Is the warming in the 20th century extraordinary?

More to add to this. Each data point from the Vostok ice core represents about 20 years of the Holocene interglacial period. So each point represents a 20 year average of temperature. That is why only a few points are needed to represent 100 years.
The average temperature for the past 20 years is 0.26 °C. That is within a single standard deviation of the for the past 8,000 years of the Vostok record.
Here is a high resolution chart of the Vostok data.
Within a single standard deviation. That is all the current warming shows…..
John Kehr

It seems as if the Earth’s temperature variations are within natural climate variability.

“The Spatial Extent of 20th-Century Warmth in the Context of the Past 1200 Years”
http://www.sciencemag.org/content/316/5833/1844.1.full

I have also done this over the entire paleoclimate record. I don’t think there is really a correlation at all of temperature versus CO2 (and it is certainly less than 3.0C per doubling). So, other factors are more important in driving the historical climate. Maybe CO2 contributes, but it can only be 20% to 30% of the variation.
http://img801.imageshack.us/img801/289/logwarmingpaleoclimate.png

The criticism of this will be that we are now in special times, that is, there is an anthropogenic input of CO2. Therefore there is no reason to expect this warming trend to behave like past warming trends.
The article is saying that all past warming trends have been self-limiting. The warmists will say (with justification) “but it’s different this time !”.

I love the posts.
Waiting for consistency on the long range models for this weekend’s east coast storm.
Scott’s World of Weather has today’s prediction for Sunday.
http://sabolscience.blogspot.com
Scott Sabol
FOX 8 Meteorologist

Well done once again Frank.
I believe this is quite an important piece of work and deserves scrutiny.
WUWT has a large community of bloggers who understand these types of work.
I would implore some of you to play the devils advocate (or reviewer if you will) and attempt to falsify or improve Franks already good work.
Studies like this can put paid to the oft repeated meme ‘unprecedented’

> Catastrophe? what catastrophe?
A grant funding catastophe if the warmists get rumbled.

Oddly enough, I find this the best argument against CAGW. The idea of an inherently unstable climate has always been a ludicrous concept in my mind. This gives the argument some teeth.
Many thanks.

Typo: If positive feedbacks where strong why do temperature rises end so systematically?
Very interesting analysis, and a great read! Many thanks!

Stand by for the predictable argument from the advocates of Catastrophic Anthropogenic Global Warming. It will come in the form along these lines:
“But by analysis the Earth should be in a cooling phase of 1° per century and we have unprecedented warming of over 1° per century yielding a true rise of over 2°.” Blaw, blaw, blaw … and it is all caused by human activity and carbon pollution from burning dangerous fossil fuels.

The fact that some 4.5 billion years after the creation of the Earth, we are here able to debate this issue in itself establishes that the Earth’s climate is self regulating and that if there are any tipping points, they are almost impossible to achieve. If all the violent forces of nature have not led to a tipping point, there is nothing that man can realisticic do to create one. Just think of the past climatic and geological history of the Earth and what she has been through to realise that the present scaremongering is simply ridiculous.

Now publish it in a scientific journal … let is stand the critique of people more experienced than us. Of course some would claim the peer review process is corrupted (I strongly disagree), but if that were the case, on what grounds do non-scientists know which plausible person to take seriously.

Excellent analysis …
I think about the only sure thing anyone can say about climate, is ever since plate tectonics closed the Isthmus of Panama, some 3 million years ago, the next glaciation epoc is right around the corner. And nothing we can do about that. If we were smart, we would prepare for that inevitable eventuality.
BUT — The fact that we try and measure things with the instrument precision we have today, with instrument precision of yesterday, means we have at best a guesstimate. And therefore, most of the deviation what we see would fall within the measurement errors of yesterday’s precision. It’s the dreaded consequence of advancing technology.
Look at it this way, not too long ago, people thought the Earth was the center of the universe — Just a minor error. BTW, nothing I say here faults the analysis, only adds caution and context.

The standard response to this very cogent post is that CO2 heating is hiding in natural variation just waiting to bite us in the ars when we least expect it. What was that seriously funny statement? Climate change has (or will) worked its way into weather and once there you can’t get rid of it? Or something like that. These pro-AGW pseudo-sciency arguments are beginning to compete with that very funny scene in Monty Python’s “The Life of Brian” in the courtyard filled with “The end times are coming” preachers.

Anyone trying to claim long droughts, harsh 5 month winters, fierce tempests, devastating floods, or whatever else weather phenomena are “unprecedented” or “extraordinary” they need to read this.
“Weather has been documented by early meteorologist and historians for many centuries. A Chronological Listing of Early Weather Events provides a weather resource for years 0 A.D. to 1900 A.D. ” by James A. Marusek.
http://www.breadandbutterscience.com/Weather.pdf
Fascinating and revealing.

Using the exact same data that is used to prove global warming,
a person could make a more solid argument that CO2 drives cooling.
And the CO2/temp data would support it…………

“unless my definition of interglacial periods is totally wrong.”
more grammar police..sorry.
Very nice analysis. Yet again it’s up to the CAGW crowd to prove the current warming is unusual, and that their models are realistic.

Another blow to the modern Puritanical (AGW) belief system….
Time for another “Sinners in the hands of an angry Gaea ”
speech by Algore-in the middle of a blizzard.
Thank you, Frank.

