One of the things I’ve tried to point out here is the emptiness of the categories and concepts that dominate reporting on the climate debate. In particular, the notion of ‘consensus’ has become so entirely divorced from its substance that those who invoke it often have no idea what it refers to. It is a ‘consensus without an object‘.

The idea that there is a scientific consensus, and a tiny opposing minority then informs coverage of the debate. These coordinates are forced over any story about the climate, which dares to raise the subject of the climate debate, rather than the inevitable doom. There are scientists, and there are sceptics, and never the twain shall meet.

But this polarisation exists much more in the heads of reporters than real life. The consensus is far more nebulous than many will admit.

Take BBC’s Environment Analyst, Roger Harrabin’s recent report on Nic Lewis’s research in the light of IPCC reports, for example.

‘Are the Climate Wars over?’ asks the presenter, introducing Harrabin… “We have reached the point now, where many climate sceptics are singing off the same hymbook as mainstream science over the effects of CO2..”, he claims.

Harrabin’s claim is brilliantly illustrated by Josh over at Bishop Hill.

It sounded like Roger thought sceptics were now changing their tune but clearly, with lower sensitivity, The Pause and no hope of any global policy harmony on the horizon, the strains that are coming from the alarmist camp now have much more of a sceptic air.

Indeed, and it has to be pointed out to Roger — other mistakes about his reproduction of Lewis’s research to one side — that the IPCC’s estimated range of climate sensitivity has changed, as is revealed by the AR5 WGI SPM [PDF]:

The equilibrium climate sensitivity quantifies the response of the climate system to constant radiative forcing on multi-century time scales. It is defined as the change in global mean surface temperature at equilibrium that is caused by a doubling of the atmospheric CO2 concentration. Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C (high confidence), extremely unlikely less than 1°C (high confidence), and very unlikely greater than 6°C (medium confidence)16. The lower temperature limit of the assessed likely range is thus less than the 2°C in the AR4, but the upper limit is the same. This assessment reflects improved understanding, the extended temperature record in the atmosphere and ocean, and new estimates of radiative forcing.

And the footnote:

No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies.

The consensus changed between AR4 and AR5. But does this bring sceptics and the consensus closer together than they were?

Other BBC staff clearly got Harrabin’s memo. Yesterday, the GWPF’s Benny Peiser then appeared on BBC News 24…

The interviewer said to Peiser:

If you look at the whole argument… If you look at the historical difference between [sceptics vs scientists] The sceptics have said initially there’s no warming, then they’ve said it’s not down to man, and now they do seem, you do seem to be coming more into line with the international body of thinking over what is going to happen in the future. […] Take Nic Lewis, leading sceptical scientist, recent report coming out with forecast figures that are very much in line with the UN’s.

But how much have the sceptics changed their tune in relation to the consensus?

Going through some old articles of mine, I found my review of Iain Stewart’s BBC series, Earth: The Climate Wars for Spiked in 2008 — six years ago. The series had been co-written by Naomi Oreskes.

After a section featuring Christopher Monckton and his views that much climate science was fraudulent near the end of episode two, Stewart said,

To me, such attacks are a sure sign that the scientific battle is over. And sure enough, perhaps the most surprising thing at the sceptic’s conference is what I heard at the keynote speech.

The film then shows Patrick Michaels taking the stage at the 2008 International Conference on Climate Change. Stewart continues…

For years, climatologist Pat Michaels has been one of the most vocal sceptics. And yet today he’s in surprising agreement with advocates {sic} of global warming. […] He accepts the globe is warming. But the truly astonishing thing is he also accepts that we are partly to blame. […] [to camera]: You know I’ve heard things here that’s really surprised me. I’ve heard things I really didn’t expect to hear climate sceptics to say. They say global warming is happening. Temperatures are going up. And that humans are somehow implicated in some degree. That’s amazing. Those issues, it looks like, are behind us.

