From Global Warming Questions -IPCC
How the IPCC invented a new calculus
A new form of calculus has been invented by the authors of the the IPCC’s Fourth Assessment Report (AR4), in order to create the false impression that global warming is accelerating.
How the new IPCC calculus works
Here’s how it works. Look at the following graph:
Now consider the following question:
Is the slope of the graph greatest at the left hand end of the graph, or the right hand end?
By just looking at the graph, or by using old-fashioned calculus developed by Newton and Leibnitz, you might think that the slope of the graph is similar at both ends. But you would be wrong. In fact, the slope is much greater towards the right hand end of the graph. To prove this, we need to apply the new calculus developed by the IPCC. To do this, we draw a sequence of straight-line best fits backwards from the right-hand end-point:
This clearly shows how the slope of the graph is in fact increasing.
How IPCC calculus is used in the IPCC report
Here is one of the key graphs from the AR4 report:
The graph is Figure 1 from FAQ 3.1, to be found on page 253 of the WG1 report. The slope over the last 25 years is significantly greater than that of the last 50 years, which in turn is greater than the slope over 100 years. This ‘proves’ that global warming is accelerating. This grossly misleading calculation does not just appear in chapter 3 of WG1. It also appears in the Summary for Policymakers (SPM):
“The linear warming trend over the last 50 years is nearly twice that for the last 100 years“.
Thus, policymakers who just look at the numbers and don’t stop to think about the different timescales, will be misled into thinking that global warming is accelerating. Of course, we could equally well start near the left hand end of the graph and obtain the opposite conclusion! (Just in case this is not obvious, see here for an example). A similar grossly misleading comparison appears at the very beginning of chapter 3, page 237:
“The rate of warming over the last 50 years is almost double that over the last 100 years (0.13°C ± 0.03°C vs. 0.07°C ± 0.02°C per decade).“
How did this get through the IPCC’s review process?
The IPCC reports are subjected to careful review by scientists. So how did this blatant distortion of the temperature trends get through this rigorous review process? The answer to this question can now be found, because the previous drafts of AR4, and the reviewer comments, can now be seen on-line. (The IPCC was reluctant to release these comments, but was forced to do so after a number of freedom of information requests).
The answer is quite astonishing. The misleading graph was not in either the first or the second draft of the report that were subject to review. It was inserted into the final draft, after all the reviewer comments.
It is not clear who did this, but responsibility must lie with the lead authors of chapter 3, Kevin Trenberth and Phil Jones. Here is the version of the graph that the reviewers saw in the second draft:
Note that in this version there is only one trend line drawn.
So why was this graph replaced by the grossly misleading one? Did any of the reviewers suggest that a new version should be drawn with a sequence of straight lines over different time intervals? No. One reviewer made the following remark:
‘This whole diagram is spurious. There is no justification to draw a “linear trend” through such an irregular record’
… but his comment was rejected.
It is the same story with the misleading comment in the SPM mentioned above (“The linear warming trend over the last 50 years is nearly twice that for the last 100 years“). This statement was not in the original version reviewed by the scientists. It was inserted into the final draft that was only commented on by Governments. The Chinese Government suggested deleting this, pointing out that:
‘These two linear rates should not compare with each other because the time scales are not the same’.
Well done to the Chinese Government for spotting that. Too bad their valid comment was ignored by the IPCC.
h/t to Roger Carr
PH,
I think the point is why not show the trend for the linear portion between 1880 and 1910? or between 1910 1940? What’s the point of any of this piecewise linear fitting? What sort of hypothesis are you testing? Nothing physical that’s for sure.
Peter Hearnden wrote “I don’t think … anyone can … show … where anyone … asserts these trends or graphs ‘prove’ anything.”
If the trend lines in the graph were not meant to prove anything, why were they inserted at all? Why were they mentioned in the SPM? Merely to prove that the IPCC is about “spin”, not “proof”?
What AW has done here is a poor man’s “proof by contradiction”, assume a method means X (where X implies the data set has some sort of accelerating trend), apply it to a perfectly valid data set (a trig function) where the method shows X when clearly the data has no trend at all. Poof the technique vanishes in a puff of logic.
“”” RonPE (14:17:32) :
For small laughs, an engineering prof asked us “What’s the derivative of acceleration?”
