Understanding Climategate’s Hidden Decline
By Marc Sheppard The American Thinker
Close followers of the Climategate controversy know that much of the mêlée surrounds an email in which Climate Research Unit (CRU) chief Phil Jones wrote about using “Mike’s Nature Trick” (MNT) to “hide the decline.” And yet, 17 days and thousands of almost exclusively on-line op-eds into this scandal, it still seems very few understand exactly which “decline” was being hidden, what “trick” was used to do so, and why Jones’s words have become the slogan for the greatest scientific fraud in history.
As the mainstream media move from abject denial to dismissive whitewashing, CRU co-conspirators move to Copenhagen for tomorrow’s UN climate meeting, intent on changing the world as we know it based primarily on their now exposed trickery. Add yesterday’s announcement of a UN investigation into the matter, which will no doubt be no less corrupt than those being investigated, and public awareness of how and why that trick was performed is now more vital than ever.
So please allow me to explain in what I hope are easily digestible terms.
First and foremost — contrary to what you’ve likely read elsewhere in the blogosphere or heard from the few policymakers and pundits actually addressing the issue, it was not the temperature decline the planet has been experiencing since 1998 that Jones and friends conspired to hide. Certainly, the simple fact that the email was sent in November of 1999 should have allayed any such confusion.
In fact, the decline Jones so urgently sought to hide was not one of measured temperatures at all, but rather figures infinitely more important to climate alarmists – those determined by proxy reconstructions. As this scandal has attracted new readers to the subject, I ask climate savvy readers to indulge me while I briefly explain climate proxies, as they are an essential ingredient of this contemptible conspiracy.
Truth be told — even reasonably reliable instrumental readings are a relatively modern convenience, limiting CRU’s global measured temperature database to a start date somewhere in the mid-19th century. That’s why global temperature charts based on actual readings typically use a base year of 1850 or somewhere thereabouts.
And yet — most historical temperature charts, including the one Al Gore preached before in An Inconvenient Truth, go way back to 1000 AD. That’s where proxies come in.
While historical documents (e,g, ship’s logs, diaries, court and church records, tax rolls, and even classic literature) certainly provide a glimpse into past temperature trends, such information is far too limited and generalized to be of any statistical value. So climate scientists have devised means to measure variations in such ubiquitous materials as lake sediments, boreholes, ice cores, and tree rings to evaluate past temperature trends.
They then employ complex computer programs to combine such “proxy” data sampled throughout a region to plot that area’s annual relative changes in temperature hundreds or even thousands of years prior. By then combining the datasets, they believe they can accurately reproduce hemispheric and global temperature trends of the previous millennia.
And while reconstructions — as past temperature interpretations from proxy data are called — can differ greatly from one source to another, those generated by the CRU have often been accepted as the de facto temperatures of the past.
Largely because the UN’s Intergovernmental Panel on Climate Change (IPCC) proclaims them to be.
Warmist Public Enemy Number One: The Medieval Warming Period
It’s important to understand that early analyses of these “proxies” clearly demonstrated that three radical temperature shifts occurred within the past millennium, as do many contemporary studies. Indeed, the years 900-1300 AD were labeled the Medieval Warming Period (MWP), as global temperatures rose precipitously from the bitter cold of the previous Dark Ages to levels several degrees warmer than today. The Little Ice Age, a sudden period of cooling, then followed and lasted until the year 1850. And then began the modern warming period, which was by no means unique and appears to have ended with the millennium itself.
Originally, even the IPCC accepted that pre-20th century analysis. In fact, the 1990 First Assessment Report used this schematic IPCC 1990 Figure 7c (courtesy of Climate Audit) to represent last millennium’s dramatic temperature swings.

But this image of a fluid climate system subject to abrupt and natural up-and-downturns made unprecedented 20th century warming about as marketable as Florida swampland. And opportunists who depended on the aberrance of post-industrial revolution warming in order to condemn and control mankind’s CO2 emissions soon recognized that perhaps the LIA but most certainly the MWP simply had to go.
And as many of these hucksters were closely connected to the IPCC – both sender and recipient names on those illuminating CRU emails include many of its editors, lead authors and contributors — that task was far less daunting than one might imagine.
Proxies, Tricks and Hockey Sticks
The first step was taken in the 1995 Second Assessment Report, when the above Figure 7c was replaced with a 1993 reconstruction from RS Bradley and Phil Jones himself that used 1400 AD as its base – effectively wiping the MWP off the radar-screen.
But it wasn’t until the 2001 Third Assessment Report (TAR) that the MWP simply vanished. This multi-proxy reconstruction of Northern Hemisphere temperature anomalies appeared in chapter 2, page 134, of the Working Group 1 (WG1) report [PDF].

IPCC 2001 WG1 Fig 2.20
Of course, the first thing you’ll notice is that both the MWP and LIA have indeed disappeared. In fact, temperatures appear to trend downward throughout the millennium until a sharp jump upward last century. But if you look closer, you’ll also notice that the “reconstructed” series terminate in 1980. What forms the dramatic blade to the hockey stick shape (yes, this is indeed the famous “Hockey-Stick” graph) is instead the distal segment of the 1902 to 1999 instrumental data series.
