Hardcore sceptics land no punches on hard core science

Published in Tribune, 12 February 2010

If you weren’t paying too much attention, the past few months might have convinced you that the sceptics are right and global warming is a myth. If so, congratulations – you have joined the illustrious company of Nigel Lawson, Jeremy Clarkson and Sarah Palin.

More worryingly, you have also joined an increasingly large minority of the British public that doubts the science – a group which, if we are to believe ConservativeHome’s Tim Montgomerie, now includes most Tory MPs.

All of which is rather unfortunate, given that the deniers haven’t actually won the argument over anything of substance. What they have done rather more successfully is to frame the debate in a way which makes them look more reasonable than they are and which makes the scientists look less reliable than they are.

In the 1980s, anti-tax campaigners in the United States managed to redefine talk about inheritance tax so that the levy became known as “death tax”. In the 1990s, Labour succeeded in changing the language of debate on the public finances so that spending became “investment”. Today, the Conservatives are trying to create a narrative of a “broken Britain” out of individual cases of youth crime.

There’s nothing rare or even particularly sinister about this and it’s a standard debating technique. But it can create the impression that an argument has been won before any evidence is even aired. In the case of political campaigns, it’s part of the arsenal of techniques used to persuade people and, infuriating as it might sometimes be, it’s not going to go away.

In the case of climate science, it’s a bigger deal, as the discourse is being manipulated to imply that there is serious doubt about climate change – which there is not. The result is not just to undermine climate science and to fool intelligent people into supporting the sceptics: it also undermines public understanding of science more broadly. Whether through ignorance or malice, the sceptics are dishonest to the core, yet they have managed to redefine the terms of the debate to make their dishonesty mainstream.

Global warming, it hardly seems necessary to say, is not like inheritance tax. Its existence cannot be legislated in or out of existence because we happen to like or dislike the idea. What is being framed here is not a debate between supporting or opposing a political proposal, but a debate between accepting or denying the broadly accepted scientific consensus.

Deniers like to throw about claims of scientific incompetence, of dogmatism and of corruption each time they uncover the slightest flaw in the research. “Don’t listen to those charlatans”, they say, “they might claim to be good scientists, but they’re not.” In fact, it is the sceptics who completely misunderstand the nature of science

Over the years, identifying exactly what makes science tick has been a big question for the small band of people who are interested in the philosophy of science. (Yes, we do exist.) And while no one has ever quite managed to pin it down in all its complexity, the Hungarian-born philosopher Imre Lakatos came up with one of the more persuasive models of how science works.

In his view, a research programme in any given field has a “hard core” of basic theories and a diffuse set of secondary theories and supporting evidence which he called the “protective belt”. Science, he argued, progresses mainly by dealing with problems raised with the supporting material, which is discarded or modified along the way as necessary. But unless something quite radical is discovered, you do not tear everything up and start again: the hard core remains as the protective belt takes a beating and, in time, usually recovers, with new theories and better data to replace the duds.

The bread and butter of science is therefore to test, refine and modify our knowledge of supporting theories. Revolutionary geniuses such as Einstein or Newton are not typical of how science works – the overwhelmingly vast majority of research is to refine old theories, not to question our fundamental assumptions.

So what would Lakatos say about climate change? I am pretty sure he would see the sceptics for what they are: a ragtag army of conspiracy theorists, right-wing extremists, corporate patsies and Ayn Rand worshippers. More importantly, he would see that the few punches they have landed are no reason to question a scientific consensus which remains fundamentally sound: the hardcore deniers haven’t laid a finger on the hard core of science, no matter what they claim.

In other words, publicly chipping away at the edges of climate science as the sceptics are doing might help change the public narrative in their favour, but it does nothing at all to change the science. That, not “bad science”, not blinkered dogmatism and not corruption is why the avalanche of fury that has been unleashed since the University of East Anglia email server was hacked has not moved mainstream scientific opinion one jot.

Suggesting otherwise is not just a grave misunderstanding of the theories and data of climatology – but a misrepresentation of how science actually works.

