Robert, thanks for the reply. I agree that science has yet to completely verify that man/machine is contributing to the changes going on with the planet. I agree with Gene that saying it's "possible" will upset the those on the far eco-left but to completely deny it like the far industy-right is equally foolish.

Action - Reaction is a fact. Pumping chemicals into our air/water/dirt has consequences.

Like most things in life I'm sure the truth is somewhere in the middle.
I hold out hope that we discover the truth & find a healthy/prosperous balance.

As for Al Gore I'm no more a fan of him than I am a fan of George W.