[Phys-L] Re: positive feedback loops (was global warming)

[dtmarx at ILSTU.EDU (David T. Marx)]

The answer is that no one knows.  The models that do include feedback make it a positive one and
thus get the scariest results, as you suggest.  The chemistry of epoxy resin is much easier to
understand than the complex system that is the Earth's climate, however.

This morning, while walking through a nearby supermarket, I happened upon Michael Crichton's book
"State of Fear" that started this thread.  The points he makes in his personal epilogue are right
on target.  He and I are very much in agreement on the present situation and future of global
warming.  There is no axe to grind, just an honest assessment of the science of climate change.

Take care,
David Marx

> As one who has witnessed firsthand a rather striking
> thermal positive feedback loop (by accidentally adding
> way too much hardener to epoxy resin), I wonder
> whether any of the models which relate atmospheric
> temperature increase to human activity postulate this
> sort of behavior. If there is a strong possibility
> that such a feedback situation could/does exist, then
> it seems very dangerous indeed to wait for solid
> proof. Once the temperature of the resin mix starts
> its rapid rise, smoke very quickly follows.
>
> OTOH, if most atmospheric scientists & climatologists
> believe that the feedback loop(s) are or will be
> negative (or neutral) in nature, then we can well
> afford to wait.
>
> John Barrere  University HS  Fresno, CA