What Do We Really Know About Climate Change?

A Guest Post by Basil Copeland

Like many of Anthony’s readers here on WUWT, I’ve been riveted by all the revelations and ongoing discussion and analysis of the CRUtape Letters™ (with appropriate props to WUWT’s “ctm”). It might be hard to imagine that anyone could add to what has already been said, but I am going to try. It might also come as a surprise, to those who reckon me for a skeptic, that I do not think that anything was revealed that suggests that the global temperature data set maintained by CRU was irreparably damaged by these revelations. We’ve known all along that the data may be biased by poor siting issues, handling of station dropout, or inadequate treatment of UHI effects. But nothing was revealed that suggests that the global temperature data sets are completely bogus, or unreliable.

I will return to the figure at the top of this post below, but I want to introduce another figure to illustrate the previous assertion:

This figure plots smoothed seasonal differences (year to year differences in monthly anomalies) for the four major global temperature data sets: HadCRUT, GISS, UAH and RSS. With the exception of the starting months of the satellite era (UAH and RSS), and to a lesser degree the starting months of GISS, there is remarkable agreement between the four data sets – where they overlap – especially with respect to the cyclical pattern of natural climate variation. This coherence gives me confidence that while there may be problems with the land-sea data sets, they accurately reflect the general course of natural climate variation over the period for which we have instrumental data. While we need to continue to insist upon open access to the data and methods used to chronicle global and regional climate variation, and refine the process to remove the biases which may be present from trying to make the data fit the narrative of CO2 induced global warming, it would be wrong to conclude that the “CRUtape Letters” prove that global warming does not exist. That has never really been the issue. The issue has been the extent of warming (have the data been distorted in a way that would overstate the degree of warming?), the extent to which it is the result of natural climate variation (as opposed to human influences), and the extent to which it owes to human influences other than the burning of fossil fuels (such as land use/land cover changes, urban heat islands, etc.). And flowing from this, the issue has been whether we really know enough to justify the kind of massive government programs said to be necessary to forestall climate catastrophe.

Figure 2 plots the composite smooth against the backdrop of the monthly seasonal differences of the four global temperature data sets:

Many readers may recognize the familiar episodes of warming and cooling associated with ENSO and volcanic activity in the preceding figure. With a little more smoothing, we get a pattern like that depicted in Figure 3, which other readers may notice looks a lot like the cycles that Anthony and I have attributed to lunar and solar influences (they are the same):

In either case, the thing to note is that over time climate goes through repetitive episodes of warming and cooling. You have to look closely on Figures 2 and 3 – it is much clearer in Figure 1 – but episodes of warming exist when the smooth is above zero, and cooling episodes exist when the smooth is below zero. Remember, by design, the smooth is not a plot of the temperature itself, but of the trend in the temperature, i.e. the year to year change in monthly temperatures. The intent is to demonstrate and delineate the range of natural climate variation in global temperatures. It shows, in effect, the trend in the trend – up and down over time, with natural regularity, while perhaps also trending generally upward over time.

Which brings us to Figure 1. Here we are focusing in on the last 30 years, and a forecast to 2050 derived by a simple linear regression through the (composite) smooth of Figure 3. (Standard errors have been adjusted for serial correlation.) There has been an upward trend in the global temperature trend, and when this is projected out to 2050, the average is 0.114°C per decade ± 0.440°C per decade. Yes, you read that right: ± 0.440°C per decade. Broad enough to include both the worst imaginations of the IPCC and the CRU crowd, as well as negative growth rates, i.e. global cooling. Because if the truth be told, natural climate variation is so – well, variable – that no one can say with any kind of certainty what the future holds with respect to climate change. Be skeptical of any statistical claims to the contrary.

