As the United Nations climate meetings heat up again this year, our fight for 350 is just getting started. Countries here in Bangkok are setting the negotiating agenda for the year and there are efforts to not just remove mention of 350 ppm from the text, but to seriously limit discussion of how to reach a global goal to save our planet.

Thankfully, a coalition of island nations and campaigns are fighting back. Negotiators from the most vulnerable countries, our strongest allies in this struggle, are working behind the scenes to make sure that 350 stays in the discussion. And in yesterday’s plenary discussion, Grenada spoke on behalf of the Association of Small Island States (AOSIS) about the need to meet the 350 goal.

Youth delegates from impacted countries demonstrate for 350 at last year's climate talks in Cancun.

But we’ve got a lot more work to do. All-eyes are now on Durban, South Africa, where this December, delegates from around the world will attempt to make substantial progress on the international climate treaty they failed to finish in Copenhagen. Such a treaty is an essential part of creating a global framework for addressing the climate crisis and needs to be fought for.

There is much fighting over the legal form the treaty will take, whether it will be a continuation of the Kyoto Protocol, a continuation of Kyoto with new elements, or a new treaty all together. These are important discussions. But just as essential is whether the treaty, no matter its form, actually deals with the climate crisis. This question will be up for debate in Durban, since one of the major goals of the meeting is discussing a long-term global target for reducing emissions.

This is what we’ve been waiting for: a chance to put 350 at the center of a new set of global commitments.

Why is 350 ppm so important? Here’s the simple reason: it’s about survival. Thanks to your hard work – over 10,000 demonstrations over the last two years — 350 has become a symbol of a safe-climate future and the changes we need to get there. In three simple digits, 3-5-0 gives us a way to measure who’s serious about protecting our future and who’s willing to let big polluters steal it from us.

Here’s the scientific reason: the latest science shows that any concentration of carbon dioxide in our atmosphere above 350 parts per million is not compatible with the planet on which “civilization developed and life on Earth is adapted.” Right now, we’re at almost 390 ppm and already seeing the devastating impacts of climate change, from fires in Russia to floods in Pakistan.

If the United Nations does not set a long-term goal of 350 ppm, it will not only be ignoring a scientific imperative, but will be leaving plenty of room for nations to cheat on their commitments. Whereas a concentration target, like 350, leaves little doubt of what needs to be done, temperature targets, like limiting global warming to 2 degrees C, are easy to manipulate: this is why the United States can tacitly recognize the 2 degrees goal, but offer such pathetic commitments. As founder Bill McKibben has said, "Pretending that the 350 limit doesn't exist won't actually fool physics.”

President Nasheed speaking in support for 350 at the UN Climate Talks in Copenhagen.

As we work towards the meetings in Africa, our allies here at the United Nations will be continuing to work on the inside of the process to keep 350 ppm on the agenda. But they need our support. Without a public outcry, the voices of the most powerful – the largest polluting countries – will be able to silence the voices of the most vulnerable. By organizing more of a grassroots movement across the planet, is at the forefront of this fight.

Your work of building local groups, pushing for practical and political action at the community level, and coming together with us to create national and global change, is absolutely essential. Now, more than ever.

In the words of President Nasheed of the Maldives, “I have three words to say to the doubters and deniers. Three words with which to win this battle. Just three words are all I need. You may already have heard them. Three – Five – Oh.”

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