For the past nine days my inbox has been filling up with messages labelled "Your scam exposed", "The great fraud unravels" and "How do you feel now, asshole?". They are referring to a new "scientific paper", which proves that the "climate change scare" is a tale "worthier of St John the Divine than of science".

Published in two parts on consecutive Sundays, it runs to a total of 52 pages, containing graphs, tables and references. To my correspondents, to a good many journalists and to thousands of delighted bloggers, this paper clinches it: climate change is a hoax perpetrated by a leftwing conspiracy coordinated by the United Nations.

So which was the august journal that published it? Science? Nature? Geophysical Research Letters? Not quite. It was the Sunday Telegraph. In keeping with most of the articles about climate change in that publication, it is a mixture of cherry-picking, downright misrepresentation and pseudo-scientific gibberish. But it has the virtue of being incomprehensible to anyone who is not an atmospheric physicist.

The author of this "research article" is Christopher Monckton, otherwise known as Viscount Monckton of Brenchley. He has a degree in classics and a diploma in journalism and, as far as I can tell, no further qualifications. But he is confident enough to maintain that - by contrast to all those charlatans and amateurs who wrote the reports produced by the UN's Intergovernmental Panel on Climate Change - he is publishing "the truth".

The warming effects of carbon dioxide, Lord Monckton claims, have been exaggerated, distorted and made up altogether. One example of the outrageous fraud the UN body has committed is the elimination from its temperature graphs of the "medieval warm period", which, he claims, was "real, global and up to 3C warmer than now". He runs two graphs side by side, one of which shows the temperature record over the past 1,000 years as rendered by the UN panel, and the other purporting to show real temperatures over the same period.

The world was so hot 600 years ago, he maintains, that "there was little ice at the North Pole: a Chinese naval squadron sailed right round the Arctic in 1421 and found none". By contrast the planet is currently much cooler than climate scientists predicted. In 1988, for example, the world's most celebrated climatologist, James Hansen of Nasa, "told the US Congress that temperature would rise 0.3C by the end of the century (it rose 0.1C), and that sea level would rise several feet (no, one inch)".

Most importantly, "the UN repealed a fundamental physical law", doubling the size of the constant (lambda) in the Stefan-Boltzmann equation. By assigning the wrong value to lambda, the UN's panel has exaggerated the sensitivity of the climate to extra carbon dioxide. Monckton's analysis looks impressive. It is nonsense from start to finish.

His claims about the Stefan-Boltzmann equation have been addressed by someone who does know what he's talking about, Dr Gavin Schmidt of Nasa's Goddard Institute for Space Studies. He begins by pointing out that Stefan-Boltzmann is a description of radiation from a "black body" - an idealised planet that absorbs all the electromagnetic radiation that reaches it. The Earth is not a black body. It reflects some of the radiation it receives back into space.

Schmidt points out that Monckton also forgets, in making his calculations, that "climate sensitivity is an equilibrium concept": in other words that there is a time-lag of several decades between the release of carbon dioxide and the eventual temperature rise it causes. If you don't take this into account, the climate's sensitivity to carbon dioxide looks much smaller. This is about as fundamental a mistake as you can make in climate science.

What of his other claims? Well, the reason the "medieval warm period" doesn't show up on the UN panel's graphs is simple. As far as climatologists can tell, there wasn't one. So why did the Vikings, as Monckton points out, settle in Greenland?

As a paper published in Reviews of Geophysics shows, Vikings first arrived in Greenland at the very beginning of the "warm period" Monckton discusses, when temperatures, even according to his graph, were lower than they are today. They did so because life had become too hot for them in their adopted home (Iceland): not climatically, but politically. There does appear to have been a slight warming in some parts of the northern hemisphere. There is no reliable evidence that this was a global phenomenon. As for the Chinese naval squadron sailing round the Arctic, it is pure bunkum - a myth long discredited by serious historians.

So what of those graphs? Look at them carefully and you see that they are measuring two different things: global temperatures (the UN panel's progression) and European temperatures (Monckton's line). You will also discover that the scales are different.

As for James Hansen, he did not tell the US Congress that temperatures would rise by 0.3C by the end of the past century. He presented three possible scenarios to the US Senate - high, medium and low. Both the high and low scenarios, he explained, were unlikely to materialise. The middle one was "the most plausible".

As it happens, the middle scenario was almost exactly right. He did not claim, under any scenario, that sea levels would rise by several feet by 2000. But a climatologist called Patrick Michaels took the graph from Hansen's paper, erased the medium and low scenarios and - in testimony to Congress - presented the high curve as Hansen's prediction for climate change. A memo sent in July from the Intermountain Rural Electric Association, a US company whose power is largely supplied by coal, revealed that Michaels has long been funded by electricity companies. "In February this year, IREA alone contributed $100,000 to Dr Michaels." Michaels, it says, meets periodically with industry representatives to discuss their activities in countering stories about climate change.

Pat Michaels's misrepresentation of Hansen's claims was picked up by Michael Crichton in his novel State of Fear, and somehow transmuted into an "error" of 300%. Monckton gives no source for his claim about Hansen, but Crichton's novel features in his references. The howlers go on and on. There is scarcely a line in Lord Monckton's paper which is not wildly wrong.

Yet none of this appears to embarrass the Sunday Telegraph, which championed his findings this week in a leading article. I think I know what the problem is. At a meeting of 150 senior journalists last year, who had gathered to discuss climate change, the chairman asked how many people in the audience had a science degree. Three of us raised our hands. Readers cannot expect a newspaper editor to possess a detailed understanding of atmospheric physics, but there should at least be someone who knows what science looks like whom the editor consults before running a piece.

A scientific paper is one published in a peer-reviewed scientific journal. This means it has been subject to scrutiny by other experts in the field. This doesn't suggest that it's the last word on the subject, but it does mean it is worth discussing. For newspapers such as the Sunday Telegraph the test seems to be much simpler. If they don't understand it, it must be science.

Monbiot.com