I think we can say, however, with reasonable certainty, that earth’s climate will remain variable, and that this will frustrate the effort to blame climate change on CO2 induced AGW. Noted on the image at the top of this post is a quote from Kevin Trenberth from the CRUtape Letters™: “The fact is that we cannot account for the lack of warmth at the moment, and it is a travesty that we can’t.” Trenberth betrays a subtle bias here – he cannot acknowledge the recent period of global cooling. It is, rather, “a lack of warmth.” But he is right that it is a “travesty” that we cannot fully account for the ebb and flow of earth’s energy balance, and ultimately, climate change. I think Trenberth just sees it as a lack of monitoring methods or devices. But I think there still remains a considerable lack of knowledge, or understanding, about the mechanics of natural climate variation. If you look carefully at Figure 1, you will notice that there seem to be upper and lower limits to the range of natural climate variability. On the scale depicted in Figure 1 (the scale is different with other degrees of smoothing), when warming reaches a limit of approximately 0.08-0.10°C per year, the warming slows down, and eventually a period of cooling takes place, always with the space of just a few years. Homeostasis, anyone? While phenomenon like ENSO are the effect of this regularity in natural climate variation, they are not the cause of it.

In my opinion, what is the real travesty of the global warming ideology is the hijacking of climate science in the service of a research agenda that has prevented science from investigating the full range of natural climate variation, because that would be an inconvenient truth. We see this, quite clearly, in the CRUtape Letters™ where the Medieval Warm Period is just “putative,” and a rather inconvenient truth that needs to be suppressed. Or the “1940’s blip” that implies that global temperatures increased just as rapidly in the early part of the 20th Century, as they did at the end of the 20th Century, an inconvenient truth at odds with the narrative preferred by the IPCC.

It is a truism that “climate varies on all time scales.” With respect to the variability demonstrated here, I’m convinced that someday it will be acknowledged that variability on this scale is dominated by lunar and solar influences. On longer scales, such as the ebb and flow from the Medieval Warm Period, through the Little Ice Age, and now into the “Modern Warm Period,” I do not think climate science yet has any real understanding of the underlying causes of such climate change. If we are, as seems possible, on the verge of a Dalton or Maunder type minimum in solar activity, we may eventually have an answer to whether solar activity can account for centennial scale changes in earth’s climate. And I do think it is reasonable to conclude, at the margin, that human activity has had some influence. It is hard to imagine population growing from one to six billion over the past one and a half centuries without some effect. Most likely, the effect is on local and regional scales, but this might add up to a discernible impact on global temperature. But until all of the forces that determine the full range of natural climate variability are understood better than they are now, there is no scientific justification for the massive overhaul of economic and government structures being promoted under the guise of climate change, or global warming.


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Clever manipulation of graphs but the reality is very different – the planet has been warming at about 0.2C per decade for several decades and it still is warming at 0.2C per decade:

David Ball

Great post Mr. Copeland. Confirmation of natural variability boundaries. However, we must not forget OR minimize the control of a very important aspect of the this, the peer- review process. Also the bullying of people like Soon and Baliunas (to name just a few), who have some very important contributions to make. To be sidelined because your research doesn’t agree with the agenda is scientifically disgraceful. All sciences have been given a black eye in the minds of the public. They know not what they do.


Interesting analysis, thanks. Too bad that so many ordinary people and politicians have exactly zero comprehension of statistics that aren’t related to somebody’s batting average.

Climate Change

Opinion by Prof. Delgado Domingos in a google translation, published today in a portuguese newspaper. Delgado Domingos is a relevant Skeptic, emphasized by the fact that he is one of the pioneers of Numerical Weather Forecast. Delgado Domingos signed the Manhattan Declaration.


I like the first graph:
“Trend Forecast = 0.144degC/Decade +/- 0.440 degC/Decade”
So the noise is about 4x bigger than the signal.


IMO when a persons ego gets in the way of the search for truth or worse when it gets in the the way of others searching for truth it is time to stop blocking science and retire. this post is a wonderful example of the search for truth in its best form great post Mr. Copeland. And Icarus one of these days you will find the truth or it will find you I hope that day is not too unpleasant for you.

