Scientific Consensus and the IPCC

The reports of the Intergovernmental Panel on Climate Change (IPCC) are based on scientific consensus. Scientists have been wrong before: the Earth was thought to be flat, bodily fluids were thought to be associated with personality types (the four humors) as was the shape of the skull (phrenology), and during the 1970's climate scientists thought the world might be cooling. At one time, all these ideas more or less commanded scientific consensus. Should we believe the IPCC scientific consensus today?

First, we no longer accept flat-earth theories or phrenology based on the accumulation of (negative) evidence over time. The initial global cooling pattern was based on satellite data that was not corrected for changes in satellite orbits (the red line in the graphic above shows the uncorrected data, the blue line shows the corrected data that now agrees with other measures of global temperature--presented today in the Global Warming Debate). Second, since it takes time for data to accumulate, be analyzed, reanalyzed, critiqued, and possibly refuted, we are asking a lot of the IPCC. They are making their assessments based on reading the current, peer-reviewed literature.

Some climate change critics have submitted their results to peer-reviewed journals but most simply present their conclusions based on cherry-picked data or pure opinion. Time will resolve these disagreements but many scientists are concerned that we don't have the luxury of time.