Sunday
Aug152010
by 
Bishop Hill
Bishop Hill Here come the cavalry...
Aug 15, 2010 Climate: Statistics This thread is for discussion of the McShane and Wyner paper, which looks as though it is going to be a pretty significant contribution to the Hockey Stick debate. Well, it has got Real Climate deleting comments again anyway...
Reader Comments (113)
While very interesting and encouraging, this paper must itself also stand independent scrutiny. However, it looked very good to me, but I haven't been in statistics for a long time.
I suggest taking a trip through the 159 and 275 comments (counts as of 1200 hrs PDT) at Climate Audit and WUWT respectively. Very informative. A few of the CA trolls took their shots on WUWT and were soundly thrashed for their efforts. The McShane and Wyner paper is very clear even for someone who took his only stat class in the Late Pliestocene.
A big OOOPs. Should read "A few RC trolls..." SM has no use for or need of trolls.
I have been following all the discussion on this paper at WUWT - one key point seems to be that the paper does not try to question the validity of the data used by Mann - does not try to suggest that it is cherry-picked etc - it simply takes exactly Mann's data and shows by using proper statistical method that there is no provable Hockey Stick.
In other words - even if Mann had not cherry-picked, his statistical ability is rubbish.
From which I conclude - as the whole AGW case is based on statistical analysis of temperature levels - there is no AGW case.
...................
The paper looks hugely important. Needs to be picked up by Booker et al - we can assume the BBC will pretend not to notice it.
The article details a more statistically robust approach to generating a long temperuture record based on the proxies available in Mann08. McShane and Wyner very carefully create more reliable ways to construct the record and avoid numerous issues with overfitting that appear to plague Mann's approach. They take the Mann proxy data set as a given. They do not try to assess the quality or defects of individual proxies. They therefore leave the Tijlander series as defined by Mann plus problematic Cedars and BCPs. Theirs is an analysis to define better statistical procedures when too many variables for the number of data points and autocorrlation issues.
While the technical details are challenging, the article is written clearly enough that anybody who has been following the GS controversy can grasp.
The bottom line is that they demonstrate that the existing procedures fail to accurately reflect the actual uncertainty in any reconstruction and that more robust and appropriaate techniques do not generate the type of HS that has become iconic.
Wyner is a well established statistician. McShane is a new PhD. Wyner was McSHane's thesis adviser. The work of McIntyre and McKitrick is referenced in a very positive way. The work of Mann et al is treated less sympathetically and more critically. .
Wyner dropped by CA, so I am hopeful that he will stay in this discussion. He indicated that the JAS is going to run a special issue with invited responses.
We should expect strong rebuttals from Tamino and Ammann. The authors are not climate scientists and they may not be aware of the complexities of the data set, so I doubt very much that this is the last word by any means on the HS.
I particularly liked the comment on WUWT ; " what would the graph look like if Yamal and Tiljander were NOT used"? Hmmmm, well within natural variability methinks. Sad that it took so long ( and so much money) to come back around to what the realists have been saying all along. I am certain Mcshane and Wyner were well aware of the scrutiny (as is proper in real science) this paper would receive. You do not go into the lions den unaware of how the lions are going to react.
The acolytes at RC have already proclaimed them to be B-grade academics and that their paper is full of political undertones ...
One political undertone, Harry, would be the statement:
"Nonetheless, paleoclimatoligical reconstructions constitute only
one source of evidence in the AGW debate."
It seems the authors didn't want to be the ones who put the final boot into AGW. Other than computer models, which are not in themselves evidence, what would these other sources be?
Bishop I love your title here - quiet ref. to Bannockburn, the way I read it.
History tells that the Scots and the English were fighting at Bannockburn, the Scots under Robert the Bruce, outnumbered by the English 3 to 1 and mainly on foot. Legend says that they were about to lose the battle when a large contingent of Templar knights arrived on horseback and turned near-loss into victory. Historians rubbish the legend - but to my terrier-style digging for evidence, their rubbish can all be answered. And whatever the truth, the icon of this sudden miraculous arrival of Templars who saved Scotland for the Scots is very powerful.
