NCPA - National Center for Policy Analysis


January 14, 2008

Computer models that form the basis for future global warming predictions have projected significantly more warming in recent years than has actually occurred, according to the authors of a study published in the International Journal of Climatology.

According to the authors:

  • Model results and observed temperature trends are in disagreement in most of the tropical troposphere, being separated by more than twice the uncertainty of the model mean.
  • In layers near 5 kilometers, the modeled trend is 100 to 300 percent higher than observed, and, above 8 km, modeled and observed trends have opposite signs.


  • Satellite data and independent balloon data agree that atmospheric warming trends do not exceed those of the surface.
  • Greenhouse models, on the other hand, demand that atmospheric trend values be 2-3 times greater.
  • Satellite observations suggest that greenhouse models ignore negative feedbacks, produced by clouds and by water vapor, that diminish the warming effects of carbon dioxide.

"This new study adds another nail to the coffin of alarmist global warming theory," said Sterling Burnett, senior fellow at the National Center for Policy Analysis.

"Alarmist global warming theory is totally dependent on computer models predicting accelerating warming in the future," Burnett noted, "yet the models have predicted such warming in the past, and the predicted warming has failed to materialize.  This hardly seems a reliable indicator of future warming."

Source: Drew Thornley, "Computer Models Fail to Predict Climate," Heartland Institute, February 1, 2008.

For study abstract:


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