Looking us in the eyes, he would say “JERK!” to emphasize the double entendre. “””
Well that prof must have had in mind, that ultimate in catastrophically sluggish functions:- exp(-1/x^2) .
Now that function is zero at x = 0, and also its derivative is zero at x = zero, and so is its second derivative; and its third derivative.
So this poor chap starts off at zero with zero velocity, and zero acceleration; and also zero rate of increase of acceleration.. In fact, every derivative of that function is zero at x = zero; so how in the blazes would that ever get anywhere ?
But somehow, at X = 1, that slowpoke has managed to stagger all the way up to 1/e or 37% (of 1).
Don’t ask me how; I reckon it is magic.
Hmm, the last two plots aren’t showing up for me (I even tried a “relaod”. Were the originals moved? Can’t really evaluate the article without those.
On an OT note, the whole Greenpeace threat fiasco made it to the opinions page of the Colorado State University newspaper, and the author did a good job of raking Greenpeace without being over-the-top.
Original Mike and Pat Hearnden… are your comments serious?
If you are, do this little “thought experiment”:
Take the data and pretend you are back in 1940. Do the SAME ANALYSIS and see what you find.
What you will find is the linear trend was accelerating at an EVEN HIGHER RATE back then.
So now ask yourself this question:
If the rate of acceleration of the temperature trend was HIGHER in 1940 than it is today, what does it say about the impact of CO2 on the temperature trend?
Hint: CO2 growth was virtually non-existent prior to 1940.
The bottom line is this:
If you believe this type of trend analysis is correct, then you must also agree that CO2 is NOT the cause.
Can’t have it both ways.
“”” Peter Hearnden (14:14:44) :
This is a non story that, I can only assume, is here to provide today’s opportunity for harumpfing.
Those lines just show the linear trend over a variety of times. I don’t think here anyone can (or will) show either that the trends are wrong, or show where anyone (other than Anthony (who I assume has written this piece)) asserts these trends or graphs ‘prove’ anything. “””
Well it might be an indicator that “trend” means absolutely nothing.
Actually, the graph is a plot of real actually measured and masticated data; and the only “trend” that it really has is where it goes to from the most current observed value; to whatever value will be measured next; and that up and coming value, is totally unpredictable from anything that has happened before, as a simple look at the graph would reveal.
The furure is kinda like that, which is why they call it the future.
Peter Hearnden (14:14:44) :
Why are you defending the indefensible? Why are you pretending that nobody takes any notice of these graphs? These are both in the WG1 and the Summary for Policymakers. They are clearly designed to alarm the casual observer. You have to be honest and admit this.
Why not also draw a trendline from 1860 and 1910, and show the current rate is nothing unprecendented? The statement “The linear warming trend over the last 50 years is nearly twice that for the last 100 years“ is clearly designed to alarm and motivate policy makers to act. It should say ‘The linear warming trend is similar to the trends observed in 1880 and 1910, and follows the general warming trend observed since 1850.’ Even Phil Jones admitted that these prior periods showed the same rate of warming.
Second to the actual content of the graph, what about the IPCC process. What is the point of having reviewers if the editors can just put in whatever they like in the final draft, without any reviewers reviewing it? This is categorically not an inclusive process.
Shouldn’t you be correctly saying the fake line is directed at the world’s useful idiots, the food stuff of politicians. I doubt politician even open the books they get.
The way I see the data on the graph, there is an acceleration for a decade or so near the end, but the rate of temperature change has been accelerating, decelerating and flipping from warming to cooling over the whole timespan and one could show as great an acceleration during earlier periods.
As we know, there has been a deceleration, possibly a reversal, for the last decade or so, which isn’t shown on the graph.
Its not so much that they have invented a new calculus, they have simply cherry picked the data to give the answer they required to support their story. Nothing new there!
As can be clearly seen by the progression of the trend lines, the slope will continue approaching vertical, and soon we’ll have a rise of 10 anomaly units per year. Then we will all die.
In other news, evolution has begun prepping our possible replacements. New multi-cellular animals discovered on the the floor of the Mediterranean that “…do not depend on oxygen to breathe and reproduce…” (The headline material says “first animals” and I’m thinking about the ones living deep under water at the sulfurous volcanic vents.) So if we do go insane on planetary CO2 reductions, get caught in an ice age where cooling oceans soak up so much CO2 that the plants shut down, and O2-CO2 cycle respiring species go away, life on Earth will go on. Isn’t that good to know?