Now we have McIntyre, McKittrick and McShane fighting for freedom. And Monckton of Brenchley. All Scottish titles. All expert cavalry chargers. All suddenly appearing in full force over the last week or so.
My perspective on this seminal statistical paper can be found here. Summary: the bottom just fell out of global warming 'science'.
Cheers, AJStrata
Did they ever stop?
I regret to say but this paper is not the cavalry charge that will sway the battle. There will be just more arguments amongst statisticians ad infinitum. The cavalry charge will come when physicists will provide experimental or observational proof within the known laws of physics of the insignificance of CO2 warming.
George -- hasn't Miskolezi done just what you say is needed?
Tamino has now allowed the evil title to appear in his blog, with many of his catomites pleading that he refute it soonest.
RC has a more measured wait-and-see approach. I guess to see if they can hijack it to their own purposes.
JohninLondon
Maybe the RC crowd saw this one coming because for at least a month all the usual suspects have been telling us that the Hockey Stick does not matter.
The AGW proposition rests on two pillars:
First that warming in the 20th century was unprecedented.
Second that 20th century warming can only be explained by Greenhouse gas emissions.
McIntyre, McKitrick, McShane, Wegman and Wyner have now all piled in and basically said that paleoclimate reconstructions are not reliable enough to erase the Medieval Warm Period from history.
Their efforts now leave us with:
The Medieval Warm Period.
The Holocene Maximum.
The last four Interglacials.
ALL warmer than today.
This leaves the warmists fighting on only one argument: 20th century warming can only be explained by man's Greenhouse Gas emissions.
Come on folks this is where we kill them ^.^
JohninLondon
it simply takes exactly Mann's data and shows by using proper statistical method that there is no provable Hockey Stick.
In other words - even if Mann had not cherry-picked, his statistical ability is rubbish.
You have put your finger on the EXACT point of the paper. I might also add that they were clever enough to archive the VERSION of the data they used as the "on-line" version appears to change from day to day.
The reason why I said this paper needs to stand the test of critical review -- which is not peer review, but the actual review of the statistics community at large -- is to solidify their opinion of the work. From what I have seen in the past, and based on my ancient knowledge of the field, Mann was is La La land when it comes to statistics. However, who the hell is Don Pablo? Just some retired dude. On the other hand, if the statistics community at large says that Mann is wrong, then that will have a real impact.
Harry
The acolytes at RC have already proclaimed them to be B-grade academics and that their paper is full of political undertones ...
At one time there was a clerk in the Swiss Patent Office with some ideas about gravity and such. He wasn't even an academic. At the time, that is.
Wyner is no Grade B, however. He is at the Wharton school, not exactly your bush league. He is young, bright and out to make a name for himself. And he is smart enough to be very careful. The paper shows that. The paper is VERY, VERY methodical and focused.
Once again, that is why I am saying critical review of this paper by the statistics community is important. I read most of the 45 or so pages. I think they have it nailed, but I could have easily missed something. If fifty or so statisticians say that it is correct, then the Mann made hockey stick is broken.
Lucy Skywalker--
Legends concerning the Knights Templar at Bannockburn in AD 1314 recall the "Angels of Mons" six hundred years later. Alas for such tall tales, King Philip IV "the Fair" of France took executive action to retire his debts to the Templar banking confraternity by persecuting its members unto death en masse beginning Friday 13, 1307. At Medici competitors' behest, Pope Clement XII (himself a Florentine) formally disbanded Grand Master Jacques Moulet's leaderless Order from Anno 1312.
Two years in dendrochronology may count zip-squat, but human history moves by febrile fits-and-starts. By sad coincidence, 1313 corresponded with an abrupt climatic end of the Medieval Warm, entering 10 - 15 years of cold and famine that tipped western cultures into the catastrophic 14th Century "when God slept." Notorious for its internecine warfare, apocalyptic demographics, cataclysmic plagues, the ensuing pre-Renaissance period began a 500-year Little Ice Age which ended barely 125 years ago. Quite possibly, by 2113 we will find that Gaia has been "warming up" for a 102,000-year resurgence of Pleistocene Ice Time, a cycle occurring regular-as-clockwork over the last 2.6-million years.
