Guest Post by Willis Eschenbach
There’s been a recent paper claiming a long-term correlation between CO2 and sea level, discussed here at WUWT. The paper implies that CO2 controls temperature and thus indirectly sea level. I thought I might follow up the comments on that thread by looking at what the ice core records actually tell us about variations in CO2. There is plenty of dispute about the ice core records, but I don’t want to touch on that here, that’s a separate discussion. Instead, let me take the ice core records as given and see where that leads us. Figure 1 shows the Vostok ice core CO2 and temperature variations.
Figure 1. Temperature and CO2 variations as per the cited data sources. Temperature variations have been divided by 2, as discussed in the text. Graph ends at 1950, most recent CO2 data is from about 2,300 years ago. Maximum temperature during the previous interglacial was about a degree and a half warmer than 1950. Photograph shows that Photo Source http://dxing.at-communication.com/en/ri1anc_vostok-base_antarctica/
These two data traces, unfortunately, are from two different records. The temperature record contains almost ten times the number of data points as the CO2 record (~ 3,100 vs ~360). Accordingly, I have smoothed the temperature data (17-point Gaussian) and then interpolated it to match the dates of the CO2 data points.
In addition, the temperature record is (presumably) a proxy for the temperature of Southern Ocean and environs. This, like all areas near the Poles, tends to experience larger temperature swings than the world as a whole. As a result, I’ve followed the common practice of making a rough estimate of global average temperature changes by dividing the Vostok changes in half.
So what can we learn from these graphs? Well, first off, we can see that this is the coldest interglacial we’ve enjoyed in the last hundreds of thousands of years. I note that humans, and indeed the majority of all species, survived the previous warmer interglacials without thermal meltdown. Next, we can tell from this data whether CO2 is causing the temperature variations, or vice versa.
Let me introduce and discuss five pieces of evidence that all show that the likely direction of the causation is that the temperature is causing the CO2 change, and not the other way around. These are 1) the linearity of the relationship, 2) the agreement with known physics, 3) the lag in the CO2 with respect to temperature, 4) the Granger causality of the relationship, and 5) the disagreement with the IPCC values for climate sensitivity.
The weakest piece of evidence is the linearity of the relationship. The outgassing of the ocean is a linear function of temperature. Looked at the other way, the temperature of the world is said to relate, not linearly to CO2, but to the logarithm of CO2 to the base 2. In the data above, the R^2 (a measure of correlation) between the temperature and the CO2 is 0.68 … but the R^2 between the temperature and the logarithm of CO2, rather than being better as we’d expect if CO2 were actually driving temperature, is marginally worse for the logarithmic relationship (0.67) than the linear. Weak evidence, as noted, but you’d expect the correlation with log CO2 to be better than linear, if not a lot better, if the relationship were actually logarithmic.
Second, the agreement with known physics. Given the data above, I calculate that for every 1°C of temperature increase, CO2 goes up by about 15 ppmv. According to this source, for every 1°C of temperature increase, CO2 goes up by about 12.5 ppmv … so the number I calculate from the data is in rough agreement with known physics.
Third, the lag. Direct correlation of the two datasets is 0.83 (with 1.0 indicating total agreement). The correlation between the two datasets is better (0.86) with a one-point lag, with the change in CO2 lagging the change in temperature. That is to say, first the temperature changes, and then the CO2 changes at some later date. Additionally, correlation is worse (0.79) with the opposite lag (CO2 leading temperature). Again, this is in general agreement with other findings that the changes in CO2 lag the changes in temperature.
Fourth, the Granger causality. You can’t establish a cause statistically, but you can say whether something “Granger-causes” something else. A Granger test establishes whether you have a better chance of predicting variable A if you know variable B. If you do, if knowing B gives you a better handle on A (beyond random chance), we say that B “Granger-causes” A.
Now, there’s an oddity about Granger causation. There are four possibilities for Granger causation with two variables, viz:
1) Variable A doesn’t Granger-cause variable B, and B doesn’t Granger-cause A
2) Variable A Granger-causes variable B, and B doesn’t Granger-cause A
3) Variable A doesn’t Granger-cause variable B, and B Granger-causes A
4) Variable A Granger-causes variable B, and B also Granger-causes A
It is this last one that is an oddity … for example, this last one is true about the CO2 variation versus temperature on a monthly basis. This makes sense, because of the seasonally varying drawdown of CO2 by plant life and the seasonal temperature variations. CO2 levels affect plant life, and plant life also affects CO2 levels, and all of that is in a complex dance with the seasonal temperature changes. So the dual causality is not surprising.
In the current example, however, the results of the Granger test in the case of the Vostok data is that temperature variations Granger-cause changes in CO2, but not the other way around—CO2 doesn’t Granger-cause the temperature.
Finally, the disagreement with the IPCC values for “climate sensitivity”. If we use the data above, and we assume that the temperature actually is a function of the CO2 level, we can calculate the climate sensitivity. This is a notional value for the change in temperature due to a doubling of CO2. When we calculate this from the Vostok data given above, we find that to work, the climate sensitivity would have to be 23°C 7°C per doubling of CO2 (corrected, thanks to commenters) … and not even the most rabid alarmist would believe that.
So those are my five reasons. The correspondence with log(CO2) is slightly worse than that with CO2. The CO2 change is about what we’d expect from oceanic degassing. CO2 lags temperature in the record. Temperature Granger-causes CO2, not the other way round. And (proof by contradiction) IF the CO2 were controlling temperature the climate sensitivity would be seven degrees per doubling, for which there is no evidence.
Now, the standard response from AGW supporters is that the CO2, when it comes along, is some kind of positive feedback that makes the temperature rise more than it would be otherwise. Is this possible? I would say sure, it’s possible … but that we have no evidence that that is the case. In fact, the changes in CO2 at the end of the last ice age argue that there is no such feedback. You can see in Figure 1 that the temperatures rise and then stabilize, while the CO2 keeps on rising. The same is shown in more detail in the Greenland ice core data, where it is clear that the temperature fell slightly while the CO2 continued to rise.
As I said, this does not negate the possibility that CO2 played a small part. Further inquiry into that angle is not encouraging, however. If we assume that the CO2 is giving 3° per doubling of warming per the IPCC hypothesis, then the problem is that raises the rate of thermal outgassing up to 17 ppmv per degree of warming instead of 15 ppmv. This is in the wrong direction, given that the cited value in the literature is lower at 12.5 ppmv
Finally, this is all somewhat sensitive to the assumption that I made early on, which is that the global temperature variation is about half of the variation shown in the Vostok data. However, this is only a question of degree. It does not negate any of the five points listed above.
w.
PS—One final thought. IF we assume that the change in CO2 is due to the temperature change, as my five arguments support, this would indicate that the degassing from temperature changes is far from sufficient to cause the recent rise in CO2. I hold that the recent rise in CO2 is anthropogenic, but others have claimed that it is not from the burning of fossil fuels, that it is (at least in significant part) due to the temperature change.
But my calculations, as well as those in the reference I cited, show that CO2 only goes up by ten or fifteen ppmv for a one-degree temperature rise. As such, this is way too small to explain the rise in atmospheric CO2, which has been on the order of 75 ppmv since 1959.
SOURCES
Willis, the outgassing of water is not a linear function of temperature, although you can treat it as approximately linear in a small range of temperatures. Is such approximation good enough for your argument or do you know something about the oceans that makes CO2 solubility in them more linear than in pure water?
I’m looking at the solubility graph on this page: http://www.sott.net/article/177136-Basic-Geology-Series-CO2-in-the-Atmosphere-and-Ocean
Very interesting, but it all depends on how well the data series can be pinned together. How well can two ice core series be related to each other in time?
Another oft reproduced graph is this one:
http://s691.photobucket.com/albums/vv271/runawaymachine/?action=view¤t=720px-Co2-temperature-plot_svg.png&sort=ascending
While the current CO2 level is highlighted, the current temperature anomaly is not, doubtless because it loiters down around 0.5 (not 5.0, but 0.5) , making it look as if CO2 can vary enormously wuthout having any discernable effect on temperatures.
Thank you Willis,
for showing graphs back to 450,000 years ago to establish a cyclical trend in ice cold and warm. There are many papers that I have read in the Paleo Climatology section of American Geophysical Union (AGU) that support that trend extending back approximately more than 2 million years. The cycles are amazingly consistent: 100,000 years of ice, 15-20,000 years of warmth. Our time is virtually up in this warming period. The question is how to respond to the next change.
Unfortunately, we have Johnny-Come-Lately’s that call themselves scientists of this new realm of “science” called “climate science”. Please excuse the humor, but it appears to me that these individuals have no concept of climate beyond maybe the past fifty years. Recorded history as data means little if anything. . These individuals have no appreciation of this older data set and papers based upon evidentiary observation. Apparently, these well known research papers have escaped their review.
Thank you for sharing some light on this research, so that others may have a glimps of where to start, in trying to understand our climate.
Very nice article (as are most of your posts – I always learn something). Your last point strikes home; regardless of the causality issue, the chart certainly makes one question the forcing argument.
I am new to this, and I was wondering why the recent (100 year) increase in CO2 ppm has been so linear. Can you point me to any references? Thanks.
Not sure we have enough information to say that, really. What I mean is that ocean cools a lot faster than it warms. We were in a pretty cold period during the LIA. If we assume that the ocean contains a lot of CO2 and that cooler water holds more CO2 than warmer water and that one can cool the ocean a lot faster with a change in surface conditions than one can warm it, if we maintained the current surface temperature, it would take about 600-800 years for the ocean to completely give up all the CO2 it absorbed during the LIA. And that assumes that temperatures at the surface stay flat for 600 to 800 years (which they won’t).
It takes about 800 years to ventilate the ocean which means it takes about 800 years for most of the water to touch the surface and exchange gas with the atmosphere. Cooling the ocean works fast for a couple of reasons but mostly because that works with convection. We also have more brine rejection from sea ice that sends a lot of very cold, very salty water to the bottom of the ocean in a hurry. If you warm the surface, the water wants to stay on the surface. It is hard to warm the abyssal deep from applying heat to the surface. You have to wait until the water circulates to the surface for the heat to be applied. It is really easy to cool the abyssal deep by cooling the surface. So the ocean takes up CO2 faster than it gives it back.
Looking at old plant stoma, it has been suggested that CO2 content during the MWP was possibly at or a little higher than today’s levels. (remember this? http://wattsupwiththat.com/2010/12/26/co2-ice-cores-vs-plant-stomata/ )
So there is another reason to believe that while humans certainly ARE adding CO2 to the atmosphere, it isn’t the primary component (we already know it isn’t the primary component because the atmosphere is accumulating CO2 at a much faster rate than humans add each year) because while human emissions have been rising nearly exponentially, atmospheric CO2 has been rising linearly and that rate of rise did not change when global human CO2 emissions fell in absolute terms (tons of CO2 emitted to atmosphere fell in 2009, rate of increase of atmospheric CO2 unchanged).
It is going to take some 600+ more years for the ocean to give back all the CO2 it took up during the LIA.
Good analysis Willis. I also look to the last interglacial where temperature peaked and dropped 2°C with CO2 barely changing over 15-20K years.
Nice paper.
Looks like the links to the Vostok temp and CO2 data were flipped.
[Thanks, fixed. -w.]
Nice Willis. Some good food for thought……
Crossposting from http://wattsupwiththat.com/2013/01/03/paleo-sea-level-and-co2/#comments
I have not read the paper yet, but before I do it may be useful to point out some constraints. The first one being resolution. Some of the better proxies include Greenland ice, which gets us back something in the range of ~130kya (~130,000 years ago), and speleothem (stalactite/stalagmite) and flowstone deposits, which arguably can get us back a few million years or so. Beyond that are various isotopes isolated from ostracods etc. in deep sea sediment cores. Some studies for Greenland ice core studies lay fairly credible claim to be able to attain as good as decadal resolution, but more towards the upper cores, not so much the lower sections, where slip planes and other things can complicate matters considerably. There are others, I just decided not to go into them.
From the Greenland cores there are two really important considerations; (1) ~130k DOES NOT get us back to the start of the last interglacial, from which one can infer that the Greenland sheet may have completely melted away during the inception and early millenia of the Eemian, and (2) the better resolution of Greenland ice (as opposed to Antarctic ice) has repeatedly shown that temperature changes precede CO2 changes.
According to Mudelsee (2001) (http://manfredmudelsee.com/publ/pdf/The_phase_relations_among_atmospheric_CO2_content_temperature_and_global_ice_volume_over_the_past_420_ka.pdf) from the abstract:
“Over the full 420 ka of the Vostok record, CO2 variations lag behind atmospheric temperature changes in the Southern Hemisphere by 1.3 +/- 1.0 ka, and lead over global ice-volume variations by 2.7 +/- 1.3 ka.”
For reference, this was one of the definitive papers establishing which came first, and it was published some 4 years before Gore’s “Inconvenient Truth” inversion. Cause and effect unraveled 12 years ago, why this is even an issue now is really quite beyond me.
Beyond the onset of northern hemisphere glaciations, some ~2.8Mya, which is some 2 or so million years older than we can really guess which came first, it becomes sort of a ‘silly-buggers’ game.
Others here have already pointed out that coincidence is not causation. Still others have expanded on the degree to which CO2 is better absorbed by cold water than warm. It is somewhat difficult to imagine a world in which sea levels were much higher than today if it was not indeed warmer. What may not have been considered is the increased areal extent of littorals resultant from a sea level increase of +65m (~213 feet). Plot the areas covered up to +65m on coastlines worldwide and see what percent sea surface is increased over present. I know I have seen several papers which have considered this, but I am just not going to take the time this evening to look that up. But it’s big.
So more surface area to degas, if that means anything here.
