About the reliability of ice cores…
Guest Post by Ferdinand Engelbeen
There have been hundreds of reactions to part 1 about the mass balance (http://wattsupwiththat.com/2010/08/05/why-the-co2-increase-is-man-made-part-1 ). Many respondents still are not convinced that the mass balance is a firm proof that the observed increase of CO2 in the atmosphere is human made. But there are more indications. Ultimately, any alternative explanation must fit all the observations. If the alternative hypothesis fails even only one of the observations, then the alternative is rejected. But before we start to look at more observations which support an anthropogenic cause, we need to address several misconceptions which fly around on the Internet, mainly on skeptic blogs… This part has a detailed look at the reliability of ice cores, which are quite important for our knowledge of the pre-industrial CO2 levels, but have been subject to a lot of critique.
Note that the ice cores only show CO2 levels back to about 800,000 years, but measurements may in the future be extended to over one million years. What is found in the ice cores is only relevant for the most recent period of our history and not for more distant geological time periods.
About the reliability of ice cores:
Some have objections to the ice core measurements, as these are regarded as the main reason for the “equilibrium” assumption of ancient CO2 levels. The only real problem in this case is the smoothing of CO2 levels. That depends on the snow accumulation rate, as it takes a lot of time to close all air bubbles in between the snow flakes. That happens at a certain depth where the pressure is high enough to transform the snow, then firn (densified snow still with open pores) into ice. The averaging happens partly because at first the firn pores are large enough to let the air in the pores and in the atmosphere exchange with each other, partly because some bubbles close early, others at a lower depth (thus contain air which is different in composition, “age”, than other already closed bubbles). The depth where this happens depends on the pressure from the layers above and the temperature of the ice. The time needed for full closure of all bubbles largely depends on the accumulation rate of snow at the place where the ice core is taken (or upstream if coring at a slope).
That makes that the average smoothing of CO2 levels is about 8 years (Law Dome 2 out of 3 ice cores, 1.2 m ice equivalent/year accumulation), some 21 years (the third Law Dome ice core, 0.6 m ice equivalent, see http://www.agu.org/pubs/crossref/1996/95JD03410.shtml unfortunately behind a pay wall…), some 570 years (Dome C, a few mm/year, see http://www.nature.com/nature/journal/v453/n7193/full/nature06949.html ) and everything in between. The Law Dome closing period of the bubbles was measured, while for Dome C one needed models to estimate the time resolution in the far past.
Thus the smaller the snowfall at a certain place, the longer it takes for the bubbles to fully close and the longer averaging one has. At the other side, the smaller the accumulation rate, the further we can look back in the past, as for the same depth of ice, there are many more years of snowfall.
The fact that the pores still are open over a long period, also means that there are differences in the age of the ice and the age of the enclosed gas. The age of the ice can be counted, as it simply is the result of ice formation from yearly snow accumulation where winter/summer snow density differences gives clearly distinguishable layers if there is sufficient accumulation. If, as depth increases, the pressure and/or flow result in layers that are near invisible, one may use several other methods like electro conduction or X-rays (see http://iopscience.iop.org/1742-6596/41/1/034/pdf/jpconf6_41_034.pdf ) to distinguish the layers/age.
Determining the gas age is not as easy. Over the years of accumulation of the snow/firn, the pressure builds up and the firn becomes more dense with decreasing pore diameter. That reduces the exchange of air in the pores with the air in the atmosphere, until the pores are too small to make any further exchange possible. If there has been considerable accumulation, as in the two fast Law Dome cores, at the depth of the first closing (about 72 meters) the ice is already 40 years old (40 layers), but the air has the average CO2 levels of less than 10 years ago, which makes the average gas age (including the average time for fully closing of all bubbles) about 30 years younger than the ice at the same depth. For the top layers, we have the advantage of direct measurements in the atmosphere for overlapping periods, which makes a comparison possible.
For cores with far less accumulation, the analysis is more problematic, as the difference increases with the reciprocal of the accumulation rate. During ice ages, there was less precipitation, thus increasing the ice age – gas age difference. The ice-gas age difference for the Vostok ice core is over 3,000 years. Be aware that the ice-gas age difference has nothing to do with the resolution of the CO2 levels, as these are in the bubbles themselves, but it makes a chronology of what happens between temperature (measured as dD and d18O proxy in the ice, see further) and CO2 levels (measured in the bubbles) more difficult to establish. But here also different techniques are used: diffusion speed is a matter of pore diameter, directly related to firn/ice density and densification speed is directly related to accumulation speed. This can be used to model the exchanges between air in the pores and the atmosphere.
The calculations to establish the gas age did fit quite well for the Law Dome ice cores, where besides ice age, the average gas age was established by measuring CO2 levels top down in the firn. That showed that the gas age at closing depth was less than 10 years old on average, but more importantly, the CO2 levels in the already fully closed bubbles and the still open pores were the same. For the low accumulation ice cores like Vostok, there is more discussion about the ice-gas age difference and different time scales were established…
The accuracy of the measurements in the three Law Dome ice cores for the same gas age is about 1.2 ppmv (1 sigma). Later works compared different ice cores for CO2 levels at the same average gas age. These show differences of only 5 ppmv, despite huge differences in average temperature (coastal -20°C, inland -40°C), salt inclusions (coastal), accumulation rate and resolution. There are a lot of overlapping periods between the ice cores, the resolution decreases with increasing length of period (from 150 years – for 2 of 3 Law Dome ice cores – to 800,000 years – Dome C), but even so, the measurements (done by different labs of different organizations) show a remarkable correspondence for the same average gas age. This is a nice indication that the CO2 levels of the ice cores indeed represent the ancient levels.
Data over the past 10,000 years of average gas age in ice cores from:
http://www.ncdc.noaa.gov/paleo/icecore/current.html
As result, for the past 150 years (Law Dome) we have accurate data with a reasonable resolution. The cores average the CO2 levels over 8 years, so any peak of 20 ppmv during one year or 2 ppmv difference sustained over 10 years would be observable. For older periods, the resolution is less and the averaging applies to the full period of resolution (about 570 years for Dome C).
The visual correlation between temperature and CO2 levels in ice cores is well known to everybody, as that was used by Al Gore and many others, although he forgot to tell his audience that the CO2 levels lagged by some 800 years during a deglaciation and many thousands of years at the onset of new glaciations:
Data from the Vostok ice core via:
The temperature is derived from dD and d18O proxies in the ice. dD means the change in the deuterium/hydrogen ratio measured in the water molecules of the ice and d18O is the change in 18O/16O ratio of the water molecules in the ice. Both heavier isotopes of hydrogen resp. oxygen increase in ratio to the lighter ones, when the ocean temperature, from where the precipitation originates, increases. Thus the change in ratio is an indication of the ocean temperature changes. For coastal ice cores, that indicates the temperature changes in the nearby Southern Ocean, while the deep inland cores receive their precipitation from the more widespread SH oceans, thus representing the temperature changes of about the whole SH. The NH ocean temperature changes are more or less represented in the Greenland ice cores, which show similar changes (over the last about 120,000 years), but with some differences in timing and more detailed extreme events (like the Younger Dryas).
There is a remarkable near-linear ratio between ice core CO2 and the temperature proxy record in the same core over 420,000 years of Vostok. Work is under way to confirm this ratio in the 800,000 years of Dome C (for the overlapping period, the CO2 levels are already confirmed similar): about 8 ppmv/°C:
Data of the Vostok ice core from NOAA, temperature proxy indication shows zero at current temperature. From:
http://www.ncdc.noaa.gov/paleo/icecore/current.html
The spread in temperature/ CO2 data, mainly at the high side, is from the long lag of CO2 levels which remain high for thousands of years at the end of a warm period, while the temperature is dropping back to a minimum. The 8 ppmv/°C is not absolutely right, because temperature at best represents a hemispheric ocean temperature, but not far off, as the pCO2 in seawater dependency of temperature shows about 16 ppmv/°C. But besides pCO2 of seawater, other land and (deep) ocean items also play a role.
This all is an indication that temperature is not the cause of the sharp increase of CO2 in the last 150 years, as that wouldn’t give more than 8 ppmv (or 16 ppmv based on ocean solubility) increase with a maximum 1°C temperature increase since the depth of the LIA, while the current increase is over 100 ppmv.
Be aware that, besides some fractionation of the smallest atoms/molecules (not of CO2), and a small fractionation of isotopes, the bubbles still reflect the ancient atmosphere as it was. Ice core CO2 thus is not a proxy but a direct measurement, be it smoothed, of what actually happened in the (far) past.
