Scientific Proof and Falsifiability
By Dr Timothy Ball
By Dr Timothy Ball
They claim the climate science is over – the evidence is in
and the theory that humans are causing global warming and climate change is
proven. The statement, promoted by those with a clear political objective like
Al Gore must originate from a scientific source. Certainly the most recent
Intergovernmental Panel on Climate Change (IPCC) Report (the Fourth Assessment
Report abbreviated as FAR or AR4) provides a basis. Their claim of certainty is
based on computer model outputs, which they claim provide a 90% certainty that human
CO2 is causing climate change. A more important question is did science ever
begin?
A major problem with the IPCC claim is the level of science
used to create the model. The standard test for a model is validation, which
requires demonstration of the ability of the model to re-create known
conditions. In the case of climate this means accurately reproducing the
climate conditions of a particularly distinctive and well-documented climate
such as the most recent buildup of continental ice during the Pleistocene. More
recently there are the Medieval Warm Period (MWP) from approximately 900 to
1300 A.D., and the cool period known as the Little Ice Age (LIA) from
approximately 1450 to 1850 A.D. In fact, none of the computer climate models
have been validated.
Traditionally, this was referred to as hindsight
forecasting. It argues that if a model cannot create past climates it cannot
predict future climates.
There are two important concepts identified here; the role
of validation of a theory, and a basic definition of science as the ability to
predict. Both are part of a larger debate about science and scientific method
that have surprisingly few changes through history. Francis Bacon (1561 –1626)
formalized the scientific method that goes back to Aristotle. This involved
what is generally defined as Deductive Reasoning. You start with a hypothesis,
which is a tentative explanation for an observation, phenomenon, or scientific
problem that can be tested by further investigation.. Observations are then
made to test the hypothesis, which is either confirmed or rejected. More
correctly it is not rejected, but the null hypothesis is established.
Deductive Approach:
Hypothesis – Theory – Observation – Confirmation.
The second general form of approach is called Inductive
Reasoning. Here you move from general observation to determining a pattern from
which an hypothesis is drawn and a theory evolves.
Inductive Approach:
Observation – Pattern – Hypothesis – Theory.
In 1919 Karl Popper began to question the validity of
Inductive Reasoning by asking two questions as he explained in an article
titled “Science as Falsification” published in 1963. “When should a theory be
ranked as scientific?” and “Is there a criterion for the scientific character
or status of a theory?” http://www.stephenjaygould.org/ctrl/popper_falsification.html
Recently I wrote an article in which I identified a major
flaw with the theory of human-induced global warming or as it is commonly
abbreviated, anthropogenic global warming (AGW). One critic accused me of using
the entirely incorrect Popperian
falsification approach. Popper advanced the idea that no matter how many
supporting examples there were for a theory it only required one to falsify it.
This meant that any theory should be disproved rather than proved. In the 1963
article Popper updated and summarized his 1919 conclusions. Item 5 says, “Every
genuine test a theory is an attempt to falsify it, or to refute it.” However,
he promptly modifies the statement, “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.” This statement
appears applicable to the current anthropogenic global warming theory (AGW).
A major reason why it is less testable than others is
because it does not follow either the deductive or the inductive reasoning
approach. The most likely cause of the problem is the absolute dependence call
for theory on computer models.
They are deductive because they move from the more general,
which is the model itself, they are inductive because the model provides the
observations from which the theory is developed. They are inductive because the
model is derived from observations. However, the observations are inadequate
for the construction or to determine the pattern from which the theory must
evolve.
It is much easier to test the model if we assume it best
fits the deductive reasoning approach. This begins with a hypothesis that
humans have become a major cause of climate change and leads to the IPCC
climate change theory. These include that;
1. CO2 is a greenhouse gas and causes the surface to be
heated by the atmosphere in addition to the direct heating from the Sun.
2. If the level of CO2 in the atmosphere increases global
temperature will rise.
3. CO2 in the atmosphere will increase because of the
growing contribution from human activities.
If we apply Popper’s falsifiability to these assumptions
then AGW fails at the third stage of the deductive approach. Observations in
all records of any duration for any time period show that temperature increases
before CO2 increases, contradicting assumption 2. Despite this evidence all
models continue to use the assumption. It is not surprising therefore that the
hypothesis in the form of the models also fails the fundamental definition of
science because their predictions are consistently wrong. It is also not
surprising considering the lack of validation.
If either the deductive or inductive method was being used
the prediction failure should lead to correction of the models. They try to
make the model fit the observations, but it only so they appear to simulate
reality. It does not include reassessing the assumptions. Remove assumption 2
and the entire theory collapses. The question is why won’t they do what is
scientifically correct?
Popper provides an explanation in item 7 on his list. This
reads, “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.” This leads back to a comment Popper makes at the
beginning of his 1963 essay. “The problem which troubled me at the time was
neither, “When is a theory true?” nor “When is a theory acceptable?” My problem
was different. I wish to distinguish between science and pseudoscience; knowing
very well that science often errors and that pseudoscience may happen to
stumble on the truth.”
The short answer to the question, did science ever begin
with the climate theory that humans are causing warming or change, is no. The
approach was neither deductive nor inductive. The theory was transposed to a
model built on inadequate data or understanding of the mechanisms of climate.
Because the models were not validated they are inadequate as models let alone
as the basis for a theory. They also failed to make accurate predictions, a
very basic definition of science. Finally, they fail as science and fit
Popper’s definition of pseudoscience because instead of adjusting to failures
they continue to blindly and dogmatically pursue a failed hypothesis.
10/2008
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