As so often is the case, seemingly especially in this lopsided debate, is a phenomena best illustrated by Ziggy. One of my all time favorite cartoons is of Ziggy standing before three vending machines, scratching his head. The first vending machine says “The Truth – 25c”. The middle vending machine says “The Whole Truth – 50c”. and the last machine is entitled “The Truth, The Whole Truth, and Nothing But The Truth – $1.00”. The numbers might be memory faded, but you get the point (I hope).
In terms of “The Truth” this “debate” is about AGW. But “The Whole Truth” might skew closer to that it is about GW, AGW and GC (global cooling), in other words what is our attribution “signal” relative to normal climate “noise”, or signal to noise ratio.
But what would a buck get us from the climate vending machine? What is “The Truth, The Whole Truth, and nothing but the Truth?” That would include the univers of what we do know and what remains to be known about climate. At a minimum it would necessarily include the miserable state the 4 global data sets are in, the various methods and means of which this record consists, loss of ~70% of reporting stations (predominately high latitude, high altitude and rural) post 1990, and what resides in my mind at least as pure horror at the state of the surface stations Anthony et al have and are documenting. To this we must necessarily add when we live, about half a precession cycle since the more or less agreed beginning of the Holocene (termination of the YD event). Five of the past six such interglacials have each lasted about half a precession cycle……
And the ends of the “extreme” interglacials (those that have achieved at least our sea level, the highstands of which continue to be documented), provide a chilling and robust record of the climate extremes which appear to occasion their ends. An analysis of some of this may be found here http://wattsupwiththat.com/2012/03/16/the-end-holocene-or-how-to-make-out-like-a-madoff-climate-change-insurer/
My initial impression is that this paper, only having read what is here, may fall at the “blue light special” (heavily discounted) end of the 25c The Truth. Meaning to me that I may learn a thing or two by reading it and vetting the cited papers critically. With so much end extreme interglacial normal climate “noise” it is seems like such a LEAP to matheMANNically manufacture CO2 numerical/Nutticelli attribution anywhere near close enough to allow calculation of the ideal gas law concentration.
I am just not so sure that any correlation drawn prior to the closing of the Panama Seaway (some ~5Mya) is oceanic circulation comparable to the present except in the grossest terms.
“The onset of the LEAP occurred within less than two decade, demonstrating the existence of a sharp threshold, which must be near 416Wm-2, which is the 65N July insolation for 118 kyr BP (ref. 9). This value is only slightly below today’s value of 428Wm-2. Insolation will remain at this level slightly above the inception for the next 4,000 years before it then increases again.”
http://einstein.iec.cat/jellebot/documents/articles/Phis.Lett.A_2007.pdf
Repeating myself:
So be ever thoughtful of both facts and predictions before leaping to a conclusion. It was in fact a LEAP that terminated the last interglacial, the cold Late Eemian Aridity Pulse which lasted 468 years and ended with a precipitous drop into the Wisconsin ice age. And yes, we were indeed there. We had been on the stage as our stone-age selves about the same length of time during that interglacial that our civilizations have been during this one.
From the geological perspective, I’ve always argued that there is another qualitative signal that CO2 cannot be a strong factor. That is, if T is assumed to be driven by CO2, then why does T always change direction (sign of trend) when CO2 should be resisting change the most?
T always begins to decline just when CO2 is at its highest level
T always begins to rise just when CO2 is at its lowest level.
I think that the same signature over the last 4 glacial-interglacial cycles is ample evidence that a “strong CO2 model” cannot be true.
The lag also indicates that CO2 responds to T (not vice versa), but I think the change-of-direction is stronger evidence of cause-effect.
It’s hard to sustain the notion of “tipping points” when the evidence shows the exact opposite. Climate mostly reflects negative feedbacks (conservative conditions).
Some good points.
But a graph so zoomed out as figure 1 should be posted with a more zoomed-in version too. For instance, the following, while somewhat like the GISP 2 plot I often post, is for Vostok data specifically to match the Vostok subject of this article:
http://c3headlines.typepad.com/.a/6a010536b58035970c01348128c941970c-pi
Without a graph so zoomed out as to make a millenium be close to a pixel, without century-scale info in the data being hidden, CO2 being the prime driver of temperature becomes blatantly absurd, as opposed to the oceans slowly warming or cooler (slower than the surface), with the temperature affecting CO2 release or absorption as this article notes.
As often so, a trick is asking what the CAGW movement is very careful to never, ever, ever publicly show, as that is the best of all.
Gene Selkov says:
January 3, 2013 at 7:52 pm
Thanks, Gene. We’re only talking ± 6°C temperature swing, so the linear approximation will be quite close.
All the best,
w.
A full mathematical work-up of the relationship between CO2 solubility in water and temperature in the Vostok record is here, http://www.rocketscientistsjournal.com/2006/10/co2_acquittal.html, with the conclusion that “Throughout the past 420 millennia, comprising four interglacial periods, the Vostok record of atmospheric carbon dioxide concentration is imprinted with, and fully characterized by, the physics of the solubility of CO2 in water, along with the lag in the deep ocean circulation.”
since hansen predicted the lag of versus temperature in 1990, folks might want to watch this
Steven Mosher,
Dwell on this chart for a few minutes. The cause and effect is clear. ∆T causes ∆CO2; not vice-versa.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CEwQFjAC&url=http%3A%2F%2Ficebubbles.ucsd.edu%2FPublications%2FCaillonTermIII.pdf&ei=3mrmUMDiHOGliQLWpYGgAw&usg=AFQjCNHE01OAm5j02qEYRdoPrSPEi_H6aA&bvm=bv.1355534169,d.cGE
Steven Mosher says:
January 3, 2013 at 9:26 pm
—————————
At about 7:10 in the instructive video, the narrator said “denier” twice in two sentences.
Propaganda is only that, nothing more.
So, here we are.
Well, with every passing year we build up more and more empirical evidence. We will find out soon enough. We have been watching CO2 vs Temperature for a while. What gets me is that from 1910 to about 1940 we saw nearly identical temperature increase over nearly an identical span of time at a point when human CO2 emissions could not possibly have been a factor.
All we need now is a cooling trend and it blows the entire thing right out of the water.
“The outgassing of the ocean is a linear function of temperature.”
Its a solibility product issue. The relative concentrations in the air and water also affect the rate.
. . . but to the logarithm of CO2 to the base 2.
Is it not the natural logarithm (ln; base e) and not the binary logarithm (log2 n)?
Steven Mosher says:
January 3, 2013 at 9:26 pm
since hansen predicted the lag of versus temperature in 1990, folks might want to watch this
Nice Cartoon, Steven:
~”The climate denial industry”…”contradicts the overwhelming mainstream consensus”…and “the very study that climate deniers hope you won’t read”…”Yabba-dabba-dooo!”
Steven Mosher says:
January 3, 2013 at 9:26 pm
The problem here is, Steve, that if CO2 concentrations precede temperature changes, and that if these changes occur naturally up to at the very least +6m above present sea levels, then the 2007 AR4 “worst case” rise in MSL by 2100 clocks in at just 10% of what happened at the end of the last extreme interglacial, MIS-5e.
There were no SUVs for, at least, well before the industrial revolution. So the problem becomes a best anthropogenic (currently), +0.59m estimate of sea level by 2100 vs. a low estimate of +6.0m at the end of the second thermal pulse at the very end of the last interglacial.
OK, I’ll give you +.01m to make the math easy.
So, what you are telling me is that I am supposed to be concerned of a possible anthropologically derived sea level rise (signal) 1/10th the range of the lowest estimate of the last interglacial’s lowest estimate of sea level rise at the second thermal pulse at yet another half-precessional old extreme interglacial.
Your anthropogenic signal, is at best, 10% of the most recent end-extreme-interglacial noise.
Right. I am righteously scared.
But wait, if you call now, we will throw in the last time gaia was at an eccentricity minimum, that would be that 6th interglacial back, which lasted from just 1.5 to 2 whole precession cycles.
Not to worry, that little booger might have achieved a single thermal pulse, right at its very end, scoring a mere +21.3m rise over present MSL,
http://si-pddr.si.edu/jspui/bitstream/10088/7516/1/vz_Olson_and_hearty_a_sustained_21m_sea-level_highstand_during_mis_1.pdf
You’re kidding, right?
Please enlighten me as to why I should be reasonably concerned with an anthropogenic signal, sea-level wise, which is at best 10% of the most recent end extreme interglacial climate “noise”, and which, at worst, is 2.8% of the possible +21.3m MSL which may have been achieved the last time we were at an eccentricity minimum…….
OK, I am duly scared. But not so much
“that would be that 6th interglacial back”
Oops! That would be that oddball “five out of the last six Interglacials” that did not strictly conform to the half-precessional clock, post Mid-Pleistocene Transition.
That would be MIS-11…….
geologyjim says:
January 3, 2013 at 8:52 pm
T always begins to decline just when CO2 is at its highest level
T always begins to rise just when CO2 is at its lowest level.
=========
There is only one conclusion possible. Adding CO2 to the atmosphere causes cooling and reducing CO2 causes warming.
The mechanism is the partial pressure of gas law. Adding CO2 displaces H2O. Since H2O is a stronger GHG than CO2, the net effect of adding CO2 is cooling. The ice cores make this clear.
crosspatch says:
January 3, 2013 at 8:16 pm
What I mean is that ocean cools a lot faster than it warms.
========
Agrees, good analysis. Warm water doesn’t sink, while cold water does. Therefore the mixing rate rises as temperature drops. Thus, you can’t heat the deep oceans from above, but you can cool them.
Mosh you are better than this, c’mon.
Caveat emptor. You might want to be careful relying too much on the timing and amplitude of ice signals. Siegenthaler and others covered this ground pretty well already, but I like the 5 points.
Mosher: Do you think that video is more than propaganda? Again letting someone else influence you rather than you explain why you think CO2 was anything more than a short lived correlation? Hansen et all say that the recent warming was 90% certainly caused by CO2. Yes – CO2 went up and temperatures went up. But what does Hansen say now that CO2 continues to go up and correlation stoppedis this period not important, but the last 30 year period was important?
Jeeze, Steve–Did you study the graph D. Boehm posted for your benefit? Do you know how to tell which came first–temperature increase or CO2 increase? Or the converse–temperature decline or CO2 decline?
Is your “belief system” so inculcated in your soul that logical thought and rational deduction are impossible? If so, you are no scientist, but simply a cult follower.
Perhaps Ayn Rand said it best in Atlas Shurgged when she had John Galt say (p. 1059):
“Learn to distinguish the difference between errors of knowledge and breaches of morality. An error of knowledge is not a moral flaw, provided you are willing to correct it; only a mystic would judge human beings by the standard of an impossible, automatic omniscience. But a breach of morality is the conscious choice of an action you know to be evil, or a willful evasion of knowledge, a suspension of sight and of thought. That which you do not know, is not a moral charge against you; but that which you refuse to know, is an account of infamy growing in your soul. Make every allowance for errors of knowledge; do not forgive or accept any breach of morality. Give the benefit of the doubt to those who seek to know but treat as potential killers those specimens of insolent depravity who make demands upon you, announcing that they have and seek no reasons, proclaiming, as a license, that they ‘just feel it’–or those who reject an irrefutable argument by saying ‘It’s only logic’ which means: ‘It’s only reality.’ The only realm opposed to reality is the realm and premise of death.
@ Steven Mosher
Projection much? That was propaganda.
Note the one blurb about the Sun with no supporting evidence?
Note the “denier” label in like every other sentence?
Note the “Professional Climate Deniers” idiocy?
Note the Hansen hero worship?
Note the “amplification” meme that you and Lief are critical of wrt solar?
Come on man, snap out of it! Is there no cure for SkS Syndrome?
You’re listening to activists like they’re scientists:
http://climatecrocks.com/about/
“Peter Sinclair is a long time advocate of environmental awareness and energy alternatives. An award winning graphic artist, illustrator, and animator”
I wonder if asked to sign a petition to ban dihydrogen monoxide what he’d do.
More to the point if he promoted signing it would you?
Professor Hayden at the ICCC7 reported a very striking 99% correlation between sea surface temperature anomalies and atmospheric log(CO2 ratio). He stressed that this was a correlation, not a time series, and came to the conclusion that temperature is likely to be the main driver of CO2 and not the other way around. I have a hard time reconciling this 99% correlation with the fact that human emissions must have added some amount of CO2 to the atmosphere. The only way the correlation could remain 99% (that I can think of) is, if human contribution were a constant, which is plainly not the case. Can anybody shed some light on this for me?
http://climateconferences.heartland.org/howard-hayden-iccc7/
And similarly this one:
http://icecap.us/images/uploads/Globalclimatechangehasnaturalcauses.pdf
So are you saying that you don’t believe that an increase in co2 in the atmosphere will increase the earths temperature?
The video that Steven Mosher links to, mentions the movie The Great Global Warming Swindle, which was debunking the alarmist claim that CO2 was a climate DRIVER. The video explains that the argument is that CO2 is, rather, an “amplifier”. That’s not the argument. Sceptics appreciate the amplifier claim and the issue is whether the amplifier is a significant player in climate or not. So why link to an argument that assumes sceptics are (a) stupid and (b) knocks down a strawman?
CAGW is Granger-dead.
Henry Clark says:
January 3, 2013 at 8:53 pm
You’re busting me because my graph doesn’t look like your graph? It doesn’t show the details you say that you are interested in?
Well, since in this topic I could care less about the details, and I’m just interested in the overall view, I use an overview graph. So sue me.
Certainly, when you write a post, you are free to use the specific graphs that you judge will best elucidate the points you wish to make.
As am I …
Best regards,
w.