The objections of Jaworowski:
What about the objections of Jaworowski against the reliability of ice cores (http://www.warwickhughes.com/icecore/ )?
Jaworowski assumes that CO2 “leaks” via cracks in the ice, caused by the drilling and pressure release of the deep core ice. But how can they measure 180-300 ppmv levels of CO2, when the outside world is at 380 ppmv? If cracks (and drilling fluid) are found in the ice, that would show levels which were too high, compared to other neighbouring layers, never too low.
The formation of clathrates (solid forms of O2, N2 and CO2 with water at very cold temperatures and high pressure) depletes CO2 levels, according to Jaworowski. This is well known in the ice core world. Therefore they allow the ice cores to relax up to a year after drilling. Moreover: O2 and N2 clathrates would decompose first, thus escaping as first via microcracks (as Jaworowski alleges). This would lead to too high CO2 levels, not too low.
Jaworowski accuses Neftel of “arbitrary” shifting the Siple data with 83 years to match the ice core CO2 with the Mauna Loa data. But the page from Neftel’s report ( http://www.biokurs.de/treibhaus/180CO2/neftel82-85.pdf ) contains two columns in the table: the counted ice age and the calculated gas age, the latter based on porosity measurements of the firn. Jaworoski used the age of the ice, not of the air bubbles, to base his accusation on, which is quite remarkable for a specialist in these matters. CO2 is in the air, not in the ice and the average age of the gas is (much) younger than the ice where it is enclosed. Neftel even made specific remarks about the gas age, which was compared to the South Pole atmospheric data, to confirm the average age of the gas bubbles at depth:
If the 328 p.p.m. measured at a depth of 68.5 m.b.s. [note: meters below surface] is matched with the atmospheric South Pole record, the mean gas age is 10 yr, corresponding to a difference between mean gas age and ice age of 82 yr, which lies in the above estimated range. The difference is used in calculating the mean gas age for all depths.
That the CO2 concentration measured on the subsequent samples from 72.5 and 76.5 m.b.s. corresponds with the atmospheric South Pole record justifies this age determination…
This clearly indicates that Neftel based his gas age estimate on firm grounds and there is nothing arbitrary in “shifting” the data, as there was no shifting at all. Thus for the Siple ice core, the ice age – gas age difference is about 82 years (Neftel estimated 80-85 years) for an average gas age resolution of about 22 years in this case.
Many of the objections of Jaworowski were answered by Etheridge (already in 1996) by drilling three cores at Law Dome, with three drilling methods (wet and dry), using different materials for sampling, avoiding cracks and clathrates, allowing a lot of relaxation time and measuring the CO2 levels top down in firn and ice. No difference was found in CO2 levels between firn and ice at closing depth and there is an overlap of some 20 years of the ice core CO2 data with the South Pole data:
Figure from Etheridge e.a.: http://www.agu.org/pubs/crossref/1996/95JD03410.shtml
See more comment and further links about Jaworowski at:
http://www.ferdinand-engelbeen.be/klimaat/jaworowski.html
The “corrections” of J.J. Drake:
JJ Drake (http://homepage.ntlworld.com/jdrake/Questioning_Climate/userfiles/Ice-core_corrections_report_1.pdf ) claimed to have established that the CO2 levels needed a correction for the ice-gas age difference. The result of the “correction” is that the CO2 levels are much higher with little variation and the very good correlation with temperature vanished. This conflicts already with our knowledge of the influence of temperature on CO2 levels in current times…
Even so, the “correction” might be all right, but the reason he provided has no bearing in any physical relationship. He makes the basic mistake of conflating a good correlation with a causation: The error is of the kind:
A causes B and shows a good correlation.
A causes C and shows a good corelation.
Thus B causes C, because there is a good correlation between the two. But that correlation is completely spurious, as there is not the slightest physical connection between B and C.
The explanation for his observation is quite simple:
Temperature (“A”) causes the ice-gas age lag (“B”), as temperature is directly connected with humidity of the atmosphere, thus influences the amount of snowfall, thus the accumulation rate and as reciprocal the speed of closing the bubbles: higher temperature, higher snowfall, smaller ice-gas difference.
Temperature (“A”) influences CO2 levels (“C”) directly: higher temperature means higher CO2 levels.
Because the previous two results have a high correlation with temperature, that gives that the ice-gas age difference and the CO2 levels also show a high correlation, but there is no physical mechanism that shows any direct or indirect action of ice-gas age difference on CO2 levels or vice versa. It is a completely spurious correlation, without any causation involved, but both share the same cause. Any “correction” of CO2 levels found in ice cores based on the correlation with ice-gas age difference is meaningless.
Migration of CO2 in ice cores
Ice shows a thin layer of unstructured (liquid waterlike) water molecules near the surface of the air bubbles. Some CO2 may dissolve in this layer, but that is not a problem at measurement time, as measurements are made at low temperature under vacuum, effectively removing all CO2 from the opened bubbles in the crushed ice, while removing any water vapor as ice over an extra cold trap. Water in-between the ice crystals is very unlikely, as there is still the direct influence of ordered structural ice from both sides.
Migration in even the oldest cores is no real problem. The recent fuss about “migration” speed was deduced from the Siple core, based on layers where remelting occurred, something not seen in any high elevation ice core like Vostok or Dome C. It remains to be seen to what extent the Siple Dome results are applicable to other ice cores.
But if there was even the slightest migration of CO2, that would affect the ppmv/°C ratio of the above Vostok CO2/temperature graph over time: the proxy temperature indication is fixed in the ice, while CO2 is measured in the gas bubbles. If there was any substantial migration of CO2, the ratio between CO2 and temperature over warm and cold periods would fade away over the recurrent 100,000 years of time difference between the warm periods, but that is not observed.
Conclusion
The ice cores are a reliable source of knowledge of ancient atmospheres, if handled with care. The resolution heavily depends of the accumulation rate, with as result that the data measured in enclosed air bubbles are smoothed, ranging from 8 years for the past 150 years to near 600 years for the past 800,000 years.
Well, this may be true:
1. Conclusion
The ice cores are a reliable source of knowledge of ancient atmospheres, if handled with care. The resolution heavily depends of the accumulation rate, with as result that the data measured in enclosed air bubbles are smoothed, ranging from 8 years for the past 150 years to near 600 years for the past 800,000 years.
But it is true for the region where ice exists in a permanent form. So let us assume that we know what CO2 was and is at the icebergs. By construction where there are icebergs there is no vegetation an little organic CO2 even from neighboring oceans, due to the retention of CO2 by the cold water and the reluctance of green stuff to thrive at below zero temperatures.
The well mixed hypothesis is absolutely necessary in order to extrapolate CO2 content of the globe in time from ice cores. As I have said before, the CO2 measurements in latitude and longitude are so few and controlled by so few people, that it is foolish to think one has measured CO2 content of the world, particularly man made CO2, that is strong over cities, as Beck’s compilations have shown.
Satellite knowledge that is being filtered through the relentless AGW financial choke, still shows large variations of CO2 and questions well mixing. We should wait a few years of cooling, when purses will be opened for independent research on the CO2 subject before coming to any conclusions.
anna v says: (August 20, 2010 at 9:48 pm) Well, this may be true: …
An enlightening comment, Anna. Thank you.
Ferdinand Engelbeen has been arguing for some time that the observed increase of CO2 in the atmosphere is human made. Initially, my feeling was that this had not been properly established and that the increase would have been at least in part due to increasing (ocean) temperatures and/or the THC (Thermohaline Circulation), particularly in view of the generally accepted evidence that in the long term records CO2 concentrations lagged temperature by several hundred years . I have worked through the figures for both ocean temperature and THC in multiple ways, and am now satisfied that their contribution to atmospheric CO2 is small compared to fossil fuel emisions. I am not satisfied with my own findings, because they do nothing to explain the long term CO2 lag [does anyone have an explanation for it?], but they do lead me to accept that F.E. is correct. [Perhaps I should be more careful, and say “probably correct”, because my own amateur efforts may well be somewhat inadequate.]
Far more reliable than tree rings from bristlecones, which can differ due to soil, fertiliser, water and temperature conditions.
What other gases are found in the ice cores?
Any evidence for vulcanism in the past that would change the local atmospheric composition?
Geologists made the same mistakes prior to Mt. St. Helens, thinking that it took thousands of years to accumulate flows.
They soon found out just how rapidly things can happen.
