by Steve McIntyre
For the benefit of new readers, we discussed some aspects of the “trick” at Climate Audit in the past. Obviously, the Climategate Letters clarify many things that were murky in the past. On the left is a blowup of IPCC 2001 Fig 2.21 showing where the Briffa reconstruction (green) ends. More on this below.
Figure 1 below is the original graphic showing the MBH98-99, Jones et al 1998 and Briffa 2000 temperature reconstructions. I think that it’s fair to say that this graphic gives a strong rhetorical impression of the proxy reconstructions all going up throughout the 20th century, lending credibility to the idea that the “proxy” reconstructions would also be responsive to past warm periods – and obviously not giving any “fodder to the skeptics” by revealing the divergence between the Briffa reconstruction and temperatures.
Figure 1. IPCC 2001 Comparison of warm-season (Jones et al., 1998) and annual mean (Mann et al., 1998, 1999) multi-proxy-based and warm season tree-ring-based (Briffa, 2000) millennial Northern Hemisphere temperature reconstructions. The recent instrumental annual mean Northern Hemisphere temperature record to 1999 is shown for comparison.
While the digital version of the Briffa reconstruction has only become available in the past few days, Briffa 2000 (cited in the caption to IPCC Fig 2.21) did show the decline as shown in Briffa 2000 Figure 5 shown below (with its original caption). This series obviously goes down at the end (as does a related series in Briffa et al 1998, referred to by Gavin Schmidt.) What Gavin didn’t discuss is how you get from the version below to the IPCC version.
Figure 2. Briffa 2000 Figure 5 An indication of growing season temperature changes across the whole of the northern boreal forest. The histogram indicates yearly averages of maximum ring density at nearly 400 sites around the globe, with the upper curve highlighting multidecadal temperature changes… The LFD curve indicates low-frequency density changes produced by processing the original data in a manner designed to preserve long-timescale temperature signals (Briffa et al., 1998c). Note the recent disparity in density and measured temperatures discussed in Briffa et al., 1998a, 1999b). Note that the right hand axis scale refers only to the high-frequency density data.
Gavin Schmidt stated that everything was “in plain sight”. Regular CA readers are used to watching the pea under the thimble. There is no mention in the IPCC report of the deletion of Briffa reconstruction data after 1960. Nor is there any mention of the deletion in the IPCC reference (Briffa 2000) nor, for that matter, in the article cited by Gavin Schmidt (Briffa et al 1998). These articles report the divergence, but do not delete it. (Briffa et al 2001 does delete the post-1960 values.)
Not only was the deletion of post-1960 values not reported by IPCC, as Gavin Schmidt implies, it is not all that easy to notice that the Briffa reconstruction ends around 1960. As the figure is drawn, the 1960 endpoint of the Briffa reconstruction is located underneath other series; even an attentive reader easily missed the fact that no values are shown after 1960. The decline is not “hidden in plain view”; it is “hidden” plain and simple.
Figure 3. Blowup of IPCC Figure 2-21.
Previous discussion of these issues is at Climate Audit here here here and more recently by Jean S here. Jean S and UC report at CA that the puzzling end point properties can be replicated by replacing actual proxy data after 1960 with instrumental data and then smoothing (truncating back to 1960) – exacerbating the problem. (I haven’t personally confirmed this, but Jean S and UC are extraordinarily skilled analysts and know this material as well as I do.) Jean S:
In order to smooth those time series one needs to “pad” the series beyond the end time, and no matter what method one uses, this leads to a smoothed graph pointing downwards in the end whereas the smoothed instrumental series is pointing upwards — a divergence. So Mann’s solution was to use the instrumental record for padding, which changes the smoothed series to point upwards as clearly seen in UC’s figure (violet original, green without “Mike’s Nature trick”).
Jean S then drolly quoted Mann:
No researchers in this field have ever, to our knowledge, “grafted the thermometer record onto” any reconstruction. It is somewhat disappointing to find this specious claim (which we usually find originating from industry-funded climate disinformation websites) appearing in this forum.
The Climategate Letters contain a very interesting discussion between Mann, Jones, Briffa, Karl and Folland worrying that showing the discrepancy would provide “fodder to the skeptics”. More on this tomorrow.
Lee
I didn’t mean to discount your idea. In fact I’m concerned that you may well be right, and that politics will win out over science. But I take heart in knowing that the AGW tanker seems to have hit an iceberg and is now listing badly to one side.