Mann has recently claimed that the available proxy data ended in 1980, but even his coconspirators at RealClimate admit that’s nonsense. The truth is that the proxy data was scrapped because unlike those measured, reconstructed temperatures showed a marked decline after 1980. And, as the chart plotted temperature anomalies against what the plotters selected as the “normal” period and temperatures of 1961 to 1990, the reconstruction would have been quite unremarkable otherwise. So at the 1980 mark, the actual post-1980 measurements were actually attached to the truncated proxy series to create the illusion they were one.
The figure below, found on the same page of the WG1 report reveals this trick more clearly. This chart plots the original 4 reconstructions used: 2 from Mann et al, 1 from Jones et al and 1 from Briffa et al. Notice how all but the first series continue to trend downward around 1960 while instrumental readings begin to trend upward? And even that series ends abruptly in 1980.

IPCC 2001 WG1 Fig 2.21
So not only did conspirators cherry-pick the one series of the four that approximated measured temperatures the longest, they also terminated that series at the point that it too, began to trend down. They then joined it to the actual 1980-1999 temperatures to “hide the decline” in the final product, as that decline created an inexplicable divergence between the reconstructed and measured temperatures. The existence of which challenges the entire series dating back to 1000 AD.
Remember, all of the temperatures prior to 1850 were estimated by computer algorithms and no actual readings exist to prove or disprove those figures. So a relatively short window of opportunity exists to test the programs against observations. Had 20th century measured temperatures continued to align with those recreated as smoothly after 1960 as they did previously, then the programmers could declare their code and hence their millennial temperatures sound. But the divergence, if allowed to stand, instead revealed serious design flaws in the proxy reconstructions. Which suggests that just as the decline was dealt with through trickery, so was the MWP.
And it seems that each time the trick was used, its involvement would be more deeply concealed.
Every multi-volume IPCC Assessment has been accompanied by a relatively brief and highly-politicized Summary for Policymakers (SPM). This synopsis invariably commands the bulk of the media and political attention. Here’s the version of the graph depicted prominently on page 3 of the 2001 TAR SPM [PDF], the only version of the report most policymakers and reporters would ever actually see. Notice how they further obscured their chicanery by omitting the series defining legend and the “1988 instrumental value” declaration:

IPCC 2001 SPM Fig 1b
And despite the fact that the only confirmable segment of the series failed that very test, which should have declared the entire series null and void, the chart’s caption informed policymakers that:
“the rate and duration of warming of the 20th century has been much greater than in any of the previous nine centuries. Similarly, it is likely that the 1990s have been the warmest decade and 1998 the warmest year of the millennium.”
And it’s this highly fraudulent version that has become the poster child of the equally fraudulent Anthropogenic Global Warming (AGW) movement.
Thanks in large part to the trick that hides the decline.
Trick or Cheat
Now we’ll take a closer look at exactly what Jones meant when he wrote that he had “just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline.”
Why did Jones refer to the ruse as “Mike’s Nature Trick?”
As die-hard Hockey Team opponents and fans alike already know – the original 600-year version of the now infamous “Hockey-Stick” graph was dubbed MBH98 because it first appeared in the Michael Mann, Raymond Bradley and Malcolm Hughes paper Global-Scale Temperature Patterns and Climate Forcing Over the Past Six Centuries [PDF], originally published in the science journal Nature in 1998. And “Mike’s Nature Trick” received its dubious designation among CRU insiders for the very same reason.
As to the rest of the sentence — It seems Jones was working on a cover chart for a forthcoming World Meteorological Organization report [PDF], WMO Statement on the Status of the Global Climate in 1999, when he wrote the email. As the graph would incorporate one reconstruction of his own plus one each from Michael Mann and Keith Briffa, he was informing them that he had used the trick on Mann’s series at the same 1980 cutoff as MBH98, but found it necessary to use 1960 as the cutoff on the Briffa series.
And what I uncovered in the source code told the tale why. While Mann used multiple proxy sources, Briffa’s reconstructions were based solely on a property of annual tree ring growth known as maximum latewood density (MXD). And the MXD-only-driven plots began to diverge from actual temperatures as early as 1960. In fact, while many of CRU’s programs are designed to exclude all data after 1960 for later manual splicing with instrumental data, others employ “fudge factors” to force the generated plot to more closely adhere to measured temperatures as far back as 1930.
And as you’ll soon see, Jones’s admitted use of MNT took it to an entirely new level of fraud.
Here’s the original reconstruction, with the three proxy and measured temperature (black) series intact:
Notice how Briffa’s series (green) begins to trend sharply downward around the mid-20th Century. Jones’s series (red) soon follows but less sharply and then begins to trend higher. Mann’s (blue) appears to flatten out around the same year that Jones’s begins to fall. Meanwhile, all three have broken with the measured rising temperatures of the late 20th Century.
Now take a look at the chart actually published by the WMO, with all three proxy series having been surreptitiously subjected to MNT:

Since the release of CRU’s FOI2009, alarmists have continued their claim that there’s nothing deceptive about the “trick” and that it has been openly discussed in scientific journals like Nature since 1998.
But I defy anyone to compare the above chart – the one Jones wrote he had applied MNT to – to the unadulterated version above it, and tell me there’s been no deception committed. At least with MBH98, a sharp eye might recognize the ruse. Here — there is no indication given whatsoever that the graph represents an amalgam of proxy and measured temperatures. This, my friends, is fraud.