A hindsight test for hacks

Published in Tribune, 29 January 2010

Since actually knowing anything about how science works doesn’t seem to be a requirement for pontificating about it in the media, I’m going to play at being an ophthalmologist. The patient is the press and the diagnosis is excellent: it has perfect 20/20 hindsight.

What’s more, there is no need to visit those money-grubbing opticians with their sinister conspiracy to force annual eye tests on us all. Perfect hindsight can be diagnosed at home: it is the inevitable consequence among lazy journalists when scientists are found to have had anything other than 20/20 foresight.

Since it’s now clear that the swine flu pandemic wasn’t a global catastrophe, certain portions of the commentariat are turning on the scientists whose words they hyped less than a year ago, and are now claiming that the whole thing was a scam.

Most people are happy that swine flu hasn’t killed us all. Some journalists, however, appear to see it as a good thing because it makes for an easy article to bash out in a few minutes before going down to the pub.

Make a few accusations of conflicts of interest, insinuate that the scientists knew all along that the pandemic was not going to be a big deal, but nevertheless claimed the contrary, drop in a few mentions of “experts” in scare-quotes and you have the beginnings of a good rant.

Of course, because you don’t really know anything about science and you have 1,200 words to write by lunchtime you’ll have to pad the whole thing out with irrelevant details – so sprinkle about a few mentions of times when expert predictions were too alarmist, like mad cow disease and the millennium bug, while conveniently avoiding cases where they were right, such as AIDS, asbestos and tobacco. Then say that spiv-like Western governments are now trying to flog off their surplus vaccine stocks to the third world. And voila, you have a column, and a good excuse to pop down to the King and Keys for a pint or three of lunch.

That swine flu was hyped up is not really in question – and that much was obvious right from the start (as I pointed out in these very pages on March 9 last year). But the real misunderstanding was not in the risk caused by swine flu, which was correctly and widely stated as being uncertain (but probably relatively low).

Rather, the problem was the widespread and infuriating assumption that scientific claims are definite rather than provisional, combined with a sensationalist tendency to quote the most dramatic projected death tolls rather than the most realistic. Experts may have more facts at their disposal and more training than members of the public, but that does not make them infallible. Scientists deal in predictions – educated guesses – not prophecy. We hear far too much talk of scientific “facts” and not nearly enough about scientific “hypotheses” – something for which scientists are partly to blame, but which the media should be far more responsible in reporting than it is.

So the suggestion that the overreaction to swine flu was to do with conspiracy and fear deliberately whipped up by scientists seems odd, partly because most of the scaremongering was from the media rather than the experts or the Government, and partly because official responses to the outbreak in this country were mostly quite sensible given what was known at the time.
But let’s run with it for a moment. What evidence is there that there was a conspiracy?

There was clearly some excessive language used and there is without doubt an unhappily cosy relationship between parts of the pharmaceutical industry and some leading scientists. But neither of those prove widespread malpractice.

Another way to look at it might be to carry out a thought-experiment: what would have happened during the swine flu outbreak if there were no conspiracy? We can then compare that with what actually happened and maybe draw some conclusions.

My guess is that if there had been no conspiracy, there would have been a good deal of initial confusion and uncertainty as unreliable reports of the disease came out. Then, as the virus spread and our knowledge of it firmed up, contingency plans for bird flu (remember that?) would be put into action. Common sense public health efforts to prevent transmission and contingency plans to mitigate the effect on the economy would have been put into place. Meanwhile, governments would have chivvied pharmaceutical companies to develop and bring to market a vaccine as quickly as possible. That would have been a responsible and sensible approach to follow.

Once the worst had passed, infection rates had fallen and it became clear the disease was not as serious as feared, you might expect Western governments to try to sell their vaccine stocks on to countries where swine flu was still widespread – perhaps in poorer regions with less developed health systems, such as North Africa, south-east Europe and parts of Asia.

Finally, if it became clear that the pandemic had been a bit of a damp squib and that not that many people died, we might expect contrarian newspaper columnists to start claiming that the whole thing was a scam and a conspiracy, and that we should never trust so-called experts ever again.