Possibly the strongest indication of whether A drives B or B drives A; is that the lag is much greater during the cooling periods than it is during the warming periods. During warming periods CO2 will be outgassed from whatever part of the ocean profile that exceeds the temperature at which the existing CO2 concentration can stay in solution. However during the cooling periods, CO2 can only go into solution at the atmosphere, ocean surface interface, irrespective of the ocean temperature.profile. This would lead to a much greater lag during cooling should temperature be the driver; and this is the observed evidence. If Co2 drives temperature than this would not be the case.
In Wills article he says:-
“because of the seasonally varying drawdown of CO2 by plant life and the seasonal temperature variations. CO2 levels affect plant life, and plant life also affects CO2 levels, ”
Temperature certainly changes the rate of respiration – photosynthesis – not so much – otherwise the Yamal trees and the hockey stick would not be controversial.
Weak evidence, as noted, but you’d expect the correlation with log CO2 to be better than linear, if not a lot better, if the relationship were actually logarithmic.
——–
Ignoring that the equilibrium relationship between CO2 partitioned between atmosphere and ocean is not linear, but logarithmic.
Most physical and chemical processes that depend on temperature are logarithmic with temperature. Not good if temps are going up.
John F. Hultquist says:
. . . but to the logarithm of CO2 to the base 2.
Is it not the natural logarithm (ln; base e) and not the binary logarithm (log2 n)?
It’s the same thing. I was going to point out that Willis was making an unnecessary detail in specifying log2. A log relationship is a log relationship , whatever the base. The only difference is a scaling factor: the logA(B) eg log(2.0) or log2(10.0) or ln(10.0) etc .
It would have been sufficient (and perhaps clearer) if Willis had just said ‘logrithmic’.
Thanks to Willis for yet another informative article. Especially in covering the question of outgassing.
Steven Mosher says:
January 3, 2013 at 9:26 pm
Or they might not want to watch it. Let me give people the digested version of the video you link to. First, it is viscerally unpleasant, with lots of “deniers” and well funded skeptics and the like. Next, it contains lots of cutesie tricks, cartoons and bits from movies, that mark it for the meretricious trash that it is, and aren’t funny in the bargain.
More to the point, his argument is that CO2 is necessary to explain the ice ages. He doesn’t establish that, he asserts it. In support of his assertion, he cites only one paper, called “Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III“.
He refers triumphantly to the following section in the paper, which says:
Note that this statement does nothing to support the assertion that CO2 is necessary to explain the ice ages. It does nothing to support the idea that CO2 plays a “key role”.
All it says is that the new finding, that changes in temperature lead changes in CO2 by 800 ± 200 years, is not inconsistent with the assertions. It provides no supportive evidence for the assertions. It just says, we can’t rule them out.
But the guy in the video thinks he’s found the Holy Grail. He thinks he has the scientific proof that CO2 is required to explain the ice ages. Unfortunately, you can read it for yourself—the paper said nothing of the sort. All he has is a statement that the new findings don’t rule out the hypothesis. It does nothing to support it.
Man, what a waste of time. One saving grace, though. The inclusion of the cartoons wasn’t as inappropriate as I thought at first, given the childish nature of the scientific claims. After hearing the claims, the cartoons fit right in. That whole extravapalooza was a waste of electrons.
w.
PS—In the paragraph above, there is a cryptic reference to how the “CO2 increase clearly precedes the Northern Hemisphere deglaciation (Fig. 3)”. However, I see no such thing in Fig. 3, which shows the rise in CO2 and CH4 (as a proxy for NH deglaciation) occurring pretty much simultaneously. Next, remember that the temperature rise would of necessity precede and be the cause of the deglaciation, since the ice sheets would respond only slowly to increased summer insolation. They would not melt instantaneously, so deglaciation would necessarily lag temperature rise by some years. Since the deglaciation and CO2 rise are contemporaneous, we can conclude that the NH temperature rise must have preceded the CO2 rise, and not the other way around as they claim.
“CO2 only goes up by ten or fifteen ppmv for a one-degree temperature rise” that might apply if ocean and air temperature was constant around the globe. Various areas of the ocean at different times of the year absorb, as other areas desorb, to a total of almost 20 times man’s CO2 output. A slight imbalance might be sufficient to account for recent increases.
I also find the claims that ice cores trap an exact representation of the air at the time the core is dated, extremely dubious. Beck and Jaworowski have been dismissed too easily.
Steven Mosher says:
“since hansen predicted the lag of versus temperature in 1990, folks might want to watch this”
I clicked because I was interested in what Hansen may have “predicited”. I got about 10s into it and binned it when it became clear it was smart-arsed propaganda not information.
If you have a link that tells us something about Hansen’s lag (I presume this is his “pipeline” hypothesis) in a factual way that may be of interest.
Willis
Nice article.
I think that co2 outgasses at the rate of 6ppm per 1 degree C temperature rise of the ocean. So is it the oceanic temperature we need to be most concerned about? That will vary according to the ocean temperature gradient in as much water is not at all well mixed and so some strata will be warm whilst other parts will be cool. Equally temperatures vary according to the geographic area.
I was most struck by the scientific reports from the arctic in the 1940’s that SST’s in many parts of the Arctic were up to 10C warmer than measured by Nansen fifty years earlier. There were also some very high readings taken of co2 in the greenland area by various scientists at that time that showed that CO2 concentration was very similar to today.
I make no conclusions about any of this as co2 readings made in the relatively recent-pre mauna loa era-are regularly discounted.
tonyb
I am inclined to think that this is another article somewhat poverty stricken in understanding feedback, when the climate system can be subject to different driving forces at different times.
Consider for example a feedback stabilized dc power supply. When the input supply changes negative feedback keeps the output constant. When the output load changes the negative feedback keeps the output constant. So the power supply can be subject to multiple forcings either singly or together with varying amounts.
The same applies to the climate with multiple positive and negative feedbacks operating on different timescales.
Both external changes to CO2 and solar insolation can affect temperature and these both can affect the amount of CO2. To varying degrees at different times and simultaneously.
Willis: “PS—In the paragraph above, there is a cryptic reference to how the “CO2 increase clearly precedes the Northern Hemisphere deglaciation (Fig. 3)”. However, I see no such thing in Fig. 3, which shows the rise in CO2 and CH4 (as a proxy for NH deglaciation) occurring pretty much simultaneously. Next, remember that the temperature rise would of necessity precede and be the cause of the deglaciation, since the ice sheets would respond only slowly to increased summer insolation. They would not melt instantaneously, so deglaciation would necessarily lag temperature rise by some years. Since the deglaciation and CO2 rise are contemporaneous, we can conclude that the NH temperature rise must have preceded the CO2 rise, and not the other way around as they claim.”
Thanks for parsing that for me Willis, Probably saved me half an hour pouring over details to find out what dubious Fig3 claim was all about.
Having debated this issue with British Antarctic Survey scientists and found astonishingly that they had no evidence for the hypothesis that CO2 amplifies the orbital-induced warming once it has begun — they were left lamely saying that the data “is entirely consistent with” that hypothesis — I have to agree with Willis’s characterisation of the very weak video above: it amplified rather than damped my doubts about that hypothesis. Ever Since Gore’s film, the attempt to link ice ages to CO2 has been one of the most egregious examples of confusing cause with effect. It is time that polar scientists were brave enough to admit it.
Thanks, Willis, for a superb essay.
If the CO2 is driving the temperature, what is then increasing and decreasing the level of CO2?
Assuming (knowing) that more CO2 improves the plant grows and the plants would use more CO2, then I think we have a Predator-Prey Relationships.
Assuming that the CO2 drives the temperature, then the plants would grow even better and this would then remove even more CO2 from the air.
The argument for me is that I haven’t seen any credible explanation for CO2 to go up for a time frame of estimated 10% and then go down to a low level for a time frame of estimated 90%.
What’s about the Daisyworld simulation, which is a self regulating system? The white Daisies have a negative feedback and the black Daisies have a positive feedback. This means they will balance the temperature in the end.
As long as we can’t explain both direction, increase and decrease, of CO2 on its own we have no explanation at all for the past. How could we than predict the future?
My conclusion is that there must be an external source. Someone is playing with something like a dimmer. Who could that be. Don’t tell me it is the sun. 😉
Professor. Dr. Mojib Latif, German meteorologist and oceanographer, had said on German TV “This is obviously a lie, if it is claimed that we do not consider the sun. There is no climate model that the sun is not taken into account. I mean we’re not idiots. This will somehow give the impression as if we are the biggest idiot ever.”. I would never say that they are the BIGGEST idiots ever. You can top anything that was before.
/joke on/ Some comedian said that we have not investigated the moon energy. How much energy is used by the moon to make it dark? ;-))
Willis says: “Certainly, when you write a post, you are free to use the specific graphs that you judge will best elucidate the points you wish to make.
“As am I …”
Well said. In fact, many times, if not presented as the author wishes, a graph will lead to off-topic discussions, which always detract from a thread.
Willis, nice summary. Indeed the change of CO2 after temperature changes is near-linear, where CO2 lags some 800 years. That ratio doesn’t change over the past 800 kyears (including Epica Dome C, which shows the same CO2 and temperature changes), which shows that there is little CO2 migration in the ice cores over that time span, or the ratio should fade away each interglacial back in time.
A few additions:
– While coastal ice cores reflect the temperatures of the nearby Southern Ocean (via dD and d18O proxies), the deep inland, high altitude, ice cores of Vostok and Epica Dome C reflect the ocean temperatures for near the whole SH. These are less variable than Southern Ocean alone or the whole NH, where ice sheets did cover large parts of land during most of the time. But the Greenland ice sheet temperature record shows a similar trend over the glacial-interglacial transition, be it with much larger swings, as that mainly reflects the North Atlantic seawater temperature:
http://www.climatedata.info/Proxy/Proxy/icecores.html
That means that the CO2-temperature ratio is probably less than 15 ppmv/°C. Vostok shows 8 ppmv/°C and is taken as rather globally representative.
– 12.5 ppmv/°C is the solubility curve of CO2 in seawater (other sources give 16 ppmv/°C), but at higher temperatures, land plants in general sequester more CO2 in more permanent way and more land area is occupied by plants, reducing the CO2 levels with increased temperatures. That too reduces the ratio of CO2 to temperature.
– An interesting part of the Vostok record is the end of the previous interglacial, the Eemian: while CO2 and temperature go up in parallel, temperatures go down while CO2 levels remain high. At the moment that the temperature is again at a new minimum (and ice sheet growth at a maximum). CO2 starts to go down. The 40 ppmv drop in CO2 level has no observable effect on the temperature record… See:
http://www.ferdinand-engelbeen.be/klimaat/eemian.html
Dr Burns says:
“CO2 only goes up by ten or fifteen ppmv for a one-degree temperature rise” that might apply if ocean and air temperature was constant around the globe. Various areas of the ocean at different times of the year absorb, as other areas desorb, to a total of almost 20 times man’s CO2 output. A slight imbalance might be sufficient to account for recent increases.
Very good point. Too much global averaging going on. This is particularly important when dealing with what is apparently a T^5 relationship. Average global temp may be a fair indication in the presence of a linear relationship. If it’s T^5 it mostly likely needs to be broken down to at least regional average temp.
While Willis’ linear approx may be good enough for rough estimate with small variations, with ampified warming/cooling at the poles where cold waters will be providing a CO2 sink the effect could be much greater.
I have not thought through how this would affect his arguments or conclusions, maybe Willis can comment on that.
Willis:
Thankyou for your very fine article. Even by the high standards of your articles, it is of exceptional quality.
I concur with everything in your article but I write to dispute a conclusion in your Post Script that says
Please note that I don’t know what has caused the recent increase to atmospheric CO2 concentration, but I want to know. And anybody who thinks they know is mistaken because available data permits either an anthropogenic or a natural cause to be attributed (ref. Rorsch A, Courtney RS & Thoenes D, ‘The Interaction of Climate Change and the Carbon Dioxide Cycle’ E&E v16no2 (2005) ).
The Vostock ice core data cannot resolve the issue of what has caused the recent increase to atmospheric CO2 concentration because its temporal resolution is too low. Hence, your calculations (which assess that data) are not a relevant consideration to the issue. I explain this as follows.
Ice cores “capture” CO2 because falling snow solidifies to form the solid ice. The solidification takes decades. During those decades the ice exists as ‘fern’ with open porosity. Importantly, this does not affect the analysis in your article but it is relevant to your post script.
The fern takes several years to solidify to form solid ice which ‘traps’ the air containing CO2. The IPCC suggests the solidification takes 83 years and David Middleton suggests 30-40 years in an article on WUWT
http://wattsupwiththat.com/2012/12/07/a-brief-history-of-atmospheric-carbon-dioxide-record-breaking/
The air and its CO2 will be ‘smeared’ throughout the fern prior to the fern becoming solid ice. This ‘smearing’ is induced by diffusion and physical mixing of the air entrained in the fern. Atmospheric pressure varies with the weather, and the pressure variations will act to expand and contract the entrained air to physically mix air entrained in the fern.
The effect of the ‘smearing’ smooths the observed time series of atmospheric CO2 obtained from the ice core. The smearing is similar to conduct of a running mean on CO2 measurement data from ice which solidified in each single year.
The smoothing is severe.
If the IPCC is right that solidification takes 83 years then the Mauna Loa data cannot be compared to the Vostock ice core data: the measurements of atmospheric CO2 at Mauna Loa have only been conducted for the 55 years since 1958. And if Middleton’s minimum closure time estimate of 30 years is correct then fluctuations similar to the rise in the Mauna Loa data would be more than halved in the ice core data.
