So much for the tobacco industry and its manufactured controversy. What about the climate change ‘controversy’? How is it different? It isn’t. It’s exactly the same.
Let’s look at some history. In the 1824 it was discovered that atmospheric CO2 produced an insulating effect, the ‘greenhouse effect’. By the end of the 19th century it had been proposed (and scientifically demonstrated), that an increase in atmospheric CO2 would warm the planet. This was recognized as significant, since the Industrial Revolution was in full force and it was well known that atmospheric CO2 levels would increase as a byproduct of human industries. However, back in those days it was considered that this increase in temperature would be slow and gradual, and that it would even have beneficial effects. Now, we know different.
By the 1930s, it was discovered that the US and the North Atlantic had warmed significantly. The significance of this was almost completely overlooked, but Guy Stewart Callendar (an engineer), interpreted this as the commencement of Anthropogenic Global Warming AGW). Like Arrhenius before him, Callendar thought that the effects would ultimately be positive.
However, the estimates of Arrhenius and Callendar were considered largely inconsequential. Scientists did not believe that CO2 could be produced by human activity in quantities which would result in significant global climate change, still less widespread negative effects. In any case, there were too many other variables to take into account before accurate predictions could be made. Unfortunately even the estimates of Arrhenius and Callendar underestimated completely the rapacious appetite of human industry and its staggering capacity to produce destructive waste.