Those who wish to see an end to the AGW religion expect a speedy end to the political debate in light of the academic misconduct uncovered. I would caution you to think of the long game, which is death by a thousand cuts. Each democratic country that attends Copenhagen will eventually have to answer to the citizens who don’t believe in the AGW religion.
It is our job to increase the volume (both in numbers and voice) of the non-believers so that politicians who ignore them will find themselves considering an existence that does not include elected office.
The LFD curve indicates the world was warmer in the 1930’s than currently. There’s a lot of material that indicates the Arctic was very warm in the 1930’s. Is there any other evidence supporting the fact that the 1930’s may have been warmer than now ?
Quick quick
Thermometer’s sick
Hide the downtick
Span and spick
The Hockeystick Trick
@ur momisugly David S (11:09:47)
I know you weren’t discounting my thought David. We’ll see what the next few weeks bring.
Interesting times………
Go vote – & leave a comment !
http://www.sciencemuseum.org.uk/proveit.aspx
quote my comment :
the release of the CRU data into public domain indicates some very very serious problems with teh use of the scientific method.
How can anyone take any of the claims made by AGW seriously ?
As an absolute minimum a complete un-biased review of all the data and models used needs to be undertaken urgently.
Copenhagen should at the very least be postponed while independent scientists carry out this review
end quote
@peter_dtm, Copenhagen will proceed with or without the science, but Copenhagen is merely a way station. In the aftermath of the Copenhagen farce, the citizens of the U.S. will be our best hope to put an end to the fraud. Talk about hope and change!
this made me want to throw up:
http://www.rasmussenreports.com/public_content/political_commentary/commentary_by_froma_harrop/whom_can_you_trust_on_climate_change
In 1960 Edward Lorenz asked, “Does the Earth have a climate? The answer, at first glance obvious, improves on acquaintance.” About 1975 Benoit Mandelbrot expanded on Lorenz’s Chaos Theory –positing a “butterfly effect” with “strange attractors” etc.– by formulating Fractal Geometry, a depiction of natural reality as non-random but strictly indeterminate, self-similar on every scale. Together, Lorenz and Mandelbrot determined that extrapolating phenomena of suitably complex systems (those where three or more variables interact) is mathematically as well as physically impossible.
Earth’s atmosphere is such a “complex system”. Therefore analysis in detail, leading to meaningful forecasts or projections, is fundamentally impossible in principle. Climatologists adducing ambiguous historical data, necessarily incomplete and inconsistent, to plot not merely local but global temperatures decades in advance are either ignorant of mathematics, fools, or mendacious charlatans. On recent evidence, Briffa, Hansen, Jones, Mann et al. stand self-convicted on every count.
Since the Cretaceous/Tertiary (K/T) Boundary 65 million years-before-present (YBP), geological eras have averaged a highly variable 12 – 15 million years. At 1.8 million years to date, our current Pleistocene Era is no more than one-sixth past. This present period is characterized by regularly recurring ice ages averaging 102,000 years, interspersed with intermittent Interglacial Epochs of median 12,250-years duration. The latest glacial episode began about 116,400 YBP and ebbed from c. 14,400 YBP, set back 1,500 years by the Younger Dryas “cold shock”, a glacial rebound precipitated by a rain of cometary/meteorite debris impacting Earth from Sol’s enveloping Oort Cloud. On this basis, the present Holocene Interglacial Epoch was imprecisely due to end in AD 2000 + (12,250 – 12,300) = AD 1950.
As Lorenz suspected, atmosphere does not drive “climate change”. From 1964, geophysicists have known that plate tectonics, Alfred Wegener’s “continental drift” hypothesized in 1912, constantly reconfigures continental dispositions on geologic time-scales. Cyclical Pleistocene glaciations began when North and South America walled off Earth’s eastern and western hemispheres, blocking circulation of deep-ocean (bathymetric) currents, regularly resetting global thermostats. This phenomenon will only end 12 – 15 million years from now, when hemispheric landmasses shift sufficiently to re-establish oceanic circulation patterns.
There is no global warming, nevermind “anthropogenic” warming due to civilization’s emission of beneficent CO2. “Greenhouse gases” are in fact a myth: Basic physics, whereby evaporating hot air rises to draw cooler northern currents underneath, cites convection currents rather than any micro-pollutant as symptom, not cause, of long-term cyclical “climatic” shifts. Precipitation becomes key– flooding rains in summer, blizzard snows in winter. “Weather”, yes, but inextricably a part of Lorenz’s and Mandelbrot’s “complex system”, what in 1974 Dr. Lewis Thomas aptly called “Lives of a Cell”.
