All coverage
There is more CO2 in the atmosphere today than any point since the evolution of humans
By James Griffiths
'We Don't Know a Planet Like This': CO2 Levels Hit 415 PPM for First Time in 3 Million+ Years
By Jon Queally
415.26 parts per million: CO2 levels hit historic high
By Patrick Galey
Climate change: CO2 levels hit 415 parts per million in human first
By Doyle Rice & Ryan W. Miller