Old Goat

If only the last paragraph were to have some impact on those who would drag us through penury back to the dark ages, whilst stealing all our money and destroying our ways of life on the pretext that we’re all overburdening the atmosphere with carbon, it would be something.
Sadly, every day on television there are stories of flood, pestilence, drought, rain, storms and all manner of other plagues supposedly brought about by us naughty people for daring to develop the world in which we live, in order to thrive and prosper.
That’s the bit I can’t get my poor head around. With all this obviously trickery staring us openly in our faces, having to watch people like Ed Miliband posturing the need to cut production of a life giving element, and a life-enhancing gas in the name of alarmism, control, theft and inevitably global governance when most of us to have the sense to realise it’s all a huge con. And not being able to DO anything about it. It’s akin to being caught in a whirlpool – you instinctively know it is bad, and no good will come of it, but you are inexorably sucked down into oblivion.
On Channel 4 news tonight, John Snow had turned up in Brazil encouraging the president “Lula” de Silva to whinge about global warming, whilst demanding binding edicts from Copenhagen, there seems to be no doubt in the minds of either Snow or that of the president that global warming continues unabated – and there’s no-one to say otherwise, so the Channel 4 viewers are continuing to be indoctrinated into the AGW religion. I used to like the Channel 4 news as it always seemed less childish and partisan than the awful BBC. I’m no longer of that opinion – they are probably as bad as each other.
I’ve noticed, too, that the “bedtime story” ad is back this evening, slightly modified but still full of the same misleading crap about CO2. Clearly the Advertising Standards Office are as toothless as the government, or in their pockets.
Maybe it’s all a bad dream and we’ll awake soon…


This morning on NPR’s “Fresh Air” (podcast not available yet, will post when it is) Michael Mann was on talking about Climategate and kept saying “[regardless, this decade will be the hottest on record]” and that this was “[consistent with the models]”
Seems to be well within the range of precedented warming to me when you don’t use cooked books. Nice work!




In other words, the null hypothesis looks like a winner here. The other major point is that “so what if the climate warms”?. It has before and it will cool again, living in sackcloth and ashes under a bridge will not affect it. My residence has a climate that varies by many degrees over the course of a year and if I really want to live in a world that is warmer by up to 6 degrees, I would take a short flight North in my own country. My real anger is with the so called “Climate Scientists” and their hysterical followers who tried so hard to close off consideration of the null hypothesis.


“Trenberth betrays a subtle bias here – he cannot acknowledge the recent period of global cooling.”
That’s because there isn’t one.


I see what you did there icarus. I’m not impressed.


“It might also come as a surprise, to those who reckon me for a skeptic, that I do not think that anything was revealed that suggests that the global temperature data set maintained by CRU was irreparably damaged by these revelations”
I agree with your conclusion that the variability exceeds the trend, but is it not true that if the differenced data is integrated one comes back to the original anomolies, and that if these are not “irreparably damaged”, then the AGW-ers can also claim that their work is essentially correct?


the planet has been warming at about 0.2C per decade for several decades and it still is warming at 0.2C per decade:
The graph you link to shows an increase of ~0.6° over the period 1965 to ~2008 (by eyeball). Call that four decades, and we have an average increase of 0.15° decade, which is closer to the 0.114° claimed in the post than your assertion of 0.2°. That is the highest rate that can be shown from the chart, since it excludes the first two decades that showed (roughly) no warming – reflecting those reduces the warming over the period you cite to ~0.1° / decade.
Next time, try not to post your refutation as your “proof” ‘mkay?


Icarus, you are “waxing” too vocal on the trends. Trends exist. The AMO is a trend 30 years down 30 years up more or less. The up ended in the early 2000s and we are now heading into the down. So yes, any dataset such as the RSS that includes the majority of its years in the up phase will show a linear up trend. I imagine if you revisit this in 30 years you will have the last 30 years showing the down trend.
At the margin CO2 is a secondary climate forcer at best.

Peter Melia

Re the concealment of data practised by Messrs Mann & co. Today the Royal Society has started a website called “Trailblazing” which has some copies of early pioneers papers. Included is “Mr Isaac Newton’s” paper on light & prisms, which is a pleasure to read, not least because Newton included every possible scrap of detail about his experiment, sizes of the equipments, distances between components, angles as measured, just about everything measurable is there. Is there a lesson here?


Look at the graphs. Do they show natural variability or not? Did you read this article at all?