The hockey team will deploy their usual defense: ad hominem attacks, pseudo-statistical chicanery, obfuscation, and the security blanket of "replication" by other team members. So, this too will pass - the hockey team, remember, is a concatenation of self-deluded, crusading loons. The quotation below neatly encapsulates the world inhabited by the team:
I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.
Leo Tolstoy (1828 – 1910)
But how wonderful to see the efforts of McIntyre and McKitrick validated and vindicated.
DPdlS - "I might also add that they were clever enough to archive the VERSION of the data they used"
It can't be classed as a Climate Science paper then.
The significance of the McSHane ans Wyner paper is not whether RC can weasel their own interpretation of it. The significance will be for the next IPCC report ( AR5? AR6? I lose track)
The IPCC must now express the fundamental uncertainties in the paleo reconstructions as demonstrated by this paper. That's a big chunk of "evidence" which will need to be rewritten for the next report and will rightly draw the comments such as,
"Well you were wrong about all this paleo stuff back then. Why should we believe what you say now?"
GrantB
It can't be classed as a Climate Science paper then.
It never was intended to be a Climate Science paper. It is a Climate Statistics paper. However, it does have very serious implications on Climate Science.
I think JohninLondon did a great job of summarizing that above.
It is not an examination of the data, or how it was collected, modified, cherry picked or any of that. What McShane & Wyner did was to take a set of the Mann data and analyzed it using various statistical tools, and they made sure that the fanboi in green wouldn't try to confuse the issue by changing the data, which they have archived for others to use, if they wish. Thus the issue is: Is the statistical treatment of the data -- whatever it may be -- correct, and are the interpretations of that analysis reasonable?
While the paper is very long -- 45 pages or so -- they wrote a very readable paper that most people with some knowledge of statistics can easily read and many others can get through. It is a brilliant piece of work. It cuts right to the core of the issue about the analysis without getting bogged down on all the other issues.
The result is that the analysis done by Mann et all is basically bogus, and Mann's interpretation unreasonable. Then they go on to make their own interpretation of the data Mann used.
Dung does a nice job of summarizing that interpretation and its implications above.
Basically, if supported by other statisticians such as VS, then this paper puts a wooden spike right through the heart of the Hockey Stick and AGW.
It is a key paper -- a very key paper unless McShane and Wyner made a serious mistake -- which I doubt.
We now have the evidence in this paper MW2010 that we are not in a period of exceptional warmth with an exceptional warming rate. We now have the evidence in MMH2010 that the climate models are all invalid by a factor of two to four. The crux of the CO2 hypothesis with its positive feedback is a failed hypothesis. The argument of ignorance that only CO2 can explain the recent warming is now blown out of the water.
Dung says "This leaves the warmists fighting on only one argument: 20th century warming can only be explained by man's Greenhouse Gas emissions. Come on folks this is where we kill them".
I believe the warmists have no arguments left; their locker is empty.
I agree this is where we kill them. Keep the pressure up on your MP, ministers, the media, your friends and colleagues. Sock it to them! ^.^
AGW is not dead yet, if you can't forecast correctly then forcast often and eventually you will get it right
http://www.guardian.co.uk/environment/2010/aug/15/climate-change-predict-next-disaster
Reading the paper, and not being a statistician but I'll give it a go. The crux is in section 5.5 model validation.
If I was a contrary sort I'd argue that the failure to forecast the sharp rise in the second holdout period (most recent) could be explained by a change in climate domain. By change in domain I mean that a chaotic climate process as segued to a new quasi-stable state where the previous rules don't quite work the same way. It doesn't need to be massive change, just a change in the crucial bits of data - and their relationships - used in developing the model.