The idea that a tight-knit cabal of grossly self-interested ideologues could set themselves to purposefully destroy post-Enlightenment civilization, sabotage global energy economies, subvert Borlaug’s seminal Green Revolution, is an unbearable insult not only to our forebears but to that posterity for which we act as stewards. When it emerges that these same blighted psyches, Luddite sociopaths in league with singularly atavistic, regressive Statist demagogues, have violated not only ethical and legal norms but perverted the very cause of Science itself, indictment for Crimes Against Humanity should be the least result.
As of AD 2010, Sol seems poised to enter a 70-year “dead sun” phase known as a Maunder Minimum (the last such doldrums lasted from AD 1645 to 1715, when wolves froze to death in Rhineland forests and Louis XIV’s goblet glazed with ice in his Palace of Versailles).
A disturbing thing is Obama’s Energy “Czar” Carol “Brownshirt” Browner doesn’t care about anything but her radical agenda: http://bit.ly/513De4
How is it that we have “Czars” in America creating policies behind the scenes without Congressional oversight? These Czars are blatant Maoists, Leninists, and Marxists. I’ve heard these Czars declaring their admiration for Mao and that sometimes guns must be used to implement policies.
We must get rid of the “Czars.”
Oh the “Trick”………………..
I see that Gavin over at RC is spinning like crazy about the “Trick”.
If you have any wet clothes; just toss them on him and they will be dry in no time…………
Serenity now………..
I have refrained from weighing in on this since it began, since my time has been required elsewhere and what brief time I could allot has been spent trying vainly to catch up to the wave of developments and comments. With a little more time to review this morning I am struck by how everyone seems to be studiously avoiding the 800 pound gorilla in the room on this “mike’s trick” or “neat technique” situation. As I understand “the divergence problem”, when attempts have been made to reconstruct the paleo temperature record using tree ring proxies some, for reasons no one seems able to explain, fail miserably when trying to model the present temperature record, others supposedly do not.
To my mind there are only a couple of rational ways of dealing with such a development. The diverging reconstructions would either be sent immediately to the round file or, at a minimum, be set aside until a reasonable explanation of the divergence could be provided. Instead we have the application MM’s “trick” to conceal the proxy’s unreliability. BTW, given MM’s role as putative innovator of this “neat technique”, one has to wonder what role it has played in his own work over the years. From my, admittedly limited, reading of the discussion that is not altogether clear.
At any rate, the fact that they have consciously and consistently attempted to use these dubiously reliable divergent proxies as either primary or secondary data for their paleoclimate reconstructions alone provides a more ringing condemnation of their scientific standards than any discussion of the “trick” they used to accomplish it could hope to offer.
The IPCC mentions this with a specific disclaimer:
http://www.ipcc.ch/ipccreports/tar/wg1/504.htm
Is anyone aware of a paper or mathematical proof that shows the calculations involved in GCM’s inherently meet the definition of a chaotic system and cannot be predicted far into the future?
It would be nice to reference an authoritative paper that shows the assertion that long term climate can be predicted is inherently impossible according to current Chaos theory.
If none exists perhaps one of our statistical/mathematics contributors could sketch out such a logical attack on the AGW thesis that long term climate is predictable.
I understand that the AGW proponents will, probably respond that they do not make predictions, but run scenarios and draw conclusions from the results. My gut instinct is like, Dr. Richard Lindzen has said, doing the same faulty calculation multiple times and then averaging the results is not a method that has merit.
Larry
I did find this interesting history of GCM development while I was searching.
http://www.aip.org/history/climate/GCM.htm
Larry
If you think it’s all over check this site: http://www.globeinternational.org/content.php?id=1:1:0:0:0
The final G8 + 5 Climate Change Dialogue Legislators Forum was held in Tokyo, Japan in June 2008. One hundred senior legislators from across the G8 and +5 made a historic breakthrough agreement on Lord Michael Jay’s Post 2012 Framework Paper. This document, enjoying full consensus of all legislators, showed world leaders that agreement is possible on the core elements of a post 2012 agreement. The Agreement was a major statement ahead of the Hokkaido G8 Summit and was presented to Prime Minister Fukuda by the fifteen heads of the GLOBE G8 and +5 delegations on Monday 30th June. The agreement follows high level speeches to the GLOBE Tokyo Forum by Prime Minister Fukuda, US Presidential Candidates Senator John McCain and Senator Barak Obama, former UK Prime Minister Tony Blair and the former Japanese Prime Minister Shinzo Abe.