The eagle-eyed among you may notice that that is exactly what happened.

No Christmas cheer for climate science

Published in Tribune, 18 December 2009

It hasn’t been a very good few weeks for climate science. The Copenhagen summit trundles onwards to certain fudge or failure. A recent Times poll appears to show fewer than half of all Britons even believing that global warming exists, and the storm rages on over the leaked emails from the University of East Anglia’s Climate Research Unit.

The United Nations climate summit is due to conclude after this issue of Tribune goes to press – but, regardless of the eventual outcome, the fact that all the countries have agreed at least in principle to deep cuts in emissions is a start.

The Times poll, too, isn’t quite the disaster it first seems – though the reporting of it raises some serious questions about journalistic integrity. As the excellent new website Climatesock.com points out, the raw data from the pollsters shows that the low figure of 41 per cent of people in Britain who believe in climate change, cited with the most prominence in the Times article, was reached only by excluding a further 32 per cent who agreed with the statement “there is a widespread theory that climate change is largely man-made, but this has not yet been conclusively proved”.

Not quite what it seems, then – and to think it’s the climate change deniers who accuse the climate scientists of cherrypicking data and coming up with bogus conclusions.

Indecisiveness by politicians is hardly news, nor is sensationalism from a Rupert Murdoch-owned newspaper. But the accusations of dishonesty against the researchers at the University of East Anglia are a far bigger story, since they erode the credibility of a previously unimpeachable source.

Yet while the leaked emails aren’t exactly edifying – and they certainly don’t reflect well on the individuals involved – the suggestion that they undermine the whole edifice of climate science is nonsense. The real damage here is in the awful PR, rather than the relatively minor malpractice revealed.

Part of the trouble here isn’t just that the scientists misbehaved. It’s that we have come to hold them to a higher standard than we do everyone else.

Science generally works better when people are honest and open, but if we expect a level of integrity that is unobtainable then we simply set science up for a fall. Researchers are human beings, with all that entails: don’t believe the fairy stories that science is collaborative and free. It is intensely competitive, both for glory and for money – two things that tend to bring out the worst in humans.

Unfortunate or not, it’s the way it is, and while it should inform our judgement of scientific discoveries (some degree of scepticism is always in order, particularly for the preliminary results that so often form the basis of news stories), it shouldn’t throw into doubt the entire edifice of scientific knowledge. Peer review, however imperfect, exists to protect data from being compromised by individuals, an implicit recognition that scientists aren’t perfect.

And why would they be? It’s a matter of historical record that this sort of thing, and worse, has always gone on.

Do we think any less of Isaac Newton’s theories because of his relentless bullying of the astronomer John Flamsteed? Newton went as far as publishing an early draft of a book by Flamsteed without permission or even attribution, leaving the astronomer to go around buying and destroying the offending tomes. Newton may well have been a complete turd, but I don’t hear gravity sceptics claiming his laws of motion are bogus as a result.

Francis Crick and James Watson discovered the structure of DNA and won a Nobel Prize in part based on data discovered by a rival team of researchers at another university – whom they then denigrated in the paper revealing their results. Watson went on to offend women, gays, blacks and fat people in a series of outbursts that would make the Duke of Edinburgh proud. Is Watson a bastard? Unquestionably. But again, where are the DNA sceptics, insisting that all of genetics is undermined as a result?

Of course, the difference is that there isn’t a multi-billion dollar global industry whose profits rely on fooling people into believing gravity and DNA are hoaxes. Maybe that’s the real scandal.

How a tabloid sledgehammer smashed Professor Nutt

Published in Tribune, 20 November 2009

It’s three weeks now since the Home Secretary chewed up and spat out David Nutt, erstwhile chair of the Advisory Council on the Misuse of Drugs. The man was guilty of that most post-modern of offences, being too honest in a system which puts a premium on hypocrisy.

Nutt worked as a scientific adviser within an international framework of drugs control institutions which has no time for scientific advice, and which puts the political expediency of a 1961 treaty above any other issues that might conceivably be relevant. And as cheerleaders for this absurd system, he had to put up with The Sun and the Daily Mail.

