In the midst of a radio interview the other day, on Vancouver's CFAX, a thoughtful caller phoned in to suggest that I was being taken in by a conspiracy of scientists, all of whom are promoting the notion of climate change because it's a fertile area of research. The caller suggested that the "consensus" in climate science is limited to researchers who take money from government; he said they're all touting a climate crisis because that's the best way to keep the research funds flowing.
This is an idea made popular by the relatively libertarian think tanks like the George C. Marshall Institute -- groups that believe anything to do with government is necessarily corrupt, inefficient or otherwise wrongheaded. It's an effective message: everyone harbours some degree of hostility toward government, so tying climate researchers to that unpopular entity is useful in undermining the credibility of the climate change warning.
On the radio, it left me to argue that my conspiracy theory (that highly consumptive industries are sowing doubt about climate change irresponsibly) is better than the caller's conspiracy theory (that scientists, addicted to government funding, will say anything to keep the money coming in).
Let me back away from that argument, which I think is unhelpful. Instead, I think it's better to look closely at the credentials and motivation.
First, compare the credentials of those who are making the case for climate change, as opposed to those who say that the outrageous recent weather events are a cosmic fluke that we can ignore at no cost. You will find, overwhelmingly, that the world's foremost climate scientists are arrayed on one side, and a bunch of second tier "scientists" (mostly industry-funded economists) are lining up on the other. I think economists are swell -- terribly helpful in making economic policy. But going to an economist for climate advice would be like calling an electrician to fix your sink.
Second, on the question of motivation, when the most powerful administration in the world is determined to deny that climate change is an issue, don't you think that self-serving scientists would be better off coming up with research projects that support the administration's position? There is, you have to admit, a possibility that the best scientists in the world agree on the risk of climate change because the risk is real -- in fact, undeniable. There is also a possibility (you have to admit) that think tanks that depend for their survival on donations from big industry might twist their own findings to support their favourite industry's position.
So, keep an open mind to all conspiracies, check everyone's references -- and follow the money. That, I think, will give you the best change of arriving at a reliable conclusion.