Paul Krugman has long been fond of hyperbole, accusing for example bearish economic forecasters of being “evil” and economists who deny the link between deficits and interest rates of being “ideological and non-serious” – only to later himself issue bearish economic forecasts and deny the link between deficits and interest rates, illustrating that while he is fond of hyperbole, he is definitely not fond of logical coherence and consistency.

Now he is on the hyperbole path again, declaring people skeptical of Al Gore’s teachings to be guilty of treason against the planet.

Now, I readily admit to not being a climate scientist, but then again neither is Paul Krugman. But that doesn’t mean we can’t evaluate which scientists are more credible. Red Hot Lies: How Glob... Horner, Christopher C. Best Price: $0.49 Buy New $8.95 (as of 04:45 UTC - Details)

And contrary to what Krugman asserts, no consensus exists on the subject, with many scientists arguing against the view that human activities will have a significant climate impact, and that there is no evidence that whatever small effect exists will really have net negative effects for humanity.

So how should we determine which scientists are more credible? Well, by looking at the evidence. The Politically Incorr... Christopher C. Horner Best Price: $1.28 Buy New $7.79 (as of 05:35 UTC - Details)

The fact is that during the last 11 years, the Earth has been cooling, and not warming, despite increased carbon dioxide emissions. And while the Earth is warmer than a hundred years ago, we’re only talking about 0.7 degrees Celsius (1.3 degrees Fahrenheit). Temperatures are still below the levels seen during the Medieval warm period, and even more below several other historical warm periods during for example the Bronze age – periods when no significant human carbon emissions existed (it was essentially no emissions except for the carbon dioxide that we naturally exhale).

Is it really credible then to claim that after a century when radically higher carbon dioxide emissions was associated (empirically, something which in itself doesn’t prove causation) with a temperature increase of only 0.7 degrees, that unchanged emissions will increases temperatures by 9 degrees, as Krugman claims is likely? Even if he is using Fahrenheit, that would be equivalent to 5 degrees Celsius, 7 times larger than the increase the previous century.

And Krugman is simply lying when he claims that the planet is changing even faster than pessimists expected, because again temperatures have been falling since 1998.

Having had his Keynesianism embarrassed and discredited through his endorsement of a housing bubble, Krugman now apparently wants to move on to the climate debate. But just as in macroeconomics, Krugman commits treason against truth, prosperity and sound economics, which he during his previous career as a trade economist embraced.

July 1, 2009

The Best of Stefan M.I. Karlsson