350.org is turning the page on the fossil fuel industry and building a clean, just future by connecting powerful grassroots climate movements around the world.
What's in a name? Ours, 350, is a number. And a very important one. It is a reference to 350 parts per million (ppm) – the concentration of carbon dioxide (CO2) in the atmosphere considered the safe limit to avoid the worst impacts of climate change. We are currently at 425.40 ppm.