Well, I understand what they are trying to show, i.e. that the rate of temperature growth has increased more in the later industrial period.
Statistically, this is not an uncommon treatment (breaking up the series and showing the slope for smaller time units). However, to be consistent, they should compare apples to apples & compare the smaller slopes to each other, not only to the overall slope for all data. This will always give a wrong impression.
For example, if they were to do the same technique for the 25 years including 1915 to 1940 in the Global Mean Temperature graph, I think the slope would be nearly identical to the 25 year period of 1980-2005 (eyeballing it anyway).
Very misleading, if we were to do this for the past winter compared to previous 10 winters, we’d be out buying shares in snowblower and parka manufacturers. Just more evidence of how the AGW priests cook the books to sow panic among the policymakers and public.
If that is their methodology, will they NOW take the 12 years since 1998 and do the same thing?
No. They argue that 12 years does not a trend make.
When it goes UP, use the shorter trendline.
But when it goes DOWN, one takes the LONGER trendline. It’s not FAIR to use the shorter trendline THEN!
(Heads I win, tails you lose?)
@chris B. (14:19:07) –
Agreed – and the 1860-1880 one is maybe even steeper. Phil Jones agreed on these in an interview – but didn’t mention it in the IPCC. Sandbagging piece of dung, really.
The one constant is that the steep incline always ends in a peak and then there is another decline – one that can’t be hidden.
That is the most stressful thing for the Hockey Team – that since they drew so much attention to their predictions that they can’t hide this decline.
Peter Hearnden in fact there has been a long discussion over at Our Changing Climate (“Global average temperature increase GISS HadCRU and NCDC compared”) that demonstrates that the GISS time series violates the assumptions underpinning linear regression, so the trends and confidence limits quoted in Fig 1 from FAQ 3.1 are meaningless (quite apart from the arguments being made here).
Notwithstanding this the IPCC Report says in the caption to Fig 1 “Note that for shorter recent periods, the slope is greater, indicating accelerated warming” and then references this Fig over a dozen times in the report (according to my lazy Google search).
FWIW, several of my old math teachers and university professors might have a stroke upon seeing that first diagram. Never use x for the hypotenuse, use h!
Not content with using cherry picked data, aka the hockey stick, AGW have here cherry picked their (faulty) method of measuring acceleration and then ignored the review process – as is standard practice it appears – you could not make this stuff up! It is so bad, nobody would believe it if you told them. You just couldn’t make it up.
I made my own “climate model” few weeks ago. I used following assumptions: there is some cyclic climate process that has period of approx. 60 years (recent minima 1860(?), 1910, 1975 and maxima 1880, 1940, 1998) and there has been some constant recovery from LIA. Furthermore, I considered impact of the average GHCN “adjustements”.
So, if we assume that there is a such periodical process, fix a minimum to 1910 and approximate that its amplitude is 0.48 K, and if we take that the recovery from LIA is 0.16 K / century (calculated form hadcet 1659-1900), we get something like this:
http://users.tkk.fi/kse/trend60lt_fixed.png
with linear trend of 0.29 K / century.
Next, if we deduct this “climate model” and average GHCN adjustments from HadCRUTv3, we get this:
http://users.tkk.fi/kse/hadcrut-adj-model.png
and the remaining linear trend is 0.061 K / century.
Does this prove anything? Definitely not – but certainly these were quite odd results considering that I didn’t do any “parameter optimization”…
Was going to say, (bu**er), but on second thoughts, upon my very word! This is the first time I have seen this “revolutionary new scientific method” demonstrated.
Is it really true you can just make stuff up? [snip] me where is R.Gates when you need it?
The bombshell for me is that it was inserted after the scientific review process.
This is shades of the 2nd report scandal over the change from AGW as inconclusive to AGW as aconclusive finding of the report — inserted after the scientific review. See http://www.sepp.org/Archive/controv/ipcccont/Item05.htm
It should also be mentioned that this graph has continued to be used even after it has been widely discredited by the IPCC, including Pachauri in his official speech at Copenhagen, for which he was roundly criticised for it on WUWT (I cant find the page).
It just keeps getting worse. But since these are all now effectively (world) government statistics, should we be surprised?
