Hey Ya! (mal)

McIntyre has based his ‘critique’ on a test conducted by randomly adding in one set of data from another location in Yamal that he found on the internet. People have written theses about how to construct tree ring chronologies in order to avoid end-member effects and preserve as much of the climate signal as possible. Curiously no-one has ever suggested simply grabbing one set of data, deleting the trees you have a political objection to and replacing them with another set that you found lying around on the web.

The statement from Keith Briffa clearly describes the background to these studies and categorically refutes McIntyre’s accusations. Does that mean that the existing Yamal chronology is sacrosanct? Not at all – all of the these proxy records are subject to revision with the addition of new (relevant) data and whether the records change significantly as a function of that isn’t going to be clear until it’s done.

What is clear however, is that there is a very predictable pattern to the reaction to these blog posts that has been discussed many times. As we said last time there was such a kerfuffle:

However, there is clearly a latent and deeply felt wish in some sectors for the whole problem of global warming to be reduced to a statistical quirk or a mistake. This led to some truly death-defying leaping to conclusions when this issue hit the blogosphere.

Plus ├ža change…

The timeline for these mini-blogstorms is always similar. An unverified accusation of malfeasance is made based on nothing, and it is instantly ‘telegraphed’ across the denial-o-sphere while being embellished along the way to apply to anything ‘hockey-stick’ shaped and any and all scientists, even those not even tangentially related. The usual suspects become hysterical with glee that finally the ‘hoax’ has been revealed and congratulations are handed out all round. After a while it is clear that no scientific edifice has collapsed and the search goes on for the ‘real’ problem which is no doubt just waiting to be found. Every so often the story pops up again because some columnist or blogger doesn’t want to, or care to, do their homework. Net effect on lay people? Confusion. Net effect on science? Zip.

Having said that, it does appear that McIntyre did not directly instigate any of the ludicrous extrapolations of his supposed findings highlighted above, though he clearly set the ball rolling. No doubt he has written to the National Review and the Telegraph and Anthony Watts to clarify their mistakes and we’re confident that the corrections will appear any day now…. Oh yes.

But can it be true that all Hockey Sticks are made in Siberia? A RealClimate exclusive investigation follows:

We start with the original MBH hockey stick as replicated by Wahl and Ammann:

Hmmm… neither of the Yamal chronologies anywhere in there. And what about the hockey stick that Oerlemans derived from glacier retreat since 1600?

Nope, no Yamal record in there either. How about Osborn and Briffa’s results which were robust even when you removed any three of the records?

Osborn and Briffa (2006) Supplemental Material

Or there. The hockey stick from borehole temperature reconstructions perhaps?

No. How about the hockey stick of CO2 concentrations from ice cores and direct measurements?

Err… not even close. What about the the impact on the Kaufman et al 2009 Arctic reconstruction when you take out Yamal?

Oh. The hockey stick you get when you don’t use tree-rings at all (blue curve)?

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