Amazingly, this one is from NASA, citing doubt in the climate models that have become the mainstay of the AGW issue. This is from a NASA publication.
Global records of surface temperature over the last 100 years show a rise in global temperatures (about 0.5° C overall), but the rise is marked by periods when the temperature has dropped as well. If the models cannot explain these marked variations from the trend, then we cannot be completely certain that we can believe in their predictions of changes to come.
The cover page of the PDF is below. Click to read it.
Here’s the most interesting part. It is from April 1998. What happened then to make NASA give up their caution in climate models?
MBH98, IPCC’s NGO fest?, Gore?
We don’t see such caution in publications today. Instead we see the word “robust” overused.
[ Added: This publication also states on p.3 that most of the 20th century warming occurred before 1940, but that was “revised” in the version 4 years later: http://hockeyschtick.blogspot.com/2010/04/nasas-changing-facts.html ]
Yet the dips of the 1940’s and the 1970’s still have not been explained by models. If there is a NASA publication that shows that they have such a model that explains the concern raised in 1998 that I’ve missed, readers feel free to point it out in comments.
Above: From Climate Skeptic.com we see one explanation,which looks much like what Girma Orssengo recently published on WUWT in