Climate Change 9: How Useful (or Accurate) is a Forecast 75 Years Out That Won’t Be Noticeable for 300 Years?

Climate scientists Patrick Michaels and Paul Knappenberger’s terrific new book exposes the “pseudoscience” that the “the debate is over” crowd relies on for their alarmist dictates.  That crowd is big and powerful, but nowhere near 97% of climate scientists (or anybody else) endorse the impoverishing policies that will change our climate in ways that won’t even be measurable 75 years from now.

The book, Lukewarming: The New Climate Science that Changes Everything, acknowledges that climate change is real and partially man-made, but shows that the mild, gradual warming we are experiencing doesn’t come close to the catastrophic levels predicted by the model estimates used by the UN’s Intergovernmental Panel on Climate Change (IPCC).

Figures in the third National Climate Assessment indicate that declining winter precipitation in Texas will be statistically detectable (meaning that it will average one standard deviation below the current average) over 1,200 years from now. The average time for any change to be detectable is around 300 years, thanks to the great natural year-to-year variability in precipitation data. Data from the National Centers for Environmental Information, National Oceanic and Atmospheric Administration (

The authors of the Third National Climate Assessment would have done well to spend a little time discussing the utility or usefulness of their forecasts.  After all, how useful or significant is a prediction that won’t be noticed for hundreds of years?

Michaels and Knappenberger examined the regions where “high-confidence” precipitation predictions were made and found that “averaged across all seasons, it will take approximately 297 years before a state’s seasonal-projected precipitation change emerges from background variability.”

The fact that it generally takes so long to observe any change in forecast precipitation means the forecasts have very little utility.  Ask yourself how much you would be willing to risk on a questionable forecast of a change in rainfall that can’t be detected for another 300 years.  …

Lukewarmers are concerned when governments issue climate change forecasts call “clear patterns of precipitation change” without discussing their utility.

Peter Zeller is Director of Operations at Center of the American Experiment.