The study's author told Fox News that on average, the predictions forecasted two times more global warming than actually occurred.
Climate scientist John Christy, a professor at the University of Alabama in Huntsville, said that it shows that there really is something that needs to be fixed in the climate models.
Christy said that he looked at 73 climate models going back to 1979 and every single one predicted more warming than happened in the real world.
Meanwhile, Melanie Fitzpatrick, a climate scientist with the Union of Concerned Scientists, told the publication that the climate models will likely be correct over long periods of time, but there are too many variations in climate to expect models to be accurate over two decades.
Christy said he believes the models overestimate warming because of the way they handle clouds.
Answering to why the models over-predict, the study revealed that an overestimate of the power of CO2 as a greenhouse gas could be one of the reasons.
The study is published in the journal Nature Climate Change.
--ANI (Posted on 14-09-2013)