MaxedOutMama

Human thinking is not naturally rational. Rationality is a fragile, painstakingly constructed edifice that allows us to understand the world and manipulate bits of reality in ways that pre-technological, even the most civilized of pre-technological, beings could not begin to approximate. Yet to presume that what we have is immutable and invulnerable to the ravages of irrationality is dangerous.
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Math, which attempts to inculcate an approach based on precise rules and measurements to arrive at logical, consistent, and rigorously understood truths, is one of the foundational intellectual exercises of our civilization.
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In much the same fashion, attacking Science, the methodology of which is our greatest single intellectual and rational development, upon which all else that allows us to survive and thrive depends, is dangerous and promotes the kinds of illogical beliefs that Ed Morrisey documents so well.

SW, I think the result of the CO2-induced global warming hysteria has done more damage to the popular conception of science than anything else in the last 50 years. It's not so much that the theory now appears to be largely mistaken; that is completely understandable and no indictment of science given the state of our knowledge at the time it first became a public policy issue. We knew then that the historical record showed a strong correlation with CO2, which is indeed a greenhouse gas although a relatively weak one. Many a scientific theory has been proposed and gained relatively wide acceptance upon such evidence.

What is terrifying is that in the face of totally contrary evidence the theory is now gaining a cult-like passionate adherence, and that the popular dialogue has shifted from the idea of evidence being the foundation of the theory to the idea that some mythical "consensus" among scientists is what makes a scientific theory true. Scientific history is replete with examples of a scientific consensus in one decade being utterly overturned in the next decade or two by new evidence. To retain a culture which can use science to determine the factual framework upon which a rational public policy debate can occur, science must retain its ability to absorb new evidence and revise itself. An entire generation of younger people will grow up with this conception - that science is a matter of consensus rather than evidence - firmly fixed in their in their psyches. Furthermore, students are often being taught in science class that because this theory requires sacrifice and cooperation it is a "good" scientific theory.

We may laugh about the claim that fire has never yet melted steel, but the disconcerting reality that this "fact" could be so widely asserted and discussed in public and in the newspapers without an attempt to ascertain whether it is in fact true shows how far our public discourse has diverted from being one based on truth to one based on adherence.

The scientific method involves the following basic facets:

* Observation. A constant feature of scientific inquiry.

* Description. Information must be reliable, i.e., replicable (repeatable) as well as valid (relevant to the inquiry).

* Prediction. Information must be valid for observations past, present, and future of given phenomena, i.e., purported "one shot" phenomena do not give rise to the capability to predict, nor to the ability to repeat an experiment.

* Control. Actively and fairly sampling the range of possible occurrences, whenever possible and proper, as opposed to the passive acceptance of opportunistic data, is the best way to control or counterbalance the risk of empirical bias.

* Falsifiability, or the elimination of plausible alternatives. This is a gradual process that requires repeated experiments by multiple researchers who must be able to replicate results in order to corroborate them. This requirement, one of the most frequently contended, leads to the following: All hypotheses and theories are in principle subject to disproof. Thus, there is a point at which there might be a consensus about a particular hypothesis or theory, yet it must in principle remain tentative. As a body of knowledge grows and a particular hypothesis or theory repeatedly brings predictable results, confidence in the hypothesis or theory increases. (See also Lakatos.)

* Causal explanation. Many scientists and theorists on scientific method[attribution needed] argue that concepts of causality are not obligatory to science, but are in fact well-defined only under particular, admittedly widespread conditions. Under these conditions the following requirements are generally regarded as important to scientific understanding:

* Identification of causes. Identification of the causes of a particular phenomenon to the best achievable extent.
* Covariation of events. The hypothesized causes must correlate with observed effects.
* Time-order relationship. The hypothesized causes must precede the observed effects in time.

...the most popular - and the most straightforward - explanation of the direction of the causal relationship is the fact that in all cases, the CO2 concentration only changed its trend roughly 800 years after temperature had done the same thing. There have been many papers that showed this fact and incidentally, no one seems to disagree with it.

