Forgive me IPCC, for I have sinned…

‘Call me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: humans are almost entirely the cause.’

So said Professor Richard A Muller in an op-ed for the New York Times on Sunday. Muller’s apparent Damascene conversion is the result of the Berkeley Earth Surface Temperature (BEST) project he founded with his daughter Elizabeth. In the NYT article, he claims that the BEST project shows ‘the average temperature of the Earth’s land has risen by two-and-a-half degrees Fahrenheit [about 1.5 degrees Celsius] over the past 250 years, including an increase of one-and-a-half degrees [about 0.8 degrees Celsius] over the most recent 50 years. Moreover, it appears likely that essentially all of this increase results from the human emission of greenhouse gases.’

There has been much rejoicing among eco-commentators. Leo Hickman in the Guardian declared: ‘So, that’s it then. The climate wars are over. Climate sceptics have accepted the main tenets of climate science – that the world is warming and that humans are largely to blame – and we can all now get on to debating the real issue at hand: what, if anything, do we do about it?’ However, Hickman had to add ‘If only’. Apparently, while Muller is the right kind of sceptic, some pesky critics just won’t accept the ‘facts’. ‘The power of his findings lay in the journey he has undertaken to arrive at his conclusions’, suggests Hickman, but clearly some people don’t get it.

It sounds like a powerful argument: someone who has publicly taken a position for a few years, before putting up his hands and effectively saying: ‘You know what? I was wrong, and my fellow travellers were wrong, and we should just fall into line with the mainstream view.’ The conversion analogy is a good one. Here, instead of the unbeliever falling at the preacher’s feet and accepting Jesus into their lives, no longer able to resist the power of the Lord, we have the sceptic allowing the IPCC to drive out the devil of climate-change denial from within his soul.

Except, like many a modern faith healer’s performance, there’s something dodgy about this widespread interpretation. For starters, Muller was hardly what you would call a climate-change sceptic. By and large, he has been very accepting of the IPCC’s view of the problem of climate change. His claim to being a sceptic seems to relate to his acceptance that the famous ‘hockey stick’ graph, which was the centrepiece of the IPCC’s 2001 report and suggested that current temperatures are unprecedented, was simply the product of some sloppy science.

But even then, Muller still put the case for the ‘consensus’ view. In 2004, he wrote: ‘If you are concerned about global warming (as I am) and think that human-created carbon dioxide may contribute (as I do), then you still should agree that we are much better off having broken the hockey stick. Misinformation can do real harm, because it distorts predictions.’ Another article from 2006 quotes Muller as saying that the odds that humans are to blame for global warming are ‘two in three’.

So, the most that we can say is that Muller has always suspected a significant human role in climate change, but he has also been honest enough to call out some poor research that appeared to support that view and to point out (approvingly, as it happens) that Al Gore used ‘exaggeration and distortion’ in his Oscar-winning film, An Inconvenient Truth. It is a testament to the closed-mindedness of the climate debate that these mild criticisms could qualify someone as climate sceptic.

Sceptic or not, it is far from obvious that Muller has made further discussion moot. There has been criticism that Muller’s methods in his new research are just not up to the job. Another climate researcher, Judith Curry – who was one of Muller’s colleagues on the first phase of the BEST project and who is a strong supporter of the IPCC’s general position – disagrees with Muller’s newfound certainty: ‘I have made public statements that I am unconvinced by their analysis. I do not see any justification in their argument for making a stronger attribution statement than has been made by the IPCC AR4.’ In other words, Curry thinks that the IPCC’s take on the matter – that most of the warming of the past 50 years is likely to be down to humans – is about right. Clearly, Curry is no sceptic either, but even she sees problems in Muller’s new claims.

Muller’s new conclusions are based on showing that the strong land-based warming in the temperature record is correct. (The oceans show a much slower rate of warming.) His research team has gone back over the temperature record to try to make sure that possible confounding factors – particularly the fact that weather stations may have been encroached by urban development and thus got warmer for reasons other than global climate change – are taken into account. Muller thinks he has settled the matter once and for all. Others disagree.

It’s worth noting in passing that Muller’s work has not been published in a peer-reviewed journal and that one reviewer, the hockey-stick critic Ross McKitrick who Muller has agreed with in the past, has now published the critical reviews of Muller’s work he provided for the Journal of Geophysical Research. Sadly, Muller seems to have ignored McKitrick’s criticisms. (For more on this, see Andrew Orlowski’s latest article in the Register.) Hypocritically, climate-change alarmists – who are normally utterly dismissive of anything that has not been published in a peer-reviewed journal – are only too happy to proclaim Muller’s results.

Moreover, another piece of research released in the past few days, led by meteorologist Anthony Watts, claims that the corrupting of those weather stations by urbanisation has gone much further than Muller and others have accounted for. Essentially, Watts – with the support of many volunteers – went out to check America’s weather stations and reclassify them according to the degree to which changes in their surroundings might affect their readings. Watts and his colleagues conclude that when these effects are taken into account, the rise in US temperatures has been only about half that suggested by the previous datasets.

But to a certain extent, this is all a false debate. There is no either/or. The leading climate sceptics all accept that humans have had some influence on the world’s climate. The argument is about how much human influence there is and what should be done about it.

Alarmists would argue that greenhouse-gas emissions are threatening to cook the planet and ultimately threaten humanity’s survival. At the very least, they see devastating destruction arising from global warming. For them, the only answer is the rapid decarbonisation of the world economy. Since the world is currently reliant on carbon-based fuels, this could mean an end to the drive for economic growth and the reorganisation of the economy and global politics. Anyone who disagrees is a ‘denier’. Some alarmists seriously suggest that debate should end now and anyone who continues to question the ‘consensus’ should be punished.

A few individuals aside, most climate sceptics think the world is moderately warmer than before, that humans have had some effect, but that most of the variation is natural and not particularly worrisome. Another band of sceptics – those who might be called ‘policy sceptics’, like Bjorn Lomborg and Roger Pielke Jr – broadly accept the IPCC’s view of temperature change and its causes. However, they think that the answer lies in devoting resources to technological development in the short term rather than a costly and probably futile attempt to decarbonise the world overnight. But even such policy disagreement is too much for the alarmists, who regularly pillory Lomborg in particular, yet it gets dressed up as ‘scientific fact’.

This last point rather gives the game away. What is really being contested is a political worldview in which human beings are seen as a blight on the planet. If some greens had their way, humanity would quietly shuffle off and leave Mother Earth in peace. More realistically, the aim of environmentalists is to reduce the human population and economic growth, so that a sustainable number of people live in a ‘steady state’ economy in harmony with the natural world. Such an outlook is romantic, in the worst possible sense, and downright misanthropic.

Whether the planet is warming or not, and whether it is human beings causing that warming or not, the only question that is worth answering is this: what is the best way forward for humanity? Trying to close down debate through censorious demands or through publicity stunts – which is effectively what Muller is attempting to pull off here – is the very opposite of a human-centred outlook.

Rob Lyons is deputy editor of spiked.