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Pachauri endorses 350ppm CO2 target

Rajendra Pachauri, chairman of the policy-neutral Intergovernmental Panel on Climate Change, has never been shy of speaking his mind on climate policy.

“I feel I have responsibility far beyond being a spokesman for the IPCC. If I feel there are certain actions that can help us meet this challenge, I feel I should articulate them,” he told Nature two years ago (Nature, 450, 1150-1155; 2007; subscription required).

He’s just articulated them again, calling for atmospheric carbon dioxide concentrations to be kept below 350 parts per million. (Current levels are around 387 ppm, and in its 2007 report, the IPCC took 450 ppm as a key target):

“As chairman of the Intergovernmental Panel on Climate Change, I cannot take a position because we do not make recommendations. But as a human being I am fully supportive of that goal. What is happening, and what is likely to happen, convinces me that the world must be really ambitious and very determined at moving toward a 350 target.” (AFP)

The statement was music to the ears of environmental writer Bill McKibben, the founder of, whose url explains its mission. In a Guardian blog, he called it “amazing news”.

Nature features editor Rich Monastersky wrote in an April 2009 article (Nature 458, 1091-1094; 2009, subscription required): “The difference between 350 and 450 is not just one of degree. It’s one of direction. A CO2 concentration of 450 p.p.m. awaits the world at some point in the future that might conceivably, though with difficulty, be averted. But 350 p.p.m. can be seen only in the rear-view mirror.”

Here’s McKibben making his point again on the Colbert Report a fortnight ago:

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  1. Report this comment

    Anthony T Simon III said:

    350 PPM is 9% of our current level of CO 2 of 3.8 PPK

    Or could it be that they meant 3,500 PPM? Or, could it be they (the So Called “Scientists”) are that STUPID when it comes to decimal points? Or could they be serious? Humans are “Allegedly” responsible for less than 20% ( as if it was possible to Quantify) of the Atmospheric CO 2, so if we WIPED OUT the ENTIRE Human Race we would still have another 60%> to go, and then who will be alive to do all that work saving the Planet? Why are we letting people that can’t do 4th Grade Math make policy for the whole WORLD, at Americas Expense?

    Ps as near as I can figure the only life that will left at 350 PPM will be Lichen, that should make Al Gore happy.

    Anthony T. Simon III

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