Steve McIntyre has a new analysis up, one that has a strong headline.
Though as he says, “not in so many words”, but more about techniques and exclusions. He writes:
Briffa Condemns Mann Reconstructions
Not in so many words, of course. However, Briffa et al 2013 took a position on the use of radially deformed tree ring cores that would prohibit the use of strip bark bristlecones in temperature reconstructions, thereby emasculating Mann’s reconstructions. And not just the Mann reconstructions, but the majority of the IPCC reconstructions used by Briffa in AR4.
I’ll report on this issue in today’s post. I’ve been looking closely at Briffa et al 2013 over the past 10 days and unsurprisingly there is issue after issue. According to CRU, they’ve been working on this article for over seven years and, needless to say, it is impossible to fully observe the pea in only a few days, especially when the adjustments have become so baroque that the chronology style is most aptly described as East Anglia Rococo, making the weary reader long for the classic simplicity of earlier CRU illusions like the Briffa Bodge and Hide the Decline. But more on this on another occasion.
full post here: http://climateaudit.org/2013/06/16/briffa-condemns-mann-reconstructions/
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When in doubt, bite your collaborator’s arse. That’s the sort of classy sh*t you’d expect of leather-tailed rodents abandoning a buoyancy-compromised aquatic conveyance, don’t you think?
I have always been puzzled by the picture of Michael Mann holding the cross-sectioin of a tree, presumably showing the tree rings he measured to get the proxy for temperatures in the past.
Is it THE tree that gave the upturn to the hockey stick? IT shows distinct damage at an early stage of growth (caused by felling nearby trees?) which could have restricted its growth rate, and then it could have accelerated growth in the absence of competition for light, nutrients and water. (Light and water availability have been the major influences in tree growth in my experience of growing trees). Along which radius do you measure it? There seems to be plenty of scope for cherry-picking.
Help me out here someone. Tree rings are believed to be reliable regional thermometers because……?
Your answer please in a paper of less than 5000 words that doesn’t take seven years to write.
tonyb
1975 and 1976 were both very hot and dry years, and resulted in very limited tree growth and thin tree rings in the UK. If temperature was a leading factor in tree ring growth, they would have been wider.
…………………Michael Mann says it is.
Mike, I think you could be a bit more tolerant: Keith Briffa has on various occasions been a bit of a doubter among ‘The Team’, i.e., he’s more of a real scientist, questioning things on the basis of his own research. Your comment attributes bad motivations to a person who we really don’t know, something that the AGW proponents do all the time. Let’s not!
I’ve long suspected that Briffa was actually a closet sceptic. I bet he had access to all the UEA emails.
Briffa in the emails asks a few hard questions of the others – he struck me as man who liked good science, had some doubts about how far advanced it all was … and likely just needed to make a living.
I don’t know any science but,two trees born same day,same year,
one in the middle of a field,one in the middle of the woods.tree in field,
short and fat,Tree in woods ,tall and thin.both with the same number of
rings. Are the rings the same thickness?
Alfred
1934 was one of the hottest years of the 20th century in the USA. The area where Mann took his samples was suffering from extreme drought in 1934. In Mann’s bristlecone reconstruction it shows up as a down spike. Was Mann actually recording rain and not temperature?
http://wattsupwiththat.com/2008/03/19/treemometers-or-rain-gauges/
http://climateaudit.org/2008/03/17/principal-components-and-tree-ring-networks/
I should have said:
Was Mann actually recording lack of rain and not temperature?
When they start turning on each other, the end is near…
Tree ring growth rate is limited by the least favourable parameter, be it temperature, moisture, sunlight, pests, soil pH, or whatever.
Tree rings might be usable as temperature proxies only if there were solid evidence that nothing else changed in the tree’s environment.
Otherwise we might find the proxy wandering off from the temperatures and we have to ‘hide the decline’ during the best periods of instrumental temperature records… or some such.
The settle science meme is starting to look a teensy bit unsettled. The smell of Napalm in the morning …
Pointman
How long before a Mann e-mail forces a retraction and a statement of blind and unquestioning faith in ‘the cause ‘ ?
climatereason says:
June 17, 2013 at 12:54 am
Help me out here someone. Tree rings are believed to be reliable regional thermometers because……?
===========
no,no,no. tree rings are believed to be reliable global thermometers. the way they know this is because they select only those trees who’s rings match global temperatures in a process known in climate science as “calibration” and known in statistics as “selection on the dependent variable”.