What about empirical lab testing of the behavior of c02 trapping bubbles according to pressure?
“But how can they measure 180-300 ppmv levels of CO2, when the outside world is at 380 ppmv.”
Good question but there is a better one. Are the levels of CO2 in the air usually at or near 380 ppm at the drilling location at the time the drilling takes place ? We are considering very cold dry locations well away from natural CO2 sources.
“The formation of clathrates (solid forms of O2, N2 and CO2 with water at very cold temperatures and high pressure) depletes CO2 levels, according to Jaworowski. This is well known in the ice core world. Therefore they allow the ice cores to relax up to a year after drilling.”
How would allowing such “relaxation” reverse the earlier depletion ? Would the CO2 levels return to exactly those levels that originally obtained ?
I wonder how much of the natural CO2 level variation might be due to the ratio of animal resperation to plant resperation? Do plants predominate during the cold periods?
“the proxy temperature indication is fixed in the ice, while CO2 is measured in the gas bubbles. If there was any substantial migration of CO2, the ratio between CO2 and temperature over warm and cold periods would fade away over the recurrent 100,000 years of time difference between the warm periods, but that is not observed.”
Unless the proxy temperature indication changes over time as well. We already have one good illustration of unreliable temperature proxies in the form of those pine trees. An awful lot of this stuff is a leap of faith.
“I have worked through the figures for both ocean temperature and THC in multiple ways, and am now satisfied that their contribution to atmospheric CO2 is small compared to fossil fuel emisions.”
Then why the absence of any irregularities in the rising CO2 slope that correspond with irregularities in human CO2 emissions ? There should be such irregularities within a steadily increasing angle of curve but neither are present.
A long slow steady slope requires a long slow steady cause and that brings us back to the undoubted global temperature cycling from MWP to LIA to date.
It is possible to have volcanoes erupt causing lower earth temps with a high CO2 content in the air.
Even if we are responsible for some fraction of the CO2 found in the atmosphere today, the question remains… is CO2 really responsible for climate change?
Stephen Wilde has a very good point there.
All indications show human activity is growing in a non linear way.
How come then that CO2 measurements are showing a linear rising?
It just does not make sense.
In addition, I am still waiting fro the punch line of proof that CO2 is the cause of climate change, and not, say, the sun.
It seems a lot of energy is spent here on a none issue.
FTA: “Many respondents still are not convinced that the mass balance is a firm proof that the observed increase of CO2 in the atmosphere is human made.”
That’d be because it isn’t. Your argument was ad ignorantiam and very weak.
“That makes that the average smoothing of CO2 levels is about 8 years.”
A synonym for “smoothing” is “averaging”, whether of the “autoregressive” or “moving average” type, or combination therof. So, you are speculating on the average averaging which takes place. What are the poles and zeros? Where are the notches and where does it balloon? What, specifically, is the frequency response? You don’t know, do you?
The rest of this article is just so much hand-waving. Even if you can claim a match between measurements since 1958 and what the ice cores say, you still have to assume, or speculate on reasons why, the relationship extends back into the centuries past.
You can rationalize it all you want, and determine what you think is likely, but until you have traveled back in time and confirmed the readings, it really is nothing more than an hypothesis.
Stephen Wilde says:
August 20, 2010 at 10:35 pm
“Then why the absence of any irregularities in the rising CO2 slope that correspond with irregularities in human CO2 emissions ? There should be such irregularities within a steadily increasing angle of curve but neither are present.”
e_por says:
August 20, 2010 at 11:23 pm
“How come then that CO2 measurements are showing a linear rising?”
Yes! As I discussed with Joel here.
rbateman says:
August 20, 2010 at 10:14 pm
“Geologists made the same mistakes prior to Mt. St. Helens, thinking that it took thousands of years to accumulate flows. They soon found out just how rapidly things can happen.”
Exactly my point. Those of us who have to build actual working mechanisms know only too well that nature is pernicious, and you must expect the unexpected. You may think you have covered every base, only to find the game isn’t baseball. Without solid confirmation from experiment or use, everything on the drawing board is vaporware.
clathrates aside, what about the existence of water within ice at a large range of p/t?
not only that but ice itself is a FLUID and behaves very dynamically. Huge lakes exist under the ice and the water didnt just melt down the bottom. It flows through the ice. I totaly disagree that ice bubbles are a closed system. Ice cores are interesting and there is a lot too learn about climate science from them. But ice bubbles are not a record of the past atmosphere, they are only a relict from it. The geological record shows much higher CO2 in the past when climates were relatively cool. Fossil evidence such as stomatal indicies show much greater variation in CO2, which is more probable due to variability in volcanism.
@Ray says: August 20, 2010 at 11:01 pm
“Even if we are responsible for some fraction of the CO2 found in the atmosphere today, the question remains… is CO2 really responsible for climate change?”
Absolutely right.
OK, there is SOME evidence temperatures have risen over the last century.
There is a fair amount of evidence that the trace gas CO2 levels have risen over the last century.
There is solid evidence that mans’ CO2 emissions are by no means entirely responsible for the increase.
That still leaves us with the unanswered questions:-
Cause?
Effect?
Co-incidence?
“The ice cores are a reliable source of knowledge of ancient atmospheres”
The plants seems to disagree:
http://www.geocraft.com/WVFossils/stomata.html
Ferdinand Engelbeen, why the emphatic “either/or” when asking of the source of the excess CO2? Basic science says it is not an “either/or” question or source, colder water holds more dissolved CO2, warmth speeds up all chemical reactions including fixation AND liberation reactions concerning CO2 or any substance for that matter, the list goes on and on. So why the either/or? Does man burn all kinds of compounds which all release CO2, yes, but the question is still moot.
I read recently that there are approximately 30 major underground coal fires burning around the world that are known to be set by lightning where the coal intersects the surface, they will burn for decades with no real way to put them out, millions of tons of CO2 per year being ejected into the atmosphere. Would we have been better mining it and using the energy instead of the total waste as it now is. The peat fires burning in Russia today, man made or natural? If we mine the peat and burn it to gen electricity or heat homes are they then man made CO2 sources instead of letting them burn naturally? If we burn coal that may be the 31st natural coal fire is this man made? How about all of the natural gas that seeps from countless spots and cracks in the Earth around the world, some I have personally seen seeping here in central US fields through cracks, if we drill and extract the gas and relieve the pressure that is causing the seepage is that then man made CO2 but if we let it pass unburned to the atmosphere to naturally oxidize is it then natural CO2? See, the question is not so easily man-made or natural but more of a blend, especially if we find in the future that the sun had something to do with this small warming over the last few decades you seem to be addressing.
Some might not believe me above so here a true story. In college some buddies and I went to rent a house. We found a farm house, dirt cheap about two miles from town, $160 a month I think. I asked the realtor what the pipe sticking out of the ground was about ten yards from the porch and leading into the house. I said water? He said no sonny, over there, is your water well, that’s your gas well. Gas well? How much a month? He looked like I was crazy to even ask and said, it’s YOUR gas well, there’s no meter. You must be from the city. We passed it because of the two miles to campus but I still remember wishing we would have grabbed that one every time I wrote the checks for the utilities.
Your bubbles in the ice cores is interesting but I don’t find it very convincing. We have had good scientists over many decades in the past measuring CO2 and you and many like you find it hard to trust their work but you trust 100% bubbles in ice cores in Antarctica?
And what about the other gases in the bubbles? Bound to find methane right? How about the spontaneous hydrogen that any evacuated canister of glass, copper, steel that over time will have hydrogen found inside? How about the chemical reactions that these decade old bubbles go through. I don’t know, you don’t give enough information.
Most of the major scientific constants were known to three+ digits by the mid 1800’s by good scientists and everyone knows the number of digits has increased dramatically of late with the equipment we now have. Well, that is except gravity to five or six and I just wish we could honestly peg man’s influence on CO2 in it’s totality to two digits before I pass on, with all factors I mentioned above included.
You might think it’s all man’s CO2 but I still have doubts on that matter. Need more and better data to convince me. Do I think a portion is from mankind, of course.
Stephen Wilde wrote:
“Then why the absence of any irregularities in the rising CO2 slope that correspond with irregularities in human CO2 emissions ? There should be such irregularities within a steadily increasing angle of curve but neither are present.
A long slow steady slope requires a long slow steady cause and that brings us back to the undoubted global temperature cycling from MWP to LIA to date.”
