Flere har latt seg fascinere av Channel 4s program The Great Global Warming Swindle. Noen tror at det at et synspunkt ikke får gjennsomslag betyr at det blir undertrykket. Men dette er en feilslutning.

Det er riktig at noen av tidenes største vitenskapsmenn var miskjent i sin samtid. Men derfra til å slutte at alle outsidere er sannhetens profeter er noe helt annet. Men det er en slik kjetter-forherligelse klimaskeptikerne soler seg i. Det samme gjør for øvrig 911-konspiratørene: det ligge noe bak.

George Monbiot har gått programmet etter i sømmene og tilbakeviser påstandene punkt for punkt. Hvis noen seriøst hadde greid å så begrunnet tvil om klimatrusselen, ville nyheten gått verden rundt på noen dager (det tar noe tid å sjekke fakta). Men det tar også tid og krefter å tilbakevise vrøvl: Monbiot har tatt seg bryet med å sjekkeThe Great Global Warming Swindle og punkterer programmet.

Were it not for dissent, science, like politics, would have stayed in the dark ages. All the great heroes of the discipline – Galileo, Newton, Darwin, Einstein – took tremendous risks in confronting mainstream opinion. Today’s crank has often proved to be tomorrow’s visionary.

But the syllogism does not apply. Being a crank does not automatically make you a visionary. There is little prospect, for example, that Dr Mantombazana Tshabalala-Msimang, the South African health minister who has claimed Aids can be treated with garlic, lemon and beetroot, will be hailed as a genius. But the point is often confused. Professor David Bellamy, for example, while making the incorrect claim that wind farms do not have «any measurable effect» on total emissions of carbon dioxide, has compared himself to Galileo.

The problem with The Great Global Warming Swindle, which caused a sensation when it was broadcast on Channel 4 last week, is that to make its case it relies not on future visionaries, but on people whose findings have already been proved wrong. The implications could not be graver. Just as the government launches its climate change bill and Gordon Brown and David Cameron start jostling to establish their green credentials, thousands have been misled into believing there is no problem to address.

The film’s main contention is that the current increase in global temperatures is caused not by rising greenhouse gases, but by changes in the activity of the sun. It is built around the discovery in 1991 by the Danish atmospheric physicist Dr Eigil Friis-Christensen that recent temperature variations on Earth are in «strikingly good agreement» with the length of the cycle of sunspots.

Påstandene plukkes fra hverandre en etter en, men det skjer i fagblader som Science, over tid, og folk flest må stole på hva andre sier. Da er det lett å falle for de billige poengene og underslå innvendinger fra fagfolk. Monbiot anklager Channel 4 for å gå etter kontrovers og strid. Det skaper oppmerksomhet og salg. Sannhetsgehalten bryr de seg mindre om. Den overlater de til andre.

Until recently, when found to be wrong, scientists went back to their labs to start again. Now, emboldened by the denial industry, some of them, like the film-makers, shriek «censorship!». This is the best example of manufactured victimhood I have come across. If you demonstrate someone is wrong, you are now deemed to be silencing him.

But there is one scientist in the film whose work has not been debunked: the oceanographer Carl Wunsch. He appears to support the idea that increasing carbon dioxide is not responsible for rising global temperatures. Wunsch says he was «completely misrepresented» by the programme, and «totally misled» by the people who made it.

This is a familiar story to those who have followed the career of the director Martin Durkin. In 1998, the Independent Television Commission found that, when making a similar series, he had «misled» his interviewees about «the content and purpose of the programmes». Their views had been «distorted through selective editing». Channel 4 had to make a prime-time apology.

Cherry-pick your results, choose work which is already discredited, and anything and everything becomes true. The twin towers were brought down by controlled explosions; MMR injections cause autism; homeopathy works; black people are less intelligent than white people; species came about through intelligent design. You can find lines of evidence which appear to support all these contentions, and, in most cases, professors who will speak up in their favour. But this does not mean that any of them are correct. You can sustain a belief in these propositions only by ignoring the overwhelming body of contradictory data. To form a balanced, scientific view, you have to consider all the evidence, on both sides of the question.

But for the film’s commissioners, all that counts is the sensation. Channel 4 has always had a problem with science. No one in its science unit appears to understand the difference between a peer-reviewed paper and a clipping from the Daily Mail. It keeps commissioning people whose claims have been discredited – such as Durkin. But its failure to understand the scientific process just makes the job of whipping up a storm that much easier. The less true a programme is, the greater the controversy.

Don’t let truth stand in the way of a red-hot debunking of climate change

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