Tongass National Forest
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Human blame 'rock solid' on climate change

A landmark report by United Nations scientists is expected to say they are more convinced than ever that global warming is man-made.

The assessment by the Intergovernmental Panel on Climate Change IPPC will be published later.

Sir Mark Walport, the government's chief scientific adviser on climate, told the Today programme's James Naughtie that this was "an extremely important moment because the IPPC report [shows]... that humans are altering the climate and the evidence is absolutely rock solid."

First broadcast on BBC Radio 4's Today programme on Friday 27 September 2013.

  • 27 Sep 2013