Good point. But CO2 levels are also affected by biological activity hence the annual variability in the Mauna Loa measurements. Seasonal variation (temp and precip) affects biological activity. As has been pointed out here on many occasions, the earth’s climate system consists of myriad interwoven variables.
Having watched Ferdinand argue his case over a long time, I suspect that he is substantially correct. If Jaborowski wants to make his case, then he needs to perform some experiments demonstrating CO2 migration through the ice. Personally, I’m looking forward to the results of the million year core.
Actually there is evidence that the “smoothing” may be rather more of a problem than usually admitted, at least for older records. Measurement of CO2 from SOI (stomata) show rather sharp changes (50-100 ppm) at the beginning and end of the Younger Dryas (as might be expected) which are completely invisible in the ice-core record (ref e. g. Earth and Planetary Science Letters 213 (2003) 191-204).
There is also a unique sequence from Denmark through much of the last interglacial (http://www.geocraft.com/WVFossils/Reference_Docs/Last_interglacial_CO2_stomata_Rundgren_etal_2005.pdf)
which also indicates a much more variable CO2 concentration than the ice cores.
There is also a consistent tendency for the SOI measurements, irrespective of age to show moderately higher values (on the order of a few tens of ppm).
Also that 8 year figure for Law dome has always seemed quite implausible to me. Closure occurs when firn turns to ice, which happens at a depth of 90-100 meter. Surely there is not a 10+ meter-per-year accumulation rate at Law Dome? However there is another closure mechanism that may complicate matters in marginal areas of Antarctica. If there is a widespread melting event (which do happen in some parts of Antarctica), then the firn below the ice layer that forms on re-freezing will be effectively sealed from the atmosphere.
“But how can they measure 180-300 ppmv levels of CO2, when the outside world is at 380 ppmv?”
This is not entirely convincing. 380 ppmv is the average CCO2 level in the earth’s atmosphere, but it varies considerably from one location to another and may not have been the local level when the drilling was performed.
Ben says:
“Huge lakes exist under the ice and the water didnt just melt down the bottom. ”
In Antarctica it most certainly did. The subglacial lakes in interior Antarctica are caused by local geothermic basal melting of the ice. The ice above them is well below zero centigrade and has definitely been that way for 800,000 years, and probaly for several millions of year.
It seems funny to me that the Vostok ice core atmospheric CO2 level graph for the past 400,000 years shows CO2 levels below that which will sustain plant life. As far as I know plants have never had problems growing and reproducing, if they had we would not be here now. Another problem with this paper is that the annual global CO2 budget contains both natural and anthropomorphic productions. According to the US Dept. of Energy our bit of this is 3%. This is way below the errors accrued of the estimations of natural producers.
This paper also assumes that the theory of Greenhouse warming due to GHG’s is correct. The laws of thermodynamics show this theory to be false so CO2 is absolutely no problem.
You have still failed to answer one key point, do co2 levels at Antarctica represent the global level? I doubt it very much given the temperature of the oceans there, and recent satelite data has confirmed its not “well mixed” as was assumed. Can you comment regarding this argument? Is there any evidence that co2 levels at Antartica represent the global average at all times in history? Is they dont, they you cannot use it for mass balance without knowing its relation to global levels and at various times i.e. interglacial, and ice age. I doubt this is possible with any certainty – therefore, great uncertainty still exists.
Engelbeen states that “The spread in temperature/ CO2 data, mainly at the high side, is from the long lag of CO2 levels which remain high for thousands of years at the end of a warm period, while the temperature is dropping back to a minimum. ” In this statement, Engelbeen asserts that the data on which he is relying demonstrates that even as CO2 reaches a maximum, temperatures begin to fall. It is hard to imagine a more clear cut statement that whatever drives major climate changes in the last million plus years, it’s not CO2. Engelbeen’s other observation (not a new one either) – that increases in atmospheric CO2 concentrations lag temperature increases by 800 years – corroborates that conclusion from a somewhat different perspective. He believes that his data supports a conclusion that global temperatures begin increasing some 800 years before CO2 concentrations begin to increase. Even if we say that it is open to debate (because consensus does not rule) that human activities are increasing atmospheric CO2 concentrations, the issue is whether, and to what extent, the inquiry is really relevant if the evidence demonstrates that major climate shifts show no correlation with atmospheric CO2 concentrations.
anna v says:
August 20, 2010 at 9:48 pm
The well mixed hypothesis is absolutely necessary in order to extrapolate CO2 content of the globe in time from ice cores. As I have said before, the CO2 measurements in latitude and longitude are so few and controlled by so few people, that it is foolish to think one has measured CO2 content of the world, particularly man made CO2, that is strong over cities, as Beck’s compilations have shown.
The CO2 levels are measured by hundreds of people, from different countries working for different organisations. At some 70 places nowadays one measures “background” atmosphere + regular in-flight measurements, where there is little influence of local/regional sources and sinks and some 400 places are used to measure in/out fluxes of CO2 over land. Conclusion of this all (including the AIRS data): CO2 levels are well mixed within 2% of the range for 95% of the atmosphere within a year. Yearly averages are within 1% of the range. Only within the first 1,000 m over land, near huge sources (and sinks) there are huge diurnal and momentary variations.
Here the yearly averages for several “background” stations(cleaned from outliers, but that doesn’t change the yearly average with more than 0.1 ppmv), and one non-background station (Schauinsland), over 1,000 meters in the Black Forest (Germany):
http://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_trends.jpg
The conlusion of 50 years of measurements is that CO2 is well mixed if you stay away from huge sources and sinks. For the purpose of ice cores, that doesn’t even matter, as these are at least averaging over 8 years, up to some 600 years.
And please, NO discussion of Beck’s data here.
rbateman says:
August 20, 2010 at 10:14 pm
What other gases are found in the ice cores?
Many gases are found in ice cores, in general the same as found in the atmosphere, as the ancient air bubbles simply are enclosed in ice (with some exchanges with atmospheric air during compaction of the snow via firn to ice). See for the different measurements:
http://www.ncdc.noaa.gov/paleo/icecore/current.html
Where for e.g. the Vostok ice core several other items besides CO2 are measured:
http://www.ncdc.noaa.gov/paleo/icecore/antarctica/vostok/vostok_data.html
Volcanic events are found in ice cores, mostly as dust deposits and cause trouble in the Greenland ice cores, as the acid deposits of Icelandic volcanoes react with sea salt (carbonate) deposits and make CO2 in situ. That makes that the CO2 levels from Greenland ice cores are not reliable.
Stephen Wilde says:
August 20, 2010 at 10:21 pm
“But how can they measure 180-300 ppmv levels of CO2, when the outside world is at 380 ppmv.”
Good question but there is a better one. Are the levels of CO2 in the air usually at or near 380 ppm at the drilling location at the time the drilling takes place ? We are considering very cold dry locations well away from natural CO2 sources.
K. Andersen says:
August 21, 2010 at 1:25 am
This is not entirely convincing. 380 ppmv is the average CCO2 level in the earth’s atmosphere, but it varies considerably from one location to another and may not have been the local level when the drilling was performed.
The drilling of ice cores is quite recent: some of the oldest were in the 1980’s and the most recent after 2000. CO2 levels at the South Pole were measured since 1958 (even before Mauna Loa) and increased from 320 ppmv then via 340 ppmv in 1980 to 390 ppmv today. There is very little difference in ppmv’s between stations in the whole SH, thus including all drilling places.
The measurements in the different labs, in places on land, may even have much higher CO2 levels, and I don’t think the researchers hold their breath when preparing the samples (20,000 ppmv in exhaled air)…
tty says:
August 21, 2010 at 1:25 am
It is a coincidence that those lauding stomatal-based CO2 reconstructions seem not to have read Eide & Birks 2004.
Eide, W., Birks, H. H. 2004. Stomatal frequency of Betula pubescens and Pinus sylvestris shows no proportional relationship with atmospheric CO2 concentration. Nordic Journal of Botany, 24, 327 – 339. http://dx.doi.org/10.1111/j.1756-1051.2004.tb00848.x
Of course there is the issue of exteremophiles living in the ice changing the gas composition. “Some quantitative anomalies in the greenhouse gases CO2, CH4, and N2O have been attributed to microbial metabolism (40, 42), but this issue has not been yet experimentally addressed (30). ”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC321287/
A very interesting post. Thank you Ferdinand.
Ferdinand, what is your comment on this list here;
http://c3headlines.typepad.com/.a/6a010536b58035970c0120a5e507c9970c-pi
“If there was any substantial migration of CO2, the ratio between CO2 and temperature over warm and cold periods would fade away over the recurrent 100,000 years of time difference between the warm periods, but that is not observed.”
