So, lets look at this factually...

In recent history, atmospheric CO2 levels have been at their lowest levels
in the entire history of the planet. It has been as low as about 150 ppm.
In recent history, it has been steadily climbing toward 300 ppm, presumably
due to human activity, but there has been a fair amount of volcanic activity
in recent years which also contributes large amounts of CO2.

Given the fact that during the age of the dinosaurs, CO2 levels were up
around 1,000 to 2,000 ppm, this recent CO2 rise is rather insignificant by
comparison.

Also, historical global temperature data shows that the earth has a
bi-stable average temperature (bouncing between 12C and 22C). The average
temperature of the earth is currently at the low bi-stable point, but
throughout most of the earths history, the temperature was at the high
bistable point. The last time that the earth had the current combination of
low CO2 and low average temperature was about 300 million years ago.

There is a nice historical summary graph that shows both atmospheric CO2
levels and average temperature that is available at
http://www.clearlight.com/~mhieb/WVF...s/image277.gif

Dean