By Bill McKibben, Cross-Posted from Planet Green

For the last 20 years or so, there’s been a reasonable excuse for not building a movement big and tough enough to tackle climate change: It had no chance. Washington was filled with such obstructionists that everybody knew meaningful change on a scale large enough to dent the carbon concentration in the atmosphere was pretty much doomed.

Well, we screwed up that excuse last November. With the advent of the Obama administration , there was suddenly at least the possibility of real change. It’s populated by people who believe in science, who think about the future instead of obsessing over the past, and who even believe in working with other countries.

But it would be utterly foolish to imagine they can do what they need to do by themselves.

For one thing, the scale of change required is so massive it must frighten even Barack. Look, in the last couple of years the science has been unremittingly dark. We now know that global warming is not a future problem—that it’s crashing over our heads right now. We know that from the evidence around us: the melting Arctic ice, the rapidly dying forests of the north, the spike in methane releases from beneath the tundra. And we know it from our best scientists: James Hansen and his team at NASA have said, unequivocally, that any concentration of carbon in the atmosphere greater than 350 parts per million is not compatible with the planet “on which civilization developed and to which life is adapted.” That’s Not Good News, since the current level is 387 parts per million and rising. That’s Not Good News because it means that we need to move very, very fast—Hansen’s data indicates that if the planet hasn’t stopped burning coal by 2030, we’ll overwhelm the planet’s systems and never get back where we need to go.

So we have a target—350 parts per million—and we have a political process, not only in this country, but internationally. It will culminate in December in Copenhagen, when the world’s leaders get together to sign a new treaty. At the moment it looks weak and tepid, but if we build a movement we can change that. We can scare some leaders, and we can open some political space for those, like Obama, who really want to do something.

But we can’t do it without you. On October 24, we’re organizing demonstrations and rallies and events in every corner of the planet to spread that 350 number—to set the bar for those Copenhagen talks Copenhagen Climate Congress to Synthesize New Science on Climate…. There will be climbers high in the Himalayas, and scuba divers on the Great Barrier Reef, and even a rally on Easter Island. But we need thousands more, including one in your community. It doesn’t need to be huge, but it does need to be clever. Check out the ideas people are hatching at, and by October turn yourself into an honest-to-God organizer. Because we’re not going to solve this one light bulb at a time, but we just might if we can build one light-filled, light-hearted, lightning-fast movement.

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