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Re: [Phys-l] Prof. Hal Lewis resigns from APS

Every study of ice cores and other temperature proxy that is compared with
atmospheric CO2 shows that temperature leads CO2 increase by hundreds to
thousands of years.


Hanson makes the argument in his "Grandchildren" book that we aren't
relying on computer models when we say we know CO2 will raise the
temperature. He says (I have not found the scientific paper) there were
natural experiments in the geological past that show warming driven by
CO2. One example he talks about (besides the feedbacks that pushed
climate out of ice ages) was the Paleocene-Eocene thermal maximum.
Hanson seems to think that a large injection of carbon into the
atmosphere (the cause of which is poorly understood) resulted in a sharp
6C global temperature increase.


----- Original Message -----
From: "brian whatcott"<>

On 10/12/2010 6:28 AM, LaMontagne, Bob wrote:
You seem to take it as an insult that I would say that "the serious
investigators have not found an effect that rises out of the noise"
then you go on to say how the results are not reproducable "100% of
time". I would characterize that as not rising out of the noise.
Bob at PC

Interesting fusion of the concepts of
significance and repeatability coming through here?

Of course one could counter with how significant is a result if it is
repeatable? However, this is probably the nature of beast when we try
talk about global climate.

Something that concerns me and the degree to which we are depending on
computer modeling to deal with the topic, is that certainly these are
dynamic models. That is, the models themselves are constantly being
and fed new data. That's how it should be, but when somebody counters
a question about why this or that has or hasn't happened when predicted
the models and the answer comes back 'the current conditions are
with the model' (or something along those lines) is this 'consistent'
the old model or with the updated model that has recently been fed the
particular data or conditions that might be in question? Ultimately
the question becomes just how predictive the models really are. How
should we rely on today's models say for 10 years hence. Turned around,
accurate were the predictions of 10 years ago. Of course this gets
complicated by advances in the science and the computers such that we
well expect today's models to be better than those of 10 years ago.
Still--models are just that, and climate models are extremely complex
way many (too many?) variables!


Richard W. Tarara
Professor of Physics
Saint Mary's College
Notre Dame, IN
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