Antarctic air temperature derived from ice core temperature can’t be used as a proxy for global average temperature with fine granularity. Supposedly these past two decades are the warmest in at least 1000 years but Vostok actually got a little colder. The oxygen balance in snowfall (one method of determining air temperature in the past) at Vostok, which gets about a 2 millimeters snowfall per year, is going to be the average of many years. It takes 500 years to accumulate a meter of snow while fierce winds have been pushing it around relentlessly drifting back and forth keeping it well mixed. The same mixing will also keep absolute ice temperature at best an average over a similar amount of time. So all you can really say from Vostok core data is that there weren’t any lengths of time where average temperature over a period of centuries didn’t exceed this or that and only really at the south pole which may or may not have tracked the northern hemisphere or even much of the southern hemisphere.
I think the main point is that CO2 is higher now than can be seen in the core data for past periods and while that is also subject to averaging over decades it at least appears to track global CO2 partial pressure (well mixed atmosphere). So assuming the CO2 spike from 280 to 390ppm (and growing) is something novel, which it appears to be at least as far back as ice cores go, then we are in unexplored interglacial territory.
Personally I hope this unexplored territory is an indefinite and perhaps very long lived end to the ice age of the past few million years but I tend to doubt anthropogenic greenhouse contribution is enough to prevent the return of the glaciers more or less right on schedule.

Humbug, Baa : Yes! Scrutiny is what it takes to take this futher 🙂
Thanks.

@frank Lansner:
In several places you have a comma when it appears you intend a decimal point.

Welcome back Mr. Lansner! As a technician, not a scientist, I find it frustrating to argue with doctors and PhD’s trained in the medical sciences who find evidence of CO2 driving temperature in the Vostok (a Vostok series) and Greenland graphics. If one is paying attention to what one sees, it really is inescapable that we are living on borrowed time as far as the amount of time the current interglacial warm period has left. I have used Mr. Lansners ’09 article from WUWT many times. Here is another good reference using the ice core data, from WUWT. I have come to the conclusion that AGW is a belief rather than an evidence based phenomenon. It is the same old thing- you can make people believe anything you want if you present the evidence in the right way- even scientists and doctors. What I can’t understand is why it matters wether or not CO2 is the driver? The evidence from Antarctica and Greenland is clear- the chance of a huge temperature increase in the next 20,000 years or so is remote to nil. The chance of the earth getting very cold for 50,000+ years or so is very high and getting higher with each passing year.
What does it take to make people see that we are in the midst of only the fifth small interlude where the earth’s temperatures were in an average range equal to current temps? That, as in the story of the ant and the grasshopper, we better start preparing for what the evidence shows is inevitably heading our way. That is if the cycle of the last 800,000 years or so continues. Here and here (see graph- “Global Temperature and Atmospheric CO2 over Geologic Time”) are two graphs that show that what the AGW buffs consider “warming”, is, in reality, not very warm at all! Leave it to the Geologists to bring in a little long term perspective. It appears that on an even longer time scale over many millions of years, we are actually in an “ice-house” period with average temps in the 10 deg C to 12 deg C range. If the earth enters a “hot-house” period, average temps could reach the 25 deg C range! Just the thought that human activity could affect the earth’s climate cycles, or that man could change or alter those cycles significantly is the height of arrogance. As an example, suppose the earth began having eruptions on the scale of the Siberian or Deccan traps? Do these statists actually think they could seriously have an effect on those events??? I think that AGW is more an attempt to gather power and pick our pockets while they have the chance.
re: the “typos” or awkward enlish phrasing, I would refer readers to the editor’s note in the ’09 article: “(Note from Anthony – English is not Frank’s primary language, I have made some small adjustments for readability, however they may be a few passages that need clarification. Frank will be happy to clarify in comments)“

Canadian Mike says:

My response to your question is that CO2 levels have been much higher in the past than they are now and yet temperatures obviously didn’t go off the charts.

Well, it may not have gone off the charts but it was much warmer. Note that since temperature depends logarithmically on CO2 concentration, a concentration of 16 times higher is only expected to produce a temperature change 4 times as large as a doubling would.

In fact, from what I have read, there appears to be very little correlation between historic CO2 levels and temperature.

That may be so from what you have read…but it suggests that you are not reading the actual peer-reviewed scientific literature. It is difficult to get accurate and high-resolution estimates of both CO2 and temperature but when they have been obtained, the correlation is generally found to be strong. Of course, on long enough timescales, one also has to consider other important factors that affect the climate (like continental drift).

Since the natural CO2 molecule is the same as the anthropogenic CO2 molecule (in fact they are all natural) I see no reason why current (and historically low) levels of CO2 should be any concern at all.

Well, those who actually study past climates would beg to differ with you. Their evidence suggests that, if anything, the current model estimates for climate sensitivity may be too low to account for the paleoclimate data: http://www.sciencemag.org/cgi/content/summary/sci;306/5697/821

I believe most AGW modellers tacitly admit this when they introduce mythical “forcings” into their models to achieve the desired temperature increases.

They don’t introduce mythical forcings. What they do find, however, in looking at the 20th-century temperature record is that it does not constrain climate sensitivity very well because, among other things, there are some very real forcings (mainly aerosols) whose values are very uncertain. This is why better empirical constraints on climate sensitivity are derived from paleoclimate data and such things as looking at the climate response to the Mt. Pinatubo eruption.

