-an update- I did some further research and found that the same scientific groups that say an increase in carbon-dioxide is mostly responsible for the increase in global temperatures...also said that during the ice-age periods of earth 'some' evidence shows that a decline in carbon-dioxide levels 'may' have contributed to cooling temperatures and the deepening of ice/glaciers.

So:
- more CO2 = higher temps and humans are to blame
- less CO2 = lower temps, but humans weren't industrialized 40,000 years ago so scientists say the evidence is 'inconclusive'

WHAT?!?!?!

Did you also know that we are currently just barely creeping out of one of the coldest periods of Earth's history dating back over 500 million years? And if you look at the graph of the global temperature history, we are following the 'curve'. But Al Gore will only show you a fraction of Earth's history to show you the huge 'jump' in temperature increases...wow! Thanks for the graph of 100 years out of the last 540million Mr. Gore!