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

[Kyle Forinash <kforinas@ius.edu>]

 Rick

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.

kyle


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

--
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 'Before you open your mouth, just remember,
  the empty wagon rattles the loudest.'
         -- my dad

  kyle forinash   812-941-2039
  kforinas@ius.edu
  http://Physics.ius.edu/
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