And then comes Jeff Id’s tAV posting today of the Fox News report regarding to what end uses the AGW cadre’s myoptic ‘science’ has been put to…
[b]The Religion of Global Government[/b]
Posted by Jeff Id on November 30, 2009
[quote]This is a stunner. Fox news just released some UN documents which are pretty clearly worded as to their intent.
Conservatives have long recognized the UN agenda of global socialization. It’s one of the main problems behind the global warming religion, a religion who’s status becomes more official with each passing day. A couple of documents have recently been reported at Fox news outlining how the topics of one UN organization will be shifted to achieve their wealth distribution agenda to the poor developing nations in the Southern hemisphere.
The document discusses further expansion of the environmental movement, including unelected committees to provide regulation and enforcement of global law. As leftists they fail to notice that these poor developing countries disadvantages are created by their leftist governments. They believe religiously that it’s the Northern countries fault that these poor disadvantaged communists cannot succeed. All governments are created equal and we should prop up and pay these dictators to help them achieve equal prosperity to the world. [/quote]
Add in the massive transfers of sovereign wealth envisaged through the legally binding world political organizations such as the IMF and IPCC/United Nations Framework Convention on Climate Change et al and one begins to see the collusions, knowingly or not, that the CRU’s cadre were/are aiding and abetting.
Much like many great conspiracies, once one pulls hard enough on a single loose, exposed thread, the entire interwoven (‘One-World-Order/Government’) fabric hopefully comes apart.
This, I believe, is what will be the true historical perspective written about ‘ClimateGate’ — The only few questions remaining to be answered are whether the interwoven cons will be fully exposed and abrogated before full implementation is legally enshrined and/or will we allow for true Climate science to be investigated, evaluated and confirmed.
Eisenhower had it right in his 1961 farewell address — he just had the wrong political entities…
[quote]In the councils of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex. The potential for the disastrous rise of misplaced power exists and will persist.
We must never let the weight of this combination endanger our liberties or democratic processes. We should take nothing for granted. Only an alert and knowledgeable citizenry can compel the proper meshing of the huge industrial and military machinery of defense with our peaceful methods and goals, so that security and liberty may prosper together.
Akin to, and largely responsible for the sweeping changes in our industrial-military posture, has been the technological revolution during recent decades.
In this revolution, research has become central, it also becomes more formalized, complex, and costly. A steadily increasing share is conducted for, by, or at the direction of, the Federal government.
Today, the solitary inventor, tinkering in his shop, has been overshadowed by task forces of scientists in laboratories and testing fields. In the same fashion, the free university, historically the fountainhead of free ideas and scientific discovery, has experienced a revolution in the conduct of research. Partly because of the huge costs involved, a government contract becomes virtually a substitute for intellectual curiosity. For every old blackboard there are now hundreds of new electronic computers.
The prospect of domination of the nation’s scholars by Federal employment, project allocations, and the power of money is ever present – and is gravely to be regarded.
Yet, in holding scientific research and discovery in respect, as we should, we must also be alert to the equal and opposite danger that public policy could itself become the captive of a scientific-technological elite.[/quote]


“In my opinion, what is the real travesty of the global warming ideology is the hijacking of climate science in the service of a research agenda that has prevented science from investigating the full range of natural climate variation, because that would be an inconvenient truth.”
Obviously, this is the main point. The IPCC is a political organisation mandated to seek out anthropogenic influences to the exclusion of natural influences, and CRU have followed this ideology fervently. However, since CRU have lost the original data, we cannot be certain at all what has been the rate of temperature increase over the twentieth century. Despite what these alarmists graphs show, it still comes down to the same old problem – don’t worry about the data, just trust us.


“Most likely, the effect is on local and regional scales, but this might add up to a discernible impact on global temperature. But until all of the forces that determine the full range of natural climate variability are understood better…”
And that will never happen under current conditions in the scientific community. The emails make that abundantly clear.
That is why the leaked emails are in fact irreparably damning to the AGW hypothesis. It reveals that climate science makes no effort at understanding any other possible drivers of the earth’s weather. These other possibilities are minimized, grudgingly shown, hidden, suppressed, smoothed, and homogenized, but they are not exhaustively explored.
Human understanding of the earth’s weather are still set to remain in the ditch for a very long time to come, because climate science itself is arbitrarily and even criminally ruling out non anthropogenic possiblilities, and pretending like the past climate variability is not as great as it is today.

tim c

I think a good question to ask is do we have enough good stations with long enough runs of data to make a real determination?

