What exactly do they mean by consensus? Scientists, climate change and scepticism

The more environmentally fussbucketing parts of the left exploded into frothing excitement because a BBC TV programme on attitudes to science succeeding in portraying libertarian writer, James Delingpole in less than flattering terms. Now I like James Delingpole’s writing – it does what polemics should do, plays to the prejudices of its readers by simultaneously providing pithy attack lines for fans and winding up opponents. It is the football chanting of political writing.

However, the substance of the criticism is that James rejects the “consensus” around anthropogenic global warming (AGW). I gather that this is a terrible crime since James isn’t a “scientist”. Sir Paul Nurse – who is a scientist, asked him a killer question – and he stuttered and stumbled.

Nurse's interview with Delingpole was notable for forming a centrepiece to the programme, and because Delingpole complained he was stitched up on his blog, claiming that a good three hours of him being reasonable and cogent was edited out in favour of one scene where he looks like an idiot. To be fair, there are two scenes where he looks like an idiot. In one he explains that he never reads peer-reviewed scientific literature on the subject of global warming because "it's not my job". In the other, he condemns the scientific consensus on global warming – and consensus in general – as unscientific.

When Nurse presented him with a perfectly reasonable analogy about having cancer and choosing a remedy of one's own devising over the "consensus" treatment, Delingpole was clearly offended by the apparent comparison to devotees of quack medicine. Later, the programme featured an HIV-positive man who doesn't believe HIV causes Aids and follows a yoghurt-based treatment of his own devising, who probably didn't like being lumped in with Delingpole much.

Here’s the core of the argument from James’ critics – and it isn’t a scientific question at all. It’s a matter of semantics – a debate about what we mean by ‘consensus’. But first let’s remember one very important fact in all of this – Sir Paul Nurse is no better qualified than James Delingpole to speak with authority on climate change and the science behind AGW. Sir Paul is a very clever man – a brilliant cell biologist and geneticist who won a Nobel Prize for his work – but he has no qualification that gives him authority on the matter of climate change.

Neither is Sir Paul a philologist or lexicographer able to bring to bear a deeper understanding of what we might understand by consensus. Most importantly, he has used two very distinct applications of that word’s meaning – a general one where most scientists tend to agree with a position (the AGW application) and one where in applies to a very specific circumstance. The problem is that the manner in which we arrive at these two “consensus” positions differs greatly. The “consensus” on cancer treatment arrives from carefully tested, empirically supported research – it is not a “consensus” at all but a choice between a bone fide expert on cancer treatment and some kind of mumbo-jumbo quack medicine.

On climate change the problem is that there are plenty of scientists who have doubts about the idea of AGW. The “consensus” is one of ‘it might be so’ rather than one based on empirical understanding. And much of the “consensus” involves scientists like Sir Paul who, for all their genius, are not qualified to opine on climate change. And as for the doubters the government’s chief scientific advisor is one of them:

“I don’t think it’s healthy to dismiss proper scepticism. Science grows and improves in the light of criticism. There is a fundamental uncertainty about climate change prediction that can’t be changed.”

He said that the false claim in the IPCC’s 2007 report that the glaciers would disappear by 2035 had exposed a wider problem with the way that some evidence was presented.

“Certain unqualified statements have been unfortunate. We have a problem in communicating uncertainty. There’s definitely an issue there. If there wasn’t, there wouldn’t be the level of scepticism. All of these predictions have to be caveated by saying, ‘There’s a level of uncertainty about that’.” 

Now this is a pretty funny take on “consensus” – and begs the question as to why Sir Paul and others are so keen to target their attention to the polemicists like James Delingpole rather than towards the genuine scientific doubts about climate change and AGW. Perhaps such folk are easy targets – dismissed with a “you’re not a scientist so what would you know” approach.

For my part, I have long believed in AGW and its significance. However, without doubt, the critics are becoming more and more convincing. Which begs a question about our environmental priorities – rather than focusing on clocking how much carbon we emit would it not make more sense to concentrate on specific, identifiable issues. Looking to respond directly to habitat decline, resource depletion, energy sustainability and air pollution might be a better bet and would almost certainly be more beneficial to the planet’s population than the economic destruction envisaged in the extremes of AGW modelling.

More importantly and something we should worry about is the conclusion of some as to how science should respond to doubters:

Nurse issued a call to scientists to be more politically savvy in the wake of the so-called Climategate affair, and to make more of an effort to put data in the public domain.

Now the data bit makes sense – although we should be careful about raw data – but ‘politically savvy’? That sounds like a call for scientists to protect their position through the game of semantics – through claiming consensus where there is none, through ad hominum attacks, through the careful construction of straw men..

The very game the critics of climate science accuse those scientists of playing already. It seems to me that scientists should focus on the honest presentation of information, should welcome doubts, challenges and questions – from whatever source – and should stay far away from the lies, dissembling and spin that goes with being ‘politically savvy’.

If that was the case, we'd be far more inclined to respect scientists and to believe their science.

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