And I hope that those investigating the fraud will carefully consider this explanation of his WMO cheating given last week by Jones: [my emphasis]
“One of the three temperature reconstructions was based entirely on a particular set of tree-ring data that shows a strong correlation with temperature from the 19th century through to the mid-20th century, but does not show a realistic trend of temperature after 1960. This is well known and is called the ‘decline’ or ‘divergence’. The use of the term ‘hiding the decline’ was in an email written in haste. CRU has not sought to hide the decline. Indeed, CRU has published a number of articles that both illustrate, and discuss the implications of, this recent tree-ring decline, including the article that is listed in the legend of the WMO Statement figure. It is because of this trend in these tree-ring data that we know does not represent temperature change that I only show this series up to 1960 in the WMO Statement.”
And they’ll immediately recognize the dishonest denial they’re dealing with when they read the WMO Statement figure from the inside cover Jones referred to:
“Northern Hemisphere temperatures were reconstructed for the past 1000 years (up to 1999) using palaeoclimatic records (tree rings, corals, ice cores, lake sediments, etc.), along with historical and long instrumental records. The data are shown as 50-year smoothed differences from the 1961–1990 normal. Uncertainties are greater in the early part of the millennium (see page 4 for further information). For more details, readers are referred to the PAGES newsletter (Vol. 7, No. 1: March 1999, also available at http://www.pages.unibe.ch) and the National Geophysical Data Center (http://www.ngdc.noaa.gov).”
Even if MNT had been explained as Jones claimed — which it wasn’t — just how was the observer expected to differentiate the reconstructed from the actual data? And good luck finding that newsletter.
Spin it anyway you want – Mike’s Nature Trick is Phil’s WMO cheat.
More Tricks of the Charade
While suddenly the most famous, Mike’s is not the only in CRU’s bag of tricks.
Many of the programs I reviewed contained routines to exclude proxy data that demonstrated poor correlations with local temperature, which of course explains why CRU’s 19th through mid-20th century proxy temperatures appeared to be observationally accurate. Others “estimated” values for missing data.
And then there’s the Yamal matter – also a popular subject of the CRU emails.
In an October 5th email to climatologist Tom Wigley, Jones took issue with a piece I had written that day exposing the lies in CRU-based UN climate reports, which included a section on Keith Briffa’s mistreatment of Polar Ural data in order to exaggerate 20th century warming. That email prompted the reply from Wigley — now familiar to AT readers — in which he admitted it was “distressing to read that American Stinker item,” before offering to help Briffa, who “does seem to have got himself into a mess,” write an “explanation” for his deceitful cherry-picking of Yamal peninsula data.
Indeed, Keith’s Yamal Trick also “fudged” proxy reconstructions, not by overwriting them with instrumental data ala Mike, but rather by underhandedly stacking the actual dataset with trees hand-picked to assure his predetermined outcome. Yet both methods intentionally corrupted reconstruction results for the same devious purpose — to skew late 20th century temperatures higher in order to artificially create the dreaded hockey stick effect.
Now, you might be wondering why all this fuss is being made over late 20th century temperatures when even we realists accept that they did rise until 1998. Hopefully, you now understand why the divergence between proxy and measured temperatures betrays a potential serious flaw in the process by which temperatures are reconstructed from tree-ring density. And that any reconstruction demonstrating such a flaw-revealing divergence should be dismissed outright, not presented as policy fodder.
But there’s another issue at stake here.
Anthony Watts has surveyed over 75% of the 1200-plus U.S weather stations from which national temperatures are accumulated. Most of those were found to be inaccurate by more than 2°C, largely due to being located within 10 meters of an artificial heating source. In fact, less than 10% met strict placement guidelines set forth by the National Oceanic and Atmospheric Administration. Not to worry — NOAA claims it has methods to “adjust” for such bias, including the use of “smoothing” adjustments to “homogenize” station data to that of surrounding stations.
Unpublished computer programs artificially adjusting the data — what could possibly go wrong with that?
Would you be shocked to learn that at ICCC 3, Watts told us he had calculated such adjustments to raw temperature data between 1940 and 1999 to be 0.5°F to the positive? That accounts for almost one half of the 1.2°F warming over the last century.
And that’s here in America. Try to imagine what kind of shenanigans might be going on elsewhere in the world.
Consequently, even the “instrumental” temperatures the CRU crooks were fudging their results to align with were likely themselves fudged. So they were pumping the incline while hiding the decline.
Hold the Fudge and the MWP won’t budge
In a June 2003 email to Jones and company, Mann discussed the notion of expanding CRU charts to 2 millennia, in an effort to ‘try to “contain” the putative “MWP.”’ No deception in that, I suppose. Of course, an honest 2000 year reconstruction, such as this one from CO2Science.org, adapted from a 2005 Moberg et al. temperature history derived from tree-rings and lake and ocean sediments, would actually emphasize rather than “contain” the MWP:

Any questions why Mann and friends work so diligently to “contain” (hide) the MWP?
As you can see, the post-LIA warming that began around 1850 is neither unprecedented nor spectacular. And certainly not worth rewiring the economic circuitry of the planet over.
