Interesting essay from "Jerome Ravetz, of Oxford University in the UK. Mr. Ravetz is an environmental consultant and professor of philosophy of science best known for his books challenging the assumptions of scientific objectivity, discussing the science wars and post-normal science. Read more about him at his personal web page here, his Oxford page here, or at his blog the Post-normal Times."
We can begin to see what went seriously wrong when we examine what the leading practitioners of this ‘evangelical science’ of global warming (thanks to Angela Wilkinson) took to be the plain and urgent truth in their case. This was not merely that there are signs of exceptional disturbance in the ecosphere due to human influence, nor even that the climate might well be changing more rapidly now than for a very long time. Rather, they propounded, as a proven fact, Anthropogenic Carbon-based Global Warming. There is little room for uncertainty in this thesis; it effectively needs hockey-stick behaviour in all indicators of global temperature, so that it is all due to industrialisation. Its iconic image is the steadily rising graph of CO2 concentrations over the past fifty years at the Mauna Loa volcano in Hawaii (with the implicit assumption that CO2 had always previously been at or below that starting level). Since CO2 has long been known to be a greenhouse gas, with scientific theories quantifying its effects, the scientific case for this dangerous trend could seem to be overwhelmingly simple, direct, and conclusive.
In retrospect, we can ask why this particular, really rather extreme view of the prospect, became the official one.