We call it Riding the Gravy Train:
I devoted six years to carbon accounting, building models for the Australian government to estimate carbon emissions from land use change and forestry. When I started that job in 1999 the evidence that carbon emissions caused global warming seemed pretty conclusive, but since then new evidence has weakened that case. I am now skeptical. [...] I was on that gravy train, making a high wage in a science job that would not have existed if we didn’t believe carbon emissions caused global warming. And so were lots of people around me; there were international conferences full of such people. We had political support, the ear of government, big budgets. We felt fairly important and useful (I did anyway). It was great. We were working to save the planet!
But starting in about 2000, the last three of the four pieces of evidence above fell away. [...] There is now no observational evidence that global warming is caused by carbon emissions. You would think that in over 20 years of intense investigation we would have found something. For example, greenhouse warming due to carbon emissions should warm the upper atmosphere faster than the lower atmosphere — but until 2006 the data showed the opposite, and thus that the greenhouse effect was not occurring!
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