JohnWho, Canandian Mike has answered you, but I’d like to be a trifle more direct.
You are committing the “natural vitamin” fallacy, which is humanocentric hubris. Carbon dioxide has no maker’s marks or serial numbers. It has one carbon atom and two oxygens, and if it had more or fewer of either, or something else in addition, it would be something else with different properties and therefore not be part of this discussion. The same can be said with equal force of the carbon and oxygen atoms themselves, and of the protons and neutrons that make them.
So it doesn’t matter if carbon dioxide is made by little pink daisies or dark satanic mills. It’s carbon dioxide, wherever it came from. There are many sources of carbon dioxide, from the respiration of fleas to orogenic eruptions, and the only question is how much, because once a carbon dioxide molecule has escaped into the wild its source doesn’t influence what effect it will have.
A huge proportion of the AGW hysteria is driven by the same hubris. We look about us and see great local effects of human activity, and “reason” that our effect on the planet as a whole must be in equivalent proportion. It ain’t so, but try to tell that to the little minds that desperately search for some evidence that they are not just relevant but important to the Cosmos.
Regards,
Ric

GeorgeG says: December 9, 2010 at 9:14 am:
@frank Lansner: In several places you have a comma when it appears you intend a decimal point.
That is the European convention, George. We use decimal points, they use commas. It does take a bit of getting used to though.

Joel Shore says:
Well, those who actually study past climates would beg to differ with you. Their evidence suggests that, if anything, the current model estimates for climate sensitivity may be too low to account for the paleoclimate data: http://www.sciencemag.org/cgi/content/summary/sci;306/5697/821
Those who study past climates have graphics taken from data that literally unlink CO2 from temperature.
IceHouse or HotHouse shows that our current avg. temps are in the IceHouse phase of the earth’s climate history, irregardless of CO2. You warmists seem to think that a rise of 2,3, or 4 deg C is alarming. Try global avg. temps of 22 deg C! Or, if the cycle shown in the Vostok graphs holds for another hundred thousand years or so, we will probably see global avg temps in the 6 deg. C range with a mile of ice on top of Chicago! Either way, neither CO2 nor insignificant man has anything to do with it.
Global Temperature and Atmospheric CO2 over Geologic Time shows that there is no correlation whatsoever between CO2 and temps.
You just refuse to see what is there.

c1ue says:
“Its different this time.
Much like all the scammers with Ponzi scheme, Internet companies, and what not.”
“Ponzi schemes” – i.e. Social Security?

c1ue says:
“Its different this time.
Much like all the scammers with Ponzi scheme, Internet companies, and what not.”
Ponzi Scheme – i.e. Social Security?

dwright says:
December 9, 2010 at 5:45 am
I’m a bit slow on “climate science” but how can one trust an ice core to trap a gas like CO2?
Molecules are slippery things, do we know how cold gas reacts with a frozen liquid?
Resolution for temperature signal in ice cores is much better than for carbon dioxide trapped in bubbles. The former is calculated from oxygen isotope ratio of water, which does not migrate much once frozen while the latter one, being in gas phase does, so this temporal resolution for Antarctic plateau, where snow accumulation is slow is anywhere between 2000 to 6000 years. Air bubbles do not get enclosed until the firn-ice transition zone is reached, which is around a depth of 90 m at Vostok and even then there may be some thin super cooled liquid water at ice crystal boundaries, enriched in salts excluded from the solid phase. This can further serve as a vehicle of CO2 migration since this particular gas is highly soluble in cold water.
Therefore temperature and CO2 signals derived from ice cores are not directly comparable. But this article is about temperature alone, so the caveat does not apply here.

RockyRoad says:
December 9, 2010 at 4:22 am
“First fix: “the raw total raw CO2 warming ” (remove one “raw”)
[Fixed, thanks]”
I would keep both of them for another sentence. Raw, raw for this great article!
Also, Mike D raises the huge point of the impacts of aboriginal burning which the AGW discussion as well as the so-called ‘wilderness movement’ ignores. The latter ignores it very deliberately because it shatters their whole premise.

Frank Lansner says:

John, its widely accepted that CO2 itself will just create a minor temperature increase. The “dangerous” part is that IPCC et al. claims that just a little heat today wil create huge positive feedback and thus huge temperature increase.
So, John, CO2 – natural or not – is only itself resulting in a tiny temperature increase. The hypothesis is that just a little heat (from human Co2 or anything else) will make the world go hot like h… due to feedbacks.
What i did was just to check the past, if we earlier has encountered any such huge heat spikes. But there are hardly any. If it takes only a little heating to provoke a big heating then we should have seen big heatings before. And we havent really, thats the point. And more, we also see that the present temperature increase appears very normal in compare with interglacial temperature increases. This does NOT suggest that co2 has the effect you might fear.