Stewart had claimed, six years ago, that Pat Michaels — who is in the first division of the environmentalist’s demonology — had changed his mind about climate change. But as I reported at the time,

‘For years, climatologist Pat Michaels has been one of the most vocal sceptics. And yet, today, he’s in surprising agreement with the advocates of global warming’, said Stewart. Michaels is then shown giving his talk, saying ‘global warming is real, and in the second half of the twentieth century, humans had something to do with it’. But there is nothing surprising about Michael’s apparent turnaround, because it isn’t one. A 2002 article in the Journal of Climatic Research, authored by Michaels et al argued for a revision of the IPCC’s projections for the year 2100. Instead of saying that there would be no warming, the paper concluded that rises of ‘of 1.0 to 3.0 degrees Celsius, with a central value that averages 1.8 degrees Celsius’ were more likely than the IPCC’s range of 1.4 to 5.8 degrees Celsius. Hardly climate change denial.

The abstract of Michaels et al 2002 [PDF] is as follows.

Temperature projections for the 21st century made in the Third Assessment Report (TAR) of the United Nations Intergovernmental Panel on Climate Change (IPCC) indicate a rise of 1.4 to 5.8°C for 1990–2100. However, several independent lines of evidence suggest that the projections at the upper end of this range are not well supported. Since the publication of the TAR, several findings have appeared in the scientific literature that challenge many of the assumptions that generated the TAR temperature range. Incorporating new findings on the radiative forcing of black carbon (BC) aerosols, the magnitude of the climate sensitivity, and the strength of the climate/carbon cycle feedbacks into a simple upwelling diffusion/energy balance model similar to the one that was used in the TAR, we find that the range of projected warming for the 1990–2100 period is reduced to 1.1–2.8°C. When we adjust the TAR emissions scenarios to include an atmospheric CO2 pathway that is based upon observed CO2 increases during the past 25 yr, we find a warming range of 1.5–2.6°C prior to the adjustments for the new findings. Factoring in these findings along with the adjusted CO2 pathway reduces the range to 1.0–1.6°C. And thirdly, a simple empirical adjustment to the average of a large family of models, based upon observed changes in temperature, yields a warming range of 1.3–3.0°C, with a central value of 1.9°C. The constancy of these somewhat independent results encourages us to conclude that 21st century warming will be modest and near the low end of the IPCC TAR projections.

By the standards of IPCC TAR, Michaels was not outside the consensus in 2002. And by the standards of AR4 in 2008, Michaels was not outside of the consensus when Iain Stewart made his films. The only ‘surprising’ thing revealed — as the punchline — by the second of three episodes of Climate Wars is that Stewart was ignorant of the debate he was reporting on. He had begun his film with a preconceived idea about the climate debate, as one divided into two camps — sceptics and deniers — disagreeing about a single proposition: “climate change is happening”. And then, when he encountered the more nuanced reality, he imagined that it was sceptics who had changed their position. It was Stewart’s desire to frame the debate that led to his misreporting.

Harrabin tells me via email that there wasn’t enough time in a three-minute slot to cover the nuances of the debate. But Stewart, with his three-part series of hour-long episodes cannot make such a claim. And this error characterises so much BBC coverage of the ‘Climate Wars’. Unfortunately for Harrabin, who thinks the convergence of the sceptics and the consensus is new, and therefore an interesting development, the Climate Wars series and Michaels’ 2002 paper show that sceptics’ estimates haven’t changed much.

And the BBC’s treatment of climate sceptics hasn’t changed much either. It is surely a welcome thing that, be it on the Today Programme, or BBC News 24, or Earth: The Climate Wars, sceptics’ arguments at least get a little airtime. But the substance of those interviews, and the narrative around them, the editorial decisions about what is included from those interviews, and the questions asked are all informed by the same preconceived and false understanding of the debate, and the positions within it.

BBC journalists in particular trip over their own framing of the climate debate. They imagine it to be sharply divided, but when they discover nuance, they report a shift in positions with respect to the consensus, like the misconception of the Sun’s displacement through the sky leading to the misapprehension of a geocentric universe. They’re not reporting developments from climate science, or from the climate debate, just their own misunderstanding of what they see.