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Andre May7-07 07:23 AM

Black Swans and Global Warming
I wrote this to some friends who keep discussing posteriorities.

Black Swans; an essay about global warming refutation logic

By Andre

About the strikingly successful proofs of Einstein’s “risky” or “counter-intuitive” predictions based on the relativity theorems, Karl Popper observed:


“Now the impressive thing about this case is the risk involved in a prediction of this kind. If observation shows that the predicted effect is definitely absent, then the theory is simply refuted. The theory is incompatible with certain possible results of observation, in fact with results which everybody before Einstein would have expected. This is quite different from the situation I have previously described, when it turned out that the theories in question were compatible with the most divergent human behavior, so that it was practically impossible to describe any human behavior that might not be claimed to be a verification of these theories.

These considerations led me in the winter of 1919-20 to conclusions which I may now reformulate as follows.

1. It is easy to obtain confirmations, or verifications, for nearly every theory - if we look for confirmations.

2. Confirmations should count only if they are the result of risky predictions; that is to say, if, unenlightened by the theory in question, we should have expected an event which was incompatible with the theory - an event which would have refuted the theory.

3. Every "good" scientific theory is a prohibition: it forbids certain things to happen. The more a theory forbids, the better it is.

4. A theory which is not refutable by any conceivable event is non-scientific. Irrefutability is not a virtue of a theory (as people often think) but a vice.

5. Every genuine test of a theory is an attempt to falsify it, or to refute it. Testability is falsifiability; but there are degrees of testability: some theories are more testable, more exposed to refutation, than others; they take, as it were, greater risks.

6. Confirming evidence should not count except when it is the result of a genuine test of the theory; and this means that it can be presented as a serious but unsuccessful attempt to falsify the theory. (I now speak in such cases of "corroborating evidence.")

7. Some genuinely testable theories, when found to be false, are still upheld by their admirers - for example by introducing ad hoc some auxiliary assumption, or by reinterpreting the theory ad hoc in such a way that it escapes refutation. Such a procedure is always possible, but it rescues the theory from refutation only at the price of destroying, or at least lowering, its scientific status. (I later described such a rescuing operation as a "conventionalist twist" or a "conventionalist stratagem.")

One can sum up all this by saying that the criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.”
So let’s project these ideas on global warming. It is clear that confirming evidence is difficult to obtain for a risk less hypothesis, if we assume that greenhouse effect exists. Proving global warming as in excessive –dangerous-, due to natural positive feedbacks and caused by anthropogenic CO2 is a bit more challenging. This is as close as it can get to Poppers second observation about risky predictions. Non natural experimental models however “sophisticated” or the mere observation that the temperatures and the CO2 are rising together on occasions however, would not pass Poppers criteria for convincing evidence for that prediction.

Neither proof -of course- would be the ignorance fallacy or the fallacy of the restricted choice: “Global warming can either be caused by higher solar output or more greenhouse effect. The solar output is not higher, so it must be greenhouse effect, what else can it be?”

Nevertheless, the natural reaction of testing the hypothesis nowadays (as in attempting falsification) appears to be opening the restricted choice and focussing on presenting alternative mechanisms for the atmospheric warming in the past decades: It could also be solar particles, variation in cloudiness, land use, aviation, direct heat anthropogenic sources and UHI, natural weather patterns. Alternatively, one could challenge the “anthropogenic” element by questioning the fraction of human C2 production against natural sources. All those cases have been made with considerable efforts. However, those elements are not in the refutation criteria of Karl Popper and the result is having competing ideas, mutually vulnerable for refutation, and triggering both sites onto the seventh observation of Karl Popper, destroying the idea by an attempt to make it invulnerable for refutation.

A classic popular illustration of refutation mechanism (does not work in Australia) is the all-swans-are-white hypothesis, since millions are; but the hypothesis crumbles, if we find a single black one. Global warming has many white swans. The ice is melting - white swan. It's getting warmer - white swan, CO2 and temperatures have both risen roughly between 1975 and 1998, white swan. Ice cores white, Venus white, Paleocene Eocene Thermal Maximum (PETM) white; there is a body of white swan evidence in the IPCC reports. Oh occasionally there are incidents. Somebody found a grey goose and painted it white and it was called the hockeystick. The animal has been cleaned and it’s a grey goose again, proving nor disproving anything except for the determination to find white swans for some reasons.

How about real black swans? It appears that we need only one single occasion where the CO2 positive feedback on CO2 rise -the mainstay of the global warming hypothesis- is not present, while it should have.

Such a process has been demonstrated by Olavi Kärner and the missing positive feedback in the atmospheric processes. This could be considered a real black swan,

Karner, O., On nonstationarity and antipersistency in global temperature series, J. Geophys. Res., 107(0), XXXX, doi:10.1029/2001JD002024, 2002.

But it is beyond me why this swan only exists scantily at the webpage of its owner, whereas it should have been paragraph one of the IPCC summary for policy makers. Therefore it is recommended to testers of the global warming hypothesis, not to focus on proving competing hypotheses but concentrate on finding black swans and explain to the public why those destroy the catastrophic global warming idea. Suitable areas could be the empiric observations of the role of water vapour in climate modification compared in continental and maritime climates. Efforts are underway to demonstrate that the ice cores do not show positive feedback behaviour, as propagated, to explain the Pleistocene glaciation cycles.

Those black swans are needed first and only if they have done the job, then the scientifically sound searches for new hypotheses explaining the current warming, ice ages, the PETM, Venus, etc can be resumed

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