"Steve Schulin" wrote in message
...
I agree that these are worth reading. For example the blue-ribbon panel
report often called the NAS Report from June 2001:

"Because of the large and still uncertain level of natural variability
inherent in the climate record and the uncertainties in the time
histories of the various forcing agents (and particularly aerosols), a
causal linkage between the buildup of greenhouse gases in the atmosphere
and the observed climate changes during the 20th Century cannot be
unequivocally established. The fact that the magnitude of the observed
warming is large in comparison to natural variability as simulated in
climate models is suggestive of such a linkage, but it does not
constitute proof of one because the model simulations could be deficient
in natural variability on the decadal to century time scale."

Hi Steve,

What would constitute proof for you that the large increase in temperature
this last century is largely caused by GHG emissions?

I ask you only because you just quoted this. I often wonder that, when
someone, quite correctly, states that there is no proof that CO2 is causing
this temperature rise. What are they waiting to see?

--
Coby Beck
(remove #\Space "coby 101 @ bigpond . com")