350 is the safe limit to avoid runaway climate change

350 ppm (parts per million) is the safe upper limit for the amount of carbon dioxide in the atmosphere that we need to achieve to prevent runaway climate change. The world’s leading climate scientist, James Hansen, says: “If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm.” Spread the number.