There was all kinds of news about CO2 level reaching 400 ppm.
Energy Collective-by -May 11, 2013Climate Change and CO2 400 ppm ... on 400ppm, which is to say, an amount of CO2 in the atmosphere that's 400 parts per million, by volume.
Out of all the hype, National Geographic and The Economist tell the story behind the 50+ years of measurement started by Charles David Keeling.
Here is the National Geographic post.
Climate Milestone: Earth’s CO2 Level Passes 400 ppm
Greenhouse gas highest since the Pliocene, when sea levels were higher and the Earth was warmer.
Photograph by Jonathan Kingston, National Geographic
Published May 9, 2013
An instrument near the summit of Mauna Loa in Hawaii has recorded a long-awaited climate milestone: the amount of carbon dioxide in the atmosphere there has exceeded 400 parts per million (ppm) for the first time in 55 years of measurement—and probably more than 3 million years of Earth history.
And here is The Economist post.
Four hundred parts per million
The only good news about the Earth’s record greenhouse-gas levels is that they have been well measured
May 11th 2013 |From the print edition
The Economist honors the effort by Dave.
Scientists involved in other measurements of the Earth, and those who pay for their work, need to build on his legacy. So does anyone taking a position on global-warming, where numbers as clear as Keeling’s are a rarity. Measurements of the temperature of the ocean depths and the acidity of its surface waters, of the volume of the planet’s forests and the mass of its ice sheets (see article), need to be made not just for the few years of a specific research project. Their ceaseless continuance needs to be built into the planet’s infrastructure. A world in which governments claim to be committed to spending trillions of dollars to change the shape of the Keeling curve decades hence, but do not find the funds to produce consistent records of the change going on today, is one that still has lessons to learn from the patient chemist.
And National Geographyic as well.
When the elder Keeling started at Mauna Loa, the CO2 level was at 315 ppm. When he died in June 2005, it was at 382. Why did he keep at it for 47 years, fighting off periodic efforts to cut his funding? His father, he once wrote, had passed onto him a "faith that the world could be made better by devotion to just causes." Now his son and the NOAA team have taken over a measurement that captures, more than any other single number, the extent to which we are changing the world—for better or worse.