Prediction is hard, especially about the future, said Neils Bohr. So why not try to predict the past? A study in the Royal Metereological Society journal did just that, focusing on the best available evidence of the past 25 years. Measuring instruments have improved immensely in accuracy and coverage in recent decades, using satellites, weather balloons and surface sensors.

"The usual discussion is whether the climate model forecasts of Earth's climate 100 years or so into the future are realistic," said the lead author, Dr. David H. Douglass from the University of Rochester. "Here we have something more fundamental: Can the models accurately explain the climate from the recent past?  It seems that the answer is no."

"The 22 climate models used in this study are the same models used by the UN Intergovernmental Panel of Climate Change (IPCC), which recently shared a Nobel Peace Prize with former Vice President Al Gore."

"We suggest ...  that projections of future climate based on these models should be viewed with much caution,"  said Dr. Fred Singer from the University of Virginia.