Obviously, something else was happening that had greater significance for climate change than CO2 variation. The historical record of climate change shows that the "something else" has happened hundreds of times before, and that increased CO2 followed temperature increases by roughly 800 years.
The reason for that is simple and clear. Climate change, which for hundreds of thousands of years has fluctuated primarily with solar cycles combined with orbital variations, produces warming periods which in turn increase water temperature and cause the release of enormous quantities of CO2 from the oceans. The historical record also shows that temperatures have then fallen while CO2 levels were still elevated.
The following paragraph, from "Global warming zealots are stifling scientific debate," addresses the shortcomings of computer models. Read it, then read the entire article by clicking here.
Since the beginning of time, climate has always changed. It has warmed and cooled faster than any contemporary change. Nothing happening at present is unusual. The atmospheric carbon dioxide content in the past has been hundreds to thousands of times the current figure and the world did not end. Quite the contrary — life thrived. Computer models are models, albeit primitive. They are not predictions, they are not scenarios. They don't do clouds. They don't do turbulence. They don't do unseen submarine emissions of greenhouse gases. They deal only with greenhouse gas emissions from volcanos in times of little volcanic activity. They don't do starbursts, which have probably given us the greatest climate changes on Earth. They don't do variations in cosmic ray fluxes, which produce clouds in the lower atmosphere. They don't do mountain building, plate tectonics and closing or opening of seaways, which have profound effects on climate.