Steve McIntyre's recent Ohio State University presentation is now available online. This is an excellent summary of the 'Hockey Stick' debate and the climate debate in general, which extends to 45 pages (including references).
The presentation concludes:
So where does that leave us?
In my opinion, there are serious and probably fatal problems with the main proxies used as supposed evidence against a warm MWP – the Graybill strip bark chronologies, Briffa’s adjustment to the Tornetrask series, the inconsistency between Briffa’s Yamal substitution and the updated Polar Urals series and so on. For every proxy that supposedly shows a MWP cooler than the present, there seems to be one that is just as good or better evidencing the opposite. For the California and Urals proxies so fundamental to the Hockey Stick, the ecological evidence is further evidence against the Graybill and Briffa chronologies being interpretable as temperature proxies.
The selection of proxies in studies displayed by IPCC seems to me to be biased against proxies with a warm MWP. IPCC itself does not carry out any independent due diligence of the type that might be expected in a prospectus. Further, in 2007, as in 2001, the authors involved in preparing the paleoclimate section were active parties in controversies and, in the end, IPCC Fourth Assessment Report strongly reflects their partisan point of view.
Is there a wider lesson here for engineers? We are often told that the “Science is settled”. But engineers, of all people, know that, even if the “science is settled”, the engineering work may have just begun. One would hardly derive the parameters for a chemical process from an article in Nature without an engineering feasibility study.
The most critical question in climate is the estimation of a parameter – is the sensitivity of climate to doubled CO2 1.5, 2.5 or 3.5 deg C? Or could it be 6 deg C or 0.6 deg C?
In some ways, the estimation of such parameters through the development of complicated computer models is reminiscent of activities carried out by engineers. One important difference is that climate scientists typically report their results in highly summary form in journals like Nature, rather than in the 1000-page or 2000-page engineering studies that an aerospace engineering enterprise would produce.
Viewed from this perspective, a remarkable aspect of the climate debate has been the seeming inability of the climate science community to narrow confidence intervals on this estimate. In 1979, the Charney Report (National Research Council 1979) estimated the impact at 3 deg C with a 1.5 degree range either way. In 2007, IPCC AR4 estimates are virtually unchanged. With all the improvements in scientific knowledge and all the efforts of climate scientists over the years, why has the improvement of these confidence intervals proved so resistant? I don’t know, but it’s worth thinking about.
Truth(tropospheric temperatures) and Beauty(bouy data) are all ye know and all ye need to know.
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If Ender could even summarise the alleged debunkings for me I would be grateful. And I don't mean vague references to AR4.
"The scientific basis part of AR4 goes into this in some detail. "
"this"??????
I wanted some EVIDENCE.
I didn't want any "this".
Now stop bullshitting everyone and come up with the evidence.
Well you said it was a SUMMARY of evidence.
But what I wanted was some evidence.
If you want to make some sort of link and tell me what you think is evidence then go ahead.
But for the Love of God man stop screwing around and lets have some evidence.
CAN..... WE..... HAVE.... SOME ..... EVIDENCE!!!!!
So far you have REFUSED to come up with any evidence.
I don't think its too much to ask that you come up with some evidence.
So how about some evidence.
If you claim that the IPCC has some evidence well clearly you are lying. But on the other hand you might disagree with that assessment.
So lets have that evidence.
And stop stalling.
Look I don't want to hang around here. I'm just coming back to see if you will continue to REFUSE to come up with the evidence.
And every time I come back here you continue to stonewall and filibuster on the evidence.
NOW FINALLY!!!!
CAN.... WE.... HAVE... SOME.... EVIDENCE!!!!
I don't think thats too much to ask.
The willfully blind cry 'Beware theNazi'.
Look, look around, perhaps you will see.
The problem the models all fail to foresee,
Is the uncertainty in optical path length T.
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Graeme Bird - "But what I'd just like for starters is some sort of evidence."
The scientific basis part of AR4 goes into this in some detail. No if you persist in this foolishness I will just respond the way I do to the really annoying computer users that fail to read the manual and blame you for their ignorance. What I politely say to them after many many hours of fruitless instruction is RTFM. In this case you can RTFAR4.
Ender why bother debating an illiterate arts graduate who's an unelectable shift worker. Someone who can only write GIVE ME THE EVIDENCE and pulversing ice age.
In fact he has been given the MWP drought reference and failed to read it.
What you normally find is that trumped up little nazis masquerading as noveau economists can't actually read. So you would have to work on his literacy as first port of call.
Lets just have some evidence Ender. Stop jerking around. We weren't after the pretense that you had some evidence. We were instead after the evidence itself.
Where is this AR4 and what within it do you consider to be evidence? And on top of that why are you referring me to a SUMMARY when what I wanted was the evidence itself.
You are getting too ambitious here. I would have been happy with one valid piece of evidence. You reckon you can refer me to a summary when I was just after one individual bit of evidence.
Of course if you can find CONVERGENT evidence with 3 or more lines of convergence then that can amount to proof and I'll be entirely won over.
But what I'd just like for starters is some sort of evidence.
In brief we want to know whether the warming from CO2 is powerful enough not to be a good thing during this brutal and pulverising ice age.
Graeme Bird - "The IPCC has not come up with any evidence for it."
You should really qualify that. The IPCC does not do research as they could not come up with any evidence. They rely on the work of scientists that have come up with evidence and which is summerised in AR4.
If you do not accept this then you are ignoring the work of thousands of scientists over the years. The fact that you accept the mostly non peer reviewed work of a handful of skeptic scientists shows much for your thinking. Nothing I say will convince you if reading AR4 doesn't. You have read it haven't you?
mikep - "MBH has not answered his critics in great detail. Indeed his results have not even been replicated because he has never disclosed the exact way he did things"
Which is a classic example of debunked points being repeated endlessly until they become the truth.
"I'm afraid Ender is winding me up again and making me more sceptical. Let's have some honest debate instead of evasions."
And no you are not going to draw me into another hockey stick debate that I am also not qualified to do. Post your questions on Real Climate or simply find where they have already been answered again and again.