Really. And what are climate changes for global warming based on? The temperature as recorded in various cities for the last 100 years....? Or computer models? Or both?
That is why the evidence that global warming is actually occurring is at best sparse. The temperature records are inaccurate and of very short duration. Trying to extrapolate 150 years of wildly inaccurate data over a time span of 3 billion years or so would be like me viewing a Polaroid picture of you at 3 P.M. in 1960 (assuming you're that old, of course) and trying to predict with confidence what you'll be wearing a 7 P.M. on April 3rd, 2031. Computer models are useless since there are too many parameters that are quite simply guesses (and many parameters that aren't even included in the models). Guesses are nothing more than personal prejudice of the scientist designing the model.