With the different characteristics of the ice layer…some layers being created during warm periods and other being created during colder periods it is possible to create a natural forward osmosis process with the differing layers of ice in which not only the concentration of the CO2 could be preserved but in fact the CO2 concentrations could be exaggerated. In other words the concentration of CO2 could be somewhat uniform through the ice but as time passes the differing layers allows H20 molecules to move yet keep the CO2 bubbles in the same place. Over time, like 800 years of time, the slight variations in CO2 concentrations could be exaggerated.
I am not going to say “I don’t believe” because that would be the religious solution but I do know there are far too many variables in the formation of ice to trust and one cannot say for certain it’s all human.
The trapping of gas in layers of snow is a very nebulus proposition. Variations of precipitation (both type and amounts), sublimation during long periods of sunshine, intra-daily temperature variations, atmospheric pressure variations, wind velocity, drifting snow and so on. Certainty there is not. OK so does human activity put CO² into the atmosphere? well of course it does. Do the oceans put CO² into the atmosphere? well of course they do. Do sink and source rates vary over time? Of course they do. Certainty, I think not.
John Marshall says:
August 21, 2010 at 1:36 am
I don’t know where you get your information from, but I would recommend trying to find a more reliable source.
“It seems funny to me that the Vostok ice core atmospheric CO2 level graph for the past 400,000 years shows CO2 levels below that which will sustain plant life.”
Either you think that CO2 levels fell to much lower levels than they did (~180ppm) or you haven’t looked at the experimental literature on the effect of low CO2 on plants. Low CO2 reduces growth rates, makes plants more stress sensitive and favours C4 plants over C3 plants, but plants can still grow. See for example, Ward et al. 2008 http://www.as.wvu.edu/~rthomas/publications/Ward2008.pdf
Campbell et al 2005 (http://www.ingentaconnect.com/content/bsc/gcb/2005/00000011/00000011/art00008) estimate that the compensation point (the level at which growth stops) for tobacco is below 100ppm.
“This paper also assumes that the theory of Greenhouse warming due to GHG’s is correct. The laws of thermodynamics show this theory to be false so CO2 is absolutely no problem.”
Which laws of thermodynamics would those be? Certainly not the real ones.
And please, NO discussion of Beck’s data here.
Why not?
And what about the pressure in the ice?
If the alternative hypothesis fails even only one of the observations, then the alternative is rejected.
Apparently, these rules do not apply to the theory of CAGW, only to “alternative” theories.
Ferdinand:
Your long article contains many contentious assertions and ignores several issues that you and I have debated over the years.
Perhaps the most important is that you gloss over a significant problem with the ice cores: viz.
liquid water exists on all surfaces of ice – including surfaces of ice crystals – at all temperatures down to -40deg.C.
This knowledge is not new. It was first discovered by Michael Faraday in 1859. Many recent studies have confirmed this and have determined the reason for it: simply, the molecular bonds of ice vibrate so break down near ice surface.
Hence, there is a 3D matrix of liquid water throughout the ice at temperatures above -40deg.C.
And gases dissolve in liquid water so they can diffuse throughout all ice at temperatures above -40deg.C whether or not the ice experiences bulk melting. Thus, ionic diffusion of gases occurs through the ice from regions of high concentration to regions of low concentration.
Therefore, it is not possible for the ice cores to indicate any high values of CO2 that existed millennia in the past, and it is not possible for bubbles in the gas to act as sealed canisters of the gas they enclose.
This is supported by the degree of adjustment the IPCC applied to ice core indications of atmospheric CO2 to provide them with agreement with the Mauna Loa data. The IPCC set the ‘ice age/gas age’ difference at 83 years to obtain that agreement.
However, as you say in your above article, Etheridge finds much shorter ‘ice age/gas age’ differences than 83 years.
And this causes a real problem.
If the IPCC adjustment of 83 years is an indication of diffusion (which seems likely) then all the ice core data has been smoothed by diffusion in similar manner to the conduct of an 83-year running mean.
Mauna Loa data has only been accumulated since 1958 (i.e. a total of 52 years) and, therefore, the 83-year diffusional smoothing in the ice would conceal any change in the atmospheric CO2 concentration similar to that observed at Mauna Loa.
And if the 83-year diffusional smoothing has not happened then how do you explain the findings of Etheridge which you report?
Richard
Richard S Courtney says:
August 21, 2010 at 4:29 am
Thus, ionic diffusion of gases occurs through the ice from regions of high concentration to regions of low concentration.
—————–
Yes, that would explain the ~100ppm difference between glacial and interglacial ice just 100 m apart.
Ferdinand Engelbeen says:
August 21, 2010 at 2:23 am
Only within the first 1,000 m over land, near huge sources (and sinks) there are huge diurnal and momentary variations.
Most of mankind, lives and burns fuels at less than 1000 meters over land. Most of the flora is at less than 1000 meters over land.
You consider 70 stations enough , and those far away from sources?
Why then don’t we measure temperatures in 70 locations far away from heat sources, like deep ravines and caves? That would surely give us the energy content of the globe.
The conlusion of 50 years of measurements is that CO2 is well mixed if you stay away from huge sources and sinks.
So would temperature be, if you stay away from the sun. Let us then only measure temperature at night at over 1000m.
It is incredible that the assumption of going away from the sources of CO2 will give a correct measure of the CO2 volume in the atmosphere is considered so self evident.
Like measuring smoke to estimate the BTUs of a fire.
The basic assumption made in this statement “Note that the ice cores only show CO2 levels back to about 800,000 years,” is that ice cores show what the atmospheric CO2 levels were with any accuracy further than two or three thousand years into the past.
As Richard S Courtney says there is diffusion of gases within the ice and the tendency would be for that diffusion to remove variance and end with a balanced concentration of CO2 in the ice layers. This has been measured and modeled.
Thus finding that other ice cores of similar age have similar concentrations is unsurprising and does not prove that the concentration of CO2 in the atmosphere when the firn formed was the concentration now found in the bubbles in the ice or that those values matched.
Given that the base assumption is flawed – the conclusions cannot be trusted.
“Even if we are responsible for some fraction of the CO2 found in the atmosphere today, the question remains… is CO2 really responsible for climate change?”
THAT is the question. Whether the CO2 increase is man made or natural is really secondary and not all that important. Really, its a distraction…
Stephen Wilde : “Then why the absence of any irregularities in the rising CO2 slope that correspond with irregularities in human CO2 emissions ? There should be such irregularities within a steadily increasing angle of curve but neither are present.”
A good question.
I made my point earlier rather briefly. I should elaborate a bit : When I said I thought F.E. was probably correct, I was referring to his conclusion that the observed increase of CO2 in the atmosphere is (mostly) human made, not to his reasoning. I have no opinion on his reasoning, having not worked through it to fully understand it.
What I did find was that I could not get anything like a match to the CO2 increase by trying to ascribe it to warming oceans, THC volumes, etc. I was therefore unable to contradict F.E.’s conclusion, and I felt that having done the work I should admit the result.
The incredibly close correlation between temperature (T not dT) and annual change in CO2 shows incontrovertibly (to my mind) that temperature affects CO2 levels. The same applies to the long term record (CO2 lagging by a few hundred years). It is also obvious IMHO that ENSO affects CO2 levels. But all the analyses that I did led me to the conclusion that although these factors did affect CO2, they could not explain the rise in CO2 over the last several decades – that in the absence of fossil fuel emissions, CO2 levels would still have risen but not by much. It is possible of course that I missed something.
Hopefully someone will answer your question eventually. I can’t.
http://www.jaxa.jp/press/2009/10/20091030_ibuki_e.html
The variation of the scale is evident in the CO2 plot and it is not 2% but closer to 10%.
Maybe Keeling et al ( all the Scripps publications of CO2) will get to them to trim their excess.
I’m just throwing this out here: There has been much debate as to the residence time of free CO2 in the atmosphere. This uncertainty would seem to cast doubt on the hypothesis that much of the C02 increase is manmade.
Well – but what’s cause and what’s effect?
From eyesight, using a straight edge to compare graphs, I think I see the CO2-graph LAGGING the temperature-graph over time, not LEADING.
Of course, it might only be an effect of my distorted eyesight.
But it might be something different, too.
Ferdinand Engelbeen… Thanks for your explanation of ice core data. I have read very little about it, so, again, thanks.
Two questions continue to bother me about AGW.
