This is an attempt to redefine the graph made famous by Al Gore in An Inconvenient Truth that showed temperature leading CO2.
From a press release embargoed until 1PM EST 4/4:
Work that may clarify the relationship between carbon dioxide (CO2) levels and temperature at the end of the last ice age is presented in this week’s Nature. The study reveals that rising temperatures were preceded by CO2 increases during the last deglaciation, contrary to prior findings derived from ice cores that were thought to represent larger global patterns. These results support an important role for CO2 in driving global climate change.
Antarctic ice-core records indicate that CO2 may have influenced climate changes during the Pleistocene ice ages, which began around 2.6 million years ago and ended about 11,700 years ago. However, the exact role of CO2 in producing climate changes has remained unclear, partly because ice-core records only reflect local temperatures. To better understand the relationship between CO2 and global climate change, Jeremy Shakun and colleagues reconstruct global surface temperatures for the last deglaciation. They show that rising temperatures are correlated with, and generally lag behind, increasing levels of CO2.
The reconstructed global temperatures were produced using proxy records of temperature variability, such as those recorded in planktonic microorganisms. Anomalies in the correlations, such as in the Antarctic where the CO2 changes lag behind temperature, are explained by redistribution of heat between the Northern and Southern Hemispheres, the authors suggest.
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Here is the long form press release (h/t to junkscience.com):
Rising CO2 levels linked to global warming during last deglaciation
CORVALLIS, Ore. – Many scientists have long suspected that rising levels of carbon dioxide and the global warming that ended the last Ice Age were somehow linked, but establishing a clear cause-and-effect relationship between CO2 and global warming from the geologic record has remained difficult.
A new study, funded by the National Science Foundation and published in the journal Nature, identifies this relationship and provides compelling evidence that rising CO2 caused much of the global warming.
Lead author Jeremy Shakun, who conducted much of the research as a doctoral student at Oregon State University, said the key to understanding the role of CO2 is to reconstruct globally averaged temperature changes during the end of the last Ice Age, which contrasts with previous efforts that only compared local temperatures in Antarctica to carbon dioxide levels.
“Carbon dioxide has been suspected as an important factor in ending the last Ice Age, but its exact role has always been unclear because rising temperatures reflected in Antarctic ice cores came before rising levels of CO2,” said Shakun, who is a National Oceanic and Atmospheric Administration (NOAA) Post-doctoral Fellow at Harvard University and Columbia University.
“But if you reconstruct temperatures on a global scale – and not just examine Antarctic temperatures – it becomes apparent that the CO2 change slightly preceded much of the global warming, and this means the global greenhouse effect had an important role in driving up global temperatures and bringing the planet out of the last Ice Age,” Shakun added.
Here is what the researchers think happened.
Small changes in the Earth’s orbit around the sun affected the amount of sunlight striking the northern hemisphere, melting ice sheets that covered Canada and Europe. That fresh water flowed off of the continent into the Atlantic Ocean, where it formed a lid over the sinking end of the Atlantic Meridional Overturning Circulation – a part of a global network of currents that brings warm water up from the tropics and today keeps Europe temperate despite its high latitudes.
The ocean circulation warms the northern hemisphere at the expense of the south, the researchers say, but when the fresh water draining off the continent at the end of the last Ice Age entered the North Atlantic, it essentially put the brakes on the current and disrupted the delivery of heat to the northern latitudes.
“When the heat transport stops, it cools the north and heat builds up in the Southern Hemisphere,” Shakun said. “The Antarctic would have warmed rapidly, much faster than the time it takes to get CO2 out of the deep sea, where it was likely stored.
“The warming of the Southern Ocean may have shifted the winds as well as melted sea ice, and eventually drawn the CO2 out of the deep water, and released it into the atmosphere,” Shakun said. “That, in turn, would have amplified warming on a global scale.”
The researchers constructed a record of global surface temperature from 80 temperature reconstructions spanning the end of the Ice Age and found that average temperature around the Earth correlated with – and generally lagged behind – rising levels of CO2.
Peter Clark, an Oregon State University scientist and co-author on the paper, said changes in solar radiation were the likely trigger for the series of effects that followed. His 2009 study, published in Science, confirmed an earlier theory that wobble in the Earth’s axis, which changes the amount of sunlight captured by Earth, first caused melting of the large northern ice sheets.
