I awoke this morning, March 5th, to a sharp frost, after one of the coldest winters I can remember. And I awoke to the news that the Met Office has announced a new body of research, based on 101 scientific studies, showing that despite all appearances, despite the CRU scandal, despite the exposure of nonsense over and over again in the IPCC reports, climate change really is man-made. Well as Mandy Rice-Davies famously said, “They would say that, wouldn’t they?”. They have too much political capital tied up in the Great Carbon Myth to face up to reality.
Of course the authors of those 101 papers confirmed man-made climate change. They know that their funding, their access to learned journals, and their academic posts depend on toeing the consensus line, even as the consensus breaks up. The money in climate change is enormous. Tens of thousands of jobs depend on it. The oil majors have been converted to climate activism not because they believe the Myth, but because they have become rent-seekers for subsidies on “green energy”. I read recently that carbon credits are now just about the largest traded commodity in the world (no, Phil, I can’t source this for you — Google it yourself!). The phrase “Fools Gold” could have been coined for carbon credits. They are a non-commodity. They are something that doesn’t exist, based on a theory that looks more discredited by the day. But you can’t blame the Fools for clinging to their Gold to the bitter end, until it turns to ashes in their hands.
I have just been reading “The Hockey Stick Illusion” by A.W. Montford. It’s an account of the scientific disputes behind the debunking of the famous “Hockey Stick” graph, the key illustration of the IPCC’s Third Assessment report, which has now become the most comprehensively discredited scientific artefact since the Piltdown man. The story is amazing. I had read that the algorithms used by Michael Mann, the creator of the Hockey Stick, actually looked for that sort of shape, and would produce Hockey Stick graphs even from random data — from the Chicago Telephone Directory, if you like. But I hadn’t quite understood how.
You might think that putting together proxy temperature records was a pretty straightforward process of adding and averaging, but there’s much more to it than that. Trying to remember my Maths degree from 1965, I managed to follow Montford’s account, although I might have trouble explaining it myself. But some key points stand out.
The selection of the 20th century up-tick (whether intentional or not) starts with a statistical device called “short-centring”, which is a failure to put different series on a common average. After applying statistical measures like correlation coefficients, this results in disproportionate weight being given to any series with an up-tick — so the up-tick or Hockey Stick comes to dominate the result. Critics have actually demonstrated this by applying Mann’s methods to random data, and — Bingo! — a Hockey Stick appears.
But there’s more to it than that. When Ross McKitrick and Steve Macintyre, two Canadian statisticians, tried to obtain the source data to seek to reproduce the Hockey Stick, they were met with a stonewall approach not only by Mann and his co-workers (“The Hockey Team”), but by scientific journals who ought to have known better.
When McKitrick and Macintyre finally got the data, they found a host of anomalies. Mann and his colleagues had used limited data sources, for example dendrochronological records from bristle-cone pines, from small stands of trees in a a limited area, with (for parts of the period) as few as a half-dozen trees in the sample. They ignored or dismissed the views of other experts who questioned whether these trees were a reliable proxy for ancient temperatures. In some cases they interpolated data into the series. The statisticians found that if you excluded just two or three of these suspect series from the analysis, it reverted to the previously accepted model of paleoclimate, with a Mediaeval Warm period and no Hockey Stick effect.
One of the most striking points was that many of the tree-ring series actually failed to show any up-tick at all from around 1960 on, so the Hockey Team instead spliced on instrumental records for the late twentieth century. When challenged, they suggested that contemporary factors such as industrial pollution might have affected the post-1960 period. But a more like explanation would be either that the tree-ring series were not reliable temperature proxies at all, or that the late-20th-century up-tick did not take place. This was the origin of the CRU attempt to “hide the decline”.
Throughout the debate the Hockey Team claimed that their work was peer-reviewed. But a US Congress study in 2006, chaired by prominent statistician Ed Wegman, not only found in favour of Macintyre and McKitrick, but also showed that the Hockey team’s peer-revue process was largely incestuous and self-referential. Members of the Team worked together, co-authored papers, and peer-reviewed each others’ work. Their papers were not, generally, peer-reviewed independently, still less by scientists taking a different view.
And above all they were not peer-reviewed by statisticians. You had climatologists using extensive and highly sophisticated statistical methods, without (apparently) a full understanding of those methods. When statisticians like Macintyre and McKitrick and Wegman took a look, the whole House of Cards fell apart.
So beware of Warmists who talk about peer-review. Let’s never forget that the IPCC’s most headline-worthy alarmist claims — Himalayan glaciers, Amazon rain forests, African crop yields, droughts and hurricanes, sea level rise — turned out to be based not on peer-reviewed science, but on propaganda releases from ultra-deep-green NGOs.