Earth's CO2 levels just crossed a really scary threshold - and it's permanent

According to the latest figures, levels of atmospheric carbon have officially surpassed 400 parts per million (ppm), and there’s little hope of returning them to safe levels - the situation is now permanent.
Read more: http://www.sciencealert.com/earth-s-co2-levels-just-permanently-crossed-a-really-scary-threshold?source=Snapzu