“It has long been known that Earth’s slow wobble is caused primarily by the gravitational influences of the larger planets, such as Jupiter and Saturn, which pull and tug on the Earth in slightly different ways over periods of thousands of years,” said Clark, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.
Shakun said there is “an enormous amount” of carbon sequestered in the deep ocean.
“The Southern Ocean is connected to all the deep ocean basins,” he pointed out, “so the most likely mechanisms to draw it out of the ocean were certainly there.”
The question now, the researchers say, is how human-generated carbon dioxide will affect the planet when there isn’t an ice age.
“CO2 was a big part of bringing the world out of the last Ice Age,” Shakun said, “and it took about 10,000 years to do it. Now CO2 levels are rising again, but this time an equivalent increase in CO2 has occurred in only about 200 years, and there are clear signs that the planet is already beginning to respond.”
“While many of the details of future climate change remain to be figured out, our study bolsters the consensus view that rising CO2 will lead to more global warming,” Shakun added.
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The paper is at http://www.nature.com/nature/journal/v484/n7392/full/nature10915.html and named:
Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation
Jeremy D. Shakun, Peter U. Clark, Feng He, Shaun A. Marcott, Alan C. Mix, Zhengyu Liu, Bette Otto-Bliesner, Andreas Schmittner & Edouard Bard
Abstract:
The covariation of carbon dioxide (CO2) concentration and temperature in Antarctic ice-core records suggests a close link between CO2 and climate during the Pleistocene ice ages. The role and relative importance of CO2 in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than
global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO2 during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age.
METHODS SUMMARY
The data set compiled in this study contains most published high-resolution
(median resolution, 200 yr), well-dated (n5636 radiocarbon dates) temperature
records from the last deglaciation (see Supplementary Information for the full
database). Sixty-seven records are from the ocean and are interpreted to reflect sea
surface temperatures, and the remaining 13 record air or lake temperatures on
land. All records span 18–11 kyr ago and,85% of them span 22–6.5 kyr ago. We
recalibrated all radiocarbon dates with the IntCal04 calibration (Supplementary
Information) and converted proxy units to temperature using the reservoir corrections
and proxy calibrations suggested in the original publications. An exception
to this was the alkenone records, which were recalibrated with a global
core-top calibration41. The data were projected onto a 5u35u grid, linearly
interpolated to 100-yr resolution and combined as area-weighted averages. We
used Monte Carlo simulations to quantify pooled uncertainties in the age models
and proxy temperatures, although we do not account for analytical uncertainties
or uncertainties related to lack of global coverage and spatial bias in the data set. In
particular, the records are strongly biased towards ocean margins where high
sedimentation rates facilitate the development of high-resolution records. Given
these issues, we focus on the temporal evolution of temperature through the
deglaciation rather than on its amplitude of change. The global temperature stack
is not particularly sensitive to interpolation resolution, areal weighting, the
number of proxy records, radiocarbon calibration, infilling of missing data or
proxy type. Details on the experimental design of the transient model simulations
can be found in ref. 25.
The temperature stacks and proxy data set are available in Supplementary Information.
Full Methods and any associated references are available in the online version of
the paper at www.nature.com/nature.
PDF files
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- Supplementary Information (9.2M)
- This file contains Supplementary Text and Data, Supplementary Figures 1-30, Supplementary Tables 1-3, additional References and Supplementary Appendices 1-2.
Excel files
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- Supplementary Data (2.4M)
- This file contains Supplementary Data.
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Don Easterbrook has some initial thoughts on the Nature paper.
The paper is based on many assumptions without supporting data. Here are a few examples:
1. They assume that CO2 is capable of causing climate changes, even though 95% of the greenhouse gas (GHG) effect is from water vapor. In order to seriously consider CO2 as a causal mechanism, you first need to prove that very tiny increases in CO2 do indeed increase atmospheric water vapor. However, during recent warming, purported to be caused by increased CO2, atmospheric water vapor has not gone up, it has decreased slightly. CO2 by itself cannot cause significant warming because there is little of it in the atmosphere (0.038%) and CO2 accounts for only a few percent of the GHG effect.
2. They assume that the AMOC is the only driver of climate change, totally ignoring the influence of the Pacific Ocean, which covers almost half of the Earth’s surface and we can see in the modern data a strong influence of ENSO as a driver of climate changes (actually a closer correlation than the AMOC). They offer no evidence that the AMOC is the main and only driver of climate change.