Here is where your logic is wrong:
(1) You are exaggerating the role claimed for positive feedbacks. The “bare” response to the radiative change due to doubling CO2 is about 1.1 C. The prediction is that feedbacks multiply this number by a factor of about 2 to 4 (thus giving us a range of about 2 to 4.5 C). This is hardly turning something “little” into something “huge”. Rather it is making something reasonably big even bigger.
(2) Given that, you simply haven’t demonstrated that the lack of large heat spikes is due to a lack of feedbacks. It could simply be due to the fact that forcings have been fairly small (especially once you say that “the initial temperature increase from glacial to interglacial is not included”). [You also seem to be ignoring larger temperature changes that are seen over short time periods that are thought to be more local than global changes…but I guess one could at least justify that.]
So, your conclusion that the sort of rises predicted by the climate models are unprecedented (at least looking back over a short enough period of time and ignoring the larger events I mention) does not imply that they can’t occur. They are unprecedented for exactly the reason that worries scientists: namely, that the perturbation that we are imposing on the climate system by raising CO2 far above levels seen for at least 600,000 years, and probably several million years, is an unprecedented perturbation, at least in recent times.
Furthermore, by looking further back in time and by not ignoring the glacial-interglacial transitions, one can actually estimate the forcings and get empirical estimates of the temperature change that occurred and can use this to estimate the climate sensitivity. And, as I noted in a previous post, most of the estimates come out in the range of sensitivities that the climate models suggest, if not higher.

Bill Illis says:
December 9, 2010 at 4:42 am
I have also done this over the entire paleoclimate record. I don’t think there is really a correlation at all of temperature versus CO2 (and it is certainly less than 3.0C per doubling). So, other factors are more important in driving the historical climate. Maybe CO2 contributes, but it can only be 20% to 30% of the variation.
http://img801.imageshack.us/img801/289/logwarmingpaleoclimate.png
Excellent presentation of an important point. It would be great to have the source data for this chart (the data points at least) – is this available?

nofate says:

Those who study past climates have graphics taken from data that literally unlink CO2 from temperature.
IceHouse or HotHouse shows that our current avg. temps are in the IceHouse phase of the earth’s climate history, irregardless of CO2. You warmists seem to think that a rise of 2,3, or 4 deg C is alarming. Try global avg. temps of 22 deg C! Or, if the cycle shown in the Vostok graphs holds for another hundred thousand years or so, we will probably see global avg temps in the 6 deg. C range with a mile of ice on top of Chicago! Either way, neither CO2 nor insignificant man has anything to do with it.

Indeed, the difference in global average temperatures between the last glacial maximum and now was about 5 or 6 C and, as you note, that difference was enough to make the ice atop Chicago a mile high. It was also enough to make the sea levels many tens of meters (or even a couple hundred meters?) lower. So, yes, global temperature changes of 2, or 3, or 4 C do seem quite alarming to me.

Global Temperature and Atmospheric CO2 over Geologic Time shows that there is no correlation whatsoever between CO2 and temps.

Interesting…You have presented a plot that combines together two disparate sources. And, one is a modeling of the CO2 levels (with huge errorbars as that figure indicates if you look closely). It is fascinating that people who call themselves “skeptics” seem to blindly believe any data from sources without any attempt to verify the data, find out what the errors are in the data, or what the time resolution is in the data. And, that is leaving aside the issue of the other forcings that operate on timescales of tens of millions of years, like continental drift.
The fact is that as the general trend has been that as the resolution and precision of the paleoclimate record of past CO2 and temperature levels improves, any apparent lack of correlation between the two seems to yield to quite good correlation (at least going back a few million years…beyond that the data isn’t generally good enough yet, except for dramatic events like the PETM and the issue of other significant forcings operating on longer timescales becomes more important).
This is why there is a gulf between what paleoclimate scientists have concluded and what some skeptics have concluded from throwing together a plot using temperature and CO2 data from different sources (one modeled) with large error bars and various problems with resolution, not to mention being over timescales where we know there were other larger forcings operating. This is the difference between using science to learn about the world and misusing it to just confirm what one’s ideology makes one want to believe is true.

Hi Joel.
You open up a long row of subjects, so lets start with someting simple:
In this article “Is the warming in the 20´ieth century extraordinary?” i show the warming 1900-2010 vs the heat spikes of the interglacials. I make clear that the present warming data includes UHI and warming adjustments, but on the other hand the Vostok data normally is expected to vary more than the global average. So its a qualitative compare but stil, these are the data we have and does not really suggest something quite extraordinary about the present heating.
Can you to some degree agree on this?
Next you calculate your way to expected CO2-sensitivity of 2-4,5 K. I do something else. I use the IPCC´s own “best estimate” of 3 K and then Hansen older “best estimate” estimate of 6K. I then search for peaks between IPCC best etimate and Hansens estimate. (IPCC gets their 3 K from an average of several different papers, including papers up to 5 K CO2 sensitivity).
The raw CO2 effect: As demonstrated, there are around 9,25 raw CO2 doublings to equal the total raw total CO2 contribution. Using 1,1K gives a total raw CO2 contribtion of over 10K, that is around a third of the total present greenhouse effect. But due to the greenhouse dominans of mostly water, the real fraction of raw CO2 effect is often reffered to as 15% or so, half you value. If true you should use 0,5-0,6K.
Or take the MODTRAN model, here you get around 2 – 3 W/m2 per doubling:
http://hidethedecline.eu/media/CO2sensi/fig1.jpg
And since its normally accepted that we have 4-5 W/m2 = 1 K, again we end up with 0,5 – 0,6 K for Co2 sensitivity.
Lindzen even suggests 0,5 K for CO2 sensitivity INCL. feedbacks?
As I remember, the latest IPCC report uses around 72% feedbacks vs 28% raw Co2 warming. This would give 0,76 K raw CO2-warming from their best estimate of 3K incl feedbacks.
BUT! lets just use 1 K for CO2 sensitivity as you mention.
Under these circumstances a warming of 1K should lead to 3K warming incl feedbacks (IPCC) or up to 6K (Hansen and others).
So if anything gave a direct warming of 1 K earlier in interglacials we should have seen a warming continue to 3 – 6K.
But this has hardly ever occured in interglacials at all.
There can be 2 reasons
1) IPCC and Hansen are wrong
or
2) There has never been a direct raw warming of 1 K in the many 10 thousands of interglacial years.
See temperatures. http://www.physics.rutgers.edu/ugrad/140/vostok_ice_core.jpg
And what did i then conclude?
“It is thus surprising that IPCC and others with big confidence can claim large temperature rises of up to 3 – 6 K as most likely result from just a minor temperature increase, for example induced by CO2 warming.”
Dont you find it surprising, that IPCC and others can claim to be “confident” of the strong feedbacks when we dont see many big warming peaks (3-6K) in the temperature data? Perhaps you think that these ice core data strongly supports this IPCC claim? If so, I would like to know how you argue for this.
K.R. Frank