Of course, the smoothing would not overcome the order-of-magnitude difference which you mention in your PS. However, that difference assumes that temperature is the only reason for a change to the equilibrium of CO2 concentration between ocean and air. Beck’s data suggests that short-term (i.e. less than 40 years) ‘spikes’ in atmospheric CO2 concentration may have happened in the recent past (e.g. 410 ppmv around 1940) and the fluctuations are not always directly related to temperature: see
http://www.bing.com/search?q=Beck+CO2&form=TSHMHP&mkt=en-gb&qs=n&sk=&pc=MATB&x=115&y=19
Such short-term variations would not be discernible in the smoothed ice core data. And there are possible explanations for them. As example, I provide one such explanation.
CO2 is in various compartments of the carbon cycle system, and it is exchanged between them. Almost all of the CO2 is in the deep oceans. Much is in the upper ocean surface layer. Much is in the biosphere. Some is in the atmosphere. etc..
The equilibrium state of the carbon cycle system defines the stable distribution of CO2 among the compartments of the system. And at any moment the system is adjusting towards that stable distribution. But the equilibrium state is not a constant: it varies at all time scales.
Any change to the equilibrium state of the carbon cycle system induces a change to the amount of CO2 in the atmosphere. Indeed, this is seen as the ‘seasonal variation’ in the Mauna Loa data. However, some of the mechanisms for exchange between the compartments have rate constants of years and decades. Hence, it takes decades for the system to adjust to an altered equilibrium state.
The observed increase of atmospheric CO2 over recent decades could be an effect of such a change to the equilibrium state. If so, then the cause of the change is not known.
One such unknown variable is volcanic emission of sulphur ions below the sea decades or centuries ago.
The thermohaline circulation carries ocean water through the deeps for centuries before those waters return to ocean surface. The water acquires sulphur ions as it passes undersea volcanoes and it carries that sulphur with it to the ocean surface layer decades or centuries later. The resulting change to sulphur in the ocean surface layer alters the pH of the layer.
An alteration of ocean surface layer pH alters the equilibrium concentration of atmospheric CO2.
A reduction to surface layer pH of only 0.1 (which is much too small to be detectable) would induce more than all the change to atmospheric CO2 concentration of 290 ppmv to ~400 ppmv which has happened since before the industrial revolution.
I don’t know if this volcanic effect has happened, and I doubt that it has. But it demonstrates how changed equilibrium conditions could have had the observed recent effect on atmospheric CO2 concentration whether or not there was a change in temperature and whether or not the anthropogenic CO2 emission existed.
Of course, none of this detracts from the analysis in your fine article: it is only relevant to your post script and its stated assumption.
Richard
We should be thinking of Vegetation as playing a role in the CO2-feedback on temperature.
The more Carbon that is cycling through plants each year, the more Carbon and CO2 that will be cycling through the atmosphere each year. Therefore, the more vegetation, the more CO2 in the atmosphere. The warmer and wetter it is, the more vegetation there will be and thus, the circle is completed. In addition, the mix of vegetation plays a role as well.
Right now, more than half of the Carbon cycle is from Vegetation. During the ice ages, C3 bushes and trees died back considerably and most of the land surface was composed of grassland, desert, tundra and ice. Less C3 plants, less Carbon cycling through the system each year.
C4 grasses are actually a very efficient sink of Carbon into soils. So more grass, less CO2. [C4 grasses also evolved between 32 and 24 million years ago. By coincidence, there was also two step-changes downward in the CO2 content in the atmosphere at 32 and 24 million years ago. CO2 went from 1,400 ppm down to 800 ppm at 32 Mya and down to 270 ppm at 24 Mya ].
I’m just guessing, but the CO2-feedback on temperature is probably about half and half, oceans and vegetation/soils.
This 800 year lag between temperature and co2 rise only happens as a ‘trigger’ to end the last ice age, due to orbital forcing. And then as co2 becomes a forcing factor to temperature it becomes the largest influence on temperature to end the ice age Do the Vostock cores not prove this?
crosspatch says:
January 3, 2013 at 8:16 pm
it would take about 600-800 years for the ocean to completely give up all the CO2 it absorbed during the LIA.
As the quantity out of the air absorbed by the oceans during the LIA is negligible compared to the total amount of carbon in the deep oceans, that hardly matters. During the LIA, the atmosphere had some 6 ppmv less CO2 than during the MWP. That is about 12 GtC less CO2. The deep oceans contain some 56,000 GtC… Only temperature matters in this case.
Dr Burns says:
January 4, 2013 at 2:00 am
Various areas of the ocean at different times of the year absorb, as other areas desorb, to a total of almost 20 times man’s CO2 output. A slight imbalance might be sufficient to account for recent increases.
There is a good overvieuw of the CO2 absorption/release rates over a year with a lot of background information at:
http://www.pmel.noaa.gov/pubs/outstand/feel2331/exchange.shtml and following pages. Be it that the area/wind information is not completely correct. But the main direction is.
Even if the temperature e.g. at the poles, the sink places, dropped 1°C more than average, that doesn’t make much difference: the current CO2 level at about 400 ppmv gives about the same partial pressure of 400 microatm everywhere over the oceans (minus a few % due to water vapour). The pCO2 of seawater at near freezing is about 150 microatm. That gives a certain absorption rate, depending mainly of mixing speed by wind. With 1°C less temperature, the 150 microatm drops to 134 microatm, increasing the absorption of CO2 with some 6%. That reduces the CO2 content of the atmosphere, but as the CO2 pressure drops, more is released at the equator and less is absorbed near the poles. At last somewhere halfway the extra pressure drop at the sink places (a drop of about 8 ppmv in the atmosphere), a new dynamic equilibrium is reached…
Thus local temperatures matter locally, but the global, area weighted average temperature is what matters.
I also find the claims that ice cores trap an exact representation of the air at the time the core is dated, extremely dubious. Beck and Jaworowski have been dismissed too easily.
Both are dismissed on firm grounds: many of the historic measurements were taken at completely unsuitable places and the late Jaworowsky’s knowledge ended in 1992 and was completely refuted by the work of Etheridge e.a. from 1996 on three Law Dome ice cores… See:
http://www.ferdinand-engelbeen.be/klimaat/beck_data.html
and
http://www.ferdinand-engelbeen.be/klimaat/jaworowski.html
If tou use the dust record, EPICA C, as Log)dust). You get a better correlation with temperatue over the last400 ky. In addition, dust changes before temperature.
There is a nice figure showing changes in Argon, as well as CO2 and Temperature. The Ar/N2 tracks temperature much bettwer than CO2.
Willis – I admired the hell out of you. The CO2 sensitivity argument is beautiful, forehead-slapping stuff. Doh! ;-D
But temperature rise by itself isn’t sufficient to explain the rise in CO2. Besides human input of CO2 (easy to default to this, confirmation bias, can’t think of anything else so this is the answer) – what other factors could explain? Changing CCD depth? What if the ‘ocean’ isn’t a single, well-mixed tank?
I am not understanding where you get the 23c sensitivity here. In the previous interglcial, temperature went from -4.5 to 1.4 as CO2 went from 195 to 270. Doesn’t that imply 8 to 10 C for a doubling?
Engelbeen: “An interesting part of the Vostok record is the end of the previous interglacial, the Eemian: while CO2 and temperature go up in parallel, temperatures go down while CO2 levels remain high. At the moment that the temperature is again at a new minimum (and ice sheet growth at a maximum). CO2 starts to go down. The 40 ppmv drop in CO2 level has no observable effect on the temperature record… See:
http://www.ferdinand-engelbeen.be/klimaat/eemian.html“
This is an extremely key point and is ignored by Mosher and others who are still trying to tie CO2 to temperature. While the “cartwheel paper” paper Mosher references (my name for it because it seems like they are turning cartwheels to find some plausible reasoning that CO2 lead temps) shows one possible explanation, it ignores the back end of the cycle where temperatures lead CO2 at a much longer timescale.
S. Meyer says:
January 3, 2013 at 11:35 pm
Professor Hayden at the ICCC7 reported a very striking 99% correlation between sea surface temperature anomalies and atmospheric log(CO2 ratio).
For a short period, yes, but that disappears if you extend the period back in time. Compare the emissions and temperature graphs with the increase in the atmosphere over a longer time span:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_emiss_increase.jpg
The correlations over the full period 1900-2004 are here:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/acc_co2_1900_2004.jpg
and
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_co2_1900_2004.jpg
The latter still shows some correlation, but a huge change in temperature of halve the scale has a small influence on CO2 levels, while the total change in temperature over 104 years should have a huge influence. As the ice cores with a medium resolution (21 years for the Law Dome DSS core) still show a small influence of about 8 ppmv/°C between the MWP and LIA, the strong influence of temperature on CO2 levels is entirely spurious…
Certainly. This is called feedback. Postitve feedbacks amplify, negative feedbacks damp the cause.
LearDog:
At January 4, 2013 at 4:57 am you ask
I answer: anything which alters the equilibrium state of the carbon cycle.
One such possible alteration is provided in my above post at January 4, 2013 at 3:21 am.
Please note that I provided that post because I suspected that Willis’ post script to his article could deflect from discussion of the forcing/feedback analysis in his excellent article and – instead – induce discussion of the cause of recent rise in atmospheric CO2 concentration. My purpose in providing that post was to explain that the cause of the recent rise cannot be resolved with now available data so discussion of it would be a pointless distraction from the analysis in Willis’ article.
Richard
richardscourtney says:
January 4, 2013 at 3:21 am
And if Middleton’s minimum closure time estimate of 30 years is correct then fluctuations similar to the rise in the Mauna Loa data would be more than halved in the ice core data.
The smearing within the ice cores mainly is near closing depth, where the density of the firn increased so much that exchanges with the open air are firmly restricted. Above closing depth there still is a lot of exchange with the above air by diffusion over the period to closure (40 years in the case of Law Dome). That makes that the average age of the air mixture at closing depth of the high resolution Law Dome ice cores is only 7 years older than in the above atmosphere. As the closing proces also takes a few years, the resolution of the bulk of the air in the bubbles is about 10 years, with some recent air and some older air, a long tail of up to 40 years. See:
http://courses.washington.edu/proxies/GHG.pdf
Fig. 11 gives the theoretical gas age distribution of the Law Dome ice cores, where the averages are confirmed by in situ measurements.
There is a 20 years overlap between the Law Dome ice core data and atmospheric data at the South Pole:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_sp_co2.jpg
That makes that the resolution of the CO2 levels (including the changes in 13C/12C and 14C/12C ratio’s) is by far enough to show any one-sided peak of 20 ppmv during one year or a sustained change of 2 ppmv over 10 years at the accuracy of the measurements in the Law Dome ice cores. Even a one-sided event as the current 100+ ppmv increase over the past 160 years (80 ppmv over the past 50 years) would show up in the Vostok and Dome C data…
Willis,
I call your attention to slides 51 through 56 of http://www.kidswincom.net/climate.pdf which is a similar analysis of the ice core data.
If CO2 lags ocean temps by 800 years, then we have a giant low pass filter and one will find little correlation between short term temperature changes and CO2 levels. The current rise in CO2 has more to do with the increase in temperature since the LIA.
Perhaps the thing about the Vostok graph which most non-specialists would be interested in hearing about is why the exit from ice ages is very rapid, but the descent into them is rather slow.
This does rather suggest that a unique input factor provides the stimulus to trigger exit, whereas the ice age stable state is merely reverted to through passive evolution of the earth back to base camp.
The key question is what that trigger/those triggers are??
Willis writes “They would not melt instantaneously, so deglaciation would necessarily lag temperature rise by some years. Since the deglaciation and CO2 rise are contemporaneous, we can conclude that the NH temperature rise must have preceded the CO2 rise, and not the other way around as they claim.”
I always find its the other end of the cycle to be most convincing (and least discussed by AGWers) When it begins to cool, CO2 continues to go up and maintains that lag. This can only mean that something else is driving the cooling and its so powerful that the current and increasing level of CO2 is overcome by it.
So “something else” forces the warming at the beginning and “something else” forces the cooling at the end and right the way through to at least when the CO2 levels have dropped again but more likely through to the beginning of the next interglacial and we’re supposed to believe that the “something else” takes a back seat in the middle of the warming bit to leave CO2 to drive the continued warming? Its a joke and a bad case of wishful thinking to support a theory.
History clearly shows us that CO2 comes along for the ride and that the other non-CO2 “natural” forcings are stronger than CO2.
I’m surprised more discussion of land use changes hasn’t occurred. We’ve seriously reduced the ability of the biosphere to absorb the CO2 added to the atmosphere. IIRC, the satellite survey of CO2 levels showed highest levels in 3rd world countries that have experienced a lot of deforestation.
“climate sensitivity would have to be 23°C per doubling of CO2”
When you get an answer that absurd, it might be prudent to ask first if the calculation was done correctly. Over the last termination, from your graph temperature increased by ~4C while CO2 increased by about 50% from 180 to 270ppm. This implies that a doubling of CO2 from 180 to 360 ppm would cause an 8C temperature increase, not a 23C increase.
This is still large relative to the 3C IPCC estimate, but that estimate excludes some slow feedback mechanisms like vegetation change and icesheet decay. Including these gives a higher earth system sensitivity of perhaps 3-6C. Still smaller than the 8C calculated above, but the 8C is not due to CO2 forcing and feedbacks, but to insolation forcing and feedbacks, so it is unreasonable to attribute it all to CO2.
Your Granger causality analysis is erroneous as it assumes that Vostock temperatures are in phase with global temperatures. At the first approximation they are – interglacials are approximately simultaneous in both hemispheres. But you just need to compare the details of Greenland and Antarctic records over the last termination to show that global temperatures cannot be adequately represented by a single location. Warming in Greenland started later than in Antarctica, so even if temperature leads CO2 in Antarctica (and that is in doubt with newer age models) it does not demonstrate that temperature leads CO2 on a global basis.
On the final episode of Star Trek the Next Generation, Picard and the Enterprise battle an anomaly that grows backwards in time, eventually effecting the future of humanity by preventing life on earth from ever starting. So if Hollywood teaches us anything, the future can change the past.
