CO2 levels reach record high

Atmospheric CO2 concentrations reached record levels last year according to the UN World Meteorological Organisation.

The annual report show 2012 CO2 levels reached 393.1 parts per million (ppm); an increase in 2.2 ppm from 2011 and exceeding 350 ppm - believed by some to be the maximum safety limit.

While global CO2 concentrations tipped over 400 ppm earlier this year, the UN weather agency predicts average concentrations will reach 400ppm in 2016.

Read more at World Metereological Organisation