This blog post represents a kind of straw man argument. The statement made in the hockey stick paper, is that the current temperature increase is a unique event in the past 1000, years, and didn’t include the interglacial periods for the past 400,000 years. The projection of global warming does not rely on the hockey stick paper, or any characterization of the current temperature change as being unusual. It relies on the physical understanding of the effect of CO2 on the climate, including feedback.
In fact a look at the Vostock ice core data, shows how the projected effect of CO2 increases can be associated with huge changes in temperature.
Looking at the Vostok graphs, one sees that a change in CO2 from 180 to 280ppM was correlated with an increase of temperature of 10C. The CO2 change was less than one doubling. This means it is possible for CO2 to have a huge temperature effect.
It is true that CO2 increase was not the only change driving temperature. The tilt of the earth’s axis and precession of the earths orbit triggered it, and different feedbacks including changes in albedo due to snow and ice as well as the CO2 changes were responsible for amplification of the intial orbital forcing. Some kind of simulation modeling which takes many factors into account is needed to determine the effect of CO2. This is what Hansen and other researchers have done to come up with the range of climate sensitivity that is quoted by climate scientists.
http://naturalscience.com/ns/articles/01-16/ns_jeh2.html
Of course the change in CO2 in the modern period is much faster than what happened during the ice ages, and CO2 is a primary driver of warming, rather than a feedback factor, as it was in the ice ages. The physics behind it is the same. Since the heat capacity of the oceans is large, and the change in net energy flux is small, the full surface temperature change that is associated with the change in CO2 from 280 to 390ppM has not yet occurred. Another 0.4 to 0.7 C increase is expected even if the CO2 concentration stays where it is.

eadler says:
December 9, 2010 at 6:03 pm

This blog post represents a kind of straw man argument. The statement made in the hockey stick paper, is that the current temperature increase is a unique event in the past 1000, years, and didn’t include the interglacial periods for the past 400,000 years. The projection of global warming does not rely on the hockey stick paper, or any characterization of the current temperature change as being unusual. It relies on the physical understanding of the effect of CO2 on the climate, including feedback.

The actual net effect of additional CO2 in the atmosphere is in reality an unknown at present. Any claims that all or most of the warming of the 20th century is due to CO2 are, at full face, inaccurate. Such claims neglect to account for any natural warming OR for other influences by man such as land use.
On the other hand, the warming is not unique to the Holocene. The warming, statistically, can be said to be expected. It occurred right on schedule. Though at present we cannot explain, in full, what causes the cycle of warming we can likewise, not accurately determine to what extent man has influenced warming until we can separate the natural from that anthropogenically induced. Such task is difficult due to a lack of full understanding of either. At this point theoretical SWAGs are what is being generated. Little more.
Fortunately there are those who realize the ‘debate’ is not over. They continue doing valid science in search of fact and truth. The ‘debate is over’ group (not a crowd) continue with self-serving rhetoric and little real science. Time and reality will continue to defeat them.

steven mosher says:
December 9, 2010 at 9:09 pm
phlogiston says:
Franks method is solid? Well, I’m sorry he did does not establish a repeatable or testable method. There are methods that mathematicians have developed for diagnosing sensitivity from observations.
Thanks for these useful references to studies of sensitivity in the palaeo-record. I will try to look them up over the weekend.
However Lansner’s article and argument were not about sensitivity. Thus my point about inappropriate conflation of his point with other topics. He is just making a simple point in a rather innovative way – starting a new debate, not jumping on board a well-established one i.e. sensitivity.
Lansner is (if I am right) just characterising the statistical nature of temperature fluctuations in the ice core record, and asking whether the trends and patterns visible in this fluctuation support the hypothesis that small increases in global temperature are inevitable amplified by positive feedback to become larger ones . This argument is implicit in the writings of the IPCC and James Hansen. It emerges instead that the 20th century warming is slap bang in the middle of the “normal” distribution of many hundreds of similar temperature rises during recent interglacials – an in being about 100 years long his approach even suggests (“predicts” would put it too strongly) that this increase is over and that temperature decrease is likely to follow.
The sort of temperature fluctuation he analyses is of a fractal nature, so in fact although he restricted it to the interglacials, the same analysis would hold true if extended to the whole Vostok and other ice core records. The fluctuations arising from a system exhibiting non-equilibrium nonlinear dynamics is described by a log-log relation – plot log of size of temperature changes with time against log of the frequency of changes of each magnitude, and you get a straight line. This means lots of small changes, fewer big changes, much fewer very big changes. It is a universal feature of such systems.
Understanding the nonlinear / nonequilibrium nature of the climate system fundamentally changes the role or feedbacks. It is absurd to characterise such a system as having positive feedback at a global level. Instead local and time-limited positive feedbacks operate, but they run their course and terminate (Bob Tisdale uses the term “saturate”). The ENSO is an example of this. The potential for local positive feedbacks to occur characterises the system as a reactive or excitable medium – the tension between positive and negative feedback results in emergent spatio-temporal pattern formation. These patterns are the climate – which cannot be analysed by simple linear global heat balance equations, because it is nowhere near equilibrium.

