4. Earth's temperature changes, then CO2 follows.
In 1999, more than a decade after the "manmade CO2 is the major cause of global warming" hypothesis became popular and many prominent politicians and academics had taken strong public positions in favor of that view, a startling discovery was made and came to light that atmospheric CO2 changes followed, not caused, temperature changes (see figure below). This was a paradigm changing discovery because the cause of climate change, which had been assumed to be CO2, was now revealed to be following, not causing climate change. Yet, those who had declared so boldly that man was committing another sin against nature try to play down the significance of the discovery. Even those who made the discovery were almost apologetic in their release of the information. After all, we now had a generation or more that had been taught that almost anything humans did was bad for the planet and this included our school children, now grown up, as well as teachers and professors who had taught only one view of the subject to their classes for years and years.
The push was either to prove it wasn't true or to minimize the significance that changes in atmospheric CO2 were not the initial cause of temperature changes. So they moved to the "well, it still causes positive feedback or amplifies the temperature change" which in the case of warming had been caused by a (shock!) naturally occurring event. It goes like this; temperature rises which then causes a rise in CO2 , presumably released from the oceans, and that additional CO2 causes a rise in temperature, which then causes a release of still more CO2 and on and on. This they say could lead to runaway global warming and roast the planet. The problem is, this runaway that they were and still are predicting, has never occurred, at least not in the last 500 million years of Earth's temperature history, even though naturally occurring CO2 levels have been as high as 7,000 parts per million versus the warming catastrophists' predictions that a simple doubling or less of our current 400 ppm will cause runaway warming. Despite the real world, empirical data, the logic seems to be lost on those who want to believe that man, once again, is the culprit. We concur that man has been the culprit many times and many ways on environmental issues but in this case, from what we now have learned regarding CO2 's influence on Earth's plant and animal kingdoms, man's activities causing a rise in airborne CO2 appears totally beneficial. Remember, a cause does not follow an effect.