Why do CO2 graphs over long periods, trail temperature if CO2 is the primary cause of temperature change?
Why is 390 ppm CO2 vastly more important than 20,000 to 40,000 ppm H2O when CO2 is only 20 times more “active” than H2O in the greenhouse arena?
Has there ever research been done on the possibility, that water, especially cold water – like droplets in cold clouds close to the freezing point, for example, or cold ocean surfaces – might allow different gases (Oxygen, Nitrogen, CO2) to dissolve differently in the water?
Kind of a “qualified solution”, if you will.
Because, that might alter the ways, in which research on gases dissolved / stored in water/ice is conducted today, completely.
Nice article, Ferdinand.
Ben writes: “The geological record shows much higher CO2 in the past when climates were relatively cool. Fossil evidence such as stomatal indicies show much greater variation in CO2, which is more probable due to variability in volcanism.”
Besides the link posted above by richard telford, please note that Ferdinand pointed out that CO2 in ice is a direct measurement, which would be preferred over a proxy. It’s not that proxies are necessarily wrong, but do note that they need to be calibrated against direct measurements. That does imply that direct measurement is the standard, right?
And Martin Brumby wrote: “OK, there is SOME evidence temperatures have risen over the last century.
There is a fair amount of evidence that the trace gas CO2 levels have risen over the last century. ”
Glad to see you agree with the consensus on some basic points. You did forget the other important point, though, that CO2 is a greenhouse gas. 😉
Ferdinand Engelbeen says:
August 21, 2010 at 2:34 am
(…)
Volcanic events are found in ice cores, mostly as dust deposits and cause trouble in the Greenland ice cores, as the acid deposits of Icelandic volcanoes react with sea salt (carbonate) deposits and make CO2 in situ. That makes that the CO2 levels from Greenland ice cores are not reliable.
——————————————————–
That’s a whopper!
I didn’t know that. Here in Germany, ice cores from Greenland are sold to politicians and the public as the Holy Grail of climatology.
But now I read, their readings are absolute bogus?
Go figure…
Ferdinand Engelbeen… Background: As a Louisiana boy, with some background in geometry and other mathematics, I have spent a fair portion of my 60+ years around the 30 degree north latitude, altitude 100 feet, in 90+ degree temps and 90+ % humidity. Verifiable numbers impress me more than conjecture and speculation.
As we are burning 12 billion tonnes of coal and oil per year, why is there a question about the source of the 100 ppm of atmospheric CO2 that is out of the temperature-dependent equilibrium apparent in the ice-core record?
I love technical stuff like this. Shame what happens to good, solid, up to the minute science when a politician, a tinker, taylor, candlestick maker, or investment guru like Soros get their hands on it. Oh well… order and chaos, ying and yang!
There are plenty of samples of leaves and tree remnants to be found in the buried ancient river channels of California.
We found Alder leafs, pine needles and whole redwood/sequoia trees. A geologist from UC Berkeley came out to the Ruby Mine, Sierra County, in 1993 (Brush Creek Mining & Dev.) and got some sample we retrieved from the contact of the andesitic ash with the top of the gravels. We received word that they were approx 26M yrs old, but never any indication of stomata counts.
The particular location was under 1,000′ of andesitic breccia.
There ya go, geologists. There’s plenty of drifts in the Sierra that show the abundance of buried vegetation matter perfectly preserved. Go get it.
Since Ferdinand scored an F in mass balance calculations and his only response to my mathematical proof than the Anthropogenic component of the current atmosphere could not be greater than 18ppm, was that he could take no responsibility for the IPCC fig 7.3 which he agreed was substantially flawed and yet the values in the NASA numbers he quoted bore an eerie resemblance to the IPCC numbers.
Now we appear to have another substantial disconnect with the laws of physics relating to ice cores.
Ferdinand appears to support the concept that “air” bubbles exist in the deep glaciers , this is total nonsense since the great pressure which exists in the glaciers will drive ALL the gasses below a certain depth into solution.
With regards to the solubility of the major gasses, CO2 is 179.7 cc per 100 grams of water at 1 atm. At 0 deg C. O2 is 4.89 and N2 is 2.35. Now from these numbers Henrys constants can be determined which are consistent below 1 atm.
Henrys Law H=Pa/Xa clearly states that the solubility of a solute in a solvent is directly proportional to its partial pressure.
Now if we reduce an “air “bubble to 1/10th its volume by compression the gas components will go into solution in the ratio of their solubilities, bearing in mind as more CO2 enters solution its partial pressure relative to the other gasses will decrease so the absorption rate will be offset somewhat but the ratio of the CO2 to the other gasses will fall rapidly. Thus we no longer have the mythical “100 000” year old “air” trapped in the ice.
On a point of biology the IPCC curves show the CO2 levels dropping to an average of around 180 ppm ( this is probably a 1000 year average) if this was the case approximately 50% of all plant life would become extinct and what plants remained would be so poor that they could not support the herbivores etc. so there would have been mass extinctions which did not happen.
There are other much more reliable proxies than ice cores for determining CO2 content of the atmosphere such as leaf stomata and they disagree substantially with the ice core data.
I see J.J.Drake’s paper was mentioned I strongly recommend people read it, his method for determining the age of the ice verses the CO2 taken from the ice was to compare the O18/O16 ratio of both the CO2 and the water, he found up to a 7000 year difference and produced a very sound correction curve for the ice core data which makes sense.
I notice the subject of Calthrates was glossed over. The missing CO2 is trapped in the ice crystals as a Calthrates and cannot be extracted which explains why the CO2 levels are low.
Stephen Wilde says:
August 20, 2010 at 10:25 pm
“The formation of clathrates (solid forms of O2, N2 and CO2 with water at very cold temperatures and high pressure) depletes CO2 levels, according to Jaworowski. This is well known in the ice core world. Therefore they allow the ice cores to relax up to a year after drilling.”
How would allowing such “relaxation” reverse the earlier depletion ? Would the CO2 levels return to exactly those levels that originally obtained ?
The relaxation allows ice to expand slowly (at low temperatures, mostly on site under surface) to avoid cracks, but above the temperature that clathrates (de)compose. This is a (very) slow process, but when checks were done on ice that was completely sublimated (to ensure that no clathrates were left) and water again removed, the same CO2 levels were found as with the “cheese grating” technique. Moreover, it seems that the vacuum used to extract air/CO2 from the crushed ice is an effective means to decompose clathrates.
Just noting Ferdinand that the “8 ppmv/C” number is calculated using Antarctica’s temperature estimates which vary by twice as much as the global amount in the ice ages and in general. Antarctica has warmed 10C since the height of the ice age while the global value is assumed to be 5C.
So the 16 ppmv/C value is more accurate if one is using global or ocean water temperature changes.
Spector says:
August 20, 2010 at 10:30 pm
I wonder how much of the natural CO2 level variation might be due to the ratio of animal resperation to plant resperation? Do plants predominate during the cold periods?
Hardly any, as what animals respire has been captured some months/years before. Some carbon is temporarely stored in fat tissues, but that is very small, compared to what is stored in vegetation in general.
—
Isotopic analyses of atmospheric and ice core carbon compounds (including carbon dioxide) seems to have demonstrated that the increase in today’s atmospheric CO2 concentrations is the result of fossil petrochemicals combustion, emphasis on the burning of coal.
Is this not so?
If this is an acceptable conclusion, it has become impossible to deny that human action has made an impact upon the environment. But, then, what species on this planet has not made an impact on the environment? Blue-green algae, f’rinstance….
The question that requires answer is what might be the real climatological impact of anthropogenic atmospheric carbon dioxide concentration increase, and studies thus far have been so thoroughly indicative of a substantively nil effect that the CAGW high priesthood has been sweating and struggling for the past couple of decades to concertedly suppress the publication of observational studies demonstrating this reality.
The way I read it is simply that if there were no disproofs of the anthropogenic global warming hypothesis coming by way of reliable instrumental analytical work – such as those of Drs. Lindzen and Choi at MIT, for example – the CRU correspondents exposed last November wouldn’t have been striving to corrupt the peer review process and apply extortionate pressures upon the editors of professional publications in their areas of discipline.
It is not enough simply to say that atmospheric CO2 levels have increased. It must be demonstrated that such an increase has been (or possibly could be) causative of significant climate change, and in this the CAGW fraudsters have repeatedly and spectacularly failed.