This is a very simple and elegant idea. I hope this can be developed and that in time it will appear in peer-reviewed scientific papers. If this idea is right – and I think it almost certainly is – then it is of the utmost importance, for it strikes at the very heart of that ruinous belief known as CAGW.
A couple of years ago I read a piece in New Scientist. It said in effect: okay, so the ice core data shows that the CO2 follows the temperature – but this means it’s a positive feedback, so we’re doomed after all. It probably never occurred to the writer that if there were a positive feedback at work then it would appear clearly in the data. As far as I’m aware the ice core data shows no sign of the temperature being driven by CO2. And this excellent piece by Frank Lansner takes it even further. Quite possibly the ice core data provides the biggest and most important disproof of CAGW – and maybe of AGW as well.
Chris

Woops my Joanne nova Writings:
http://joannenova.com.au/tag/lansner-frank/
K.R. Frank

Hi Joel.
You open up a long row of subjects, so lets start with someting simple:
In this article “Is the warming in the 20´ieth century extraordinary?” i show the warming 1900-2010 vs the heat spikes of the interglacials. I make clear that the present warming data includes UHI and warming adjustments, but on the other hand the Vostok data normally is expected to vary more than the global average. So its a qualitative compare but stil, these are the data we have and does not really suggest something quite extraordinary about the present heating.
Can you to some degree agree on this?

Not really. First of all, as you note, the Vostok data is expected to have about double the variability of the global average for the glacial – interglacial transitions. I assume it is similar (or maybe more) for fluctuations on shorter timescales. The UHI and warming adjustments, I think is, by contrast, mainly a fictional complaint.
Second of all, I think you need to talk to someone very knowledgeable about this data to find out how reliable such temperature proxies are expected to be for the sort of timescales and variations that you are looking at. I.e., I could imagine there might be a level of noise in the proxies.

The raw CO2 effect: As demonstrated, there are around 9,25 raw CO2 doublings to equal the total raw total CO2 contribution. Using 1,1K gives a total raw CO2 contribtion of over 10K, that is around a third of the total present greenhouse effect. But due to the greenhouse dominans of mostly water, the real fraction of raw CO2 effect is often reffered to as 15% or so, half you value. If true you should use 0,5-0,6K.
Or take the MODTRAN model, here you get around 2 – 3 W/m2 per doubling:
http://hidethedecline.eu/media/CO2sensi/fig1.jpg
And since its normally accepted that we have 4-5 W/m2 = 1 K, again we end up with 0,5 – 0,6 K for Co2 sensitivity.
Lindzen even suggests 0,5 K for CO2 sensitivity INCL. feedbacks?

Basically, everyone serious agrees that the “raw CO2 effect” is about 3.7 to 4 W/m^2 and that this translates to around 1.0 – 1.2 C warming…Lindzen agrees with this (albeit he thinks the feedbacks are negative and thus reduce it) as does Spencer, as far as I know. If you want to argue about this, you are really headed way out into the weeds.

So if anything gave a direct warming of 1 K earlier in interglacials we should have seen a warming continue to 3 – 6K.
But this has hardly ever occured in interglacials at all.

And, what significant forcings do you propose there were during the interglacials? The reason there haven’t been dramatic warmings is because there haven’t been very significant forcings. Even the total forcing from the glacial to interglacial conditions is only estimated to be about 8 W/m^2 or thereabouts.
If you can come up with compelling evidence of significant forcings during interglacial times (and small temperature responses to those forcings), then you have something. Just arguing that the temperature doesn’t vary that much during the interglacials without any attempt to figure out what the forcings are doesn’t give you anything useful.