The economy is on the rebound too. And there’s no inflation.
One irony here is that the Chinese government, which pumps out whatever convenient economic statistics it needs for the moment, found this.
Speechless in Seattle (15:16:50)
If you mix “proof” with “spin” don’t you get “spoof”?
Alan Simpson: what do you need R Gates for, other than to try to make some money by betting against him on Arctic Ice levels?
CSIRO and BOM used this same “trick” here in Oz a couple of weeks ago, making dire claims from the trends from 1960-2009. This was quickly picked up by Jo Nova, Andrew Bolt, (and, ahem, me, at kenskingdom), showing that trends since 1910 are no cause for alarm. If in doubt, pick a shorter period to make your trend- works every time.
Doesn’t it say something about the IPCC’s commitment to truthfulness when China is pulling it up?
This whole graph is bogus. The entire Michael Mann/CRU/GISS/NOAA effort to reduce climate down to ONE number for every month is a mirage. It means nothing.
After reading Frank Lansner’s How not to compare temperatures I am convinced that all averaging does is flatten and flatten and flatten.
And the ultimate in flattening is to reduce everything to one number – and THEN go off and read something into that number – which doesn’t represent ANY of the data that went into creating that one number.
If you look at the proxy graphs in Frank’s post – which I have reason to assume are typical for all multi-proxy and mega-multi-station graphs – it is obvious that the average doesn’t tell us anything whatsoever about what is really going on. Single proxies and temperature traces are all OVER THE MAP. And each one is fairly NORMAL for that location or proxy.
And when one takes each one of those traces and compares them to that one number, NONE of them agree with the ONE number. The sacred number. The HOLY number.
The useless number.
What the average SHOULD be telling us is that the overall average stays within a narrow band of about 1C either side of some norm – and that is all.
We should then stop right there. And then go off and do something USEFUL.
Reading anything at all into that +0.5C to -0.5C graph is like priests trying to tell how many angels can fit on the head of a pin.
What is the REAL story is in all those huge variations in all those proxies and all those met stations. They tell us that EVERYPLACE ON EARTH is much more variable than that stupid GATA graph. Some places are wilder than others’ but very few follow that graph.
You have one number – what does that do? FOR ANYBODY? It allows someone to scream, “The SKY is Falling!” because of a rise of less than 1C. At EVERY POINT on the globe the temperature changes more than that in one hour and every hour on most days.
What Frank’s graphs show is that the heat is all over the place. When the heat from one area moves to another area, the first area cools and the second warms up – and usually in measurements larger than 1C. But the total heat stays essentially the same. And I challenge anyone to show us all that a 1C change at ANY point on the globe is a disaster.
ALSO: Proxies are single points. To have a single proxy represent the entire globe in past centuries and millennia is just plain WRONG. It is okay to have it there as a reference or a general IMPRESSION. But to have ANY single point or small group of points on the Earth represent the globe for a 100-year period or a 1,000-year period and then tell us it is meaningful as compared to the THOUSANDS of data points we now have (even if those are less than recent decades) is just WRONG.
As I commented on Frank’s post, those proxy datapoints should also show TIME uncertainty bars, because the C14 dates and the counts of the tree rings and ice cores is NOT an exact science, so every data point behind those single-line graphs actually is a horizontal line in itself.
And with all that +/- in BOTH directions, and with all the HUGE fluctuations in local and regional climate, attempting to conclude ANYTHING from swings of 0.01 in the GLOBAL average – other than this: THE GLOBAL AVERAGE IS VERY STABLE.
Mountains out of molehills. Climate catastrophes out of 1C or less waverings in that number. Is there a difference?
NO! THE EARTH IS NOT WARMING.
The otherwise useless “average” is within that narrow band – WHOOP DEE FREAKING DOO.
Around that average all KINDS of huge fluctuations are going on, some here, some there, and varying all the time.
As Dick Lindzen says OVER AND OVER AND OVER, “The climate is changing all the time. What’s the big deal?” But it doesn’t stay one way; it keeps oscillating in its multitudinous ways – EVERYWHERE. Changes come, and changes go.
Let’s all get scared when that ONE useless, meaningless number shifts another 0.2C.
Shame on the AGW people for their tempest in a teapot.
This does bring up an interesting point.
Could we have the derivative of the “smoothed series” plotted?