Doubting the science can only be justified by asserting that the consensus is unreal, unreliable or unreasonable. This does not require all scientists to be liars; but it does require the vast majority of genuine experts to be either stupid, mistaken or mendacious.
Not only would such (implausible, improbable, or insidious) things be without precedent (and require an awful lot of people to be wrong or corrupt), there is also a clear precedent – in the tobacco industry – for the business-funded disputation of highly inconvenient science (which only required a few people to be corrupt in order to fool an awful lot of people). So, then, because I think it highly instructive – and since it is impossible to breach the confidentiality of someone who chooses to remain anonymous – Oakwood’s email to me is reproduced below (entirely without permission) with rebuttals included in bold text:
“You are entitled to your own opinions but not your own facts.” Yes, that applies to everyone. Here are a few facts: IPCC models did not predict the current temperature pause. If the IPCC has [now] said ‘because of what we know about the ocean’s massive heat capacity compared to the atmosphere, and the potential for aerosols from growing economies such as India and China, a 15 to 20 year pause is possible’. Of course, they didn’t say that [before], and only come up with the theory after the event. The IPCC do not do the modelling; they merely synthesise the results and summarise the implications. This is therefore statement of belief in either widespread scientific incompetence or political conspiracy. Furthermore, since (1) ice continues to melt (at sea and on land); (2) sea level continues to rise; and (3) ocean pH continues to decline, warming has clearly not stopped. See also ‘How reliable are climate models’ and ‘Global Warming Has Stopped’ on SkepticalScience (SkS). Proxy temperature data studies cannot reproduce instrumental data for recent decades – when temperatures are at their highest. Therefore, we cannot rely on them to say anything about previous ‘high temperature’ episodes, such as the MWP. This is a complicated issue but this argument has been comprehensively and repeatedly discredited. For example, see ‘Response by Marcott et al’ on Real Climate (with links to other sources of info). As for the MWP, see ‘How does the Medieval Warm Period compare to current global temperatures?’ on SkS. While so much is made of the Arctic’s ‘record’ low, little is said about the Antarctic’s ‘record’ high, except ‘well that’s different’. Antarctica is geographically isolated and affected by the hole in the ozone layer but, despite this, the West Antarctic and the Antarctic Peninsula are warming as fast as the Arctic. See also ‘Antarctica is gaining ice’ on SkS. The IPCC finds NO convincing link between extreme weather events (floods, drought, hurricanes) and global warming. Their best is ‘medium confidence’ (for heavy precipitation). (More warm days and fewer cold days is not ‘extreme weather’, but simply a logical outcome of the fact temperatures rose over the 20th C). The IPCC has been repeatedly shown to understate all kinds of risk. Historical analysis of weather in the Northern Hemisphere has shown that extreme weather is becoming more frequent. Multi-decadal change like this cannot be explained without reference to human activity. IPCC and climate scientists have no idea when the pause will come to an end. Their ‘accurate’ models cannot tell them. This does not matter. Arguing that warming has stopped requires falsification of the evidence that increased atmospheric CO2 is the dominant factor. See ‘It’s not us’ on SkS. The 97% consensus includes most AGW-sceptics, including me. That is: CO2 is a greenhouse gas; its concentration has increased over the 20th C; it has very likely made some contribution to warming. This myth has been repeatedly debunked. This piece on the RealSceptic blog is the best source of information I have yet seen on how and why this argument is entirely bogus. There is general agreement amongst climate scientists that a doubling of CO2 on its own will create about a 1dgC rise. CO2 is not acting alone and it is the totality of change that is causing problems. Apart from that facet of reality, this is a very misleading argument, as explained by Michael Mann himself on the LiveScience blog. Anything more relies on the belief/assumption that positive feedbacks will significantly outweigh negative feedbacks. Ongoing change despite a pause in surface warming implies warming effects are outweighing cooling effects. But, we’ve had all these discussions before. But you cannot show any one of these facts to be inaccurate, except by appealing to ‘the consensus’ and making nonsensical statements about ‘believing all scientists to be liars’. No, Rick, the practice of science is not about saying: ‘If you disagree with me, you’re calling me a liar’. I have not called Oakwood a liar but, I must admit, he/she does seem to be remarkably incapable of accepting that he may be wrong. It’s about proper open debate. The fact that the vast majority of ‘sceptics’ are libertarians and/or free-market ideologues proves that the ongoing ‘debate’ is driven by policy implications not any residual uncertainty regarding science. See this excellent essay by Stephan Lewandowsky on The Conversation blog. While still a minority, there are plenty of climate scientists and experts who do not believe AGW is a major threat. For this to be valid the pool of “climate scientists and experts” would have to be broadened to include all kinds of scientists whose expertise is not relevant. Since we do not generally allow this when discussing evolution or cosmology, why should we do it for climate science?
Of course the answer to that final question is that, as with evolution and cosmology, some people are ideologically opposed to accepting the nature of reality.