Steve Mosher and Joel Shore:
This is how one would calculate the climate sensitivity of CO2/GHGs based on the ice age data:
Fill in this table: the question marks are where one shouldn’t really know what the value is:
http://img641.imageshack.us/img641/4003/iceageforcingmath.png
Now suppose I told you the Ice and Vegetation Albedo forcing was really -12.0 watts/m2 (based on the actual climat ice age maps and cloud changes forcing information). Then one can see how cherry-picking values can result in the fake climate sensivities that Hansen’s climate science have indoctrined people with.
The Real table looks like this which then produces a real climate sensitivity of just +1.27C per doubling of CO2/GHGs.
http://img683.imageshack.us/img683/4827/iceageforcingreal.png

Joel Shore, You ave some correct points ere and there, but my “stomack” feeling is that your not unbiased – i may be wrong.
You just start out claiming that UHI has no impact (!???!?!?!?!?) and then you just go ahead as if you where not on thin ice.
-and you must be claiming the about warming adjustments (!) for your logic to make som sence.
And: The temperature difference between average interglacial and average glacial is around 8K, and there are souces that suggests that globally its more like 6K. Ok lets say that the difference is 50% then. But the truth is, the availability of real global temperature data for a period like the last ½ mio years is not that impressive, so we are guessing a little here.
But you just claim 100% without a blink, “it is expected” you say.
But what really interesting then is that you do not use this “info” in both ways, only in the direction that supports critic of my point. You forgot something, Joel: If you where correct, then all temperature rises in fig 3-5 should be half size when conparing to global. This means, that the IPCC “CONFIDENT” expectations to future temperature rise on fig 3 is not corresponding to 3K but 6K…… and only then can we say with REAL confidence that the IPCC expectations of temperature rise is EXTEMELY UNLIKELY!!!
Do you undersatnd this? If you are correct in your opninion “global-temperatures-should-be-multiplied-with-2-to-compare-with-Antarctic-temperatures” then the “best estimate” from IPCC is 6 K as reponse to one single CO2 doubling temperature.
So suddenly IPCC is 4 times higer in their expectations than the normal upper limit of around 1,5 K for these temperature rises.
And then back to your “fresh” “No-UHI” claim (!)I think a good place to start is the biggest and the best investigation ever, and its done by Thomas Karl. The force of his study is, that he used mostly UNadjusted data, so the issue of how city vs. rural temperatures are alligned are not excisting. UNadjusted because the resaerch took place in the mid 1980´ies.
More, he used ALL relevant US city-rural pairs yielding around 4-500 compares. US has more long temperature series than rest of the world in GHCN, so a full US resaerch like this is very relevant. Here are his raw results:
http://hidethedecline.eu/media/UHIworldtour/USAKarl.jpg
These values are just for the period 1900-1983 so you have to multiply with around 1,3 or so to get nearer the true 1900-2010 values. So very vey fast we will have a UHI signal that covers perhaps 20-50% of the mostly city-measured supposed global warming temperature signal of around 0,65-0,7 K.
Even Phil Jones later China research show an AVERAGE UHI false warming of 0,5K ! (And you think other developing countries like India, Mexico, Brasil, do not have massively growing cities to yiels a similar result perhaps?)
And temperature corrections: Alone for the USA, it is directly black on white knowledge that cant be denied: Adjustmet are more than 0,4K ! I can document.
But you, Joel, just say: NO UHI! NO adjustments! 100% more signal in Antarctic data without using this info as it should: It makes IPCC claims of temperature rise 100% more in dissagreement with previous temperature rises sown on the figures.
etcetcetc.
And then if you have time: Can you in any way argue against that we actually have around 9,25 doublings for CO2 ?
And after you hopefully has explained the above problems, Lindzens 0,5K for CO2-sensitivity (and many others with low feedback expectations): You are missing the point of the article.
The article baically show ten thousands of years with shorter temperature rises that seems not that large and also timelimited, that is, natural mechanisms normaly make an end to temperature rises. The small earlier temperature rises does not support IPCC in their belief that smaller temperature rises for “sure” will lead to much larger temperature peaks.
this is the point
THEN we start explaining WHY that is. WHY are the old temperature peaks small?
and in this context, it is not important if the small temperature rises in the past are caused by
1) a small raw CO2 signal of 0,2K + positive feedback of 0,3K
or
2) a raw CO2 signal of 1K – negative feedback of 0,5K
In either way, we end up with a small temperature rise in the past that simply does NOT make IPCC “confident” predictions of large temperature rises now supported in data. So if Lindzens idea is, that is estimation of CO2 is a low 0,5 K due to large negative feedbacks this IS a sound explanation as to why we dont see many IPCC-like large temperature rises in the past.
I am not religious about WHY the IPCC “confident” large claims are not that well supported by low temperature variability in the past, I just pinpoint the problem.
((And finally as a 100% less important side remark: As a real skeptic, yes, I use logic and not “who believes what”. Never mind who says waht, I do NOT find it likely that CO2 should be responsible for one third of the Earths greenhouse effect – 9,25 * 1,1 = on third of greenhouse effect. AND I do NOT find it likely that all heating due to an atmosphere should be caused by greenhouse gasses, and thus i find the Earths combined greenhouse effect of 30 K to be exxagerated. Saturn has hardly any greenhouse gasses in the atmosphere but shows no difference in isolating effect when doing a simple compare. Titan orange-red armophere is STUFFED with greenhouse gasses but may have the very poorest isolating atmosphere in the solar system… But this is another conversation! ))
K.R. Frank

Bill Illis says:

Now suppose I told you the Ice and Vegetation Albedo forcing was really -12.0 watts/m2 (based on the actual climat ice age maps and cloud changes forcing information). Then one can see how cherry-picking values can result in the fake climate sensivities that Hansen’s climate science have indoctrined people with.
The Real table looks like this which then produces a real climate sensitivity of just +1.27C per doubling of CO2/GHGs.
http://img683.imageshack.us/img683/4827/iceageforcingreal.png