The forecast model is calibrated using a particular climate domain 1850 - 1968. The inherent assumption is that the relationship between the physical components (proxy data etc) is fixed over the entire hindcast and forecast period. If the forecast climate domain is different - and we have the evidence of failure of tree-ring proxies since the 60's, as well as increased CO2 - then I don't see why the model should be accurate for forecasting in a different domain.
Their comment
if a model cannot predict the occurrence of a sharp run-up in an out-of-sample block which is contiguous with the in- sample training set, then it seems highly unlikely that it has power to detect such levels or run-ups in the more distant past
seems to my reading to assume that the present, future, and past climate domains are the same.
The statement 'hide the decline' was because they couldn't explain the deviation from proxy to measured - so much so that proxy data from 1960 onwards is no longer used.
Jerry Acting Devil's Advocate
Nice timing I guess:-
US Government in Massive New Global Warming Scandal – NOAA Disgraced
http://www.climatechangefraud.com/climate-reports/7479-us-government-in-massive-new-global-warming-scandal-noaa-disgraced
There are many subtleties in the paper, such that it works on many levels. For those without imagination it will pass them by, but they do not distract from the message.
It is a very focused paper. The phrase "less is more" is appropriate here.
And conceding to "the opponent" the rules of the duel is a masterstroke.
Jones: Don't panic! ... Don't panic!
Mannwaring: I am glad you spotted that McShane Wyner*
*British TV cultural references
We'll have to see what the "citizen statisticians" in the scientific community come up with by way of refutation. After all they're the first to point out that anyone without a degree in climate science has no business questioning their pronouncements. Let's see if their views on this are symmetric.
Philipp and Don Pablo, I don't share you're optimism, we are dealing with a religion here not a scientific discussion. As I've said elsewhere, neither christianitiy nor islam were conspiracies, but they managed to grow to the point where they had enough adherents to wage war. Both religions are riddled with easily disproved assertions, but both are still flourishing where poverty abounds and both are based on the basic tenet that humans are intrinsically evil and must change their ways if they are to enter the kingdom of godand will be punished.
Now what is the basic tenet of environmentalism? It is that humans are intrinsically evil and that unless they change their ways they will be wiped out by Gaia. It's a seemingly strong genetic message in some of our species to believe we're evil, and to support religions that espouse that view in the face of clear evidence that the religions are using data that is easily refuted to make their case.
Being a religion they have done what all religions have done over the years they have got control of the communications channels to the hoi polloi, and refuse debate or discussion. To the extent that there is palpable shock on the BBC if anyone dares to say they don't believe in the religion. There are a few newspapers bold enough to put the evidence to the people, but most either support the religion, or don't want the bother of being inundated with complaints.
We've a long way to go to even get to the state where these people can be challenged in public on their "science" they have prepared the ground well, it has been going on since the mid eighties and the ground they've made while we were sleeping won't be given up without a fight.
geronimo
I didn't say I was optimistic about the outcome; but we have to keep the pressure up and there is no time like the present. We have to show that "climate science" is a religion and not a true science. You don't plan the future of the country, and indeed the world, based solely on religious beliefs - well I for one don't.
johninlondon 2.23 am: "This leaves the warmists fighting on only one argument: 20th century warming can only be explained by man's Greenhouse Gas emissions. Come on folks this is where we kill them ^.^"
The proof is in AR4, a 2007 paper by Kiehl in 2007 and more recent papers. The over-prediction of the GCMs is offset by assumed 'aerosol cooling', mostly clouds ['polluted clouds have smaller droplets so have higher albedo']. Without this assumption the models are meaningless. The 3-fold range of this correction greatly worried Kiehl but he thought that as CO2 rose, the AGW signal would rise above the noise. However, there is no general experimental proof of the effect. Therefore, the models and/or their calibration is wrong.
This faith in the 'cooling Twomey effect' came about because clouds above 'ships' tracks' are brighter, but they are thin clouds and the theory, increased optical depth for more, smaller droplets, only applies to thin clouds and predicts maximum albedo of 0.5 with no directionality: in reality albedo can reach 0.9 and is directional. The climate scientists are worried: a recent paper suggests polluted clouds have 30% lower water content; another, by Lindzen no less, suggests they freeze at lower undercooling; intriguingly, a further paper quotes an 'anti-Twomey effect' for monsoon clouds.