Against the triple whammy of international law, tabloid journalists and a coward of a home secretary, the poor man never stood a chance.

The British Government does not control its own drugs policy. The Misuse of Drugs Act of 1971, the main piece of legislation on the subject, is virtually identical to equivalent laws in almost every country in the world. This is because drugs policy is internationalised like no other issue.

The Single Convention on Narcotic Drugs is the main treaty governing drugs policy around the world. It explicitly bans the “cultivation, production, manufacture, extraction, preparation, possession, offering, offering for sale, distribution, purchase, sale, delivery on any terms whatsoever, brokerage, dispatch, dispatch in transit, transport, importation and exportation” of numerous drugs (including cannabis) worldwide.

It recommends sanctions against any country that does not.

It also sets out the broad outline of the scheme which in this country puts drugs into class A, B or C.

This – not health, not public opinion, not science – is the real reason why cannabis will never be decriminalised. The treaty is virtually impossible to repeal. With over 180 countries in the world, almost all of them signed up, the legalisation of any of these drugs would require the simultaneous support of about four-fifths of the world’s nations to become a reality. And any country which acted unilaterally without the support of the vast majority of signatories would end up on the wrong end of sanctions.

The elements of drug policy left to the nation state in this system are insignificant in comparison.

The extent to which individuals are criminalised for possession is one area in which governments have nominal control (hence the Netherlands turning a blind eye to cannabis use), as are the penalties drug users and dealers face when caught (hence

Britain’s choice of how, but not whether, to classify cannabis). But the role of national governments in this field is pretty much limited to the enforcement of rigid international regulations.

Given this, Britain’s Advisory Council on the Misuse of Drugs was never a particularly serious organisation. With an inflexible framework based on rigid and virtually inalterable treaties rather than national laws, the ACMD is not in a position to have any real input into how drugs are treated. Such a position is even built into the ACMD’s title – the assumption that use equals misuse.

But at least it used to inject a little sanity into the application of an insane law.

The ACMD’s role, when it worked properly, was positive, if limited. It was on its recommendation that David Blunkett downgraded cannabis to class C in 2004 – about as close to legalisation that was possible under Britain’s treaty obligations, and a rare moment of relative sanity on the matter.

But since then, the moral panic over drugs has heated up again. One of Gordon Brown’s first acts as Prime Minister was to pacify the media by reclassifying cannabis up again to class B – against the scientific advice of the ACMD – and to refuse the downgrading of ecstasy from class A to class B – again, against scientific advice.

This means that possession of ecstasy in Britain is punishable by up to seven years in prison; cannabis by five.

This is the moral panic David Nutt stood in the way of. When things reach such a fever-pitch of irrationality that it seems normal, even desirable, to lock up otherwise law abiding citizens for up to seven years for doing something which affects no one but themselves, it should hardly surprise us that the tabloids went berserk at a scientist who was just doing his job properly.

And not satisfied with having ousted the professor, The Sun and Daily Mail have now set about attacking his reputation and that of his family. Lowlife reporters from those newspapers have been trawling his children’s Facebook pages in order to find dirt to smear the family with in print.

In a democracy, we have the government and the newspapers we deserve. We also have the scientific advice we deserve.

And if there is one thing this whole story teaches us, it’s that we didn’t deserve David Nutt – a good man traduced for no good reason. Now we’re going to have to make do without him.

Energy: there's no accounting for waste

Published in Tribune, 22 October 2009

Is the government so determined to push through nuclear power stations that it is planning secret subsidies to the industry which will add 10% to household electricity bills? That's the conclusion of the Guardian, which ran a long news article and a highly critical editorial on the subject this Monday.

The truth is a little murkier. The story, while factually accurate, misrepresented the proposal rather badly. Nuclear power understandably triggers weary scepticism in many otherwise apathetic people - the history of the industry is closely bound with international realpolitik, intrigue at home and the warm afterglow of over two thousand nuclear bomb test detonations since 1945.