3. They assume a hemispheric ‘see-saw’ of climate changes in which the North and South Hemispheres are out of phase, despite strong evidence in both hemisphere that climate changes were closely simultaneous, not out of phase with one another (Easterbrook, 2011).
4. The dismiss all other causal mechanisms by simply stating that they are only of ‘regional importance’, similar to the tactic of dismissing the MWP and Little Ice Age as only regional climate changes, not global. They also totally ignore the complete lack of correlation of CO2 with Holocene climate changes. They don’t even mention the very strong correlation of variation in 10Be and 14C with climate changes, suggesting a solar cause.
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The Antarctic Ice core graph is particularly troublesome.
In the long scale graph at top, I pointed out that the resolution of the temperature reconstruction diminished as the sample got older. Willis responded to my query with this:
The resolution for temperature drops, as does the CO2 resolution, because the ice is getting more compressed and so there is more and more time between equally spaced samples. Here’s one of my old graphs of the same data, showing the same phenomenon:
Where I think they go wrong is the claim that they can somehow reconstruct, not just the couple thousands of years of temperature that Mann claimed, but nearly a million years of temperature … and that the timelines for the two wouldn’t have errors.
My rule of thumb about these kinds of things is, no error bars … no science.
w.
Other rebuttals are in the works. I will add to this posting as they develop.
Pat Michaels writes to junkscience.com:
I am very unexcited about this. I have always thought that the timing of carbon dioxide changes and warming/cooling is pretty much irrelevant… What is interesting about this latest “finding” is that it demonstrates, yet again, the unfalsifiability of climate change “science”. The standard argument on the ice cores has been that temperature preceding carbon dioxide changes is simply evidence for positive feedback rather than lack of forcing. Now the argument will revert back to the other way around — that CO2 causes all the major pleistocene (which we are still in — see Greenland) climate fluctuations.
About that carbon dioxide–it’s just another attempt to explain the true mystery of climate change, which is why major glaciations ever go away.
My mantra is that “it’s not the heat, it’s the sensitivity”, which is obviously overestimated in climate models, for a variety of reasons that should be obvious.
Tom V. Segalstad Associated Professor of Resource and Environmental Geology, at the
University of Oslo writes:
There are some serious problems with ice cores.
I’ll be surprised if the new Nature paper cites our paper by Jaworowski, Segalstad & Ono (1992): Do glaciers tell a true atmospheric CO2 story? in the professional peer-reviewed Elsevier journal “Science of the total environment”, Vol. 114, pp. 227-284 (1992). The paper is available on my website here: http://www.co2web.info/stoten92.pdf
There’s a follow-up paper (abstract) on the stable isotope temperature measurement technique in ice cores here: http://www.co2web.info/aig.pdf
I checked the references of the Shakun et al paper published today, and the paper Segalstad mentions is not part of the references section. I guess it was too inconvenient to mention.
Wait a second…In this study of the end of the previous glaciation, they are claiming that the Northern Hemisphere ice cap began to melt due to an increase in solar energy caused by a wobble in the Earth’s orbit. So the N.H. is warmed and the melting ice decreases the Earth’s albedo, gradually adding more warmth. The fresh water flows into the North Atlantic and puts the breaks on the Atlantic currents that take tropical warmth to the high northern latitudes, causing the Southern Atlantic to warm. While this would then begin to release CO2 from the oceans, the warmer waters would also be warming the Southern Hemisphere air. The article above does not mention albedo or the immediate impacts of a warming ocean on atmospheric temperatures, but certainly the laws of physics applied then as well as now.
So, in a nutshell, the Northern and Southern Hemispheres are both warming before the CO2 is released. How is that any different than what has been said all along? The temperature in the north is rising, or else the ice would not be melting. The temperature in the south is warming because you can not warm an ocean without warming the atmosphere over it. The paper plainly shows that warming atmospheric temperatures preceded the increasing CO2.
Certainly, once the CO2 begins to increase, it has an impact. So now we are back to the same argument about the climate sensitivity to increasing CO2. The authors claim that the CO2 accounts for ‘much’ of the warming, what ever that means, but they give no evidence to support that claim.
Frankly, I don’t see anything new here, other than wording in the conclusion that is even more ambiguous than usual.
Steven Mosher says:
April 4, 2012 at 1:05 pm
“The only people who deny that C02 will warm the planet are those who fail to understand the experimental evidence.”
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Sorry Steven, that will not wash. Some of us have actually taken the time to conduct empirical experiments into this issue.