And the CRU/IPCC reconstructions have been counterfeited for the express purpose of hiding that very fact.
After all, the stakes are enormous – perhaps trillions of dollars and unquestionably every American’s personal liberties. Tomorrow, over 20,000 delegates from 193 nations will gather in Copenhagen to craft an agreement which would not only force American power consumption to levels equal to those of about 1910, but would also have us pay reparations for an imaginary “climate debt” we’ve accumulated by building the world’s greatest economy of all time. That debt is based on the amount of CO2 our financial growth has purportedly pumped into the atmosphere, which, according to the conclusions of the IPCC, based largely upon reports from the CRU, has selfishly imperiled the planet by inducing climate change.
Of course, asking Americans to pay reparations based on the claim they’ve done harm to other nations by spoiling the climate is like asking me to pay damages to my neighbor based on his claim that he can’t sell his house because my great-grandmother’s ghost is haunting it.
As many have known and Climategate has proven, either would be equally preposterous.
But at least belief in ghosts is only marginally inspired by fraud.

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A very good, clear and concise summary!
And good luck finding that newsletter.
It’s listed here and in PDF here. Doesn’t seem to be the most prestigious of publications, but who am I to judge?
Hello,
I dont understand how you can combine proxy and real temperature data on the same graph? Isn’t it what in English called ‘compare apples to oranges’?
PS. English ios not my first language.
When life started 4 billion years ago I thought the atmosphere was 30% carbon dioxide and 30% methane. Methane is often quoted as being 30 times worse than CO2 as a greenhouse gas, which would mean that there would be [in effect] over 30,000 times more greenhouse gas than there is today. The oxygen producing bacteria that make stromatolites live on the seashore, and they are not extremophiles so the Earth’s climate at that time can not have been far removed from today.
This would be my test for any climate model, to plug in the values for Earth’s early atmosphere and get a result which we know must have been conducive to life. I suspect the current climate models have in-built ‘biases’ to promote the idea that trace amounts of CO2 control the Earth’s climate totally, and putting in these high values of CO2 and methane would have the climate models suggest the Earth’s surface would be hot enough to boil lead!
Hmm. The unprecedented melting of the ice caps must be a figment of my imagination.
There’s clearly some amount of risk hat man-made climate change will do serious harm. Even if you think there’s an 80% chance that the climate models and real-world measurement are wrong, it seems ludicrous to gamble your progeny’s future on a on that bet. If you had a 1 in 5 five chance of dying the next time you got in your car, would you still do it? The stakes are enormous if the models and measures prove to be right, yet people are perfectly willing to take that gamble. Amazing.
All of this is an eerie reminder how easily people will disregard evidence, ignore risks, and believe what they want to believe. It happens in every economic speculative bubble. Now it’s happening with climate change. Let the good times roll!
The World Meteorological Organization (WMO) on Thu Aug 21, 2008 reported: “The first half of 2008 was the coolest for at least five years, the World Meteorological Organisation (WMO) said on Wednesday. The whole year will almost certainly be cooler than recent years, although temperatures remain above the historical average.”
Yet on 5 December 2009 they reported at the Copenhagen Summit: “This decade is the warmest on record and 2009 is likely to rank as the fifth warmest year since the beginning of instrumental climate recordings in 1850.”
Vicky Pope, head of climate change advice at the Met Office, said the Office analysed land temperature data using a computer code developed by CRU. She said CRU also supplied the Met Office with original data from some remote weather stations which had a significant impact on the global average.
This sudden backflip for the IPCC and Copenhagen Summit is making many wonder if the WMO are the latest to have adopted Michael Mann’s “trick” of massaging data to suit a preconceived agenda!
Cheers,
Denis Maclaine
Brisbane, Australia
The IPCC 1990 Figure 7c diagram is linked to the old site, which is now a dead address:
http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg
The correct (working) link is:
http://climateaudit.files.wordpress.com/2008/05/lambh23.jpg
Note that the link exists in two places in the article: one as a clickable link, and the other as an embedded image.
Dave
OKE E DOKE, here’s the gist of it.
This article makes the point that the infamous “hide the decline” remark was about a huge problem with the AGW alarmists’ methodology for teasing temperature information from “proxies,” like tree rings. The problem is that the proxy info indicated that temperatures had been declining during the last 1/5 of the 20th century, when most other data (especially including ground station measurements) showed that temperatures were rising significantly.
That means their methodology for deducing temperatures from proxies DOES NOT WORK. It has been falsified by actual temperature measurements in the 1980s and 1990s.
That is critically important, because that temperature-from-proxy methodology is the ENTIRE basis for the now-infamous “hockey stick” graph. It was the SOLE basis for erasing the Medieval Warm Period from history.
The truth, as revealed by these emails, is that the IPCC’s leading climatologists were LYING. They were telling the world that there was no doubt whatsoever that late 20th century warming was unprecedented in history, because of the assured reliability of their proxy-derived temperature reconstructions, and that anyone who disagreed was a “denier,” implicitly akin in disreputableness to Holocaust Deniers. But the truth is that they KNEW full well that their methodology for deducing temperatures from proxies was unreliable, and they struggled mightily to “hide” that inconvenient truth.