But, in fact, this new policy is a lot better than what we've got used to, and the Guardian called this one wrong. What at first seems like a subsidy for an unpopular type of power turns out, on closer inspection, to be something rather different: a cut in the implicit subsidy for fossil fuels. While there is legitimate debate about whether the risks of nuclear power outweigh its benefits, fossil fuels unquestionably cause massive environmental damage and human misery.

The government proposal, if implemented, is not to channel money to nuclear power, but to raise the cost of CO2 emissions licenses, which are currently unrealistically cheap. Recession notwithstanding, this is a very good idea.

Every type of energy source has its costs, whether they be for fuel, labour or construction. While explicit subsidies in the UK are currently directed towards renewables (particularly wind turbines) there are actually plenty of other ways in which the price we pay on our electricity bills does not reflect the true cost of generation.

In particular, for fossil fuels there is a glaring mismatch between the full economic cost of resource extraction (digging the coal out of the ground, or pumping the oil or gas), which we do pay up front, and the economic cost of the pollution produced, which we don't.

This is not abstract, nor is it the wishy-washy moral argument of a hand-wringing liberal, nor is it even an argument about saving a pure and pristine environment from smoke and soot.

The cost of pollution is paid for one way or another whatever we do - it's just that we don't recognise this through our energy bills at present. But battered coastal defences, stretched NHS budgets for respiratory diseases, countless deaths of miners (much of our coal is now imported from dangerous mines abroad) and droughts which decimate third-world farming are all external costs of burning coal.

The only question is whether we take these costs fully into account when planning our energy policy. At present we don't - which, as well as harming the environment, will probably end up costing more. The cheapness of fossil fuels is a mirage, a market failure brought about by a system which recognises some costs, but ignores or discounts others.

Seen in this light, a rise in energy bills, with its attendant increase in costs for the poor, seems less unethical - particularly since the brunt of the invisible subsidy to coal generation is at present borne by the disadvantaged anyway. The rich can always pay their way out of a crisis - the poor can't.

Besides, raising the cost of fossil fuels isn't actually about increasing the total spent on power - since the money will have to be spent anyway mitigating coal's environmental and health impacts, this would be little more than a change in accounting practices. That's not to say it is merely a matter of bureaucracy - the way businesses and governments account for profits and costs has a huge impact on what decisions they make. Just ask Northern Rock - an organisation that realised far too late that its apparently profitable business was completely unsustainable.

So the Guardian isn't really correct in saying that this is a bung to the nuclear industry - it's more of a slap for coal. The trouble is, the nuclear industry gets plenty of other hidden subsidies - and this is where I concede that the newspaper does have a point of sorts. If the argument for recognising the full cost involved in coal power is unanswerable, then a similar case can and should be made for nuclear.

The cost of decommissioning old nuclear power plants, for example, still isn't fully accounted for, though even the provisional figures are breathtaking. The Dounreay site on the northern coast of Scotland, for example, is currently being demolished and decontaminated - a process which is projected to take until 2336 -and that's not a typo. (The interim price for the first 30 years of this is close to £2.9bn.)

The cost of potentially disastrous (if vanishingly unlikely) nuclear accidents is not factored in either. And we still don't know what to do with the waste: as I never tire of saying, in six decades of nuclear power generation, humanity has not managed to permanently dispose of any of the high-level waste produced by nuclear power plants in that time. This isn't just a source of concern on safety grounds - it also leaves us in the dark as to the future costs of dealing with the waste.

So the Guardian is both wrong and right. It is wrong that the proposals are a bad idea, and wrong that they are simply a subsidy to nuclear power. But they are right that nuclear power gets far too many hidden bungs. These need to be eliminated just as much as those to coal.

All this talk of economic costs, of raising prices and of level playing fields in a free market might all sound a little Thatcherite for an article in Tribune. But regardless of what political decisions we make about the organisation of the energy industry, whether we want it wholly privately run, wholly public, or somewhere in between, the argument remains the same.

Decisions about our future energy needs really ought to be based on a full assessment of the economic and environmental costs involved - and any subsidies we decide to pay, whether to wind turbines or nuclear reactors, need to be explicit, evidence-based and properly accounted for.

