350 PPM CO2: Earth’s Tipping Point?
Bill McKibben is an American environmentalist and author who frequently writes about global warming and alternative energy and advocates for more localized economies. He is the founder of 350.org, an international climate campaign.
According to McKibben, 350 is the most important number in the world–it’s what scientists say is the safe upper limit for carbon dioxide in the atmosphere.
Two years ago, after leading climatologists observed rapid ice melt in the Arctic and other frightening signs of climate change, they issued a series of studies showing that the planet faced both human and natural disaster if atmospheric concentrations of CO2 remained above 350 parts per million.
In this excerpt of a Sydney lecture, McKibben talks about how climate science and climate politics are quickly evolving and how we now have a much more specific idea both of the peril we face and the steps (large and difficult) necessary to solve it.
On October 24, the International Day of Climate Action will cover almost every country on earth, the most widespread day of environmental action in the planet’s history.
There will be big rallies in big cities, and incredible creative actions across the globe: mountain climbers on our highest peaks with banners, underwater demonstrations in island nations threatened by sea level rise, churches and mosques and synagogues and ashrams engaged in symbolic action, star athletes organizing mass bike rides–and hundreds upon hundreds of community events to raise awareness of the need for urgent action.
Every event will highlight the number 350–and people will gather at some point for a big group photo depicting that all important message. At 350.org, we’ll assemble all the photos for a gigantic, global, visual petition.
