According to the federal agency, it measured and compiled data from about 40 sites around the globe.
In a statement in March, Pieter Tans, lead scientist of NOAA's Global Greenhouse Gas Reference Network, said that the agency first reported 400 part per million when all of Arctic locations reached that figure in the spring of 2012. According to Tans, reaching the level of 400 parts per million as a worldwide average is a significant milestone.
Tans said, "This marks the fact that humans burning fossil fuels have caused global carbon dioxide concentrations to rise more than 120 parts per million since pre-industrial times. Half of that rise has occurred since 1980".
As per the reports, the implications of these facts are sobering. Even if world succeeds in stabilizing the rate of carbon emissions, it will not help in preventing climate change. According to the NOAA, by summers of 2040, the Arctic will be ice-free-a fact.
Dr. Ed Hawkins, climate scientist from the University of Reading, said that new figures on the concentrations of the carbon dioxide are surprising. The last time the planet had that much carbon dioxide gas in the atmosphere was over a million years ago. That time, modern humans had not even evolved yet, Hawkins added.
The federal agency and some of its partner agencies consider the new measurements to help policymakers and the scientific community. The 40 global sites that were selected by the agency for sampling are in remote areas.
