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

["Dr. Richard Tarara" <rtarara@saintmarys.edu>]

----- Original Message ----- 
From: "brian whatcott" <betwys1@sbcglobal.net>


>  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" and 
> > then you go on to say how the results are not reproducable "100% of the 
> > time". I would characterize that as not rising out of the noise. /snip/
> > 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 not 
repeatable?  However, this is probably the nature of beast when we try to 
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 all 
dynamic models.  That is, the models themselves are constantly being updated 
and fed new data.  That's how it should be, but when somebody counters with 
a question about why this or that has or hasn't happened when predicted by 
the models and the answer comes back 'the current conditions are consistent 
with the model' (or something along those lines) is this 'consistent' with 
the old model or with the updated model that has recently been fed the 
particular data or conditions that might be in question?  Ultimately then 
the question becomes just how predictive the models really are.  How much 
should we rely on today's models say for 10 years hence.  Turned around, how 
accurate were the predictions of 10 years ago.  Of course this gets 
complicated by advances in the science and the computers such that we might 
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 with 
way many (too many?) variables!

Rick

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Richard W. Tarara
Professor of Physics
Saint Mary's College
Notre Dame, IN
rtarara@saintmarys.edu
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Free Physics Software
www.saintmarys.edu/~rtarara/software.html
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