Climate scientists at the University of Rochester, the University of Alabama, and the University of Virginia report that observed patterns of temperature changes ("fingerprints") over the last thirty years are not in accord with what greenhouse models predict and can better be explained by natural factors, such as solar variability. Therefore, climate change is “unstoppable” and cannot be affected or modified by controlling the emission of greenhouse gases, such as CO2, as is proposed in current legislation. These results are in conflict with the conclusions of the United Nations Intergovernmental Panel on Climate Change (IPCC) and also with some recent research publications based on essentially the same data. However, they are supported by the results of the US-sponsored Climate Change Science Program (CCSP).

Lead author David Douglass said: “The observed pattern of warming, comparing surface and atmospheric temperature trends, does not show the characteristic fingerprint associated with greenhouse warming. The inescapable conclusion is that the human contribution is not significant and that observed increases in carbon dioxide and other greenhouse gases make only a negligible contribution to climate warming. Co-author John Christy said “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. We have good reason, therefore, to believe that current climate models greatly overestimate the effects of greenhouse gases. Satellite observations suggest that GH models ignore negative feedbacks, produced by clouds and by water vapor, that diminish the warming effects of carbon dioxide.” The report is published in the December 2007 issue of the International Journal of Climatology of the Royal Meteorological Society [DOI: 10.1002/joc.1651].