Wednesday, 4 March 2015

The logical basis for climate scepticism

I will try to avoid too much navel-gazing on this blog, but I think it’s important to define what’s being discussed.

Like many others, I came to scepticism over a period of time. The main claims I noted were:

·         Carbon dioxide concentration in the atmosphere was increasing dangerously due to mankind’s “addiction” to using fossil fuels;
·         The danger of increasing CO2 concentration was that it increased atmospheric temperature due to “the greenhouse effect”. The temperature increase, in turn, will cause dangerous sea level rise;
·         The global warming causes an increase in “extreme weather and climate events” such fewer extreme cold events, more extreme heat events “more heavy precipitation events”;
·         Warming is primarily caused by increased CO2 concentrations;
·         The oceans are “acidifying”;
·         By 2100 the average temperature of the Earth will rise by between 0.3 and 4.8 degrees Celsius when compared to the average temperature in the years 1986-2005.

These are paraphrased from Fifth Assessment Report (AR5) by the Intergovernmental Panel on Climate Change (IPCC). This organisation is owned and operated by the UN and is charged with reviewing the scientific literature to “prove” human induced, dangerous, global warming. Not surprisingly, it does just that.

All of these claims are made with modifiers like “high confidence” or “medium confidence”. Normally, in a scientific paper, a statement like “the item was measured at 10 ± 2 with 95 % confidence” has a specific, statistical meaning. It reports that the measurement is accurate to within one standard deviation of the mean of 10 and, if the measurement was repeated, 95% of the measurements would lie between 8 and 12.

The IPCC’s measure of confidence is measure of feelings of the authors and is not about the confidence of measurements.  This, I feel, is seriously misleading.

My scepticism is based on the following:

·         The climate is an extremely complex interaction of the Earth’s atmosphere, its surface and the oceans. Meteorologist and father of modern chaos theory, Edwin Lorenz, in his book The Essence of Chaos tells us “[… [there is] promise for one-week forecasts, but very little hope for one-month forecasts, while two-week forecasts seemed to be near the borderline.” My study of chaos in the 1990s made claims of accurate production of weather or climate of tens or hundreds of years seem very unlikely.
·         Yes, CO2 is a green house gas. A molecule of CO2 absorbs visible light energy and then re-emits it in the infrared band. The infrared is absorbed by other gas molecules in the atmosphere, heating it slightly. The details of this process are complex and probably not fully understood. If atmospheric CO2 was doubled, there appears to be little disputing that the atmosphere would warm by about one degree, assuming nothing else changed. That’s a big assumption.  The something else is probably clouds. The scientific debate is whether more high or low level clouds would be produced. If more high level clouds are produced, then the warming is amplified.  If more low level clouds are produced, you know yourself, it would get cooler. Cloud science is anything but “settled”.
·         The links between temperature and extreme weather events is tenuous, at best. Blaming cold weather events on global warming is counter-intuitive.  One recent report suggests the number of tropical cyclones has actually fallen. The media, however, uses the human misery associated with natural disasters to push the global warming barrow.
·         The oceans are not acidifying.  They are basic, not acidic. The tiny change has made then a tiny bit less basic.  This is not the same as making them acidic. This claim appears to be made solely to frighten people.  People are afraid of acid.
·         The claim of what the average temperature will be in ten, one hundred or one thousand years is conjecture. It is probably unpredictable to any useful level of accuracy.

The last point raises another question:  How do you actually measure the Earth’s temperature to any level of accuracy? That would be hard enough right now, never mind ten, one hundred or one thousand years ago.  I’ll deal with this in further posts.

Finally, why is opposition to the conventional wisdom on global warming greeted with such virulent opposition? They are branded ‘deniers’, to put them in the same class as holocaust deniers.

Austrian professor of Musicology Richard Parncutt says people like me should be killed.  If I recanted, though, I could get away with life in prison.  The boldface in the following statemnt is his:

“If a jury of suitably qualified scientists estimated that a given GW denier had already, with high probability (say 95%), caused the deaths of over one million future people, then s/he would be sentenced to death. The sentence would then be commuted to life imprisonment if the accused admitted their mistake, demonstrated genuine regret, AND participated significantly and positively over a long period in programs to reduce the effects of GW (from jail) – using much the same means that were previously used to spread the message of denial. At the end of that process, some GW deniers would never admit their mistake and as a result they would be executed. Perhaps that would be the only way to stop the rest of them. The death penalty would have been justified in terms of the enormous numbers of saved future lives.”

David Suzuki just thinks we should be jailed. “What I would challenge you to do is to put a lot of effort into trying to see whether there’s a legal way of throwing our so-called leaders into jail because what they’re doing is a criminal act,” said Dr. Suzuki, a former board member of the Canadian Civil Liberties Association.

Blogger Matt Walsh says we can live, just not work, teach or hold office. “…climate deniers should be banned from teaching, voted out of office, and probably fired from any other job they might hold. Seriously, I can’t hardly believe that anyone could be so foolish and so delusional as to be a climate denier. ”

Why all the angst? Why is questioning the “science” so threatening? Why is the debate always about the person and seldom about the science?

In future posts I intend to review what’s known, and perhaps what’s not, about Earth’s temperature.  I’m particularly intrigued with how you measure such a thing and how accurate the measurements are.

1 comment:

  1. This is a useful examination -- much better than "the basics are settled" claims. Thank you for some facts and a rational discussion.


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