And while “selection on the dependent variable” is forbidden in statistics, because it leads to false and misleading conclusions, in climate science it has proven a positive boon and had been universally accepted after it was first introduced by a mathematician. and who better than a mathematicians to know how to lie with statistics.
If there was any field of science searching for false and misleading conclusions, it was climate science. The beauty of the technique is that intuitively it seems correct, and thus fools the majority of people. If you want to know if medicine A is effective, study people that take medicine A. 97% of people that take Dr Ferble’s tonic get better within 2 weeks. What Ferble isn’t telling you is that 100% of people that don’t take the tonic get better in 1 week.
What the calibrated tree rings are telling us is that temperatures are going up due to AGW. What the other tree rings are telling us is that tree rings are not good thermometers, that some trees will match thermometers simply by chance, and that any conclusions made on this basis are likely to be false and misleading.
http://www.nyu.edu/classes/nbeck/q2/geddes.pdf
Peter Hannan says:
June 17, 2013 at 1:29 am
“Mike, I think you could be a bit more tolerant: Keith Briffa has on various occasions been a bit of a doubter among ‘The Team’, i.e., he’s more of a real scientist, questioning things on the basis of his own research.”
I agree. Indeed, I think we should encourage identification of the (very) few among the main players of the last couple of decades that showed resistance to the “consensus”. They were not strong psychologically perhaps, under the threat of exclusion and its downside, but they have kept afloat. Phil Jones first voiced the 15yrs without warming but then he re-jigged the temp record called Hadcrut 4.
Gary Pearse says:
June 17, 2013 at 6:47 am
Phil Jones first voiced the 15yrs without warming but then he re-jigged the temp record called Hadcrut 4.
============
Temperatures in the past are decreasing due to AGW. Ever year that passes, the past gets colder and colder because CO2 levels are lower in the past. This process will continue, even if Jones has to redefine the meaning of absolute zero.
ferd berple says :
Temperatures in the past are decreasing due to AGW. Ever year that passes, the past gets colder and colder because CO2 levels are lower in the past. This process will continue, even if Jones has to redefine the meaning of absolute zero.
The team says: The models prove the earth is getting warmer. The places where we can measure the temperature are not getting warmer, therefore the missing heat is located where the thermometers aren’t. The heat is in the deep ocean. Deep oceans have gotten much warmer in the last 20 years.
The apparent acceptance of circular reasoning in science is a gigantic step backwards for western civilization.
climatereason says:
June 17, 2013 at 12:54 am
But the simple answer is – they aren’t good proxies.
The central tenet of tree rings as proxies is based on the assumption that all things (except temperature) remain constant. Which we all know is complete BS from personal experience (at least if you are over say 20 years old! – as we have all seen some warm and cold seasonal variation).
The other point is that in order to have such a proxy as valid – there has to be some kind of general consistency in the proxy you are measuring. So, for example, with tree rings, if we have easily identifiable zones of ‘consistent’ growth – we can then say that something changed when this consistency was broken. The crux of the matter then becomes – what changed? water, co2, ph, etc, etc. As in a lot of this proxy stuff, a few zillion assumptions are made!
With enough creative mathematics and enough cash from a host of government grants, surely the Lord of the Rings can find the true climate signal in there somewhere.
When you let the data lead you, you go remarkable places. Briffa seems to be finding that out.
The hockey stick is baroquen.
Briffa should have done this work about ten years ago. This has the appearance of a much belated attempt to retrieve his reputation from the trash heap. I do not sympathize with Briffa and others who belatedly realize that the global warming scam is not going to work and then try to salvage their scientific reputation. They chose years ago and now are trying to undo their mistakes. Do not forget, this Briffa has fought FOI and data requests tooth and nail, only to lose, and now that the ugly truth about his methods are exposed he wants to get right with decent science. Piss on him, we don’t need him.
This Briffa gripe is actually quite important. Two things: Mann really is a hack ‘scientist’ but a great self-promoter and grant vacuum. Mann’s value to real scientists is PR and rainmaking grants. But there comes a point where Mann’s abusive manipulation of real scientists’ work is too much, and maybe, Mann’s money highway is slowing down. If Mann’s not sharing the wealth, scientists like Briffa have no reluctance to dump on him, IMO. So this is very signifigant.