Otherwise, rising CO2 levels can’t cause the temperatures to increase first.
In the ace ages, CO2 changes from 185 ppm (glacial maximum) to 270 ppm (average interglacial at +1.0C) – while temperatures change by about 6.0C in an average glacial-interglacial transition.
5.35 Ln(185/270) = 2.2 W/m2 (add another 0.5 or so for CH4 and N20 GHGs for 2.7 W/m2 total).
But what was the Ice Albedo forcing? This is the pea under the thimble used by the pro-AGW climate scientists. If you deliberately under-state this forcing, then you can increase the CO2 climate sensitivity.
No Albedo change and the CO2 sensitivity is 6.0C for 2.7 W/m2 or 2.2C/W/m2.
But all those glaciers, sea ice and desert/grasslands and a -6 W/m2 increase in low cloud cover (IPCC feedback estimates) do not result in Zero Albedo change. It has to be a very large number.
I’ve only found TWO numerical estimates of the Ice Albedo forcing in the ice ages. -12 W/m2(surface only and this paper did not pass peer review) and Hansen’s deliberately low -3.5 W/m2.
You cannot estimate CO2 sensitivity in the ice ages or in the paleoclimate without having good Albedo estimates. In fact, you need this for every 500 year tranche of time going back 4.4 billion years in order to answer the question. Maybe there is also a CO2 to Albedo feedback and maybe there is a Albedo to CO2 feedback. We have the CO2 estimates but climate science refuses to put the Albedo numbers on paper in a transparent way. My estimate for the ice ages Albedo is -17 W/m2 based on my Albedo model.
Ice Age forcing = -17 W/m2 Albedo + -2.7 W/m2 GHGs = -19.7W/m2/6.0C = 0.3C/W/m2
Implying 0.3C/W/m2 * 4.2 W/m2 (CO2/GHG doubling) = 1.3C CO2 sensitivity
Richard Telford, wise up. There is no empirical evidence supporting the IPCC’s wild-eyed estimate. They simply picked a scary number and ran with it.
You assert:
“Your Granger causality analysis is erroneous as it assumes that Vostock temperatures are in phase with global temperatures.”
That is wrong. Both Greenland ice cores and Antarctic ice cores show high correlation. In other words, they are in phase.
Face the fact, Telford, that ∆CO2 is caused by ∆T, not vice versa. The alarmists’ premise is backward, therefore their conclusion is wrong. It is that simple.
@S. Meyer:
If there are other sources of CO₂ which increase its partial pressure at the ocean’s surface the ocean would not be able to outgas more. So the correlation woud be the same as if the ocean outgassed this CO₂. That means also that the ocean is a strong regulator in that regard.
FerdiEgb:
I am responding to your post at January 4, 2013 at 5:43 am so you can see I have not ignored it.
However, I am not replying except to say that your logic is very flawed so your conclusion is fallacious. The reality is as I said in my post at January 4, 2013 at 3:21 am.
That is my final comment on the matter because, as I said (at January 4, 2013 at 5:15 am) of my post at January 4, 2013 at 3:21 am
Whether you or I am right about the ice core data does not affect Willis’ analysis in any way: it is only relevant to the cause of recent rise in atmospheric CO2 concentration.
Richard
The title of the article “Does The Effect From The Cause Affect The Cause?” nicely illustrates the nonsensical contortions that are needed to squeeze an AGW story out of a record of CO2 lagging temperatures. (It is also a good example of the two different spellings of “effect/affect” used in the correct way unlike many WUWT posters.)
A lot of trolls have swooped in as usual for a CO2 related thread. The issue of feedbacks is raised but trying to understand feedbacks in climate without a framework of a nonlinear/nonequilibrium dynamic system is like trying to understand chemistry without the periodic table. If we are to believe that temperature first increases for some unknown reason, then causes CO2 to increase, and that CO2, having been caused by the temperature increase, then changes from being the forced to the forcer on account of a strong positive feedback and usurps the leading role… then, a very strong positive feedback would be needed to even come close to causing this strange forcing reversal. Such a strong positive feedback would impose a simple monotonic oscillation on the system.
The heart-beat is an example is a nonlinear oscillation driven be strong positive feedbacks, the result is a regular simple oscillation. (Things which interfere with this simple oscillation making it irregular are the subject of cardiac pathology, there is a lot of published nonlinear maths on the subject.) Conversely negative feedback constitutes damping and introduces complexity to the nonlinear oscillation. Thus the signature of an oscillation dominated by strong positive feedback is clear, a monotonic oscillation, and this is not seen in the climate record. (What is actually seen suggests competition between a number of positive and negative feedbacks).
This proposed CO2-temperature two-step is rather like a biologist proposing that the head and the tail of a dog could exchange places on the animal during the dog’s lifetime.
D Böehm says:
January 4, 2013 at 6:42 am
Richard Telford, wise up. There is no empirical evidence supporting the IPCC’s wild-eyed estimate. They simply picked a scary number and ran with it.
You assert:
“Your Granger causality analysis is erroneous as it assumes that Vostock temperatures are in phase with global temperatures.”
That is wrong. Both Greenland ice cores and Antarctic ice cores show high correlation. In other words, they are in phase.
————————–
You might not like the empirical evidence of climate sensitivity, but it is foolish to say there is none.
Sure d18Oatm is in phase between Greenland and Antarctica. That is not in the least surprising as the 18O has a long life span in the atmosphere and is well mixed. But the Vostock dD record is not in phase with the GISP2 d18O record. Sure they are not in antiphase, I never argued that they were, but as the figure you link to makes clear, Antarctica temperature leads Greenland temperature at the last termination.
Just because the correlation is high, does not mean the records are perfectly in phase.
Thanks, Willis. Excellent post.
This article now has 4 more links for my climatology pages.
@crosspatch
See: http://www.appinsys.com/GLobalWarming/SixtyYearCycle_files/image002.jpg
That shows we had very similar variation in tides then, too. Tides change depth of surface mixing, so cooling from the water. I’m now wondering if that can also change CO2 levels…
The warm and cold cycles of history match rather well with tide forces based on lunar cycles of motion.
http://www.pnas.org/content/97/8/3814/F1.large.jpg
More detail here:
http://chiefio.wordpress.com/2013/01/04/lunar-cycles-more-than-one/
There is also a variation in the Gulf Stream and where it cools / descends that causes it to sporadically ‘back up’ and cause cold ‘far north / EU’ and a warmer Florida. This would mean that differential heat levels would be made even higher. For Florida, that means more rain washing the carbonation into the soil to erode the Karst soils. I wonder if there are any ‘rate of erosion’ data that could show CO2 / acidity changes… Having a much colder polar water with faster rain washing in the tropics sounds to me like a formula for CO2 stripping…
In general, I notice that everyone talks about CO2 dissolving into the ocean surface, but that ignores the rain falling through the air (rather like a counter current stripper). I think gig-tons of snow and cold water falling through the air will tend to remove a lot of CO2 into water puddles, rivers, and into the ocean.
Also, we’re at the top of a warming cycle and the deep ocean is still near max cold. There just isn’t going to be a lot of thermal degassing of the deep layers until they become surface layers. We’re limited by ocean overturn speeds.
That means changes in THCirculation speed of the ocean can change rate of CO2 both in and out.
Rain also is likely why glacials end faster than they form. A warm rain melts snow and glaciers fast. But a cold snow can only deliver its own mass of snow… Mass flow limited ice growth and in times of decreasing precipitation. For glacial loss, increasing precipitation and warmer melting ice.
Maybe we need a mantra… “Don’t forget the precipitation”…
Mosher – I can visualize Mosher standing in the center of his eclectic San Fransisco flat doing a pirouette with his damp finger in the air.
Chiefio
You made the interesting comment above;
“In general, I notice that everyone talks about CO2 dissolving into the ocean surface, but that ignores the rain falling through the air (rather like a counter current stripper). I think gig-tons of snow and cold water falling through the air will tend to remove a lot of CO2 into water puddles, rivers, and into the ocean.”
Surely clouds- or more correctly the water vapour they consist of-must also be full of co2? Has anyone ever specifically measured the co2 content of a cloud as opposed to ‘the general atmosphere’ at ground level such as at Mauna Loa
How many tons of co2 is that directly delivering into the oceans/land each year?
Does that mean that clouds are strongly negative because they remove co2 fromn the atmosphere? (irrrespective of their cooling effect by shielding the sun)
tonyb
Powerful argument. I am new to Granger causality. Is there a fifth outcome in which the Granger test would suggest that both temperature and CO2 respond to an entirely different driver? In comparing the two curves, that seems to be a legitimate third possibility beyond one driving the other.
Being the world biggest dummy,I should not be writing here. When I started to school it was in a two
room school bldg. grades 1-5. When in thr 3rd grade there was a hugh world map hanging at the front.Each day I would stare at it and wonder.One day I said to my self,Africa and S.A. were once
conected.One day I said to the teacher I think Africa and S.A. were at one time conected.Her reply was”you are the worlds biggest dummy.” I learned my lesson, I never asked another question the
whole time I was in school. Many years later waiting in a doctor’s office I picked a mag.and read
the contenants were once conected,I said I always knew that !
Now my question,when guys are looking 1000ky,what does the earth look like in your mind.Is it
like it looks now? Was the ocean larger than now? Was there more “dirt”then? Would any of this
make a difference?
his name “was Pegleg;because in his days the earth was divided” I Chron.1:19
A
E.M.Smith says:
January 4, 2013 at 8:05 am
Having a much colder polar water with faster rain washing in the tropics sounds to me like a formula for CO2 stripping
When water evaporates from the sea surface, CO2 is released too. That increases the CO2 levels near the sea surface (but that is readlily dispersed by convection, as good as the water vapour).
CO2 solubility in fresh water is very limited compared to seawater and mainly occuring at the CO2 pressure where the drops are formed. When these fall down, the CO2 pressure increases with the air pressure, but at the other side, temperature increases, thus decreasing CO2 solubility. And a part of the raindrops may evaporate at the surface, thus again releasing CO2…
Thus in balance, at most there will be some more CO2 near the surface than higher in the atmosphere. Hardly relevant (and hardly measured)…
That means changes in THCirculation speed of the ocean can change rate of CO2 both in and out.
Not important: even if the speed of the THC doubles, that doubles the CO2 releases at the upwelling side and CO2 uptake at the downwelling side. Net result: faster turnover, zero change in CO2 levels of the atmosphere. Only temperature (and human emissions) is important in changing the atmospheric CO2 pressure/levels…
Steven Mosher says:
January 3, 2013 at 9:26 pm
since hansen predicted the lag of versus temperature in 1990, folks might want to watch this
========================
“Crock of the Week” is an appropriate name for Peter Sinclair’s propaganda efforts. The target audience are persons of average intellect and scientifically illiterate. He offers comfort to the faithful at a time of evolving crisis, far different than that for which they had hoped.
richard telford says:
January 4, 2013 at 6:02 am
You are correct, I used the regular log rather than log to the base 2. However, the answer is still absurd, at 7°/doubling.
Thanks,
w.
Interestingly enough the same lag between temperature and CO2 is readily apparent in modern satellite data. http://www.woodfortrees.org/plot/esrl-co2/isolate:60/mean:12/scale:0.2/plot/hadcrut3vgl/isolate:60/mean:12/from:1958
Richard Telford still argues that there is not correlation between the hemispheres. How many examples does it take to correct his confusion?
Of course, if Telford admits there is a high correlation between the hemispheres, he loses the argument he has been trying to make. Telford’s “perfectly in phase” comment is just a failed attempt to get some wiggle room. The fact is that the hemispheres’ temperatures are in phase, as the three links I posted convincingly demonstrate.
W,
Regarding the sensitivity of CO2 to temperature, you’re comparing apples and oranges. There’s no reason that the sensitivity on time scales of tens of thousands of years (Vostok record) should be the same as the sensitivity on time scales of decades (modern record).
I have not yet seen the source of CO2 proposed if the CO2 really did rise before the ocean temp. Volcanoes? “Dry ice”, i.e. solid CO2, meteors? Massive methane releases from methane hydrate w/ the ocean at it’s lowest temp? Magic? C’mon!!!
The only explanation, based on the evidence, is the oceans started warming for some reason not related to a greenhouse effect then the oceans degassed CO2 at ~9 – 16 ppmv/°C w/ the CO2 conc. lagging temp by 800±200 yrs….but in spite of the lack of any evidence it still could be due to CO2 driving the temperature. (that last part required to keep faculty cocktail invitations and grant monies flowing in)
The steady state level of atmospheric CO2, in geological time, is dependent on the input rate and the efflux rate.
The input rate is the rate at which CO2 is released by vulcanos and mantle vents.
The efflux rate, or true sink rate, is the rate of mineralization or inorganic and organic, biotic, carbon; mostly due aquatic organisms.
If dust levels increase, then sun light is blocked, Earth cools, ice age starts. Dust is full of trace transition metals and fertilizes the oceanic deserts.
Total biotic productivity increases, deposition rate of organic matter to sea floor increases and [CO2] goes down.
Could you provide a CO2 vs Temperature graph, colour-coding the data by time?
The colour-coding will reveal non-CO2 causitive factors at play by showing a circularity in the temp-CO2 data points around some other central trend. If you don’t colour-code the time aspect, you get a spread of data that looks like normal variance or error bars.
I’d do it, but I am computer challenged and don’t have a 12-year-old with me.
See my article on the Central UK Max Temp vs Sunshine Hours for the idea.
Alfred Alexander says:
Who’s Pegleg? (I’ve heard of Peleg 🙂
M@WW says:
Regarding the sensitivity of CO2 to temperature, you’re comparing apples and oranges. There’s no reason that the sensitivity on time scales of tens of thousands of years (Vostok record) should be the same as the sensitivity on time scales of decades (modern record).
