Here’s a video that you absolutely must see.

Not, I hasten to warn you, because it’s exciting, well-produced or informative; rather, because of the fascinating light it sheds on the debate about global warming in general and also, in particular, on the ongoing controversy about whether organisations like NASA and NOAA are playing fast and loose with the world’s temperature data sets.

According to the video’s creator and star, Dr Kevin Cowtan, the latter suggestion is a nonsense. Using charts of South American and global temperatures, he painstakingly refutes suggestions by Christopher Booker and also (though tragically I don’t get a mention) by me that there is anything suspect, let alone corrupt or fraudulent, in the adjustments that NASA and NOAA have been making to the raw temperature data from weather stations around the world.

If you stumbled on it by accident on YouTube I think you’d be quite persuaded. Cowtan’s tone is soft and reasonable; the science, as he presents it, seems to stack up: a) there are perfectly valid reasons for these adjustments, to do with homogenising the raw data when it looks out of kilter with neighbouring but possibly more accurate weather stations, and with the changing nature of measuring equipment and b) the adjustments are, in any case, minor – altering the raw data by no more than 3 per cent.

When you Google “Dr Kevin Cowtan” he appears reassuringly neutral in this affair. He works in the Department of Chemistry at the University of York, his current speciality being X-ray crystallography. A proper scientist, then, with no dog in this fight. Or so it looks until you scroll down a bit and see that his other area of research is “climate science.”

My climate science research focuses primarily on problems which are relevant to the public understanding of climate science. With my colleague Robert Way I have been investigating biases in historical temperature record from weather stations. Our primary work concerns temperature change over the past two decades. The main temperature record providers show a slowdown in the rate of warming over this period, however when biases in the temperature record are taken into account, we find that part of the slowdown disappears. I am also involved in climate science communication, and am contributing to a massive online course run by the University of Queensland. I can offer undergraduate projects in this area for students who are interested to develop science communication skills.

So, not a neutral party after all then, but someone who depends for part of his livelihood on the lavish funding available in academe for those who promote the climate “consensus.” Perhaps, in the interests of full disclosure, he might have mentioned this detail on his YouTube biography. But I mean that only as a very mild and largely inconsequential criticism. What matters is not what Cowtan does for a living (“the motive fallacy”) but whether or not he has got his facts right.

And according to this counterblast from Dave Burton – a US computer programmer, sea level specialist and IPCC expert reviewer on AR5 – he hasn’t.

Burton’s key point is this: where Cowtan claims that all NOAA’s adjustments have done is increased warming by a modest 3 per cent, in actuality they have increased it by 35 per cent. So, far from Cowtan’s assessment that these adjustments are “inconsequentially tiny”, they are in fact quite massively distorting.

Might it be that they reached such wildly different conclusions by using different data? Er, no. Burton reached his conclusions by creating a spreadsheet with decadal data digitized from the exact graph used in Cowtan’s video.

Now I appreciate that in the context of the broader climate debate this might seem a trivial dispute. But I’ve been at this game long enough to be able to assure you that these faux rebuttals like the one offered by Cowtan are absolutely integral to the ongoing survival of the alarmist ‘consensus.’

As far as the warmist propaganda machine is concerned it really doesn’t matter two hoots whether or not Cowtan has got his facts right. What matters is that whenever the inconvenient subject of doctored temperature data crops up again, the alarmists have their ready-made get out. From a proper actual scientist. So he must know – right?

You can be sure that, if it hasn’t already, Cowtan’s dodgy rebuttal video will soon be linked to by the usual warmist sockpuppeteers in the comment threads below every relevant article. What none of them will mention, of course, is the Burton counter-rebuttal to the Cowtan rebuttal. Integrity has never been these people’s strong point. It’s winning the propaganda war that counts.

Meanwhile, in the real world, the case for a fraud trial against the climate data record gatekeepers seems to be getting stronger and stronger.

Paul Homewood, the blogger who noticed the discrepancies with the Paraguay temperature records, has now turned his attention to the Arctic region. His conclusion after studying the charts before and after is that the scale and geographic range of these adjustments is “breathtaking.”

In nearly every Arctic station from Greenland in the West to Siberia in the East, the data has been adjusted to make the warm period in the 1930s look cooler than it actually was. This, of course, has the effect of making the Twentieth Century warming look much more dramatic than the raw data would suggest.

Will this scandalous apparent evidence-tampering ever get much coverage in the mainstream media? It certainly ought to. Think about it: if Homewood (and Anthony Watts and Steven Goddard, et al) are correct, then what it essentially means is that the entire global warming scare has been sold to us on a false prospectus.

But it won’t, of course, because the mainstream media – in large part, at least – remains wedded to the Man Made Global Warming orthodoxy and therefore only really likes to run stories that prove how totally wrong, evil, and swivel-eyed climate change deniers are.

For example, this story in Nature, which sought to explain away one of the most embarrassing problems the warmist camp has been suffering of late: the abject failure of their fancy computer models to have predicted the planet’s failure to warm since 1998.

According to the lead author of this widely reported study, one Jochem Marotzke of the Max Planck Institute, it dealt a fatal blow to the sceptics’ case that the warmists’ computer models were a waste of space.

Unfortunately for Marotzke, his case has now, in turn, been demolished in this article by Nic Lewis.

Professor Gordon Hughes, one of the statisticians who reviewed and confirmed Lewis’s findings has commented thus:

“The statistical methods used in the [Marotzke] paper are so bad as to merit use in a class on how not to do applied statistics. All this paper demonstrates is that climate scientists should take some basic courses in statistics and Nature should get some competent referees.”

Damning indeed.

But here’s a prediction. The rebuttal won’t receive nearly the coverage that Marotzke’s original inept paper did.