Why it's worse than they thought-

This is important, so I'm going to repeat it; good story today from the BBC; Arctic Melting Faster Than Predicted. "This is the third time in the last few months that studies have suggested the IPCC's latest major global climate analysis, the Fourth Assessment Report, is too conservative."

You'll hear that refrain frequently now. The crux of this particular story is the heavyweight climate modelers are saying they're puzzled about why their intensely careful models are always UNDER estimating the problems.

Here; at least in part, is WHY; and this is NOT a factor they recognize, or are dealing with. And it's quite serious.
Not Refrigerators

The relevant bit starts about in the middle of the post.

For all the training our PhD's go through (and I've been through) - there are very few who are trained in genuine "oversight" of other researchers' thought processes. Very few indeed.