I have tried the Tyndall tube experiment and it does indeed work. I have also tried a similar experiment with SW radiation and a black target surface inside the CO2 chamber. I found that just as CO2 has the ability to adsorb and back radiate part of LWIR leaving the target surface it also has the ability to radiate away energy it has acquired through conduction.
I have also checked the ability of incident LWIR to slow the cooling of materials. This does indeed work, and is quite measurable. However it is negligible in the case of water that is free to evaporatively cool. What makes up 71% of Earth’s surface?
Just how powerful is that supposed 300 w/m2 pouring down from the night sky? Take a flat matt black aluminium plate and attach a peltier cooler to the underside. Insulate the base with EPS foam. Cover the upper side with a screen double glazed with IR transparent film. Cool the plate to -10 C, then expose to the night sky. Does the plate heat up or continue to cool after the peltier is switched off? Now try illuminating with 300 w/m2 from a halogen globe.
Is the surface air temperature 33C warmer than it would otherwise be due to GHGs in the atmosphere? Or is the surface air temperature 150 to 190C warmer than it would be at .01 bar because we actually have a surface pressure of 1.0 bar? Take two identical IR transparent containers with identical internal black target surfaces. Regulate the pressure in one container to 1.25 bar. Illuminate both with an identical amount of SW. Which chamber reaches the higher air temperature? Does changing the CO2 content change the result?
I am dismissive of CAGW because I understand the empirical evidence.
Climate Lysenkoism as its finest. Anything goes in Nature and Science as long as it supports the cause.
Ahhh Edouard Bard is a co-author… Bard is a also a anti hero of climategate, when Jouzel called on Jones to help poor Edouard in the Courtillot affair. It is funny to see a pure speculation paper co signed by Bard, published in Nature when in fact all observations are showing Leroux’s work, the climatologist IPSL and Grenoble teams have systematically ganged up against, is being verified as the time passes!
Jouzel and Bard are desperate…
Smokey says:
April 4, 2012 at 11:42 am
Over hundreds of millennia rising temperature always precedes rises in CO2:
http://www.brighton73.freeserve.co.uk/gw/paleo/400000yearslarge.gif
I have several other charts from both hemispheres, all of which show CO2 rises after temperature rises. Either they are all wrong, or Shakun et al. are wrong.
Useful chart – although some more labelling and source info wd be helpful. The earlier comment by George E Smith is important – in your graph, look at the DESCENDING temps post interglacial – the long ragged and protracted falls from interglacial to full glacial. During these unstable downslopes the lag of CO2 behind temperature is at its most obvious.
Why are units measured in “parts per hundred” (pph) i.e. Celsius degrees and units measured in parts per million (ppm) i.e. CO2 concentration shown together on the same Graph-paper? – On the Gore-graph CO2 is enhanced by a factor of 10 000. – No wonder the “general public” think we are doomed!
Morrell- I’m not an expert on this but one good read is:
Richard Alley, Reliability of ice-core science: historical insights, Journal of Glaciology, Vol. 56, No. 200, 2010
Diffusion (in the ice) is a very slow process and there’s been some studies on this, but it’s a small issue. Diffusion occurs in the firn and will smoothe out, for example the seasonal cycle that you in Mauna Loa records, and the bubble trapping in the so-called buuble close-off zone. There’s some other issues that would prevent good atmospheric composition reconstructions (e.g., frequent formation of melt layers and reaction between acidity and carbonate; for this reason CO2 paleo-records are not taken from Greenland but some of them aren’t too bad).
“The melting in the north could have been triggered “because the ice sheets had reached such a size that they had become unstable and were ready to go.” ”
Well. I nominate that as dumbest climate quote of the decade.
The press release above says ” Small changes in the Earth’s orbit around the sun affected the amount of sunlight striking the northern hemisphere, melting ice sheets that covered Canada and Europe.”….. Er.. So it warmed first then?….. But that doesn’t count somehow?
This climate “science” sure is tricky…… or is that trippy.
I think Ferdinand Engelbeen(sp?) has shown pretty convincingly that the rise in CO2 during the start of the interglacial follows Henry’s Law closely — the CO2 rise is simply a result of the warming ocean not able to hold as much CO2 & thus gradually released it to the atmosphere (and then reverses at the start of a new glacial period). Seems pretty simple & clear-cut.
mwhite says:
April 4, 2012 at 11:41 am
Makes a good point:
But furthermore: if initially there is more heat, to melt the northern ice masses, which then causes an warming of the Antarctic, which causes CO2 to rise, which then causes more temps to go up … we are leaving out the continued heating that initiated the whole ball of wax rolling in the first place.