The water was muddied when NASA put out in its literature an entirely false explanation of the assumed effect, specifically that more, smaller droplets have greater total surface area so reflect more solar radiation. This could be sloppy science but it could also have been a deliberate attempt to deceive. There is a second optical effect at the top air/cloud boundary. You can see it with the naked eye. It's an astonishing bit of physics from Maxwell's equations and it explains high, angular-dependent albedo plus a positive droplet size law and an important role of size distribution.
geronimo: we are dealing with a religion here not a scientific discussion.
I think it is entirely possible that in two thousand years we will still be making sacrifices to ward off the imminent arrival of the Global Warming Catastrophe, so eloquently prophesied by Saint Phil and Saint Michael. And still paying our tithes at Met Office Cathedral.
Geronimo makes the point that seems to have been missed by many commentators. AGW is a religion to many people. There are, of course, the parasites, like Al Gore, and the careerists who fear they will lose their grants but I believe the majority are driven by political and social beliefs. Once worthy organisations like Greenpeace, Friends of the Earth, WWLF have long been subverted by entryism and promote an extreme left wing agenda.
Like religious zealots, reason and truth has no place in the argument. If you 'believe' then only facts which support your case can be considered. Rational reason is ignored and if it cannot, it will be scorned and vilified.
It is apparent, also, that western governments; European in particular, have not in any way modified their stance in view of increasing, and incontrovertible evidence which we are now seeing,
The battle is, I am afraid, far from over.
AGW is dying.
No evidence to support unprecedented temperatures.
No evidence to support climate models.
Statistician have damned the climate liars.
It would appear that NOAA have knowingly kept secret that their NOAA-16 satellite has been faulty in that satellite temperature readings have been degraded for some considerable time. The recorded temperatures are too high.
NOAA's claim early this year that 2010 will be the hottest year on record is now in serious doubt.
http://www.revolutionbroadcasting.com/?p=692
"New Zealand’s NIWA sued over climate data adjustments" now running on WUWT could prove interesting.
I agree with those observers that note that the AGW religion will certainly survive this paper. One thing history has shown is that a religion can exist and even thrive, completely unhindered by a lack of scientific evidence to support it.
On the bright side, though, mankind in the West has broadly moved into a more secular mode in the last few centuries and although religion will likely never die, congregations will be unlikely to grow. AGW is a religion that has masqueraded as science - and science, in preference over faith, is attractive to those of a scientific disposition.
Unlike most religions, the previously substantial AGW congregation, that mistakenly understood their pursuit was scientific, will probably discard AGW when they come to understand exactly how little scientific substantiation it truly enjoys. Though there will remain a congregation of true believers, their voices will be lost in the noise, amid the voices of religious extremists and bizarre conspiracy theorists.
OT
I am not sure if this very favourable review of The Hockey Stick Illusion has been mentioned at this site :
http://www.quadrant.org.au/magazine/issue/2010/7-8/the-tree-ring-circus
If it has been posted earlier - I apologise.
Where did this Knights Templar tosh appear from? When I was in short trousers, the yarn was that the day was saved at Bannockburn when the sma' folk appeared over the ridge. I can't remember whether they were led by a McIntyre, but it's entirely possible.
"One thing history has shown is that a religion can exist and even thrive, completely unhindered by a lack of scientific evidence to support it."
Yup. They all have so far.
Whilst the basic religion may very well live on, I am looking to, on one hand, the graft and corruption of the various carbon markets to sicken enough good people to see them fall into disrepute strong enough for it to be political suicide to continue to back them; and on the other for the massive costs (tithes) demanded (as in Kyoto) to render them unaffordable in the present and projected economic situation.
The UK government appears today to be backing away from any immediate banning of coal fired power stations. This is infuriating the true believers; but I guess the reality of cost has struck the government.