I don’t see the sensitivity should change if we’re talking about how much CO2 brine with contain. This is a function of T^5 not of time.
There will be different time constants for different magnitudes of change due to the different depth, hence volumes of water concerned.
You seem to be confusing the two.
M@WW says:
January 4, 2013 at 11:00 am
W,
Regarding the sensitivity of CO2 to temperature, you’re comparing apples and oranges. There’s no reason that the sensitivity on time scales of tens of thousands of years (Vostok record) should be the same as the sensitivity on time scales of decades (modern record).
There’s no particular reason to think it shouldn’t be the same, unless the goal is to hang onto a crumbling ideology. In addition, there is no evidence of a greater sensitivity in the modern record.
Hi Willis, Anthony and mods. You might enjoy this, though not strictly relevant to the thread!
On Positive Feedbacks in Climate
(Hat tip to Augustus de Morgan)
Great heats have lesser heats which grow before to cause ’em,
And little heats have lesser heats, and so ad nause-ausam.
The great heats themselves in turn cause greater heats in future,
And greater heats give “reasons” for politicals to loot yer.
(You can substitute “droughts,” “rains,” or “colds” for “heats” in the above).
Bill Illis is spot on:
‘You cannot estimate CO2 sensitivity in the ice ages or in the paleoclimate without having good Albedo estimates. In fact, you need this for every 500 year tranche of time going back 4.4 billion years in order to answer the question. Maybe there is also a CO2 to Albedo feedback and maybe there is a Albedo to CO2 feedback. We have the CO2 estimates but climate science refuses to put the Albedo numbers on paper in a transparent way. My estimate for the ice ages Albedo is -17 W/m2 based on my Albedo model.
Ice Age forcing = -17 W/m2 Albedo + -2.7 W/m2 GHGs = -19.7W/m2/6.0C = 0.3C/W/m2
Implying 0.3C/W/m2 * 4.2 W/m2 (CO2/GHG doubling) = 1.3C CO2 sensitivity
But this should not be such a big surprise to anyone – believe it or not, you can get the same result from IPCC Working Group documents – they just don’t make it into the Summary for Policy Makers! For example, IPCC have access to the HIGHTRANS suite of computer calculations that give the watts/square metre read out for each part of the log -curve of CO2ppmv….and that gives you roughly the 2 watts for CO2 for the 180-280 deglacial transition. The shortest cut is then to apply a factor (known as Lambda. L) to the equation T= L (watts per sq metre)…and at its outset IPCC argued for 0.8 as the likely factor. Thus, for 2.7 watts, the forced temperature would be 2.16 C. If you take the global shift as 6 degrees, that gives you a 36% amplification…and that is roughly what the ice-core literature of two or more decades assumes. However in IPCC4, Keith Shine argues that Lambda could be as low as 0.4, thus halving the previous estimate. I guess this lower factor might account for the low estimates of the IPCC model runs (who knows?).
Thus, for the CO2 effect, 2 watts per square metre would lead to 0.8 C and therefore about 13% amplification.
My own view is that the initiating mechanism is not small shifts in insolation hitting some kind of trigger related to snow albedo (the land-sea snow-ice area is relatively small compared to potential shifts in cloud amount and spatial distribution ) – rather it is shifts in global winds which likely relate to shifts in the jetstream (linked to…? UV radiation? Magnetic flux? Cloud Electrics?) – these shifts can be observed right now with the latest solar minimum….but the global picture is confusing….with cloud free areas of high pressure leading to record highs and other areas record lows, depending on the season.
The modern CO2 rise is about 100ppmv…and the curve is close to linear once the CO2 level rises above 50ppmv…so this latest 100ppmv should have delivered another 2 watts per square metre, as indeed IPCC calculate it has. Clearly we have not seen 6 degrees, nor is that expected. Their calculations show 0.8C to 0.4 C at equilibrium (assuming they acknowledge Shine’s work). And for the ‘doubling’ they calculate using HIGHTRANS…3.7 watts per square metre….which without alarming feedbacks, wouldl deliver at maximum, 2.96 C, or if Shine is right…then 1.48 (and no alarm!).
The modern record of 0.8 C would have to have no natural (cyclic) component at all if it reflected the effects of CO2, and we know this is not right because there was no expected CO2 effect before 1950, when half the warming had already occurred. So – IPCC are still just about in the ballpark with Shine’s Lambda of 0.4 but only IF all the warming since 1950 is a consequence of the CO2, or there is more warming in the (ocean) pipeline. I doubt this is correct and hence the Lambda is lower still – perhaps lower than Bill’s 0.3 (which would deliver 1.11 C for the doubling in 2050…..and that is where the EVIDENCE is pointing, and evidence that is IN the working group reports, but does not get through the filters to the SUMMARY FOR POLICY MAKERS.
Re: the video posted by Stephen Mosher.
At 9:27 the video references a paper, which says.
‘The radiative forcing due to CO2 may serve as an amplifier of initial orbital forcings’
The narrator then says, ‘Could the authors have made it any clearer.’
Well, yes they could. They could have left out that pesky ‘may’.
‘May’ in a scientific paper means, ‘we think this could be the mechanism, but don’t have evidence.’
This video is doing exactly what it purports to debunk by (so called) deniers. It distorts the science.
For me, the biggest giveaway has always been the turning points. The points where CO2 is following temperature up or down, then suddenly, temperature changes direction with no regard to the fact that CO2 is continuing in the same direction. If climate sensitivity were large such reversals in temperature, in direct contradiction to the direction of CO2, would be impossible. And yet they are what almost always happens.
Fred McCleney says:
”From the Greenland cores there are two really important considerations; (1) ~130k DOES NOT get us back to the start of the last interglacial, from which one can infer that the Greenland sheet may have completely melted away during the inception and early millenia of the Eemian!”
130 K DOES get us back to the very beginning of the Eemian, and in any case if the Greenland Icecap melted during the earliest Eemian, how did it manage to re-grow and cover most of Greenland to a depth of a couple of kilometres in just a few of thousand years with temperatures warmer than at present? Remember that the Eemian ice from GISP/GRIP/NGRIP/NEEM was deposited at approximately the same altitude and temperature as top of the current icecap.
Furthermore the latest (NEEM) ice-core did recover some MIS 6 ice (and probably the GISP2 core did as well). Also the youngest organic materials ever found under the Greenland icecap are 450 – 800 000 years old and beryllium exposure ages of subglacial rocks are similar.
Actually the reason it is so hard to get ice older than MIS 5e from Greenland is pretty simple. To get very old ice you have to drill down at an ice-divide, i. e. a place where the ice lies still because it flows away equally in two or more directions. Anywhere else the really old ice is long gone, having flowed down to the sea and melted. However it is clear that the Greenland ice did partly melt during the Eemian, which almost certainly means that the ice divide shifted considerably, and most of the older is therefore gone. Things are much easier in Antarctica where the ice is extremely stable, very thick, very sluggish and acccumulates very slowly. Even so it is only near the center of East Antarctica that very old ice is found.
Willis
There is still a “twenty” at the end of one paragraph where it (now) should be ‘only’ seven degrees.
[Thanks, fixed. -w.]
Matt Skaggs says:
January 4, 2013 at 8:26 am
Powerful argument. I am new to Granger causality. Is there a fifth outcome in which the Granger test would suggest that both temperature and CO2 respond to an entirely different driver? In comparing the two curves, that seems to be a legitimate third possibility beyond one driving the other.
You are correct.
Granger causation isn’t a form or type of causation. It is a test for the existence of causation by testing for correlation. Granger causation can result from a third common cause of a correlation between A and B (temperature and CO2).
Great article Willis. However, I think your last comment concluding that the rise in atmospheric CO2 not explained by increased ocean temperatures, must therefore be anthropogenic, is unjustified, as it doesn’t consider the effect of increased temperature on the land based sources and sinks. Even the IPCC report, AR4, indicate that land based sources and sinks of atmospheric CO2 are greater than the all the oceans combined and are therefore worthy of consideration.
Forested areas alone both absorb and release great quantities of CO2. Trees grow until eventually dying, then decomposing and returning the absorbed CO2 to the atmosphere. Given sufficient time, the absorption due to growth must eventually balance the release by decomposition, else the amount of dead wood will continually build up on the forest floor producing a mountain of wood on a geologic time scale.
The source and sink processes are not likely to respond identically to changes in climate, thus climate changes will upset this balance and cause forested areas to become net sources or sinks until an equilibrium is established again. The growth rate change in response to a climate change is immediate, while any change in the quantity of dead material rotting on the forest floor needed to reestablish a balance, depending on the tree species, could take tens or even hundreds of years to achieve. I suspect the decomposition/oxidation process may be more sensitive to temperature than the growth process, thus causing a forested area to become, for a limited time, a net source of CO2 with an increase in average annual temperature.
I have never seen this addressed when discussing recent atmospheric CO2 increases, but then, I am not a climate scientist that would be familiar with papers on such things, particularly since most are paywalled
I also find it useful, at times, to express atmospheric CO2 in terms that give a better perspective to most people – such as 27 tons per acre (at sea level) rather than 390 ppm by volume. Or, for carbon alone, 18 tons per acre. Most people have some feel for the area of an acre and how heavy a ton is and consequently, can put such relationships in perspective when told trees easily absorb atmospheric carbon at an annual rate of a ton an acre or more.
dan houck says:
January 3, 2013 at 8:15 pm
….I am new to this, and I was wondering why the recent (100 year) increase in CO2 ppm has been so linear. Can you point me to any references? Thanks.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>
You can try :
EASIER:
#1. http://www.greenworldtrust.org.uk/Science/Scientific/CO2-flux.htm
#2. http://www.greenworldtrust.org.uk/Science/Scientific/CO2-ice-HS.htm
Scientific
http://www.co2web.info/stoten92.pdf
http://www.rocketscientistsjournal.com/2006/10/co2_acquittal.html
http://www.rocketscientistsjournal.com/2007/06/on_why_co2_is_known_not_to_hav.html#more
Willis –
I track the monthly NOAA CO2 data, monthly Hadcrut3 temperature, Global Emissions (estimated from the BP statistical review), and monthly MEI, among other things.
There is a very clear relationship between the 12 month change in atmospheric carbon (GigatTonnes C ~=2.3*ppmv) , 12 month change in temperature, and carbon emissions, especially apparent on the 12 month averages of these things. Termperature leads carbon by 7 months, on an OLS best fit basis, when incremental carbon is linear fitted to incremental temperature and carbon emissions. Most interestingly, not only is the fit extremely close, but the residual has a striking relationship to the MEI index. I calculate Delta GT carbon = 6.5*Delta T+ 0.48*emitted carbon, which I make to convert to 2.8 ppmv per degree C. That’s much less than your figure, but given the timescales one would expect much more outgassing over a longer period because a greater quantity of water will warm.
Let me know if you want to see the fits, I can’t work this interweb-thingy to post it somewhere.
Hope this makes sense and is of interest.
crosspatch says:
January 3, 2013 at 9:58 pm
….All we need now is a cooling trend and it blows the entire thing right out of the water.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
With Hansen et al in charge of the records we can have snow in July in Alabama and he will still be declaring it is the 5th warmest year Ev’ah! /snark
Willis Eschenbach says:
January 4, 2013 at 9:20 am
However, the answer is still absurd, at 7°/doubling.
——————-
Ask an absurd question, get an absurd answer.
Make straw men, expect them to burn.
Firstly, no-one thinks that the glacial-interglacial difference in climate was entirely due to CO2 and CO2 driven feedbacks. Insolation changed, albedo changed, other greenhouse gasses increased – all these contribute to the glacial interglacial difference.
Second, you cannot directly compare the IPCC estimates of Charney sensitivity (which excludes slow feedbacks like ice sheets and vegetation) and earth system sensitivity (which includes slow feedbacks).
Steven Mosher, further to the video alleging that CO2 is necessary to explain the ice ages, let me recommend to you and other readers “In Defense of Milankovich“. Inter much interesting alia he says:
This size disparity between Milankovich NH summer forcing and CO2 forcing implies that IF CO2 is acting as a positive feedback, it will be very hard to find that signal in the data.
This reinforces the point that the presenter in your video was just blowing smoke when he claimed that CO2 was necessary to explain the ice ages, or that it acted as a feedback to those ice age changes. Maybe, but we have no evidence that it is so. As a result, for your video to claim it is established scientific fact is entirely incorrect.
w.
Lester Via says:
January 4, 2013 at 2:33 pm
Great article Willis. However, I think your last comment concluding that the rise in atmospheric CO2 not explained by increased ocean temperatures, must therefore be anthropogenic, is unjustified, as it doesn’t consider the effect of increased temperature on the land based sources and sinks.
Increased temperatures means more vegetation growth, both on land as in the seas and over glacial – interglacial transitions also less ice sheets and more land occupied by plants. Thus higher temperatures means more CO2 uptake out of the atmosphere by the biosphere…
That is confirmed by satellites (the “greening earth”) and by the oxygen balance: there is less oxygen use measured than should be from fossil fuel use. That means that the biosphere as a whole is a net producer of oxygen, thus a net user of CO2 by more growth than decay and a buildup of organic material in roots, humus, peat,.. until browncoal and coal. See:
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf
In short: the oceans can’t be the cause of the increase, by Henry’s Law and because the 13C/12C ratio is higher than in the atmosphere while we see a continuous drop in ratio both in the ocean surface layer and the atmosphere in ratio with human emissions.
The biosphere is not the cause, as is proven in the oxygen balance. All other sources are either too small or too slow.
Lester Via says:
January 4, 2013 at 2:33 pm
Curious. I get a different value.
