The most recent science tells us that unless we can reduce the amount of carbon dioxide in the atmosphere to 350 parts per million, we will cause huge and irreversible damage to the earth. Since the pre-Industrial Revolution and for the entire evolution of the human species, concentration of carbon in the atmosphere remained roughly 275 parts per million. Until recently, scientists and policymakers have focused on what would happen if that number doubled to 550 and whether or not we could curtail human production of carbon enough to stop short of that point. Yes we could, but with immense difficulty. In the past five years, scientists grew concerned that the planet was reacting more quickly than expected to the approximately one degree fahrenheit increase in global temperature recorded over the past century. The rapid melt of most glacial systems, for instance, convinced many that 450 parts per million was a more prudent target. The news this fall that Arctic sea ice was melting at an off-the-charts pace and data from Greenland suggesting that its giant ice sheet was starting to slide into the ocean make even 450 look too high. Now, according to NASA scientist, James Hansen, the bottom line for the planet is 350 parts per million carbon dioxide in the atmosphere. We are currently at 383 parts per million.
Does that mean we're doomed? Not quite. Not any more than your doctor telling you that your cholesterol is way too high means the game is over. Much like the way your body will thin its blood if you give up cheese fries, so the Earth naturally gets rid of some of its CO2each year. We just need to stop putting more in and, over time, the number will fall, perhaps fast enough to avert the worst damage.
McKibben and many colleagues who started last year's Step It Up initiative are
planning an international campaign to unite the world around the number 350. The goal is to ensure that the solutions the world proposes to climate change are to scale with the level of crisis that this number represents.
McKibben from the 350.org site:
Everyone on earth, from the smallest village to the cushiest corner office, needs to know what 350 means. The movement to spread that number needs to be beautiful, creative, and unstoppable. What we need most right now are your ideas for how to take the number 350 and drive it home: in art, in music, in political demonstrations, in any other way you can imagine. We will connect actions all around the world and make them add up to more than the sum of their parts–but we don’t have all the ideas and all the inspiration. We need yours.
We're looking forward to celebrating along with all of you when we get to...