—
Stephen Wilde says:
August 20, 2010 at 10:30 pm
“the proxy temperature indication is fixed in the ice, while CO2 is measured in the gas bubbles. If there was any substantial migration of CO2, the ratio between CO2 and temperature over warm and cold periods would fade away over the recurrent 100,000 years of time difference between the warm periods, but that is not observed.”
Unless the proxy temperature indication changes over time as well. We already have one good illustration of unreliable temperature proxies in the form of those pine trees. An awful lot of this stuff is a leap of faith.
That would mean two effects: temperature and CO2 peaks and sinks differences would fade away over each period by itself and both must show identical fading. Which is rather unlikely because they reside in different media.
While I am not entirely convinced by Ferdinand’s argument, I must say I appreciate the tone and williness to engage with those of us that remain skeptical but open minded. I can think of a dozen questions I would need answers to for ice core measurements to be more convincing of their accuracy, but in the end I agree that CO2 concentrations in the atmosphere are increasing, at least partly due to human activities.
The real question is what is the impact? The ice cores seem to indicate that CO2 rises occur naturally and that there is no “run-away” global warming. The fact that CO2 lags temperature rises would still indicate to me that CO2 has little impact.
Ray says:
August 20, 2010 at 11:01 pm
Even if we are responsible for some fraction of the CO2 found in the atmosphere today, the question remains… is CO2 really responsible for climate change?
In my opinion we are responsible for the full increase in the atmosphere (see the previous discussion), but that says nothing about the effect of the increase. But that is not the topic here…
I have two problems with ice core data:
1. Ice crystals grow over time. Eventually, the ice crystals will grow larger than the ice core diameter. As ice crystals grow the grain boundaries sweep impurities, including bubbles, away. What does this do to the measurements? This is never mentioned.
2. I have doubts about measurements below 200 ppm. Photosynthesis begins to shut down at those levels. Wouldn’t rotting vegetation hold the CO2 level above 200 ppm?
e_por says:
August 20, 2010 at 11:23 pm
All indications show human activity is growing in a non linear way.
How come then that CO2 measurements are showing a linear rising?
It just does not make sense.
Both the human emissions and the increase in the atmosphere are increasing slightly eponential, and the increase in the atmosphere follows the totallity of the emissions with an incredible fixed ratio:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_co2_acc_1900_2004.jpg
and
http://www.ferdinand-engelbeen.be/klimaat/klim_img/acc_co2_1900_2004.jpg
In addition, I am still waiting fro the punch line of proof that CO2 is the cause of climate change, and not, say, the sun.
It seems a lot of energy is spent here on a none issue.
My fear is that too many skeptics are defending the undefendable: that humans are not the cause of the rise. That is a point where the “consensus” is rock solid. That undermines their credibility on other points where the “consensus” is far from certain.
I love this site!! When I saw the title of this article, I thought back to the question of CO2 diffusion in ice brought up by another poster. The point about bio-transformation of the CO2 and/or organic matter trapped in the ice is also a good one. What with thousands of years to operate, these mechanisms could come into play. The climate scientists are too quick to come to a conclusion and don’t spend nearly enough time trying to shoot down their own hypotheses. It’s a pity this sort of thing has to be pointed out on a blog on the internet rather than in scientific journals.
It’s an incontrovertible fact that humans are transforming organic compounds to CO2. But the real question remains: does it matter?
Question: When glacier ice melts (with some evaporation and sublimation) what happens to the gas trapped within? Does it mostly go into the runoff and hence the ocean or does much move into the atmosphere? If the latter, there should be rapid concentration increases of CO2 in the atmosphere at the times of rapid de-glaciation.
Bart says:
August 20, 2010 at 11:55 pm
FTA: “Many respondents still are not convinced that the mass balance is a firm proof that the observed increase of CO2 in the atmosphere is human made.”
That’d be because it isn’t. Your argument was ad ignorantiam and very weak.
That is your opinion, mine is that you can’t create carbon from nothing, and if humans add twice what is seen as increase in the atmosphere, the nature must be a net sink and isn’t contributing to the rise. But that is for the other discussion.
A synonym for “smoothing” is “averaging”, whether of the “autoregressive” or “moving average” type, or combination therof. So, you are speculating on the average averaging which takes place. What are the poles and zeros? Where are the notches and where does it balloon? What, specifically, is the frequency response? You don’t know, do you?
No I don’t know, as I don’t have the possibility to know it (retired) and my knowledge on that is very rusty. But Etheridge e.a. have calculated it and you can see the curve for a one-time pulse of CO2 in the same ice core at:
http://courses.washington.edu/proxies/GHG.pdf
The rest of this article is just so much hand-waving. Even if you can claim a match between measurements since 1958 and what the ice cores say, you still have to assume, or speculate on reasons why, the relationship extends back into the centuries past.
Of course, one is never sure of the past, but one can be more sure from some proxies than of others. There is an overlap of some 20 years with the direct measurements and overlapping periods between different ice cores over longer periods, which show similar CO2 levels for the same average gas age, even if the ice was formed under very different circumstances, that increases the confidence level.
You can rationalize it all you want, and determine what you think is likely, but until you have traveled back in time and confirmed the readings, it really is nothing more than an hypothesis.
***************************
Ferdinand Engelbeen says:
August 21, 2010 at 7:55 am
Bart says:
August 20, 2010 at 11:55 pm
Of course, one is never sure of the past, but one can be more sure from some proxies than of others. There is an overlap of some 20 years with the direct measurements and overlapping periods between different ice cores over longer periods, which show similar CO2 levels for the same average gas age, even if the ice was formed under very different circumstances, that increases the confidence level.
**********
If there exists a mechanism that allow CO2 to diffuse in ice, that would not manifest itself in the 20 years of instrumental measurements. More study is required. Also, any organic matter trapped in the ice could be converted to CO2 or carbonate to organic matter. At colder temps, this could be a slow biological process.
In the Jim @ August 21, 2010 at 8:05 am, I intended to indicate a mechanism of CO2 diffusion that takes hundreds or thousands of years to operate, not just one that operates over months or even years.
Rich Matarese wrote, “The way I read it is simply that if there were no disproofs of the anthropogenic global warming hypothesis coming by way of reliable instrumental analytical work – such as those of Drs. Lindzen and Choi at MIT, for example…”
Climate sensitivity is the real key here, isn’t it? This is beyond the scope of the current article, and as Ferdinand noted, “In my opinion we are responsible for the full increase in the atmosphere (see the previous discussion), but that says nothing about the effect of the increase.” Not accepting what is overwhelming evidence (along with using terms like “CAGW high priesthood”) does your side little good, and makes it much easier to dismiss arguments.
You also might want to be careful putting too may eggs in the Lindzen-Choi basket. Dr. Spencer outlined some major criticisms on these pages, and so did Judith Curry at DotEarth. Not to mention the rebuttal by Trenberth, et al. published in GRL.
Anthropogenic or natural, any; the carbon dioxide is good for life and it doesn’t cause any change on climate.
The carbon dioxide is not a blackbody and its absorptivity and emissivity at its current conditions are negligible, 0.0017, if we consider its partial pressure and temperature, and 0.0042 if we take into account the mean free path length of photons.
The time a molecule of carbon dioxide can “store” thermal energy is extremely low, of the order of 20 + – 5 attoseconds. So it is a good coolant of the atmosphere, not a warmer.
Conclusion, it doesn’t matter whether the carbon dioxide is emitted by humans or by nature. It doesn’t cause any global warming either climate change because its physical properties regarding thermal energy exchange are negligible.
Michael Schaefer says:
August 21, 2010 at 5:52 am
Volcanic events are found in ice cores, mostly as dust deposits and cause trouble in the Greenland ice cores, as the acid deposits of Icelandic volcanoes react with sea salt (carbonate) deposits and make CO2 in situ. That makes that the CO2 levels from Greenland ice cores are not reliable.
——————————————————–
That’s a whopper!
I didn’t know that. Here in Germany, ice cores from Greenland are sold to politicians and the public as the Holy Grail of climatology.
But now I read, their readings are absolute bogus?
—————
Only in your dreams. It’s probably a couple of decades since anyone tried measuring CO2 from Greenland ice cores, because it was realised that dust in them was reacting with acid to contaminate the signal. But that doesn’t contaminate any of the other proxies – deuterium, oxygen isotopes, conductivity, sulphates, dust, methane, gas isotopes, etc. The Greenland ice cores are one of the best archives we have.