Icarus (12:17:55) :
“Clever manipulation of graphs but the reality is very different,” and then Icarus manipulates his own graphs on WoodForTrees [which is a good site, but it’s kind of hypocritical to accuse the author of “manipulation,” when Icarus is doing exactly that].
The global temperature hasn’t changed more than a few tenths of one degree since 1980: click
Regarding manipulation — and before anyone panics — let’s look at a global temperature graph with a normal y-axis plotted in whole degrees: click
Icarus isn’t fooling anyone here. What we see is natural warming following the Little Ice Age. If CO2 caused global warming the temperature would be shooting up. Instead, it’s declining: click


Re Icarus
A chart made of garbage is still garbage


Please explain why then there was a negative cooling by your standards from 1940 to 1980?
Your hypothesis is falsifiable with a turn of the knob. Do some reading, come back with a better argument.


Icarus (12:17:55) :
Clever manipulation of graphs but the reality is very different – the planet has been warming at about 0.2C per decade for several decades and it still is warming at 0.2C per decade:

Don’t fly so near the sun mate.


Interesting article, but as ever, I find the spaghetti graphs largely indecipherable. Is there any way to do them in “layers” so that you can look at individual plots separately or in relation to each other? The “composite overlay” approach is one of the means that was used to “hide” the decline (it was impossible to see amongst the other bits of spaghetti).
I recognize that in a blog, it’s probably too much to ask (if I had the computer skills, I’d try to do it myself – alas, no such luck), but for people who are spending significant time creating these files and analyses, is there not a relatively easy way to do it? Just asking (and this should not in any way be taken as a criticism by the author).


Mr. Copeland–
Your summary is a much more succinct and clear assessment of the state of “Climate Science” and the statistical basis of natural variability than I could ever give. The only point I personally would ephasize, is that the alarmists’ extraordinary claims require extraordinary proof, and at best the data record is ambiguous.
Speaking of alarmists– Icarus, you are a pathetic wretch. The last week shows that all of those databases you cite to are most likely hopelessly corrupted for the same reasons as the CRU data. They cannot be relied upon to make definitive statements about recent or future ‘warming’. The fact that you go on with your religious fervor as if nothing has happened is, well, pathetic. At this point we can only reasonably rely on historical raw data and 30 years of satellite data. Very thin evidence on which to make any legitimate prediction of future temperatures, in fact the lack of reliable data makes any prediction a fools’ errand– see Copeland’s post above.
I do however think your choice of name is appropriate– A MYTH.


The error on the trend is computed wrong. You need to take into account the number of data points in the fit. If you do it right, then you should get a trend closer to (I guesstimate) ~0.05 C per decade, which is what everyone’s eyeballs are telling them.
Come on, people.

Rob R

Keep an eye on what EM Smith is doing with the GIStemp code and data. When the various regional temperature datasets are corrected for the drift in mean elevation, mean latitude and UHI I suspect that the warming trend in these indices will be reduced to about 1/3 of what GISS has previously been reporting. It is likely that many of the same issues infest the CRU global and regional temperature indices. The fact that the global anomaly products from these two organisations march in step does not constitute verification of either or both.


Woops I meant to say the error on the trend ought to be closer to 0.05 C per decade.


11/30/2009 3:25:16 PM
From Wall Street Journal..November 30th 2009 – News Re:Indian Glaciers..
Most suggestions of rapid melting are based on observations of a small handful of India’s 10,000 or so Himalayan glaciers. A comprehensive report in November by senior glaciologist Vijay Kumar Raina, released by the Indian government, looked more broadly and found that many of these glaciers are stable or have even advanced, and that the rate of retreat for many others has slowed recently.Jeffrey S. Kargel, a glaciologist at the University of Arizona, declared in the Nov. 13 issue of Science that these “extremely provocative” findings were “consistent with what I have learned independently,” while in the same issue of the magazine Kenneth Hewitt, a glaciologist at Wilfrid Laurier University, agreed that “there is no evidence” to support the suggestion that the glaciers are disappearing quickly. A cornerstone of the global carbon regulation push has been high concern about evidence that glaciers are retreating worldwide. Glaciers are a crucial source of the Earth’s stored water. The “star” glacier, if you will, has been the Himalayan Saichen glacier, 74 km long and the largest outside the polar regions.India’s Ministry of Environment and Forests has released a comprehensive report on the Himalayan glaciers by the eminent Dr. V.K. Raina, ex-Deputy Director of the Geological Survey of India. According to his report, the Saichen glacier has “not shown any remarkable retreat in the last 50 years.” In fact, it is growing.

