Uh-oh.
Carbon dioxide hits 400 ppm for the first time in human history
Carbon dioxide levels throughout the northern hemisphere hit 400 parts per million (ppm) for the first time in human history in April – the ominous threshold has been reached, and it continues to go up. Time is running out I’m sad that I was right when I wrote: The Inevitable 2014 Headline: ‘Global CO2 Level Reaches 400 PPM For First Time
