What is 350?

350 parts per million is what many scientists, climate experts, and national governments are now saying is the safe upper limit for CO2 in our atmosphere.  350 is a way to talk about global warming and climate change, and a simple, globally-understandable way to talk about where we need to be.  350 becomes even more important once you realize that we’re past it — current levels are at 392 and rising.

350 GraphAccelerating arctic warming and other early climate impacts have led scientists to conclude that we are already above the safe zone at our current 392ppm, and that unless we are able to rapidly return to below 350 ppm this century, we risk reaching tipping points and irreversible impacts such as the melting of the Greenland ice sheet and major methane releases from increased permafrost melt.

350 is the number that leading scientists say is the safe upper limit for carbon dioxide—measured in “Parts Per Million” in our atmosphere. 350 PPM—it’s the number humanity needs to get back to as soon as possible to avoid runaway climate change.

Want to learn more?  Check out 350 Science at 350.org.