Atmospheric carbon dioxide reaches all-time high

The amount of carbon dioxide in the Earth's atmosphere is set to reach a record high - for our lifetime - over the next week or so. Currently the level of carbon dioxide in the atmosphere is being measured at 399.72 parts per million (ppm) and will soon reach 400ppm. This is big news in the fight against climate change.

This high level of CO2 has not happened - it is speculated - since the Pliocene epoch. This phase in the Earth's history happened between 3.2 million and 5 million years ago, when the climate of the planet was much higher than the climate today.

The Earth Systems Research laboratory Hawaii - run by the US government - did not expect the readings to reach the 2013 peak of 400ppm until mid-May. The laboratory has been recording weekly averages of 398.5ppm, with the highest daily average being taken on 25 April at 399.72ppm. Readings above 400ppm have been recorded in the high Arctic six times in April.

Ralph Keeling, a geologist with the Scripps Institution of Oceanography operating in the Hawaiian observatory, said: "I wish it weren't true but it looks like the world is going to blow through the 400ppm level without losing a beat. At this pace we'll hit 450ppm within a few decades." He added that "The increase in the global burning of fossil fuels is the primary cause of the increase."

The Mauna Loa station has been monitoring the levels of CO2 in the Earth's atmosphere for over 50 years and is considered the ultimate authority. The station is located at 3,400m, far away from sources of major pollution in the Pacific Ocean. It is estimated that CO2 emissions rose from 280ppm at the beginning of the industrial revolution to 316ppm when the Moa Loa observatory started measuring atmospheric CO2 in 1958. The increase in the use of fossil fuels for energy production around the world is attributed as the main reason for the steep increase in the CO2 levels.

Tim Lueker, oceanographer and carbon cycle researcher with Scripps CO2 Group, said: "The 400ppm threshold is a sobering milestone, and should serve as a wake up call for all of us to support clean energy technology and reduce emissions of greenhouse gases, before it's too late for our children and grandchildren."