About 730 Gtonnes C in the atmosphere
World surface is 1.26e+11 acres
That gives me 5.8, call it 6 tonnes of carbon per acre, not 18, which is equivalent to 22 tonnes of CO2, not 27 … what am I missing?
w.
PS—if CO2 is 27 tonnes per acre as you say, then carbon alone would not be 18 tonnes per acre as you suggest. Instead, it would be 27 * 12/44 = 7.4 tonnes per acre. Don’t feel alone, the dang math, it bites me all the time too …
Move North America 250 kms farther north. Is there a permanent ice age? Yup. Until the glaciers depress the northern-most Land enough to make it Ocean once again (which does happen). Then, the ice age is up for grabs as Milankovitch changes will govern whether there is an ice age or not.
But, move North America 500 kms farther north and the Earth is back into Snowball conditions again until North America is moved off of this location by continental drift.
No change in CO2 levelsl are required at all to explain these two scenarios. Only Land near or on the poles is required because ice-sheets build up on Land and not on the Ocean.
Peak Warming Man says:
January 4, 2013 at 12:26 am
So are you saying that you don’t believe that an increase in co2 in the atmosphere will increase the earths temperature?
>>>>>>>>>>>>>>>>>>>>>>>>>
The amount is minuscule. The IPCC Climate types had to combine the effect of CO2 AND H2O (calling it a feed back) to get the sensitivity they wanted. Unfortunately for them while CO2 has increased atmospheric water graph and temperature graph have not.
MIT Professor Richard Lindzen said in a WUWT guest post:
Given we are at the chaotic end time of a interglacial it is time to cut the bovine feces and actually do some science before we are blindsided by a drop in temperature that is much more likely and much much more devastating.
The idiots in Washington D.C. listened to the Committee on Economic Development , the financial traders and the grain traders and got rid of the US food reserves. (Think 2008 Food riots) The French Revolution tells us what happens when people get really hungry because of the idiocy of their political leaders. Despite Homeland Security Secretary Janet Napolitano pointing fingers at American red necks it is the inner city drug runners and street gangs that are going to be really dangerous and gun laws will have zero effect on them.
The ABA Band of Bakers has already marched on Washington, D.C due to the ‘record high wheat prices and tight supplies.’
“Increased temperatures means more vegetation growth, both on land as in the seas and over glacial – interglacial transitions also less ice sheets and more land occupied by plants”
This is not true.
The bioproductivity of the oceans is not temperature dependent, but nutrient dependent.
The bioproductivity of land mostly depends on rainfall patterns. Although you lose a lot of land under the ice, you get a lot back by the greening of the deserts and the drop in sea level.
This is what the land area was when the sea level was 110 meters lower than today:-
http://www.ngdc.noaa.gov/mgg/topo/pictures/GLOBALsealeveldrop110m.jpg
The great deserts we have today were not there during the last ice-age.
LearDog says:
January 4, 2013 at 4:57 am
…. Besides human input of CO2 (easy to default to this, confirmation bias, can’t think of anything else so this is the answer) – what other factors could explain? Changing CCD depth? What if the ‘ocean’ isn’t a single, well-mixed tank?
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
The other possibility is the effect of humans/animals on vegetation. There was the 1930’s Dust Bowl
“In 1935, one of FDR’s advisors, Hugh Hammond Bennett, was in Washington D.C. on his way to testify before Congress… A dust storm arrived in Washington all the way from the Great Plains. As a dusty gloom spread over the nation’s capital and blotted out the sun, Bennett explained, “This, gentlemen, is what I have been talking about.” link
That is perhaps the most dramatic effect but certainly not the only one.
36 million acres of natural forest are lost each year (Forests cover 31% of total land area )
Land degradation is a more subtle form of loss of plant life vigor.
DocMartyn says:
January 4, 2013 at 4:07 pm
The great deserts we have today were not there during the last ice-age.
——————————-
Sorry, but that just isn’t true. There is a large amount of data from pollen and palaeolake level to show that, at least the Sahara, was at least as dry in the LGM as it is now. Not only was the climate cool and dry, but the low CO2 concentrations cause physiological drought. See e.g. http://www.sciencedirect.com/science/article/pii/S0277379198000158 for a summary of the data.
Alfred Alexander says:
January 4, 2013 at 8:35 am
Now my question,when guys are looking 1000ky,what does the earth look like in your mind…
>>>>>>>>>>>>>>>>>>>>>>>>>>>
I think this site might answer your question
http://www.esd.ornl.gov/projects/qen/nercNORTHAMERICA.html
A paper of interest dealing with CO2 redience time and C12/C13 and C14 is over at CO2science.org
But, of course, the idea that high CO2 correlates with high temp is completely consistent with AGW.
Just saying.
“The radiative forcing due to CO2 may serve as an amplifier of initial orbital forcings”
Test this hypothesis by examining how CO2 lacks serving as an amplifier when temps are dropping after an interglacial.It would be impossible for temps to drop at all if CO2 were the amplifier.
How can the same levels of CO2 cause rising amplification,yet the exact same levels fail to amplify with temps dropping into ice age?
If CO2 were the main amplifier ,CO2 LEVELS WOULD NEED TO DROP PRIOR TO ANY TEMP DROP.
But we know that temp drop precedes CO2 level drop by 800 years.
CO2 cannot be the amplifier nor the driver.
I suspect that the orbital initiator is the amplifier as well as the driver.
trafamadore:
Please explain what – if any – relevance your comment at January 4, 2013 at 6:50 pm has to the subject of this thread.
Richard
Willis,
You appear to have confused the Charney sensitivity with the Earth System sensitivity. The Charney sensitivity is estimated to be about 3C per doubling. This is the rapid response to increase in carbon dioxide. It is the widely discussed number in the IPCC reports. The Earth System sensitivity includes slow albiedo effects (for example from ice sheet melting) and vegetation changes that are longer term than the Charney sensitivity. You have calculated the Earth System sensitivity. Your result of 7C agrees well with Hansen’s estimate of 6-8C here . It is good to see that you agree with Hansen on the calculated value of the Earth System sensitivity from the ice core data.
trafamadore says:
“But, of course, the idea that high CO2 correlates with high temp is completely consistent with AGW. Just saying.”
High CO2 also correlates with Ice Ages, and low CO2 correlates with high temperatures.
Just saying.
Willis, this post is priceless. A treasure trove of useful information. I cant wait for your next post.
Thank you, Dan Houck, for your question, which I am wondering about, too. The question was: why is the rise of CO2 in the atmosphere so linear? Linearity usually (but not always) indicates that we are dealing with a simple relationship between just two variables, such as y=ax+b…. Unless the linearity is an illusion and we are looking at a segment of a sinusoid or logarithmic curve or something similar. But, for the sake of the argument, let’s assume that the straight line is just that. BY the way, Professor Hayden’s 99 % correlation which I mentioned earlier is a similarly vexing straight line.
Gail, I followed you links, but I am as dumb as before. CO2 in the atmosphere is influenced by temperature, acidity of the oceans, ocean water turn-over, human emissions, plant growth, volcanic activity….. How, on earth, do all these activities add up to a simple straight line?
I have been thinking that maybe it is all ocean temperatures, but if Willis is correct, and the increase of CO2 per degree of temperature increase is only a few ppm, that idea does not hold water either.
If Professor Hayden were correct though, we would be looking at a doubling of CO2 for each 2 degrees of temperature increase. In that case, I’d come up with the following back of envelope estimation:
Lets suppose that the mixed layer of ocean currently contains 1000 GT of carbon, the atmosphere contains 836 GT, human contribution per year are about 10 GT.
Preindustrial carbon in the atmosphere was 450 GT or 209 ppm.
Not sure what preindustrial carbon in the ocean was, but let’s assume about 1000 GT.
Now, for no temperature change, one would have a preindustrial equilibrium of 450/1450 (atmospheric carbon over total carbon). If humans add 1000 GT to the system (over 100 years), a new equilibrium would develop:
450/1450 = x/2000; X= 621 GT of carbon in the atmosphere, corresponding to 289 ppm. Without any warming, even a huge emission of 1000 GT would not raise atmospheric carbon all that much.
Now, if we assume that two degrees of temperature increase moves the equilibrium from 450/1450 to say 900/1450 (in the absence of any human influence), we would expect 419 ppm in the atmosphere just from 2 degree warming.
Now, if we add human emissions to the 2 degree warmer world, we would get 900/1450 = x/2000; x = 1241 GT of carbon in the atmosphere, or 578 ppm in the atmosphere from a combination of 2 degree warming plus 1000 GT of human emission.
Note that the above is very flawed, as it assumes that all the human emissions are added all at once, and it does not take into account deep ocean sinks, vegetation sinks and, and, and.
If on the other hand, one uses an estimate of only 12 ppm per degree of temperature change, the whole thing does not work.
But then… Explain the straight line?
Oops, typo, put in the wrong number for human emission… Should have been 550 GT.
Willis, you are correct of course, 12/44 is the correct ratio to use which gives a little over 7 tons per acre of CO2. For some unexplained mental lapse (not double checking a quick series of computations) I had used 29/44 which is the ratio of average air molecular weight to the CO2 molecular weight rather the using 12, the atomic weight of carbon.
I obtained the 27 tons per acre by multiplying 390 ppm by 44/29 to get 592ppm of CO2 by weight and then, at sea level, the atmospheric pressure being 14.7 psi, which is the weight of the atmosphere above one square inch of which .0592% or 0.0087 psi is due to CO2. This corresponds to a CO2 partial pressure of 1.25 lbs per square foot or 54,574 lbs per acre (the 27 tons per acre) unless I made another dumb mistake.
Anyway, I hope I made the point I was trying to make about using units that can be useful when making mental comparisons to certain sinks and source data. Pointing out my error at least let me know that someone actually paid attention to what I said.
Willis, I believe the difference between your 22 tons/acre and my 27 is your method gives a value based on distributing the CO2 equally above the Earth’s surface. Since land masses rise above sea level, thus displacing some of the atmosphere, its distribution isn’t uniform . At higher elevations you have less atmosphere and, consequently, less CO2 above you. The local atmospheric pressure can tell you how much CO2 you are looking through when gazing at the sky (after correcting for humidity)
On Earth, sea level is a convenient reference point. Lack of a sea level makes it difficult when making similar comparisons on the planet Mars. I suppose one must use the average elevation. At the average elevation of Mars I once calculated that you are looking through 27 times the amount of CO2 that you do on the Earth at sea level. (but I could easily have made more dumb errors).
Gail Combs says:
January 4, 2013 at 5:54 pm
Gail, how many times one need to point to the obvious: the residence time of any CO2 molecule (whatever its source) has nothing to do with the decay time of an excess amount of CO2 (whatever its source) in the atmosphere. Thus Segalstad and Essenhigh and you and so many others are comparing two completely different, independent of each other half life times.
If you have made an investment in a factory, you may be interested in the turnover and the gain of that factory: the turnover is how fast your investment (in the form of raw materials) is going through the factory and recycled. But more interesting is the gain (or loss) of your investment: that is what is left over after all costs are substracted from the sales price. Two total different things. You can double the turnover speed, but still you can have a loss or a gain or a break-even at the end of the year…
Thus the ~5 years residence time of any CO2 molecule in the atmosphere says next to nothing about what happens at the end of the year (after a full seasonal cycle). What is measured is a net loss of ~4 GtC/year for the natural cycle. That gives a e-fold decay time of ~210/4 or ~52.5 years or a half life time of ~40 years.
The human contribution nowadays is ~9 GtC/year, one-way addition. Thus if that CO2 is not disappearing in space, it is the sole contributor to the increase.
dan houck says:
January 3, 2013 at 8:15 pm
I am new to this, and I was wondering why the recent (100 year) increase in CO2 ppm has been so linear. Can you point me to any references? Thanks.
The increase is not completely linear, but slightly exponential. It follows the human emissions, which are slightly exponential too, with an incredible fixed ratio over the period since the start of the industrial revolution. See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_emiss_increase.jpg
Temperature on the other hand has periods with negative correlation (1945-1975 and 2000-current) and positive correlation (1910-1945 and 1975-2000).
Willis Eschenbach says*:
January 4, 2013 at 12:54 am
“You’re busting me because my graph doesn’t look like your graph? It doesn’t show the details you say that you are interested in?
Well, since in this topic I could care less about the details, and I’m just interested in the overall view, I use an overview graph. So sue me.”
I was just pointing out something helpful, which would aid the article’s presentation. The overall theme of the article’s text is that CO2 variation is not the main driver of the temperature variation. That overall theme is not a mere detail, and posting zoomed-in data as well would aid that presentation, since the zoomed in version drastically highlights how the temperature curve is not the same as the CO2 curve. For instance, in the article, you state: “You can see in Figure 1 that the temperatures rise and then stabilize, while the CO2 keeps on rising. The same is shown in more detail in the Greenland ice core data, where it is clear that the temperature fell slightly while the CO2 continued to rise.” What would particularly fit the latter text would be visual display of http://www.climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif highlighting divergence in CO2 and temperature trends.
* regarding when I wrote on January 3, 2013 at 8:53 pm:
“Some good points.
But a graph so zoomed out as figure 1 should be posted with a more zoomed-in version too. For instance, the following, while somewhat like the GISP 2 plot I often post, is for Vostok data specifically to match the Vostok subject of this article:
http://c3headlines.typepad.com/.a/6a010536b58035970c01348128c941970c-pi
Without [solely] a graph so zoomed out as to make a millenium be close to a pixel, without century-scale info in the data being hidden, CO2 being the prime driver of temperature becomes blatantly absurd, as opposed to the oceans slowly warming or cooler (slower than the surface), with the temperature affecting CO2 release or absorption as this article notes.“
S. Meyer says:
January 4, 2013 at 7:18 pm
If Professor Hayden were correct though, we would be looking at a doubling of CO2 for each 2 degrees of temperature increase.
