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Re: fHuman vs. natural influences on the environment

charliew@hal-pc.org (charliew) wrote:
>So what?  There is no big revelation here that a very large 
>system (the atmosphere) has a long process time constant (it 
>takes a long time to see a change).  This idea is common 
>knowledge to any process control engineer.

It is common knowledge to any process-control engineer that
a system reacts little to forcing functions above its cutoff
frequency.

The observation that the atmosphere reacts very substantially
to a forcing function with a period of 1 year proves that the
"long process time constant" is short even on human time scales.

> What about the 
>fact that this long response time can also be beneficial in 
>that sudden disturbances may have little or no impact?

This one sentence contains several faulty assumptions.  To
list a few:

1.)  It assumes the disturbance is a delta function which is
     never repeated.  A more accurate model would be a ramp
     function.

2.)  It assumes that the response time is long compared to
     the duration of the disturbance.  See above.

3.)  It assumes that the system is linear and stable.  The
     best data to date suggests that it is chaotic.
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