So basically, you are saying that you have calculated the forcings due to albedo changes between the LGM (last glacial maximum) and now, gotten an answer significantly different (by about a factor of 2) from what scientists have determined, and we are supposed to blindly believe your results?
And, just as a side note, even if you were correct, your calculation concludes that doubling CO2 produces a warming that is one quarter the size of the difference between the ice age and now. Quadrupling CO2 (which we apparently have enough coal to do quite easily) would produce a warming half the size of the warming between the LGM and now. Those sorts of changes are still nothing to sneeze at.
Of course, the reality is that scientists have estimated the albedo forcing to be lower than you claim. Furthermore, as Hansen has pointed out, this whole way of estimating the climate sensitivity takes the change in albedo due to ice sheet and vegetation changes to be a forcing, not a feedback. In the present case, such effects will be feedbacks, further increasing the warming due to the change in greenhouse gas levels. (Hansen estimates this doubles the climate sensitivity from ~3 K to 6 K over the long run…although other scientists have noted that the effect will probably not be that great in going from the current state to a warmer state because there is less ice sheets to melt than there were in going from the LGM to the current state.)

“Joel Shore says:
December 11, 2010 at 8:02 am
Bill Illis says:
So basically, you are saying that you have calculated the forcings due to albedo changes between the LGM (last glacial maximum) and now, gotten an answer significantly different (by about a factor of 2) from what scientists have determined, and we are supposed to blindly believe your results?”
Hansen’s “tuned” ice and vegetation Albedo estimate is 0.307 (versus today’s global Albedo of 0.298).
Well, all that additional ice and desert and grassland and tundra in the ice ages certainly changed the Albedo by more than that.
This is how Hansen’s estimate plays out by latitude. It is effectively impossible to get a number that low. It is tuned so that he gets a temp C change per watt/m2 of 0.75C/w/m2 so that his 3.0C per doubling still works.
http://img251.imageshack.us/img251/2764/albedobylatitude.png

Bill Illis
Dec 11, 4:54 pm
It was not published however (I assume the team got involved).
Business as usual for the (climate) science community.
Human nature is even more difficult to regulate than CO2 emission.

Anthony –
(1) Were the papers that he referred to actually kept out of the IPCC report in the end?
(2) Was he objecting to the papers because he didn’t like the conclusions or because he thought they were garbage?
(3) Even if one could find a situation where a paper was rejected by a referee for questionable reasons, does that we mean that we are entitled to assume that any such paper we find a preprint of that hasn’t appeared in print falls into that category? I have had a paper of mine rejected for reasons that I did not think are justified but I don’t think that justifies me to assume that any time any paper by me gets rejected it must be for unjustified reasons.
REPLY: Nice spin buddy, your comment is still BS. On #2 I can’t be in the mind of Phil Jones or Mikey, or Jim or any of those. #3 is hypothetically irrelevant. I can only go by what was written. What is written is that Phil Jones said he and Trenberth would work to keep papers out. The central question is: can the team be trusted? The answer that keeps coming back by words and deeds is “no”. Just like in Wikileaks, there’s lots more that we have not seen I’m sure. – Anthony

Bill,
It is not just Jim Hansen who has made these estimates and it is not like Hansen’s are out-of-line with others. Here is a paper from close to 10 years ago: https://e-reports-ext.llnl.gov/pdf/240137.pdf (which just happens to be the first scientific paper that came up when I typed “estimates for albedo at lgm” into google). They conclude that “the climate sensitivity is about 1 K W” m2 with a range of +10%. This would imply a global warming in response to a doubling of CO2 in the range of about 3.1 to 3.7 K”. So, their estimate of the sensitivity is slightly on the high side of Hansen’s.

Bill and Joel,
I also looked at that paper and noted a couple of things. First of all 11 W/m2 is very high, and requires a substantial ice albedo equivalent to perfectly whitening everything beyond both arctic and antarctic circle from black before (or the NH alone down to 60 N). Even, if the LGM did that, examining what they mean by that number, it seems to be the surface albedo change only, and would therefore be overestimated by not considering cloud-cover before or after the change which would surely reduce the difference by the pre-existing cloud albedo. I don’t know the average arctic daytime cloud-cover, but I expect it is quite high.

Bill,
Do you calculate albedo from the point of view of the sun? This diminishes the effective values at high latitudes significantly. For example above 60 N is less than 3% of the earth’s disk as viewed from infinity but over the equator, but you should check my geometry, and also I am not sure if this is the relevant value to use.

This makes even a 3% albedo increase very difficult. Wouldn’t you agree? Their glaciers only got to 50 N over some of the continents. Also when considering winter, sea-ice would seem to be a positive feedback compared to water, by radiating less energy to space, and I don’t think that was accounted for.

as the ice moves toward the equator as in the last glacial maximum when it got to 40N in North America and seasonal sea ice got down to 40N on the North American Atlantic coast.

At least for the land ice, what happened in (eastern) North America appears to be the exception rather than the rule:
http://en.wikipedia.org/wiki/File:Iceage_north-intergl_glac_hg.png
Bill,
I would say until you make some serious calculations and publish them in the peer-reviewed literature, I am not sure why you expect people (other than those predisposed to believe anything along these lines) will take your claims seriously.