Norman Borlaug: an expert in his field

Published in Tribune, 25 September 2009

The ranks of Nobel peace laureates are packed with politicians and campaigners. On the few occasions when scientists have entered the ranks, it is usually nothing to do with their research: Arctic explorer and researcher Fridtjof Nansen (1922) got it for inventing refugee travel documents; Chemist Linus Pauling (1962) and physicist Joseph Rotblat (1995) both won for their campaigning work against nuclear weapons.

Among this distinguished company, the biologist Norman Borlaug, who died earlier this month, stands out as an exception – or so it seems – because when he won the peace prize in 1970, it was for the work he did as a scientist rather than any political action he took part in on the side. It’s hardly surprising there aren’t more like him – after all, the Nobel Peace Prize is a political one above all else.

Borlaug’s work on developing new varieties of wheat was directly responsible for the “green revolution” which massively increased food production across the world. Arguably, it did more to prevent starvation than any humanitarian effort in history, even if the environmental impacts have been mixed.

The extent and speed of change brought about by the green revolution dwarfs anything we can comprehend in the west. The agricultural and industrial revolutions of 18th century England – perhaps the closest equivalent in our history – did not take place within living memory and, in any case, happened over a period of decades. Borlaug’s wheat and the introduction of chemical fertilisers transformed the economic and social outlook of the third world in just a few years. The increase in food production was so rapid and so unexpected that India and Pakistan ran out of sacks to carry the wheat, railway carriages to transport it and warehouses to store it.

Borlaug began working on crops in Mexico in 1944, initially developing disease resistant crops, before moving onto the problem of breeding more productive varieties of grain.

He realised that crossing wheat varieties to increase the amount of grain they produced would eventually hit a natural barrier – the ability of the stalk to carry the weight of the grains on the tip. High-yield varieties of the time, when combined with powerful fertilisers, had a tendency to fall over and die because they were so top-heavy.

His elegant solution to the problem was to create varieties of wheat with shorter and stiffer stems, which were better able to support their own weight.

Wheat fields, as a result, look quite different from those of a century ago – Borlaug’s dwarf wheat and its successors, which overwhelmingly dominate worldwide agriculture, are little more than half the height of the crops we used to grow.

Once the crops themselves were developed, Borlaug threw himself into promoting them, most notably by travelling to India and Pakistan during their 1965 war, distributing and planting the grain on both sides of the front lines.

Alongside the new varieties, mechanisation of agriculture and new artificial fertilisers transformed third world subsistence agriculture into a mass producer of food and, unimaginable a few years earlier, cash crops too: by 1974, less than a decade after Borlaug’s visit, India was self-sufficient in grain.

This achievement has been widely discussed and some have argued that the green revolution saved as many as a billion people from starvation. It’s always hard to know what to make of what-if scenarios such as this one – and biographies and obituaries of Borlaug have, for obvious reasons, tended towards hagiography. But what is beyond question is that in Mexico, India and Pakistan, the decade following the introduction of high-yield dwarf wheat saw production nearly double. Famine, once common on the Subcontinent, has not returned since.

The green revolution transformed agriculture in negative ways, too – monoculture, the loss of genetic diversity, over-exploitation of water resources, heavy reliance on mechanisation and a thirst for synthetic chemicals that would make the Soil Association break into sweat. But Borlaug, to his credit, never denied this, simply pointing out that the criticism of poor countries trying to feed themselves tended to come from the rich and well-fed.

He defended his work on environmental grounds as well. Intensive agriculture and genetic modification, Borlaug argued, are actually good for the environment. They allow more food to be produced on less land saving forests from being chopped down and habitats from being destroyed – a point which deserves more exposure than it gets in discussions over the merits of organic farming.

If there’s one other thing Borlaug’s life and work should teach us, it is that his Nobel win was perhaps not quite as unusual as it might seem. Yes, unlike Nansen, Pauling and Rotblat, he won the award because of the work he did in his job as a scientist. But the motivations, objectives and results of Borlaug’s work were nothing if they were not political.

