In an interview with Agence France Presse, Rajendra Pachauri, the UN's top climate scientist and head of the Intergovernmental Panel on Climate Change, stated the following when asked if he supported calls to keep atmospheric carbon dioxide concentrations below 350 parts per million (ppm):
"As chairman of the Intergovernmental Panel on Climate Change (IPCC) 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."
The IPCC's last report, which came out in the winter of 2007, didn't actually set a target for CO2, but it was widely interpreted as backing a goal of 450 ppm, a number that many environmental groups and governments (including the Obama administration) have since embraced.
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