Sunday , October 22 2017
Home / Robert Murphy: Free Advice / Is Jerry Taylor Doing What I Think He’s Doing?

Is Jerry Taylor Doing What I Think He’s Doing?

Summary:
In researching another point, I came across an interesting argument from a 2015 blog post by Niskanen Center’s Jerry Taylor. (It summarized his contribution in a debate on carbon taxes.) It seems that JT is making a pretty bad inference from a chart, but since I’m not predisposed to agree with him, I’m seeking feedback from you folks. Here’s Taylor: We also hear quite a bit from the Right about how the computer models have wildly over-predicted warming and thus should not be informing our policy going forward. Again, courtesy of Berkeley Earth, let’s see how the computer models used in the fourth IPCC report (released in 2007) perform when run against Berkeley Earth’s historical temperature record. The multi-colored lines represent runs from the climate models featured in the fourth IPCC report. The heavy black line represents the Berkeley Earth land temperature record. The heavy red line represents the average of the various model runs. It would appear that the climate models used by the IPCC are now pretty good at replicating temperatures and are not, on balance, running hot. So my question: If the models were published in 2007, I’m assuming that means they were calibrated up to 2007 (or very recent) observations, right? If so, then the goodness of fit before 2007 isn’t really relevant. What matters is how the models performed out of sample, i.e.

Topics:
Robert Murphy considers the following as important:

This could be interesting, too:

Robert Murphy writes Neeley vs. Murphy on Carbon Tax

Robert Murphy writes Amplifying Oren Cass on a Carbon Tax, Part 2

The_Real_Fly writes Reminder: Experts Have Been Warning Us About Global Warming Since the 1930s

Robert Murphy writes More on Flood Statistics

In researching another point, I came across an interesting argument from a 2015 blog post by Niskanen Center’s Jerry Taylor. (It summarized his contribution in a debate on carbon taxes.) It seems that JT is making a pretty bad inference from a chart, but since I’m not predisposed to agree with him, I’m seeking feedback from you folks.

Here’s Taylor:

We also hear quite a bit from the Right about how the computer models have wildly over-predicted warming and thus should not be informing our policy going forward. Again, courtesy of Berkeley Earth, let’s see how the computer models used in the fourth IPCC report (released in 2007) perform when run against Berkeley Earth’s historical temperature record.

Is Jerry Taylor Doing What I Think He’s Doing?

The multi-colored lines represent runs from the climate models featured in the fourth IPCC report. The heavy black line represents the Berkeley Earth land temperature record. The heavy red line represents the average of the various model runs. It would appear that the climate models used by the IPCC are now pretty good at replicating temperatures and are not, on balance, running hot.

So my question: If the models were published in 2007, I’m assuming that means they were calibrated up to 2007 (or very recent) observations, right? If so, then the goodness of fit before 2007 isn’t really relevant. What matters is how the models performed out of sample, i.e. from 2007 forward.

And as Taylor’s own chart shows, the models predicted much more warming after 2007, than actually occurred.

So doesn’t this chart prove the exact opposite of JT’s point?

Robert Murphy
Robert Patrick Murphy (born 23 May 1976) is an American economist, consultant and author. He is an economist with the Institute for Energy Research (IER) specializing in climate change and a research fellow with the Independent Institute, He was a senior fellow in business and economic studies at the Pacific Research Institute, and he is an associated scholar at the Ludwig von Mises Institute. In addition to economic subjects, Murphy writes about, and has presented an online video class in, anarcho-capitalism on the Mises Institute website. Murphy also has written in support of Intelligent Design theory and expressed skepticism of biological evolution.

Leave a Reply

Your email address will not be published. Required fields are marked *