http://www.globeinternational.org/news.php
29/06/09
GLOBE Rome G8 +5 Legislators Forum Speeches
Keynotes speeches in Rome were delivered by Prime Minister Lars Løkke Rassmussen the Danish Prime Minister, President Fini, President of the Italian Chamber of Deputies, Stephen Byers MP, President of the Global Legislators Organisation (GLOBE), Congressman Wang Guangtao, Chairman of the National People’s Congress Standing Committee on Environment Protection & Resources Conservation, Congressman Edward Markey, Chairman of the US House Select Committee on Energy Independence and Global Warming and Chairman of the US House Energy and Environment Subcommittee, Deputy Jose Luis Espinosa Pina, Vice-President of the Mexican Chamber of Deputies, Senadora Serys Slhessarenko, Deputy President of the Senate of Brazil, Representative Takashi Kosugi, former Cabinet Minister for Education & Science and current Chairman of the LDP’s Environment Research Council.
They will push ahead regardless.
This stuff is based on just one more pseudoscientific fad, destined to be put away in the dusty attic of science. Piltdown Person, phlogiston, phrenology, spontaneous generation, Lysenkoism, geocentrism, medicinal leeches, Kirlian photography, astrology, spiritualism, dildoclimatology, and all the others.
Even with my very limited scientific knowledge I have been able — thanks to many good articles — to understand a lot of the email summaries and computer code notations, but one exception is this business about the “trick”. Even after reading this article and the comments, I still do not understand what the trick was. Can someone explain this in very simple terms? It sounds like they were having trouble coming up with a model that accurately reflected recent and current temperatures, yet would still give them the projections of unprecedented global warming that they wanted. Even if I’ve got that part right (and I probably don’t), I still don’t know what the “trick” was. Would someone please give me the “Climategate For Dummies” version? I’ll check back here tomorrow.
BTW, I’d never heard of Mr. McIntyre, CRU, or hockey stick charts until this week. It’s all very interesting, also depressing.
Josh
“A disturbing thing is Obama’s Energy “Czar” Carol “Brownshirt” Browner doesn’t care about anything but her radical agenda: http://bit.ly”
She was under court order not to destroy data as she left the EPA as director. The EPA was caught funneling money to non-profits for obvious political gain. She ordered all the hard drives be reformatted. Their is no way she was going to be appointed to something needing congressional approval. So now she is a bama CZAR
Peewit (07:38:58) “The effect of fully working low pass filtering is a massive reduction in the amplitude of fast data movement” and dfbaskwill (07:04:58)
I was blown away last week when I first learned about the Slutsky-Yule effect, when random numbers are subject to low pass filtering and produce a lovely, very believable, smooth gently oscillating line. Yes random numbers, I found this in a book ‘Climate Cycles, Real or Imaginary’, Steve Mc Intyre has mentioned this effect in 2008.
But this very real effect must, must, be removed from every chart before they can be further analysed.
Steve,
Thank you for this and all of your efforts!!
Much appreciated by all.
Stay the course.
Thanks,
Clive
Alberta
Lee (10:13:26) :
@David S
Mike Tyson was unbeatable too. Then Buster Douglas punched his mouthpiece out.
Lucy Skywalker (12:23:37) :
How the the Hockey Stick trick hold up under oath heated by Senate camera lights?
Brenda (18:01:58) :
If I have it right–the tree ring proxy data began to show a downward turn on the graph at 1960. But, they needed there to be a continued upward movement in the graph for their global warming theory to be right; they needed to “hide the decline” that began at 1960. So, at the 1960 point in the data they stopped using the tree ring proxy data. And in its place they took a different data set that showed upward movement at 1960, spiced it on to the tree ring data, and
Voilà! “Mike’s Nature trick”.
Two things need to be done at this point:
1. Perform forensic analysis on the CRU models that were just released and come to some conclusions. Were the models completely tainted by fraud or not? (I have a feeling I know what the answer will be) If the fraudulent data and formulaic work is backed out, what results do the models show? (assuming completely worthless, garbage in, garbage model, garbage out, but you have to check this out)
2. Analyze the number of studies that cited this work and those articles that cited the work that cited the fraudulent work and so on. Assuming the answer to #1 is fraud, they are all now suspect. This is one I can tackle or with the assistance of anyone with access to the “Scientific Citation Index”. It may be possible to knock out a whole swath of junk in one swoop.
We will publicize these results.
Speaking of good proxies for cooling, isn’t the location of the citrus line (the latitude above which citrus fruit can’t grow) a good one? As I recall the citrus line used to be as far north as Atlanta, but is now all the way down to about Orlando.