Climate Collision Course: CO2 Levels About to Hit 400 PPM | Common Dreams
"The world is likely days away from a "sobering milestone" in our planetary history.
Concentrations of the greenhouse gas carbon dioxide will likely reach 400 parts per million (ppm) for first time in human history, say scientists at the Scripps Institution of Oceanography, and unless drastic action is taken, we're on track to hit 450 ppm in the near future."