Every sane person knows that this detailed insight implies that the greenhouse effect couldn't have been among the most important effects. Not only the ice core data fails to provide us with evidence supporting the greenhouse theory of the climate; it provides us with strong evidence against it.
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Everyone who has basic understanding of feedback theory knows that what they talk about is a textbook example of a positive-feedback system, and if the climate were such a system, the mutually supportive interactions would lead to exponentially escalating temperatures in one of the possible directions. That's clearly not observed in the data and the positive-feedback hypothesis is thus falsified.

If the amount of carbon dioxide were doubled instantaneously, with everything else remaining the same, the outgoing infrared radiation would be reduced by about 4 Wm-2. In other words, the radiative forcing corresponding to a doubling of the CO2 concentration would be 4 Wm-2. To counteract this imbalance, the temperature of the surface-troposphere system would have to increase by 1.2°C (with an accuracy of ±10%), in the absence of other changes. In reality, due to feedbacks, the response of the climate system is much more complex. It is believed that the overall effect of the feedbacks amplifies the temperature increase to 1.5 to 4.5°C. A significant part of this uncertainty range arises from our limited knowledge of clouds and their interactions with radiation. To appreciate the magnitude of this temperature increase, it should be compared with the global mean temperature difference of perhaps 5 or 6°C from the middle of the last Ice Age to the present interglacial.

The so-called water vapour feedback, caused by an increase in atmospheric water vapour due to a temperature increase, is the most important feedback responsible for the amplification of the temperature increase. Concern has been expressed about the strength of this feedback, in particular in relation to the role of upper tropospheric humidity. Since the SAR, thinking about this feedback has become increasingly sophisticated thanks both to modelling and to observational studies. Feedbacks are discussed and assessed in Chapter 7. In particular, the present state of knowledge of the water vapour feedback is examined in Section 7.2.1.

Water vapour feedback continues to be the most consistently important feedback accounting for the large warming predicted by general circulation models in response to a doubling of CO2. Water vapour feedback acting alone approximately doubles the warming from what it would be for fixed water vapour (Cess et al., 1990; Hall and Manabe, 1999; Schneider et al., 1999; Held and Soden, 2000). Furthermore, water vapour feedback acts to amplify other feedbacks in models, such as cloud feedback and ice albedo feedback. If cloud feedback is strongly positive, the water vapour feedback can lead to 3.5 times as much warming as would be the case if water vapour concentration were held fixed (Hall and Manabe, 1999).

As noted by Held and Soden (2000), the relative sensitivity of OLR to water vapour changes at various locations depends on how one perturbs the water vapour profile; the appropriate choice depends entirely on the nature of the water vapour perturbation anticipated in a changing climate. The sensitivity is also affected by cloud radiative effects, which tend to mask the influence of sub-cloud water vapour on OLR. Incorporating cloud radiative effects and a fixed relative humidity perturbation (argued to be most appropriate to diagnosing GCM water vapour feedback), Held and Soden suggest that OLR is almost uniformly sensitive to water vapour perturbations throughout the tropics. Roughly 55% of the total is due to the free troposphere in the “tropics” (30°N to 30°S) with 35% from the extra-tropics. Allowing for polar amplification of warming increases the proportion of water vapour feedback attributable to the extra-tropics. Of the tropical contribution, about two thirds, or 35% of the global total, is due to the upper half of the troposphere, from 100 to 500 mb. The boundary layer itself accounts for only 10% of the water vapour feedback globally. Simulations incorporating cloud radiative effects in a doubled CO2 experiment (Schneider et al., 1999) and a clear-sky analysis based on 15 years of global data (Allan et al., 1999) yield maximum sensitivity to water vapour fluctuations in the 400 to 700 mb layer (see also Le Treut et al., 1994). In a simulation analysed by Schneider et al. (1999) extra-tropical water vapour feedback affected warming 50% more than did tropical feedback.

Most of the free troposphere is highly undersaturated with respect to water, so that local water-holding capacity is not the limiting factor determining atmospheric water vapour.