This scandal is HUGE. It may eclipse Piltdown Man as the worst scientific scandal in history.
The leading climate research institutions & they key players in the IPCC (Mann, Jones, Hansen, Briffa, Kelly, Schmidt, Overpeck, Santer, Wigley, Osborn, Trenberth, Karl) etc., are ALL up to their eyebrows in this. The field of climate change research is a cesspool of intellectual dishonesty.
Their models don’t work. The models have been falsified by the temperature record, yet the so-called “leading” climate researchers doggedly stick by them. Defending the ideology & political agenda to which they are wedded has become more important to them than telling the Truth.
These guys have abandoned the scientific method!
You probably know how the Method is supposed to work:
1. The scientist observes the available data.
2. He formulates hypotheses to explain the observations.
3. He derives testable predictions from the hypotheses.
4. He devises tests or observations to test the testable predictions.
5. He does the tests or makes the observations.
6. If the test results match the predictions, he cries “eureka!” and publishes his theory.
7. If the test results fail to match the predictions, the theory is said to be “falsified,” so he discards or revises it and starts over at step 2, with the new observations or test results added to the body of available data.
Instead of discarding or revising their falsified models, these so-called scientists revise the data!!!!
And then they delete the original, raw data, so that nobody else can check their work.
That is the WORST kind of scientific dishonesty.
W/r/t the deleted data, I cite two documents to prove my accusation:
1. The first was email document 1107454306 from Jones to Mann. Jones says that if McIntyre requests the station data under the Freedom Of Information Act, he (Jones) will delete it rather than let McIntyre see it:
http://www.burtonsys.com/FOIA/1107454306.txt
Note that to do that without getting in trouble with the law they would have to lie and claim it had been deleted earlier… a prospect which apparently does not trouble them at all.
2. This Sunday Times (of London) article about the declaration from UAE CRU that they cannot comply with legal demands for the raw temperature data because they have deleted much of it:
http://www.timesonline.co.uk/tol/news/environment/article6936328.ece
And, whaddya know, they say it was deleted long ago (though they’d previously given a variety of other excuses for refusing FOI requests for the same data).
The bottom line is that these guys have proven themselves to be utterly untrustworthy. You can’t believe anything they say. (See Luke 16:10)
They’ve been claiming, stridently, that the earth is still warming. But if you read the leaked emails, you will see that even they know that isn’t so. They may expect the warming to resume, or they may doubt their measurements, but they KNOW that the temperature measurements indicate that the warming has ceased.
The earth ceased warming at least a decade ago.
Of all the actual temperature records (as opposed to so-called “proxies,” which are far less reliable), the records which showed the MOST warming were the surface station measurements, the most complete record of which are from the USA, where we’ve been making such measurements since 1880.
Argo buoys (deep ocean temperature measurements), radiosonde (atmospheric temperature measurements), sea surface temperature measurements, and satellite-based measurements ALL failed to show much if any warming (or at least they failed to show warming until the people discredited by this scandal “corrected” the data). But, we were told, the surface station measurements nevertheless proved the warming.
But now we know of widespread problems with the surface stations, which cause them to significantly overstate warming (see http://www.surfacestations.org). And then McIntyre discovered a major blunder by NASA, which had caused them to misreport 21st century surface station temperatures as warmer than they actually were. (And he found it despite the inexcusable fact that NASA/Hansen wouldn’t allow him access to the raw data!!!)
When NASA corrected that error 2.5 years ago, it made 1934 the warmest year on record.
That’s right. Not 2008. Not 2007. Not even 1998. 1934!
Still-unexplained “corrections” subsequently made by NASA/Hansen on the U.S. surface station data have bumped 1934 back down to 3rd-warmest. The surface station data for the USA keeps getting revised in suspicious ways by Hansen & Co. at NASA. Yet, even if their latest numbers are correct (which is highly doubtful), it still shows that 5 of the 6 warmest (we used to say “mildest”) years on record since 1880 were more than a decade ago, and 3 of the 6 warmest were 75+ years ago!!!
Facts like that kind of make the current warming hysteria seem silly, don’t they?
For the rest of the world, the surface station data was in the tender care of Phil Jones & the UEA CRU — where they have conveniently “lost” much of the raw data:
http://www.timesonline.co.uk/tol/news/environment/article6936328.ece
The bottom line is that the overwhelming weight of the evidence indicates that:
1) The leading climate change alarmists are utterly untrustworthy. And,
2) In the last quarter of the 20th century the earth was, indeed, warming, though not as much as the alarmists would have you believe. However,
3) Temperatures peaked in about 1998, plateaued, and then began declining.
4) The “settled science” nonsense predicting accelerating warming is totally discredited.
Those are the FACTS.
(Facts #3 & #4 should be cause for rejoicing, BTW, if you care more about the welfare of mankind and her planet than you do about being right!)
Now, there are many possible explanations for fact #3 (the end of warming a decade ago). NONE of them change the fact that the IPCC/alarmist models have been falsified. But there are still plausible scenarios for resumed warming, and continued concern.
One possibility is that the models greatly underestimated the effects of the sun, and the current unexpectedly long lull in the solar cycle has caused a cooling effect that is masking an underlying warming trend. If that is the case, then the warming should resume when the solar cycle resumes. If that happens, then we’ll need to grapple with the warming issue once again.
