The chemistry is pretty straightforward (I'm told) and it is a near
certaintly that humans are contributing to global warming through greenhouse
gasses as well as deforesting. The real issue, as you point out, is that we
don't know what would be happening if humans were not contributing. We
could be a small part of the problem or a large one, there is no way to
know. Climate data is so chaotic that it is difficult to filter the signal
from the noise.

Of course, there are other good reasons to be more efficient with fossil
fuels besides global warming.

Mike
MU-2


"Denny" wrote in message
oups.com...
We have been in "global warming" some 20,000 - 30,000 years now and the
"warming" continues apace and on schedule... Being that there was no
industrial activity, CFC spray cans, or SUV's, around some 20,000 -
30,000 years ago when the latest ice age reversed itself, global
warming replaced global cooling, the glaciers began retreating, and the
sea began rising, I doubt that a science based connection between
modern activity and global warming can be established with any degree
of verifiability or certainty... Of course, those who are emotionally
invested in the Kyoto Treaty, etc. and/or have an agenda will totally
ignore the scientific fact that we have been in a state of massive
global warming for more than 20,000 years, not just the last 150 years
since the industrial revolution...

Another pertinent point is that the ice age (our ice age with a glacial
moraine just a half dozen miles from where I sit) just past is simply
the most recent one in a sequence of some 30 to 50 ice ages covering a
span in excess of one quarter of a billion years.... Which company or
government do we blame for the previous 30-50 global warmings?

cheers ... denny