I have followed the lecture of Professor Hayden at the ICCC7 (I was at the ICCC8 in Munchen BTW) conference. What he doesn’t show is the correlation between human emissions and the CO2 increase and he doesn’t show the (lack of) correlation between temperature and CO2 levels outside the most recent period (negative during 1945-1975). Further, he shows the solubility curve of CO2 in water (seawater is different, but that doesn’t matter here), but doesn’t apply that to his CO2/temperature estimate…
Further, if we may assume that the oceans are the main driver, that would mean that the maximum release is 12.5 ppmv/°C (16 ppmv/°C according to other sources). Thus not more than 10 ppmv since the depth of the LIA. The rest of the 100+ ppmv (80 ppmv since the measurements at the South Pole started) is NOT from the seawater temperature increase.
Then from a process viewpoint:
– the CO2/temperature dependency over the seasons globally is about 5 ppmv/°C
– the year to multi-year temperature induced variability around the trend is 4-5 ppmv/°C
– the multi-decade to multi-millennia temperature dependency is ~8 ppmv/°C
But according to Professor Hayden, and many others here, the temperature dependency of CO2 on the scale of 5 decades is over 100 ppmv/°C.
Any bet what kind of natural process(es) should perform the above behaviour of modest – hughe – modest response? Including a match with other observations like the mass balance, the 13C/12C and 14C/12C trends, the oxygen balance, the increase of carbon species in the ocean surface and vegetation, etc…
FerdiEgb , Thanks for the link to the paper you referenced indicating the biosphere has recently been a net producer of 02 while CO2 levels are simultaneously increasing. This conclusion was based on precise measurements of the atmosphere’s O2/N2 ratio and indicates that the biosphere’s response to increasing temperatures is to increase plant growth rates faster than decomposition rates. I would not have expected this to be the case as the decomposition process involves oxidation reactions that are exponential functions of temperature while the alarmists have been been arguing for years that the plant growth process is limited by, and dependent on, factors other than just temperature.
One problem I have with their paper, is that the authors never seem to consider nitrogen fixing properties of the biosphere which convert atmospheric N2 to NH3. They seem to assume any change on the O2/N2 ratio is due solely to changes in O2. The lack of any accounting for natural nitrogen fixing processes is a loose end that doesn’t seem to be addressed, but then, my quick scan of the paper may have missed something somewhere. It may very well be too small to effect their conclusion but should be addressed in their paper.
The carbon flux from the biosphere is very large compared to the flux from anthropogenic sources and small errors in the determination of natural processes can be meaningful. Particularly when the conclusions are based on very small measurement differences to begin with, as is the case here.
dan houck:
I hesitate to enter your discussion because it is off-topic from the fine article by Willis. Indeed, I attempted to deter this inevitable side-track in my post at January 4, 2013 at 3:21 am and explained why I think the side-track needs to be avoided in my posts at January 4, 2013 at 5:15 am and at January 4, 2013 at 6:46 am.
I am providing this brief answer to your question in hope that the side-track can be halted.
At January 3, 2013 at 8:15 pm you ask
As Ferdinand Engelbeen says at January 5, 2013 at 12:11 am, it is not linear. The apparent linearity results from the short time (i.e. 55 years since 1958) over which the increase has been monitored.
Ferdinand and I strongly dispute what can be deduced about the cause of the rise (he is convinced the cause is anthropogenic while I don’t know if it is anthropogenic or natural). My view is outlined in my post at January 4, 2013 at 3:21 am and slightly clarified in my post at January 4, 2013 at 5:15 am.
You ask for references. I commend that you refer to Ferdinand’s excellent blog where I suspect you will find all you want and I know you will find his explanation of the cause of the rise.
Richard
Lester Via says:
January 5, 2013 at 5:51 am
They seem to assume any change on the O2/N2 ratio is due solely to changes in O2.
Indeed there is no account for N2 fixation. This indeed may influence the oxygen balance and explain a part of the unexplained variabilty between the different stations. But the main problem is the necessary accuracy of the method, including sampling and handling: less than 1 ppmv oxygen on 200,000 ppmv… A strong example of modern analytical possibilities…
richardscourtney says:
January 5, 2013 at 5:52 am
I commend that you refer to Ferdinand’s excellent blog where I suspect you will find all you want and I know you will find his explanation of the cause of the rise.
Wow! Thanks a lot, Richard, for your kind words…
Here is the URL for those who are interested:
http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html
FerdiEgb,
I have not yet found a treatment of the effect of carbonic anhydrase on the biological carbon-isotope ratios. This seems surprising to me since this ubiquitous enzyme accelerates the
CO2 + H2O=H2CO3 exchange reaction by about 7 (seven) powers of ten above it’s, rather slow, uncatalyzed rate. I would have thought this would be more significant than the much less frequent reactions occuring during photosynthesis, especially in oceanic environments.
Do you know of such treatments in the literature?
Ferdinand Engelbeen says:
January 5, 2013 at 12:01 am
Gail Combs says:
January 4, 2013 at 5:54 pm
Gail, how many times one need to point to the obvious: the residence time of any CO2 molecule (whatever its source) has nothing to do with the decay time of an excess amount of CO2 (whatever its source) in the atmosphere. Thus Segalstad and Essenhigh and you and so many others are comparing two completely different, independent of each other half life times….
The human contribution nowadays is ~9 GtC/year, one-way addition. Thus if that CO2 is not disappearing in space, it is the sole contributor to the increase.
>>>>>>>>>>>>>>>>>>>>>>>>>>>
The key points that you believe:
1. CO2 is a ‘well mixed’ gas in the atmosphere despite all the sources and sinks, despite the 180 ppm reading in the ice cores being too low to support C3 plants, despite the daily and seasonal sawtooth Also see former EPA scientist – slide 24: “Most of the atmospheric carbon dioxide is being transported by water droplets.”
2. That the historical data in Beck ‘s compendium and the Ice Core data published before 1985 pointed out by Jaworowski and Segalstad are all too high and should be tossed out.
3. There is no other explanation for the 2% change in the C13/C14 ratio except Mankind’s use of fossil fuel.
………
I do not agree with any of these ASSUMPTIONS as you well know. If there has been no actual increase in the CO2 as the historical data shows but that you and the climastologists ignore, then ” the decay time of an excess amount of CO2 (whatever its source) in the atmosphere” has no meaning because there IS NO ‘EXCESS’
For those wanting to see the other POV. Historic variations in CO2 measurements.
For the last assumption here is the data that blows it out of the water.
C13 percentage:
C3 plants = 28%
C4 Plants = 14%
Air = 8%
Slide 21 from Biology course
To change the atmospheric ratio of C12/C13 all you have to do is change the ratio of C3 to C4 plants. AS E. M Smith said Over the last 100 years we’ve planted one heck of a lot more grasses world wide than ever before. Grasses are often C4 metabolism… Corn and sugar cane are also C4 while trees are C3.
It is also worth looking at F. H. Haynie’s presentation since he is an Environmental Scientist retired from the EPA.
Does carbon cycle round and round in the Carbon Cycle? Yes thank goodness, and some of it has been recycled for millions of years. All humans are doing is seeing the carbon continues to cycle.
Warmth (not warming) causes the atmospheric CO2 rise. When the cooling really kicks in, the change in CO2 will decrease. The annual CO2 cycle (caused itself by the annual temperature cycle) causes the annual change – it’s like a CO2 ‘pump’. At higher temperature levels it pumps the CO2 out of the water and at lower temperatures vice versa.
michael hart says:
January 5, 2013 at 10:55 am
I have not yet found a treatment of the effect of carbonic anhydrase on the biological carbon-isotope ratios.
From a quick search, it seems that carbonic anhydrase doesn’t discriminate against carbon isotopes at all. See:
http://www.chem.tamu.edu/rgroup/marcetta/chem636/Presentations/Carbonic%20Anhydrase-Randara.pdf sheet 20.
That plays a role in land plants: C4 plants use CA, which facilitates the uptake of CO2, while that isn’t used in C3 plants. See:
http://www.woodrow.org/teachers/esi/1999/princeton/projects/c3_c4/Group3web.html
As far as I remember from past discussions, part of the discrimination is at the air-water border in the stomata, similar for C3 and C4 plants. That gives an overall discrimination of -4 per mil for C4 plants and -16 to -18 per mil for C3 plants against the d13C level in the atmosphere.
That plays no/less role in marine plants, as most of CO2 (over 90%) is already present as bicarbonate (less than 10% as carbonate) and CO2/H2CO3 is less than 1% of the equilibrium between CO2/H2CO3 HCO3- CO3–
Hope this helped…
I thought I saw on this site some time back a home experiment you can do to show that temperature causes an increase in atmospheric CO2 levels.
Gail Combs says:
January 5, 2013 at 11:25 am
Dear Gail, you have done a lot of research. Unfortunately not at the right places…
1. The difference between “background” and other CO2 levels:
CO2 is not well mixed in 5% of the atmosphere: that is in the first few hundred meters over land. In all the rest of the atmosphere the levels are within +/- 2% of the full scale, including the seasonal variability and the NH-SH lag. See the difference between the raw data for “baseline” stations from near the North Pole (Barrow), Mauna Loa and the South Pole and those of Linden/Giessen over a few days. Linden/Giessen is where one of the main series of the late Ernst Beck’s 1942 “peak” in CO2 was based on:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/giessen_background.jpg
Further, land plants as usual grow on land, where CO2 levels are average 40 ppmv higher than background and even higher during inversion, giving at least a few hours of sufficient CO2 during ice ages.
“Most of the atmospheric carbon dioxide is being transported by water droplets.”
Did you make any calculation? I didn’t, but if that were true, there should be large differences between CO2 levels on rainy and clear days and between altitudes: less CO2 where the drops are formed and more CO2 at sealevel… As far as I know, no such huge differences exist…
2. Ice core and historical data.
The late Ernst Beck’s historical data compilation suffers from site bias: including series like the Giessen data makes his compilation as good as worthless, as there is no connection with the “background” CO2 levels of that period. That is confirmed by all other observations: nothing unusual around 1942 in high resolution (less than a decade) ice cores, not in coralline sponges and not in stomata data.
The late Jaworowski objected to the deleting of outliers in the oldest ice cores, where drilling fluid was detected in some of the samples, leading to a large variability of CO2 levels. These were rightfully discarded, as the cause was known and repeating of the drilling didn’t show high values.
3. ” the decay time of an excess amount of CO2 (whatever its source) in the atmosphere” has no meaning because there IS NO ‘EXCESS’
If there was no excess, why should nature be a net sink for CO2, if there is no driving force at all to absorb more CO2 than it releases?
4. The C3 and C4 plants.
Please, if you copy something, look at what is really written: the 13C/12C ratio is expressed as per mil d13C, not percent, and is negative for many species (except carbonate deposits and the oceans):
C3 plants: -28 per mil
C4 plants: -14 per mil
air: -8 per mil and falling.
One can imagine that more plant decay, as good as fossil fuel burning (at -24 per mil for coal and oil to -40 per mil for natural gas) will lower the d13C level in the atmosphere. But the oxygen balance shows that the biosphere is a net source of O2, thus a net sink for CO2 and preferably of 12CO2. Thus leaving more 13CO2 in the atmosphere. Thus NOT the cause of the d13C decline in the atmosphere, no matter if C3 or C4 plants are involved. The only difference between these two is that the rate of change to the wrong side is different…
5. The work of Fred Haynie.
My impression is that Fred gives too much weight at curve fitting, without any plausible explanation of the cause-effect relationship. Take e.g. his slide 32: there is a nice relationship between d13C change and temperature change over the period 1950-present. But there is hardly any cause-effect relationship: even over the huge temperature changes between glacials and interglacials, including the current Holocene, with the corresponding ice sheet cover changes, the change in d13C was only a few tenths of a per mil. Meanwhile we see a drop of 1.6 per mil since about 1850, completely in ratio with the use of fossil fuels. So how can slide 32 rule out the use of fossil fuels as cause, while that gives a perfect fit of the decline? See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
And again, I haven’t seen any calculation of quantities of CO2 released and absorbed by raindrops and their effect on local/global CO2 levels…
Hello Mr. Eschenbach,
I did not understand this Argument:
Quote:
“If we assume that the CO2 is giving 3° per doubling of warming per the IPCC hypothesis, then the problem is that raises the rate of thermal outgassing up to 17 ppmv per degree of warming instead of 15 ppmv. This is in the wrong direction, given that the cited value in the literature is lower at 12.5 ppmv”
Why is it the “wrong direction”? both 15ppmv and 17ppmv are larger than 12.5ppmv.
I calculated using a simple converging series, that a feedback of 1.92° per doubling of CO2 would increase the effective rate of thermal outgassing from 12.5ppmv/° to your observed 15ppmv/° on a basis of 200ppmv.
MB
Thanks for the reply, Ferdinand.
I think the isotope mentioned in the first ref was deuterium only, not carbon, and, as the article points out, the breaking of H-bonds is thought not to be part of the rate-determining step(s). So I think my question remains unanswered.
(There is in fact more literature I have found with a cursory look, but if I was missing something really obvious I thought you might be a person aware of it before I spend more time.)
michael
Hi Willis,
The circumstance whereby X is said to be Granger-caused by Y is said to occur when the function X contains information found in historical part of function Y that is not contained in the historical part of function X.
An essential requirement is that some information originates in Y before it is found in X.
In the case where Y is purely an element of a feedback loop around X, the function Y derives all its information from X so it cannot Granger-cause X.
More generally, when X and Y are in a feedback loop where only one element is driven, whichever is that driven element will Granger-cause the feedback element but not vice versa.
In your case, unless Y could be shown to have some significant driver independent of X, you should not expect evidence for X being Granger-caused by Y.
Alex