's becoming harder and harder to avoid the conclusion that we're close to something very big: a moment when the world can break free of fossil fuels, keep carbon in the ground, and build a just transition to 100% renewable energy for all.

I also want to mention the dedication of our team in Paris, who have worked through both heartbreak and a constantly shifting landscape about what activities the climate movement can take on there. Despite tight restrictions on activism placed by the French government, yesterday thousands of people formed a human chain stretching through the heart of the city to show their resolve to continue the fight for climate justice:

Then, this morning I helped hand millions of petitions calling for 100% clean energy for all to the President of the Marshall Islands, Christopher Loeak, who then carried them to heads of state as talks began.

Those messages are the beginning of an important two-week debate about the planet's future. There will be much to do afterwards, but what happens here in Paris is a crucial piece of the puzzle. If you want to stay up to date with breaking news from the talks, and weigh in on crucial issues as they develop, click here to be part of the Paris Rapid Response team.

You can also keep plugged in via’s TwitterFacebook Page, or our Live Blog from ParisWe’ll have some updates this week, but the biggest issues will be decided as the clock ticks down in week two.

Here's the line in Saturday's New York Times that sums up what's at stake: "If successful, the Paris meeting could spur a fundamental shift away from the use of oil, coal and gas to the use of renewable energy sources such as wind and solar power."

I'll be in the talks here for most of the next week. Everyone inside in Paris will be thinking of you outside, and the work you're doing to make that shift possible. If -- or when -- this transition happens, you will be a critical part of it.

With gratitude,