McKitrick at it again

I don't think I need to add much to Deep Climate's dissection of McKitrick's claims that one of his papers has been unfairly rejected, so I'll just make three quick points. McKitrick claims:

There was some excitement when a blogger found a minor error in our computer code (we had released the code at the time of publication), but we sent a correction to the journal right away and showed that the results hardly changed.

The "minor" error was confusing degrees with radians. As I wrote at the time:

correcting the error halves the size of the economic signal in the warming trend, reducing it from 0.16 (out of 0.27) to 0.09. McKitrick's correction states:

Outside the dry/cold regions the measured temperature change is significantly (previous: primarily ) influenced by economic and social variables.

That's quite a difference, so how can he say that their conclusions were not affected? Well, all the conclusion says is that there were socioeconomic effects, without mentioning their size. The size of the effects, which change substantially, are only mentioned in the body.

Secondly, Gavin Schmidt has conclusively demonstrated that McKitrick's correlations of temperature trends with economic indices are spurious, by showing that you get similarly "significant" correlations with trends from climate models which are independent by construction of such indices.

Thirdly, McKitrick has known about the problems with his theory for about ten years now. See Robert Grumbine's comments on the first (unpublished) version of McKitrick's theory:

He was fooling around with correlating per capita income with the observed temperature changes. He concluded that the warming was a figment of climatologists imaginations, as there was a correlation between money and warming. 'Obviously' this had to be due to wealth creating the warming in the dataset, rather than any climate change---his conclusion.

Along the way he:

1) selected a subset of temperature records
1a) without using a random method
1b) without paying attention to spatial distribution
1c) without ensuring that the records were far enough apart to be independant---ok, I shouldn't say 'he' did it, because he didn't. He blindly took a selection that his student made and which was---to my eyes---distributed quite peculiarly.

2) Treated the records as being independant (I know William knows this, but for some other folks: Surface temperature records are correlated across fairly substantial distances---a few hundred km. This is what makes paleoreconstructions possible, and what makes it possible to initialize global numerical weather prediction models with so few observations.)

3) Ignored that we do expect, and have reason to expect that the warming will be higher in higher latitudes

4) Ignored that the wealthy countries are at higher latitudes

Hence my calling it fooling around rather than work or study. He was, he said, submitting that pile of tripe* to a journal.
*pile of tripe being my term, not his.


His main conclusion was regarding climate change---namely that there isn't any. His secondary conclusion was that climate people studying climate data were idiots. Neither of those is a statement of economics, so my knowledge of economics is irrelevant (though, in matter of fact, it is far greater than his knowledge of climate; this says little, as his displayed level doesn't challenge a bright jr. high student.).

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You know, the more prominent and angrier "sceptics" like McLean/Carter, McKitrick/Macintyre, and Watts are really starting to dig themselves into pretty deep holes now with the quality of the papers they are producing.

The journal editors must be tearing their hair out with the junk being submitted to them.

On top of all the other problems, it's hard to justify a causal connection between higher incomes and higher temperatures. I hope no one is dumb enough to posit that money itself emits heat.

Presumably, McKitrick thinks the relationship is due to the urban heat island effect. But they have urban areas in the tropics too, and they've been growing much faster over the last half century than cities at higher latitudes. At any rate, this is a testable hypothesis that has been tested and found wrong.

So even without the bungled calculations, even without a spurious correlation, even without a very obvious alternative explanation for why these things might be correlated, the mechanism that McKitrick needs to conclude that there's no warming has itself been falsified. Just how many layers of wrong can one paper achieve?

I hope no one is dumb enough to posit that money itself emits heat.

Clearly the real reason economists care about the velocity of money and friction in the economy is the physics of climate change - because the faster you go and the more friction you have the more heat is generated ;-)

By Lotharsson (not verified) on 06 Apr 2010 #permalink

Pick, pick, pick!

Come on, it's no worse an error than those NASA engineers who neglected the difference between miles and kilometres for the Mars ExplorerExploder.

By David Irving (… (not verified) on 06 Apr 2010 #permalink

I hope no one is dumb enough to posit that money itself emits heat

Well I've got a tenner burning a hole in my back pocket, does that count?


Am I reading McI's assumptions about correctly?

"..correlations of temperature trends with economic indices are spurious..."

It's well... nuts?

By Watchingtheden… (not verified) on 06 Apr 2010 #permalink

Reminds me of when NASA mixed up metres and feet and one of their missions went wildly off course.

David Irving,
so, you are basically saying that engineering practices need to be audited but scientific practices not, because science is self-correcting? I guess I agree!


Of course, McKitrick's scientific technique of confusing radians with degrees has been audited by the self-proclaimed Climate Auditor Steve McIntyre, but unfortunately McIntyre's dog ate up his audit report... or perhaps the whole radians/degrees screw-up was part of the whole 'auditing' effort in the first place.

By stepanovich (not verified) on 09 Apr 2010 #permalink


Science is "self-correcting", in its peer-review and in its true replication (as opposed to the 'auditors' desired duplication) by independent groups.

Applied engineering does not normally involve submission for publication in a journal, or redesign by independent teams, and hence auditing, where appropriate, is required.

So both disciplines have their own processes for checking the veracity of their outputs. I guess that in your questioning you are confabulating different paradigms of operation.

By Bernard J. (not verified) on 11 Apr 2010 #permalink

Bernard, that was exactly the point I tried to make in my comment to DI.

You have got it badly wrong in quoting Schmidt. Schmidt made two elementary errors. First he confused autocorrelation in the dependent variable of a regression - not necessarily a problem, just a feature of the data - with autocorrelation of the residuals, which is a problem. The McKitrick analysis does not have autocorrelated residuals. Second Schmidt did not seem to realise that his estimated coefficients were outside the range which he himself implied they needed to be in to refute Mckitrick. And the journal concerned refused to publish a reply pointing this out. Anyone statistically competent who reads both Schmidt and the McKitrick reply will soon see who is right.