Another possibility for which there is evidence is that the models grossly underestimated the effects of CFCs. CFC levels are now declining, which could be the cause of the temperature decline. If that is the case, then warming will not resume when the solar cycle resumes.
Or it could be a combination of both of those causes, and/or some others.
But, regardless of what happens, the Kyoto/Copenhagen/Cap-and-tax schemes can’t possibly be a solution. Even if additional CO2 is actually causing warming (which is doubtful), there is NO possibility that these schemes could do more than slightly delay the effects.
Even Hansen realizes that. He’s a true believer in CO2 as the main AGW villain (I think he’s dead wrong), but he recognizes that the slight CO2 reductions achievable by these schemes can’t solve the problem. He says the Copenhagen approach is “fundamentally wrong,” and hopes the talks collapse.
Like a stopped clock, even James Hansen is accidentally right once in a while.
Complaints concerning the statement “hiding the decline” are without sense or foundation. The decline referred to is the divergence between tree-ring data and that of the instrumental temperature record since about 1960. Before 1960 the temperature records derived from a) tree -rings and b) instrumental sources (eg. thermometers – as shown in the HADCRUT3 series started in 1850) agreed well with one another. But since 1960 that is no longer the case: since then the measured trees have been growing more slowly than would be expected. Thus, using these trees as temperature proxies would give the impression that there was a decline in temperature since 1960 compared to what actually happened. There has been a lot of discussion in the scientific literature about this puzzling fact: it may be caused by pollution, disease, damaging UV because of reduced stratospheric ozone or something else. But, whatever the cause, it means that tree-ring data can no longer, since 1960, be used as a reliable temperature proxy.
Hence, when attempting to produce a graph of temperature for the last, say, 1000 years, there is a problem. For most of that time only proxies (eg tree-rings) are available: but for the last few decades such tree-rings are not reliable. The “trick” consists of joining the two sources of information (proxies and instrumental) together so that the recent “decline”, (as the recent tree-ring anomaly is called), can be substituted by the instrumental data.
Rather than being a source of confusion and denial concerning temperature reconstructions, the evidence for the “decline” should rather prompt questions as to the health of trees and concern about what the evidence of their slower rate of growth is telling us about the general health of our environment.
If you wish to see another clear explanation of this (and other email hack issues), I recommend:
The second picture linked to http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg is a broken link. What is the new link?
John M Reynolds
The old link for IPCC 1990 Figure 7c, showing the Medieval Warm Period, was http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg
The new (working) link is http://climateaudit.files.wordpress.com/2008/05/lambh23.jpg
Or you can view the article (with fixed link) at its original location:
http://www.americanthinker.com/2009/12/understanding_climategates_hid.html
Slioch, did you even bother to read Marc Sheppard’s article? He explained the chicanery very well.
The reason the earlier temperature measurements are fairly well-correlated with the proxy-derived temperature reconstructions is that those earlier temperatures are the temperatures which were used to calibrate the methodology. They HAD to match!
The problem is that the temperatures “reconstructed” by the methodology don’t match reality for OTHER time periods, such as the 1980s & 1990s, but also the Medieval Warm Period.
It means the method doesn’t work.
Sometimes that happens. A researcher has what seems like a great idea, but it just doesn’t pan out. What that happens, he is supposed to Man Up and admit the truth. Integrity requires it. In the conclusion of my own master’s thesis, I wrote, “We concluded that, for most applications, [our method] does not work very well…” Unfortunately, Jones, Mann, Briffa, et al, were unwilling to do that.
Dave Burton (09:23:41) :
Of course the tree-ring data were calibrated against the instrumental record, but it does not follow from that that they HAD to match: rather, in order for tree-rings to be used at all as a temperature proxy, they HAD to correlate, at least within acceptable limits of error. If it had been found that there was little or no correlation between the tree-rings and temperature then the method would never have got off the ground at all. It did get off the ground because they did correlate.
The most useful question to address now is “why has that correlation broken down after 1960?”. I confess I haven’t looked into the putative answers to that question in detail (I intend to), but I suggest that the answer may lie in a) increased tree diseases – there are numerous fungal tree diseases and insect pest that were formerly restricted in range that have been spread around the world by human activities, and b) atmospheric effects due to such factors as acid rain and black carbon or sulphate aerosols or low level ozone or other anthropogenic pollution.
But all that is something of a distraction from the main point of this post: the meaning of the “hide the decline” phrase. That phrase was used between individuals very familiar with the tree-ring data as acknowledgement that the post-1960 tree ring data was unreliable and needed to be replaced with the instrumental. To make out that it was evidence of fraud is scurrilous nonsense which will come back to haunt climate sceptics as people desperate to grasp at any straw, however absurd.
There is no reason to believe that the post-1960 tree ring temperature reconstructions are any less reliable than the pre-1880 tree ring temperature reconstructions, and especially the 900-1300 AD temperature reconstructions.
Indeed, the paucity of data for the more ancient dates makes those temperature reconstructions even WEAKER than the post-1960 temperature reconstructions.
BTW, have you noticed that the AGW alarmists’ sea level stats are wrong, too?