M. Essenger

Has anybody looked at the fact that the correlation between cosmic ray intensity and temperature ends about the time of “hide the decline”
I have two questions:
1) Could it be that current temperatures are not much higher than they were in the 30’s and 40’s as Karlens work would suggest and if so, how would that correlate with cosmic ray intensity? A match?
2) If current temperature estimates are correct and cosmic rays/sun activity are the main driver of temperature/climate. How large is the excess warming presumably caused by CO2.
Is it 10% 20% 50% of total warming?
Are there any good graphs on this or have any of you reflected on this issue?


“But nothing was revealed that suggests that the global temperature data sets are completely bogus, or unreliable”
So all the flub in the Harry Read Me file regarding the databases being in a sorry state of affairs means nothing?

Perry Debell

I wonder, does the Icarus who chooses to post here, truly understand his fate?
Philosophically shot down.


Could someone who truly understands these plots explain the obvious difference between the data presented by Icarus and the data presented here?
I believe the four different temp. data sources are in general agreement- yet, somehow, you can’t get graphs for any one of them from different sources to always agree. How can Icarus have graphs that show .2-.4 degree differences in temperature in any one year for HadCRU data?
There’s no doubt now that figures lie and liars figure, and that CRU has HIDDEN data- but until ONE chart of data is agreed to as most representative of global average temperature trends (first, raw data, and then, adjusted for UHI), there will be no real consensus.
Once there is consensus on trends, then hopefully we can rule CO2 out as the primary driver, and focus on just how much effect it actually has.


A veteran meteorologist, Anthony Watts, had reason to doubt the reliability of US Surface Temperature Records so he founded http://www.surfacestations.org and set out to audit 1,221 weather stations operated by the National Weather service.
After surveying over 70% of those sations, he issued a report that states:
“(W)e found that 89 percent of the stations—nearly 9 of every 10—fail to meet the National Weather Service’s own siting requirements that stations must be 30 meters (about 100 feet) or more away from an artificial heating or radiating/reflecting heat source. In other words, 9 of every 10 stations are likely reporting higher or rising temperatures because they are badly sited.” (Pg. 1) The report concludes, “the raw temperature data produced by the USHCN stations are not sufficiently accurate to use in scientific studies or as a basis for public policy decisions.” (Pg. 17)
It gets worse. We observed that changes in the technology of temperature stations over time also has caused them to report
a false warming trend. We found major gaps in the data record that were filled in with data from nearby sites, a practice
that propagates and compounds errors. We found that adjustments to the data by both NOAA and another government
agency, NASA, cause recent temperatures to look even higher.
The conclusion is inescapable: The U.S. temperature record is unreliable.
About the author of the study:
About the Author
Anthony Watts is a 25-year broadcast meteorology veteran and currently chief meteorologist for KPAY-AM radio.
He got his start as on-air meteorologist for WLFI-TV in Lafayette, Indiana and at KHSL-TV in Chico, California. In
1987, he founded ItWorks, which supplies broadcast graphics systems to hundreds of cable television, television, and
radio stations nationwide. ItWorks supplies custom weather stations, Internet servers, weather graphics content, and
broadcast video equipment. In 2007, Watts founded SurfaceStations.org, a Web site devoted to photographing and
documenting the quality of weather stations across the U.S.
Garbage in, garbage out.


Gavin, er, I mean Icarus, quit trying to hijack the thread. Aren’t enough people coming to your blog anymore?


Great post. Thank you.
Can’t we avoid confusion for the public by too many different graphs?
How if we use only one of such pictures, explain it in detail, show it over and over again, getting finally the stupid stick out of the public mind?
ONE picture tells more than thousand words, not hundreds of them.
Makes sense?


Would someone who understands these things please explain the difference between Mr Copeland’s graphs and those posted by Mr Icarus at 12:26.


