The other day, a reader at Climate Audit quoted an old Maclean's column of mine from 2009:

The famous hockey stick graph created by Dr. Michael Mann played a critical role in persuading millions of people we're all gonna fry. In the National Post of April 2, 2001, after the UN had adopted this graph as the official proof of global warming, I pointed out that the first nine centuries of the millennium were measured by using tree-ring cycles, and the modern era was represented by temperatures. Now I'm not a climatologist. I'm not even a railroad engineer. But, if you show me a graph that looks like a long bungalow with the Empire State Building tacked on the end, I'll go, "Whoa! That looks pretty serious. We better head for the hills." If it then emerges in the fine print that the bungalow was created with one unit of measurement and the skyscraper another, I'll postpone my departure and go, "Er, hang on, what's the deal with that? If we've got tree rings for the first nine centuries, why can't we stick with the tree rings through the 20th?"

To which Steve McIntyre tsk-tsked:

His understanding of the issues in 2006 was more accurate. The 1998 version of the Mann hockey stick used proxy data in the 20th century. ironically this criticizm would be more apt if applied against Mann et al 2008 which did splice instrumental and proxy data in the reconstruction. But you have to take care to be very precise in what you're saying as inaccurate criticisms give straw men.

In fairness, I think I was referring to the IPCC version, which uses, exclusively, proxy data for nine-tenths of the graph and then folds in actual temperatures for the 20th century. But Mr McIntyre's last sentence is a valid point, especially when there are so many Mann hockey graphs out there, all with different dodgy fixes to prop up his flaccid stick (I was amused by Steve's reference an inch or two below to what he calls "the first generation of Hockey Stick issues"). Even Mann seems to have difficulties keeping his various sticks straight: I'm reminded of the Hollywood screenwriter William Goldman's book, Which Lie Did I Tell?.

However, a new post at Climate Audit discusses Mann's current hockey stick - the 2015 model, as published in his latest piece of peer-reviewed self-glorification in The Bulletin of the Atomic Scientists. And, if you look at closely at Figure One (right), you'll see that Mann, right now, is doing exactly what I accused him of 14 years ago. As Steve McIntyre writes:

First, here is Figure 1, entitled "Hockey stick graph" of rising global temperatures. Sharp-eyed readers will notice that the Figure goes to 1998 or so, and that it grafts the instrumental record after 1902 onto the proxy record before 1901, with the grafting not mentioned in the caption.

To reprise my original criticism:

I pointed out that the first nine centuries of the millennium were measured by using tree-ring cycles, and the modern era was represented by temperatures... If we've got tree rings for the first nine centuries, why can't we stick with the tree rings through the 20th?

So, amazingly, I'm just a year off. I accused Mann's hockey stick of using tree-rings for the first nine centuries, whereas he keeps them all the way until 1902, which is in the 20th century. And then he junks the tree-rings and grafts the actual 20th century thermometer readings onto his pre-1902 proxies.

Which, oddly enough, is something he says he never does:

No researchers in this field have ever, to our knowledge, "grafted the thermometer record onto" any reconstruction. It is somewhat disappointing to find this specious claim (which we usually find originating from industry-funded climate disinformation websites) appearing in this forum.

And yet here he is in 2014 "grafting the thermometer record" onto his "reconstruction" in precisely the way I accused him of doing in 2001:

1000-1901 reconstruction;

1902-1998 thermometer record.

Did he get the idea from me? Should I counter-sue him for plagiarism?

At any rate, I've previously noted that the settled science has taken five years to catch up with one of my throwaway lines. So I'm even more heartened to see that what Steve McIntyre regards as my carelessly worded critique of Mann's malfeasance in 2001 nevertheless holds up better in 2014 than any of the climate models from 13 years ago.

~While waiting for the Mann vs Steyn trial of the century to begin, I'm honored to be joining Steve's co-tormentor of Mann, Ross McKitrick, plus some of the most eminent scientists (and fellow troublemakers like Nigel Lawson, Donna Laframboise, Andrew Bolt, Joanne Nova, and James Delingpole) among the contributors to a brand new book put together by the Institute of Public Affairs called Climate Change - The Facts. I'll have more to say about it in a separate piece, but it's hot off the press and available in Kindle at Amazon.com and at Amazon outlets worldwide. I hope you'll check it out. It's well worth your time.