"...a computer model is only as good as the data which was put into it..."

Correct, Little Hawk. But even if the input data is correct, if the computer-model's underlying model is incorrect then its predictions will be incorrect. For example, if the underlying model is "each 1ppm increase in atmospheric CO2 concentration lowers the global temperature by 3degF", then input data of "atmospheric CO2 concentration will increase with time" results in the computer-model predicting falling temperatures.

I, btw (pace Little Hawk), deny that temperatures are increasing at present. There has been no "global warming" for a decade or more, now.