Putting the spin into global warming

Published in Tribune, 31 July 2009

Last Sunday, the Observer published a series of photographs showing a dramatic reduction in summer ice coverage in the sea north of Alaska. The photos were billed as the “secret evidence of global warming [which] Bush tried to hide.”

The article is damning. Photos taken by American military satellites during George W Bush’s presidency, the newspaper explains, were classified by the White House because they exposed the dishonesty of the administration’s line that climate change was unproven. The suppression of the photos fits in to a consistent pattern of spin and disinformation during the former President’s tenure that reveals a complete disregard for scientific evidence.

Mercifully, Barack Obama’s record so far is a great improvement. But in more than one way, the release of the photos has shown echoes of the administration that kept them secret. Just as their suppression was politicised, so was their release; and just as the media has grossly exaggerated arguments against climate change, the coverage of the affair in the Observer and elsewhere has hardly been exemplary.

The timing of the photos’ release is particularly curious. Yes, they were requested by the National Academy of Sciences, which is nobody’s stooge. But when, at the best of times, such requests are usually processed in months, that the publication of the photos followed within hours is certainly worthy of note. The timestamps on the files show they were ready for release months ago. Why now?

It is surely no coincidence that the release of the photos came just as Obama’s flagship American Clean Energy and Security Act was running into trouble. After passing the House of Representatives with only a razor-thin margin of 219-212 in June, the bill is now at risk of being defeated in the Senate despite the sizable Democratic majority there. The proposed law would introduce a European Union-style emissions trading system in the United States, where companies have to buy licenses to pollute – something deeply unpopular with Republicans but also a large minority of the President’s own party.

So what could be better for Obama than to shore up support within the Democrats, polarise the argument and isolate the Republicans by revealing the malfeasance of their former President – while at the same time doing some good for US science? Machiavelli would be proud.

And what of the media? The Observer presented the photos as “demonstrat[ing] starkly how global warming is changing the Arctic”.

But the photos don’t (quite) do that. They do plenty of things which are interesting to climate scientists, not least by letting them measure the extent and number of pools of melt-water that form on the surface of the ice. They also give interesting snapshots of sea ice and glaciers throughout the Arctic region.

But one thing they don’t show is incontrovertible evidence of receding sea ice.

The most dramatic looking of the photos, the ones chosen by the Observer (and other news organisations) to illustrate the story, and which appear on the cover of this week’s Tribune, show two views of the settlement of Barrow on the northern coast of Alaska. In the first, the sea is covered with a thick sheet of ice, leaving only a narrow, iceberg-strewn channel along the coast. In the second photo, the ice has completely vanished.

It looks impressive, but the suggestion that anything at all can be extrapolated from any two years of ice cover, let alone two consecutive years as these photos show, should raise laughs from anyone who knows anything about climate science. No one claims global warming is that rapid, and in any case, changes in the climate are measured in long trends over decades, not in the more or less random fluctuations from one year to the next. Some years are warm, some years are cold – and that has nothing to do with climate change.

In fairness, the misrepresentation here was not by the US Government – the released documents note that “observations of sea ice position reveal considerable year-to-year variability” and that the Barrow photos offer “information on smaller-scale properties of ice” rather than any global insight into the changing climate.

And besides, these new photos are an addition to an already overwhelming body of evidence which supports the alarming conclusions of climate scientists – they do not need to be taken on their own.

Nonetheless, it’s a bit worrying when those defending science feel the need to over-egg the pudding. Nobody should ever have to exaggerate evidence for climate change. There is no need to as the evidence is strong enough to stand on its own. But equally importantly, hyperbole is hugely counterproductive. Those who insist there is a conspiracy and that global warming is a hoax get a lot of airtime (including a recent front cover of The Spectator so bizarre it has to be seen to be believed), and they love picking little holes in their opponents’ arguments. So why make things easy for them?

The sceptics’ arguments are flimsy, but that’s no reason to try to emulate them. To put it bluntly, so what if climate scientists and their supporters are held to a higher standard of evidence and ethics than the coalition of crooks and nutters who choose to deny global warming? We’re right and they are wrong and we have nothing to fear from the truth.