This, and the continuing questioning of the science, holds hope. It will not deter the fanatic; but it will take the gloss of super-profit away, and thereby lessen the attraction to the fraudsters; and it will cause the balance of the conregation to pause. As such pauses become more frequent, the religion will shrink in upon itself until it becomes only an irritation to the rest of us.
Jerry, I think the authors cover your particular point directly:
“On the other hand, perhaps our model is unable to detect the high level of and sharp run-up in recent temperatures because anthropogenic factors have, for example, caused a regime change in the relation between temperatures and proxies. While this is certainly a consistent line of reasoning, it is also fraught with peril for, once one admits the possibility of regime changes in the instrumental period, it raises the question of whether such changes exist elsewhere over the past 1,000 years. Furthermore, it implies that up to half of the already short instrumental record is corrupted by anthropogenic factors, thus undermining
paleoclimatology as a statistical enterprise.”
Philip,
You're right I was just putting the point that you can't celebrate a victory until the final whistle. So far they have sailed through Wegman, Climategate and the Hockeystick trick unscathed, many more battles have to be won before the politicians have the courage to face down these scientific activists. Keep going forward, be optimistic and realistic.
I'm pleased to see the government has seen sense over coal fired and nulcear power stations there is a danger that the lights will go out in this country if we don't start building generating stations PDQ. Part of the problem of having politicians who've never worked a day in their lives or run a business is that they think that there is technology to solve every problem, which is true to some extent, but in the case of the generating stations carbon capture and sequester, favoured by the greens is many years away, and even then poses problems in storage, while nuclear power will only be safe if and when fusion is developed. Wind and solar are pretty useless too, and will take decades to get to a point where they can provide sufficient power efficiently, if they ever do. At least there appears to be pragmatism in the government's approach which is to be welcomed. I can only think that Chris Huhne has been overruled, I can't see him wanting to be pragmatic, given his previous dogmatic statements.
Cumbrian Lad,
Thanks - I was getting very worried that my point was going over the heads of most readers.
I regret I missed that bit of text in the document you quoted. However it is vitally important. The effect is that either regime change (or my term - domain change) is happening or not.
If it is happening - and I suspect so - then proxy methods are virtually useless.
The outcome is that there must be a recognition that regime change is occurring and that forecasts based on historical evidence are dubious. In particular statistical forecasts, but in general numerical forecasts that rely on historical data for calibration.
Jerry, et al - there is a real simple explanation why tree rings and other proxies fail to detect large or rapid spikes in temperature. Basically a tree (and I would argue many other natural processes) are either on or off based on a temperature point - a trigger. Once temps get to a certain level trees grow at a peak rate. Adding temperature doesn't increase the rate at all, so what you have is banded growth rates based on ranges of temp and other factors. In fact, high heat and low water could look like near freezing conditions and plenty of water in trees.
The current 'divergence' could be absolutely accurate for tree ring behavior on these ridge line plants. Once the average temp hits a point the max growth rate is achieved and no amount of additional temp can increase it - the system is saturated at max output. Same with cold. Trees are dormant below a certain range and therefore cannot indicate any temp at all.
What this means (and what MW2010 is showing) is that proxies are only good in a narrow range, outside of which they become completely moot. It means proxies cannot reflect or show temps outside this range - which is why the damn stick is so flat!
The truth coming out is that climate scientists on the AGW side are just not aware of the complexity of the systems they are dealing with, and their simplistic models show it.
I keep thinking that "there will be religion" and maybe a third of us will be caught up in it. So expecting a religion to dwindle is to ignore history. Instead look for substitution, replacement., or absorption.
Someone will devise a "bigger lie" which will incorporate the disparate beliefs and faiths that now flourish in one sweeping universal (where have we encountered universal before) amalgam which explains everything to the folks who don't know how to ask the question.
AGW doesn't seem to have the legs to take over the world but if you could simplify AGW, Bio-diversity, Peak-Oil, and the others into one simplistic mantra that is something other than "We be bad" you might have something.
We're probably fortunate that Al Gore isn't smart enough to think of it.
