NASA doubts climate model certainty

WATTS UP WITH THAT, 4/27/2010 by Anthony Watts - 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.