Heat, then, while continuing to heat, CO2, then more heat … which was happening before, during and, I dare say, after the CO2 increase.
So many games, so few research grants!
This whole “CO2 lagged behind the warming” has been one of the foundations for believing there is nothing to worry about . This finding is a major blow to the wall that is the skeptic argument. This is not the removal of one or two bricks, but a major structural failure. In fact I can hear the falling of debris as I write.
Steven Mosher says:
April 4, 2012 at 1:05 pm
The only people who deny that C02 will warm the planet are those who fail to understand the experimental evidence.
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So give the evidence. Give it now. Do not run away. Do not ignore this request. Do not refer to some amorphous ‘it’s in all the text books’ or ‘it is well known’ – DAMN WELL PRODUCE IN ALL ITS DETAIL.
NOW.
Shakun’s own hypothesized account says that warming came first. First there was a Milankovitch warming of the northern hemisphere that melted enough northern ice to shut down the ocean conveyor, then this shutdown caused heat to accumulate in the south, eventually warming the southern oceans enough to release CO2, which is then hypothesized to have induced further warming. How is this at all consistent with his claimed finding that CO2 increase preceded warming? All this northern hemisphere melting and southern ocean warming was supposed to have occurred in the absence of any warming? WTF?
Here is the story as Shakun tells it in his press release, copied from above for handy reference:
After this elaborate story of northern and then southern hemisphere warming leading eventually to the release of CO2 (which is presumed to have further warming effects), the press release states the finding that CO2 precededwarming without any note of the complete contradiction with the story just told:
Their attempt to come up with a story of how CO2 could have preceded warming is an utter failure. Their own story has warming coming first. This is beyond strange. They don’t mention the Younger Dryas, but the only way I can see to make sense of their story at all is as an attempt to account for the Younger Dryas as primarily a northern hemisphere event.
Melting from northern hemisphere warming shuts down the ocean conveyor, refreezing the north and warming the south. That way southern ocean CO2 can be released while the planet on average is still semi-glacial. As an account of the Younger Dryas, this story is at least POSSIBLE, but it still does not imply any significant role for CO2. By hypothesis Milankovitch effects were already strong enough to de-glaciate the north and would presumably do so again when the conveyor started back up. Wouldn’t that start to happen as soon as the north stopped melting? Could take a while, but there is no role for CO2 in it. According to their story–where melting interferes with the conveyor–CO2-induced-warming would only interfere with the restarting of the gyre. CO2 release from the warming oceans could have had a warming effect, but there is still no evidence for it.
Jeremy Shakun et al. is contradicted by this paper. And every year it gets harder to dispute this
This chart shows another view of the ∆T/∆CO2 lag. And CO2 is currently about as low as it has ever been throughout geologic history. If it doubles from here — extremely unlikely — CO2 will still be a tiny trace gas. But the biosphere will benefit, because more CO2 is good for life on earth.
With the rise in CO2 the IPCC’s conjecture says that the planet’s temperature should be rising smartly. It is not. Therefore, the IPCC is as wrong as Shakun et al. They both need to give up their failed conjectures and listen to scientific skeptics; the only climate realists.
Am I am sending this correctly? They’re using CO2 data from ice cores, and comparing it temperature data from other proxies? This despite the fact that temperature data from ice core is when compared to CO2 data from the same core, shows CO2 following temperature change? How can they be sure that the timing from the global temperature sets corresponds to the timing of the ice cores? If the data are both taken from the same ice cores, you have some assurances; however, from the current study you cannot.
Imagine for a moment, that the authors are completely correct.
They have shown that CO2 increases precede temperature rises.
The postulated mechanism involves potentiation of the effect of water in the atmosphere. This causes a positive feedback system that causes runaway warming.
Thus, they should find that atmospheric water levels, thus polar precipitation, and thus the line-shape of depth vs age, should be affected, BEFORE the temperature signal.
Indeed, at the end of each glaciation even we should find that the slopes of depth vs age should track CO2 changes, alas they do not.
Even worse, they know that the rate CO2 fall during the cooling part of the cycle lags temperature changes, now, using this ‘global’ signal, the lag will get worse. The climate sensitivity for CO2 vs Temperature will now have to be quoted for cooling and warming cycles, no longer invariant.