Cumbrian Lad,
My prediction for 'them of the other persuasion' is that they will conclude that climate regimes are changing, but that historically it has been pretty constant and that it's only the perturbed time period from the 60's onwards that's a problem - if not a major bonus by showing man made climate change.
There is an interesting insight posted in CA yesterday when Abaraham Wyner dropped in for a cameo appearance @ Aug 14, 2010 at 8:34 PM. He said little, but it was very revealing:
At least one of the other posters (I am sorry I can't find it in that mish-mash listing) realized that the paper has had to been privately distributed for comment by the journal sometime ago and it was highly probable that the Hockey Team was aware of McShane & Wyner for sometime and that might explain the sudden change in their defense of the the Hockey Stick ( "It's not that important!") as well as change to "Climate Change™" and perhaps "Biodiversity™" tactics.
I think that poster, whomever it was, had it right.
I would suggest you order your copy of that issue Annals of Applied Statistics now. It will be a best seller and will undoubtedly sell out in a few hours. :)
Jerry/AJ I think the point the authors are making is that one can posit a change in regime, but there is no evidence one way or the other. One may suspect it, but the evidence would not come from the papers under discussion.
To my mind, the use of Mann's HS with the instrumental record attached has always ben a matter of mixing two methods with a completely different resolution. The resolution on proxy data (never mind the noise in the data) is not good, it does not show fine detail. The instrumental record is much finer, but does not have the length of record required. The paleo reconstructions, perticularly with error bars as big as they now look to be, tell us nothing about the fine structure of climate patterns. 'Regime change' in this context means nothing. We may see fine changes in current data, but we have nothing to compare it with in the past. We could look at 'local' records such as the CET record, or the Armagh data, which are the longest we have -they show no indication of regime change. Much more probable is that such changes as are seen in the synthesised global instrumental record have occured many times in the past - we just can't see them that far back.
Or more simply, use the correct tool - don't use a telescope to count microbes, don't let your ship's look out use a microscope, and don't mix the two (or your metaphors!)
The Global Warming Scare has run it's course. The public are bored senseless, they have moved on to more important matters of concern.
Of course there will a be a few diehards, the uber faithful, and there will be the political legacy, the mess that others will have to clean up, and the lasting damage to science, but the game is up.
We are all sceptics by default.
Cumbrian Lad,
I am not sure what you mean by 'regime change' precisely. I agree the graphic splicing of temperature data on proxy data was incomprehensible. I cannot fathom such nonsense. The only reason (and given by the hockey team themselves) is to hide the decline (or divergence). The proxies basically stopped tracking temps after 1960.
Which goes to my hypothesis. Plant growth is not linear, it looks more like a Fourier step function (which is actually true of many biological systems and responses - just look at a neuron response to current). The dependent response changes based on the range of the independent forcing function.
In plants, growth below a certain average temp (and day length) is flat. The plant is dormant. The next domain is above the trigger point where seasonal growth occurs. In this range you would see linear rise in growth for a while, but an asymptotic plateau would arise as all factors combined into the optimum conditions and the plant's growth is limited by biology, genetics, etc. There is a maximum growth rate for all living organisms.
Above that optimal range you would see decaying growth rates leading back into a dormant state (which many plants revert into in cases of drought).
This is plant physiology 101. There is no linear connection between temp and growth - none! Moreover, plant growth is a multi-dimensional product of many factors. You cannot hold all factors steady in the historic record (though you could in the modern 'training' period of the models) and pull out temp. Number of sunny days (Solar Irradiance hitting the leaves), Canopy, soil nutrient levels, water levels, etc all impact growth and produce various growth patterns for any single given temperature value.
If the temp signal only has an effect in a small range of conditions (both temperature and other factors), outside of which growth is steady (either dormant or maxed out), then these proxies do NOT indicate large fluctuations - which is why the LIA and the MWP always disappear. These proxies are unable to detect anything outside their small window of temp sensitivity.
I think that is what this report PROVES, that paleoclimatology is now a busted science.