"It's been scientificaly and historicaly proven that planet earth has periods of global warmings and coolings every thousand years. The human involvement has nothing to do with it. "
The fact that the planet has warmed and cooled in the past does not prove that humans are not responsible for warming this particular time.
But it makes a hell of a case that Al Gore and his friends have yet to DISprove.
Natural or caused by mankind?
I'll place my bet on millions of years of climate history than some dubious computer models that it's natural.
The fact that the planet has warmed and cooled in the past does not prove that monkeys won't fly out of my butt.
The fact that the planet has warmed and cooled in the past does not prove that humans are not responsible for warming this particular time.
I can see your point, but considering the communist background of the people behind the "global warming" movement, one should not overlook the alterior motives of those who preach "global warming" as a manmade phenomenon.
Look! They even chose Vladimir Ilych Lenin's birthday for their "Earth Day" celebration. The enviromentalists abviously have a hidden agenda behind their movement.