The increase in temperatures as measured by Hadcrut is denoted as an anomaly compared to the 1950-1980 time period. Who decided that temperatures during the 1950-1980 time period were normal? Why a 30 year time span and why not 50-100 years and based on what criteria would you determine what time period to use?
It’s equally as likely that the time period we are in right now might be defined as “normal” for temperature. That would explain why temperatures have been flat.
It’s equally as likely that the 1950-1980 time period was cherry picked by the natural climate cycle “denialists” in order help push forward a flawed theory of AGW and produce a reason to fund their paychecks for the next few decades.


So with the error range being 4x the plotted trend, we have no statistically significant trend at all!

David Holliday

As someone who read through a good portion of the HARRY_READ_ME.txt file I beg to differ with Mr. Copland’s statement “…I do not think that anything was revealed that suggests that the global temperature data set maintained by CRU was irreparably damaged by these revelations.” The validity of the datasets and code are seriously in question following the release of this information.
Hat tip: The Devil’s Kitchen


You just aren’t applying the right “adjustments”, that’s all:


Would you specify the formula you use to get the “smoothed seasonal differences” that you plot and explain why it’s an appropriate transformation of the raw data?

Hugo M

Which brings us to Figure 1. Here we are focusing in on the last 30 years, and a forecast to 2050 derived by a simple linear regression through the (composite) smooth of Figure 3. (Standard errors have been adjusted for serial correlation.)

Is it really statistically sound to regress against a smoothed composite? Isn’t this method falling short of Rahmsmoothing, as the projected steepness depends on filter width and a arbitrarily choosen starting point? How do you calculate error bounds for this projection?

Jim Steele

“In my opinion, what is the real travesty of the global warming ideology is the hijacking of climate science in the service of a research agenda that has prevented science from investigating the full range of natural climate variation, because that would be an inconvenient truth.”
Excellent summary, I think this is the key. Too much attention is being diverted to other issues. The real horror story is how data, peer review and climate blogs have been/are being manipulated to create an exaggerated story and avoid any other explanations, and in turn control the flow of money. Instead there has been a flow of money to new “reseearch” not investigating all the variables of climate but hypothesizing what will happen in the future if CO2 keeps rising, always assuming CO2 is the driving variable. Such futuristic research is not science as it can not be tested, but it sure helps direct the flow of money.

“Reality” is different. Sorry, I know, no personal attacks.
So let’s say this..
NUMBER ONE, what data is this based on? The LAND DATA from the USA?
Check http://www.surfacestations.org on that.
The “composite data from the CRU”?
Check “Climate Gate” for that.
Aside from the concept that AVERAGE TEMPERATURE IS MEANINGLESS and
every PHD who has published such data SHOULD BE DEFROCKED, don’t make
me laugh.
OH, please, use AUTHORITY on this. I love it. What a joke.


Calm down, he is showing the “year to year differences in monthly anomalies”, not the anomaly. Why not discuss the interesting periodicity instead.


Good work Basil, and your charts illustrate perfectly that the global temperature is always going down and the earth is pretty good at keeping the energy balance fairly steady over time.
With regard to global temperature trends, they contain zero information about climate. Temperature is a poor proxy for the myriad of energy transfer mechanism that comprise the Earth’s chaotic climate system, and being non-linear you can cherry pick any trend you want from the data, depending on the time period you choose (as Icarus so elegantly proves). Once you start adjusting the very sparse proxy data and thermometer record too, hockey sticks can easily be produced, as demonstrated so well by Briffa’s carefully selected Yamal tree.
I think the quote from Kevin Trenberth in the hacked CRU Letters, “The fact is that we cannot account for the lack of warmth at the moment, and it is a travesty that we can’t.” is revealing. It shows the frustration the guy is feeling, that after spending god knows how much money on climate science the scientists involved still don’t have a clue. We still don’t know enough about climate systems to even accurately predict weather more than a few days forward, let alone get it right 10 years ahead.
Climate research will make no progress while it clings to the absurd premiss that you can predict the future by observing what happened in the past, then applying some pattern matching or clever statistical analysis. Instead we need to examine how each of the turbulent systems work in harmony to produce the effects we see. Science has become very good at solving linear problems, but still struggles to deal with dynamic chaotic non-linear systems.
In the mean-time politicians can use this lack of knowledge to control the world. Nothings going to change here any-time soon.