An excellent article that really pins down the uncertainty around the data being used to try and shift public policy in a rather large way, which most sensible people realize will seriously disrupt the economies of most modern societies.
September 20, 2007
One More Reason to Distrust Global Warming Predictions
By Jerome J. Schmitt
"Garbage in, garbage out" has become a cautionary maxim of the computer age, reminding us that bad data corrupts computer software and many other artifacts of modern technology. What then are we to make of global warming scientists who present us with temperature charts purporting to display changes in the global mean temparture for the last century-plus. Who was measuring global mean temperatures in the 1880s?
Political observers are familiar with "margin of error" in opinion polls. Polls seek to measure the political prospects of candidates competing for elected office. The "true value" of the candidate's political viability is established when the votes are counted.
Similarly, the mathematics of physical measurements require knowledge of potential sources of errors in measurements to place bounds on the likely true value. Estimated errors are expressed as "error bars" in plots of empirical data. The true value could be any value within the margin of the error.
With this background, I was astonished to see the assurance with which climatologists writing about global warming report Global Mean Temperature over Land & Ocean as far back as 1880 -- as shown in the US Government's "official" NOAA Chart reproduced below.
It is noteworthy that most reproductions of this chart in the popular press omit the error bars. Who could possibly have been measuring Global Mean Temperature (GMT) so accurately (±0.14°C) in 1880? For context, remember that in the 1880s, Mr. Stanley was searching for Dr. Livingston, who was totally lost while exploring Africa for the source of the Nile. Put another way, as seen from the error bars, why has science's ability to measure global mean temperature increased in accuracy only by a factor of two (±0.07°C) in the last 125 years?
