Detailed text transcripts for TV channel - MSNBC - 20130929:16:56:00
Since 2007. it's based on research by hundreds of the world's top climate scientists. they say it's irrefutable that humans are to blame. robin, with a welcome, can you talk about the differences between this report and the last one published back in '07? >> absolutely, alex. what's changed is not so much the data itself, besides some small fluctuations. it's largely what climate scientists have been saying for years. what has changed is the level of certainty. in the report they've said that since the 1950s, the earth has been warming and that's undebatable. but back in 2007, there was only a...