Last night I saw James Hansen on Letterman repeating (among other dubious claims) the statistic that the oceans have been rising 1.8mm/year for the past century or so. So I went to noaa.gov and downloaded their table of Mean Sea Level (MSL) changes for 159 locations around the globe.
The amounts of sea level change varied drastically, from one location to another. The greatest change was a 3 foot decline in MSL for Vaasa, Finland. The greatest increase in MSL was a 2.1 foot rise in MSL for Galveston, TX.
So I calculated two types of averages for the data, and the median.
Guess what? Neither the median nor the averages were anywhere near the claimed 1.8mm/year.
The median was just 1.1mm/year, or 39% lower than the claimed 1.8mm/year.
The averages were even lower, at 0.5-0.6mm/year, or only about 1/3 of the claimed 1.8mm/year.
Considering all the other chicanery from those folks, I can’t say that I’m much surprised.
I put up a web page with the results, here:
http://tinyurl.com/MSLavg
Dave
Siloch,
So If I understand you correctly you are guessing that tree-ring proxies are valid thermometer and temperature mismatch after 1960s is actually man-made which means that all of the data before 1960 is good? That is very interesting supposition. Actually it’s quite perfect. Not only we responsible for screwing up weather, we also managed to screw up indicators of our screw ups. Oh the evil of man!
On slightly more serious note, has there been any attempts made to validate this assertion? It shouldn’t be that hard to find some remote areas that are not subject to man’s influences. (Oh wait, that is probably why Briffa had picked his single tree in Siberia. It’s just strange that all the other trees located few tens of kilometers away didn’t quite do it for him)
SLIOCH,
I THOT THAT CO2 LEVELS HAVE INCREASED DRAMATICALLY SINCE 1960..
I ALSO THOT THAT TREE GROWTH RATES WERE GENERALLY INCREASED DURING
THIS PERIOD BECAUSE OF THE CO2 INCREASE
WHAT IS WRONG WITH YOUR TREES ??
The first diagram has disappeared.
Laura,
The new/correct/working link for the first diagram (IPCC 1990 Figure 7c, showing the Medieval Warm Period) is http://climateaudit.files.wordpress.com/2008/05/lambh23.jpg
The old/broken link was http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg
Or you can view the article (with fixed link) at its original location, here:
http://www.americanthinker.com/2009/12/understanding_climategates_hid.html
I tried to email Anthony Watts to tell him, but I might not have the right email address.
Dave
Thanks Dave.
Could someone please help me with this response from an obvious warmist. The response was made on a board many frequent from a well known commercial buying and selling site – not being scientifically minded myself, could I ask for your assisatance please? Many thanx.
——————————————————————————–
The Watts Up With That article
Quote:Add yesterday’s announcement of a UN investigation into the matter, which will no doubt be no less corrupt than those being investigated
No doubt the article would be calling for such an investigation if they had not announced it. Damned if they do, damned if they don’t.
Quote:it was not the temperature decline the planet has been experiencing since 1998 that Jones and friends conspired to hide. Certainly, the simple fact that the email was sent in November of 1999 should have allayed any such confusion
No it is NOT because there has not been a decline since 1998. 8 of the 10 warmest years on record have occurred since then, including 2005* which is the warmest year on record.
*If you ever read an article written in the last 4 years that says 1998 is the warmest year on record you know it is a fraud – they are using the unofficial GISS scale not the official US government NOAA scale so they can make the claim that temperatures have fallen since 1998.
There then follows a long discussion of the hockey stick that is full of half truths and sciency sounding statement but ar misleading. For example ….
Quote:Here’s the original reconstruction, with the three proxy and measured temperature (black) series intact:
They then make a big deal about how some of the reconstruction end in a downward trend but subsequently show an upward trend. Saying:
Quote:But I defy anyone to compare the above chart – the one Jones wrote he had applied MNT to – to the unadulterated version above it, and tell me there’s been no deception committed.
The red plot is the same between the two. The green plot still has the dip but in the first chart ended in 1950, in the second chart had been updated to end in 2000.
Hello! The main warming has occurred since 1970 so of course the plots will go up if you include that data. Same for the blue.
The author states that tree rings are just one of the proxies used for temperature reconstructions, the rest of the article makes it sound like it is the only one.
Why do tree ring data start becoming unreliable in the second half of the 20th century? The technique uses nuclear isotopes – so what have we been doing since then that might affect the trees – it would nothing to do with letting off atomic bombs and the building of lots of nuclear power stations? No, of course not – much more reasonable to believe there is a world wide conspiracy of scientists to implement political policies that for the most part they do not care about.
PS I note in this “learned” discussion that he ignores totally the gray areas around the Mann plots, That is the uncertainties and the plots of the medieval warm period fits neatly in that gray envelope. The reason? Is that you get the warm period if and only if you use only the western European and eastern US data. Thats how you determine the stability of your reconstruction by omitting various sub sets of data so the M&M medeval warm period result result is a cherry picked subset of the Mann data.
PPS I also note that if you take Moberg plot – Mann’s contention still holds this is the fastest rise seen in 2000 years. The appearance of the medeval warm period is slow – it takes 400 years to reach a peak. The current warming has taken just 100 years, some argue 40 years.