The thing is….. As soon as that extra sunlight (thermal energy) vaporizes the water, it is instantly increasing the only GHG that counts…. H2O in vapor form….. The CO2 that follows after this is inconsequential….. You already have the enhanced feedback loop…. Water vapor responding to the increased heat…. When the oceans heats up enough to release extra CO2, you don’t see any steepening of the warming curve as you would expect if CO2’s effect was significant.
The most telling part is when the thermal energy lessens, straight away the water vapor lessens…. Instead of CO2 maintaining temps, it does nothing to maintain the water vapor and the global system cools, CO2 goes back into solution within the oceans again.
As far as I am concerned the only significant driver is the sun producing more water vapor. CO2’s effect is too small to worry about.
I do think that Chris Colose has touched upon one of the main problems of this whole scenario, and that is Carbon Dioxide is affected by diffusion in the Greenland cores, so is very difficult to use as a proxy for past CO2 changes. Thus, scientists have has to rely fairly heavily upon the much lower resolution Antarctic ice cores. Hence, a huge problem rears its ugly head and that is because of this much lower resolution proxy and the very long time (hundreds of years in some cases) it takes to close or seal off the ice. This leads to the problem I indicated in a post earlier and that is just how much of a lag there was in the closing off the ice. And therefore how does one determine what leads what (CO2 or temperature)?
Myrrh says
“So give the evidence. Give it now. Do not run away. Do not ignore this request. Do not refer to some amorphous ‘it’s in all the text books’ or ‘it is well known’ – DAMN WELL PRODUCE IN ALL ITS DETAIL.”
It’s only been known for over a hundred years, but read this http://en.wikipedia.org/wiki/Greenhouse_effect
All there.
I’m with Mosher (mostly), it is basic physics that CO2 absorbs certain wavelengths of electromagnetic radiation. And that is what is emitted by or bounces off of the earth’s surface.
In the end (without going into the full chain of events) THAT WILL CAUSE WARMING at the surface. There really isn’t much to argue with here (except that the person who dubbed it the ‘greenhouse effect’ has a lot to answer for!).
The significant question is ” how much warming will be caused by a certain level of CO2? “. That is the climate sensitivity question. And that is most assuredly not yet settled.
On the other hand, I didn’t read Mr. Easterbrook’s comment(s) as raising the “trace gas argument”, so I think Mosher was being a bit rough on him there.
mysteryseeker,
Apparently you are willing to throw out the entire peer reviewed literature regarding the CO2 lag, in addition to ice core proxies from both hemispheres [and which are in close agreement], just because the Shakun et al. fatally flawed paper makes some baseless claims in its attempt to turn all the evidence upside down. Mann08 did that with the Tiljander proxy, and he has received universal derision ever since Steve McIntyre exposed his devious shenanigans.
For one example, Caillon’s peer reviewed paper has never been falsified. What makes you think that Shakun’s paper is anything but grant-trolling nonsense? Be specific, now.
All energy in a system must be accounted for in that system. Does that mean that when carbon and oxygen molecules bind there is some new formed energy? Does that mean that when humans exhale carbon dioxide we are sending energy forms from our body?
My understanding says that carbon dioxide is a lagging indicator and not a cause and effect relationship per se. Where is the new energy then coming from?
I am not sure that estimates from proxies at a handful of locations can yell us anything accurately about climate globally. Warmists keep making claims based on the “temperature record”, but very few places had any kind of methodical temperature record prior to the spread of military and commercial aviation, and even those records tend to be clustered in more developed countries.
Okay, here is the highest resolution CO2 and Greenland temperature estimates you can get.
First, the transition out of the last ice age from 22,000 years ago. In this case, the CO2 estimates are all less than 200 years apart (mostly less than 100 years) and the temperature estimates are at less than 25 years apart. Note the large temperature increase at 14,500 years ago.
http://img821.imageshack.us/img821/4267/transliagrnld.png
And then the whole Last Ice Age back to 123,000 years ago. (The resolution of CO2 estimates is not as high over this whole period but there is an estimate at least every few thousand years). Note the Dansgaard Oeschger events – 25 of them.
http://img824.imageshack.us/img824/7671/liagrnld.png
I don’t see CO2 leading anything except that its changes are so small, it cannot have made much difference. It takes 5,000 years to get 0.5 degree out of the CO2 change. More importantly, the northern hemisphere temps are so variable and CO2 is so stable, that there is no way to say there is a cause and effect.