Wednesday
Jun162010
by 
Bishop Hill
Bishop Hill Andy Russell on the Hockey Stick
Jun 16, 2010 Climate: HSI Andy Russell, a climatologist from Manchester, has written a brief history of the Hockey Stick. He says he hasn't read the Hockey Stick Illusion, which is a pity because he hasn't really moved things forward at all. There are many things he gets wrong that are covered in the book.
I've suggested he gets hold of a copy.
(Andy's piece is not inflamatory and I hope anyone commenting there will reply in the same vein).
Reader Comments (8)
It's not a question of being inflamatory or not. Whenever I see a climatologist defending the hockey stick - and not showing the slightest understanding of the key issues, or even of trying to understand what they are - I have to dismiss the person as not being serious. It seems obvious that such people start from the given assumption that if the hockey stick (whichever version) wasn't fundamentally sound, the climate science establishment wouldn't have promoted and defended it. That is actually the way they tend to argue - "the IPCC this, the IPCC that".
So, why bother?
People often write blog posts like this from positions of extreme ignorance. Andy is not a paleo guy, so he's not speaking from within his own specialism. He has clearly done some reading - RC and Wiki may be his principal sources. He has reached some conclusions that are erroneous - if he reads the book he may draw different conclusions. We'll have to see if he's serious about this or is just a propaganda guy. I don't think we can tell either way at the moment.
Well, thanks for the mention! I wrote the post in response to a Science of Doom piece about IPCC 1990 that seemed to be suggesting that there was something underhand about the development of the science in this area, which I thought was not the case. You're right, I'm not a dendroclimatologist, but the post wasn't meant as a defence of the methodology employed by Mann et al. Even so, as an outsider to this particular field, it seems that the balance of evidence is falling on that side of the argument (but I'm sure there are questions that can be asked of those investigations too...)
Thanks, Andy. I think there is a cartoon in this just waiting to be drawn. See if I can winkle it out by the w/e.
Sorry Andy you don't need to be a dendro to realise what Mann has done. You don't even need to be a statistician, though it helps cast some light on the very weak and unconventional methodology.
In very simple terms, he concealed the fact that the tree rings, which he represented as being extraordinarily (to within 0.5ºC) accurate indicators of global mean temperature over between 600 and 1000 years, gave measurements that were inconsistent with actual temperatures between 1960 and 1998. I cannot see how anyone with an elementary grasp of logic can feel comfortable extrapolating from a recent proxy that does not match the instrumental record and claiming greater accuracy than he can demonstrate for the most recent period - can you?
Where it does help to have some basic stats is when it comes to Mann's later attempts to rewrite his papers, cherrypicking data to try to generate the same result without the discredited samples. The problem is that the data from these samples are not incorrect, they are just inconvenient, to use Al Gore's favourite word.
Climatology suffers from several fatal starting assumptions.
The worst is the hope that by studying something a lot and collecting roomfuls of information you will eventually understand it.
Defending the hockeystick is as if we are in the 1930's and 1940's and reading defenses of piltdown.
Jack Hughes
The worst is the hope that by studying something a lot and collecting roomfuls of information you will eventually understand it.
If they have "roomfuls of information", why can't they find it? From what I understand, they "misplaced" it all. :)