PPPS Note the Moberg plot also omits the latest 30 years of data when the most extreme increases in global temperatures have occurred so you can add another 0.5C to the end of his plot which would take it off scale.
I wonder why they forgot to mention that?
It must be a global conspiracy to falsify the data (or deliberately distoort it).
But who would have anything to gain by doing that? (Hint it rhyms with soil, lass, and foal)
First of all, that snarky warmist has no clue what he’s talking about. He’s just glowing smoke. E.g., this objection is pure nonsense:
“Why do tree ring data start becoming unreliable in the second half of the 20th century? The technique uses nuclear isotopes – so what have we been doing since then that might affect the trees – it would nothing to do with letting off atomic bombs and the building of lots of nuclear power stations? No, of course not – much more reasonable to believe there is a world wide conspiracy of scientists to implement political policies that for the most part they do not care about.”
Wrong. Tree ring-based temperature reconstructions do NOT use nuclear isotopes, they use tree ring density/width measurements.
Second, while it is true that Hansen’s NASA/GISS data is suspect, it is actually suspect for OVERSTATING warming, not understating it. Yet here’s what NASA was saying for U.S. “lower 48” temperatures two years ago, in September of 2007:
http://web.archive.org/web/20070914231348/http://data.giss.nasa.gov/gistemp/graphs/Fig.D.txt
The six mildest years on record (since 1880) in the lower-48 states of the continental USA were listed as:
#1: 1934
#2: 1998
#3: 1921
#4: 2006
#5: 1931
#6: 1999
Note that 1934 (not 1998 or 2005 or 2006) was listed as the warmest year on record, and 3 of the 6 were 75+ years ago.
NASA/Hansen have since revised the data several times (they won’t say how or why!), so that 1934 has been bumped from #1 position on the list. But those six are still the six warmest years listed even in the current version of their list, and 3 of the 6 warmest were 75+ years ago.
(I chose “six warmest” rather than 5 or 10 warmest, because it happens that the same 6 years are listed as warmest in all the versions of the NASA GISS file that I could find on archive.org, though in varying order; if you use 5 or 10 then some years drop off the list in some versions of the file.)
Note that this is based on U.S. surface station measurements, which are biased toward warming due to siting issues, urban encroachment, and probably institutional bias (Hansen!). Satellite, radiosonde & Argo buoy (deep ocean) measurements show even less evidence of warming.
Note: The U.S. surface station network is the best and longest-running in the world, outside of England. England’s heavily Gulf Stream-influenced island climate makes it a poor proxy for the world as a whole, unlike the U.S.
Note that even global sea level rise statistics seem to have been fudged by the AGW alarmists. They’ve been claiming a global average mean sea level increase of 1.8 mm/year, but it is really only about 1/3 of that, and many locations have seen sea level decreasese instead of increases:
http://tinyurl.com/MSLavg
Dave
http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg
The photo’s not there anymore (or here in this article).
Bonnie,
The new/correct/working link for the first diagram (IPCC 1990 Figure 7c, showing the Medieval Warm Period) is http://climateaudit.files.wordpress.com/2008/05/lambh23.jpg
The old/broken link was http://www.climateaudit.org/wp-content/uploads/2008/05/lambh23.jpg
Or you can view the article (with fixed link) at its original location, here:
http://www.americanthinker.com/2009/12/understanding_climategates_hid.html
I tried to email Anthony Watts to tell him, but I might not have the right email address.
Dave
I may be paranoid, having had a Christian upbringing but here goes. I have a gut feeling there is a small group of very influential people plotting control of the worlds populations. They can do it by controlling resources including food, economically, or by law enforcement. Using climate-change has back-fired on THEM hugely, even to the point of waking the apathetic. Could it be that all of the political push to get Darwins Theory TOTALLY accepted and Christians painted as mentally unstable have a parallel with this? I feel pressured to stop eating meat and stop thinking of myself as created in the image of God, instead I should become like the eugenics who believe each human life is not sacred but that even animals have the same status and rights as myself. Next stop a mark on my forehead?
this article say just what the average american wants to hear: we are not guilt of anything, these foreign suckers are just jealous of our mighty… let’s keep eating our cheese-burgers, driving our SUVs and drinking our beer until our belly explodes, fuck them, we are smarter!
these graphs and numbers are nonsense, they can be twisted the way you want. they can tell us the world is warming, coolling, static, changing, or whatever your agenda wants them to say. I’m not advocating GW here, I’m saying both sides can use these numbers to say whatever they want.
but this whole argument misses the point that we are indeed pillaging this planet at an alarming rate. at the current speed that we build more and more metropolis, empty the oceans and ruin the natural balance of the world with inconceivable amounts of garbage and pollution… who cares about weather change? we are going to transform Earth in a wasteland either way
in case anybody is looking for it,
I found PAGES Newsletter, Vol. 7 Nº 1 (The “hide the decline” reference in WMO 913) here
http://www.pages.unibe.ch/cgi-bin/WebObjects/products.woa/wa/product?id=81
Not a word about divergence, no mention (AFAIK) of the three WMO spaghetti studies, an obituary on Hans Oescher and extremely interesting tornetrask and taymir chronologies on page 6!
WMO 913: http://www.wmo.ch/pages/prog/wcp/wcdmp/statemnt/wmo913.pdf