Ben says:
August 21, 2010 at 12:06 am
clathrates aside, what about the existence of water within ice at a large range of p/t?
not only that but ice itself is a FLUID and behaves very dynamically. Huge lakes exist under the ice and the water didnt just melt down the bottom. It flows through the ice. I totaly disagree that ice bubbles are a closed system. Ice cores are interesting and there is a lot too learn about climate science from them. But ice bubbles are not a record of the past atmosphere, they are only a relict from it. The geological record shows much higher CO2 in the past when climates were relatively cool. Fossil evidence such as stomatal indicies show much greater variation in CO2, which is more probable due to variability in volcanism.
A lot of allegations, some true, most not. Waterlike structures exist at the top layers of the border between ice and air, because air doesn’t show a forcing on the water molecules like the orderly structure of the ice crystal itself, which increases in disorder towards the air (if I remember well, some 5 molecules thick at low temperature). Not in between the ice crystals, where the ice layer has deformities, but both crystals still exert enough attraction on the intermediate molecules from both sides. This is seen under an electronmicroscope. Unfortunately I have lost the original reference to that article, but that there is no liquid water in between to hide the CO2, as Jaworowski says is seriously rebutted here:
http://www.someareboojums.org/blog/?p=17
Below -2 C there is probably no liquid water between the ice crystals, as measured by dielectric permittivity:
http://jeeg.geoscienceworld.org/cgi/content/abstract/12/1/37
The rest of your discours may be true for near-meltpoint mountain ice cores, but certainly not for most Antarctic ice cores, where temperatures are much lower.
Btw, glass is also a “liquid”, but I don’t think that there is much migration of gases through glass…
wayne says:
August 21, 2010 at 12:37 am
“Ferdinand Engelbeen, why the emphatic “either/or” when asking of the source of the excess CO2? Basic science says it is not an “either/or” question or source, colder water holds more dissolved CO2, warmth speeds up all chemical reactions including fixation AND liberation reactions concerning CO2 or any substance for that matter, the list goes on and on. So why the either/or? Does man burn all kinds of compounds which all release CO2, yes, but the question is still moot.
I read recently that there are approximately 30 major underground coal fires burning around the world that are known to be set by lightning where the coal intersects the surface, they will burn for decades with no real way to put them out, millions of tons of CO2 per year being ejected into the atmosphere..”
There is also ample geologic evidence, as seen in the scoria rock formations, of such naturally caused underground coal fires having been a regular happening, geologically speaking. Just one of the many potential variables that are unknown in the equation. Many, many leaps of faith in this paper with all the standard implied causality one should not use in scientific analyses.
Ferdinand as always puts a compelling case. And yet…And yet…
For those interested in the history of Co2 readings-which date back to 1820- I wrote this article which appeared on TAV
http://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/#comment-34865
It attracted hundeds of comments and since then there have been a number of other threads which I have linked to. The comments and the links make fascinating reading and if you want to know the history and the detailed science arguements from both sides of the fence it provides a considerable resource.
I have two main concerns.
The first is that historic readings are so comprehensively dismissed as inaccurate. Yet taking Co2 measurements is a science that has developed from 1820 and was practised by literally hundreds of highly competent-indeed internationally known- scientists. Can their hundreds of thousands of reading taken over 130 years ALL have been wrong?
There remain a number of doubts in my mind which neither Ferdinand- nor any of the other highly competent commenters- have ever answered to my complete satisfaction;
* How come we were able to split the atom yet were still not able to accurately determine the composition of our atmosphere?
* How was Charles Keeling-a novice in these matters- able to instantly come up with the highly accurate readings that we are asked to believe completely eluded his more illustrious (at the time) predecessors for over a century?
* Why were Keelings readings in acordance with the research by Callendar which can be clearly seen to have been cherry picked to tie in with his own AGW theory-which was comprehensively dismissed at the time?
* Is the highly complex business of analysing ice cores foolproof and do they therefore definitively prove that our Co2 concentration had not changed until the industrial age?
I don’t pretend to have the answers. I remain uneasy that such a huge body of (apparently) reputable science is so routinely dismissed, as history shows us that taking Co2 readings was a matter of routine throughout much of the 19th century.
Ferdinand may be right-I can’t say with certainty either way-but I do know I would feel more at ease if the numerous records of historic CO2 readings were independently analysed so this can be laid to rest once and for all.
Incidentally, Ferdinands views on whether increased Co2 concentration materially affects our climate appears to be surprisingly nuanced and an additional article on his thoughts on this aspect would be illuminating.
Tonyb
wayne says:
August 21, 2010 at 12:37 am
Long story, but here a short answer on:
Your bubbles in the ice cores is interesting but I don’t find it very convincing. We have had good scientists over many decades in the past measuring CO2 and you and many like you find it hard to trust their work but you trust 100% bubbles in ice cores in Antarctica?
The scientists from the past were good with the means they had at that time. Accuracy of atmospheric measurements typically +/- 10 ppmv. Differences between two measurements (same place, diurnal or sometimes with only 15 minutes in between): several hundreds of ppmv’s. Main problem: wrong place where measured (near huge sources and sinks).
Accuracy of ice cores with today’s technique +/-1.2 ppmv (one sigma, same ice core). +/- 5 ppmv between largely different ice cores for same gas age.
Thank you Mr. Courtenay, exactly a point I wanted to make.
It is also not believable that current atmospheric CO2 concentrations can diffuse 10s of meters into increasingly compressed snow. Also ice cores, stored to allow relaxation, are not stored at extreme temperatures (<-40)C, so can also allow out diffusion. Depressurization and out diffusion probably takes place down to some fairly constant level at one standard atmosphere, regardless of initial concentration. Also there is some fractonation prior to fern closure, small but some. Combining these factors, with the smoothing from long closure times means that we simply don't know what short term variations (the last 100 years of fairly fast CO2 concentration change is a fairly short time) in CO2 concentration may have taken place in the past. There could have been substantial spikes as suggested by some stomata studies, that are simply smoothed out.
While Beck is forbidden it is clear even from the selected data accepted from his whole cited data bank, that atmospheric CO2 ca 1780 was at least 20 ppm higher than suggested by ice core data, and probably near 10 ppm of the increase since then has been due to warming, so the actual anthropogenic increase is almost certainly near 30% less than usually stated.
I agree with Mr, Englebeen that the bulk of the increase in the last 2 centuries is man made, but disagree that the ice cores are a good reflection of past concentrations.
John Silver says:
August 21, 2010 at 12:35 am
“The ice cores are a reliable source of knowledge of ancient atmospheres”
The plants seems to disagree:
http://www.geocraft.com/WVFossils/stomata.html
Stomata data are calibrated over the past century… against ice cores and direct measurements. And they have their own problems: they react on CO2 levels of the previous year, which are by definition on land near other huge sources/sinks. Which may change over time (and with climate) for types of plants, land use changes, ocean currents (LIA!), wind direction…
Englebert,
reading ice cores is the modern equivalent of reading chicken gizzards and other less savory practices. Get over it.
The old saw that extraordinary claims require extraordinary proof should have a couple of corollaries:
1. claims that run counter to common sense require extraordinary proof
2. claims that support secondary gain for the presenter require extraordinary proof.
In the case of atmospheric CO2 and human emissions #1 above is partly invoked (I am not invoking #2 in this posting; I do not think it is an issue here). If it is true that human CO2 production is only 4% of total production, then common sense indicates that a relatively small change in the other 96% (which must be biological, for the most part) could overwhelm any human change. For example a few percent change in CO2 production from the huge reservoirs of biologically available carbon (rotting vegetation, peat, coal, oil seeps, etc) could produce big changes in the overall flows in the Earth’s CO2 cycle.
The huge increases in CO2 during some interglacials in the past came from somewhere, as yet not known with certainty.
So long as these sorts of issues remain, the truth about effects of human production of CO2 should be considered as in some doubt.
tty says:
August 21, 2010 at 1:25 am
(The stomata data is for part 3, but I did give already a short reaction)
Also that 8 year figure for Law dome has always seemed quite implausible to me. Closure occurs when firn turns to ice, which happens at a depth of 90-100 meter. Surely there is not a 10+ meter-per-year accumulation rate at Law Dome? However there is another closure mechanism that may complicate matters in marginal areas of Antarctica. If there is a widespread melting event (which do happen in some parts of Antarctica), then the firn below the ice layer that forms on re-freezing will be effectively sealed from the atmosphere.
There is about 1.2 meters ice equivalent precipitation at Law Dome summit.
Until the layers are dense enough (eventually by summer melt), there are exchanges with the atmosphere. As we have nowadays a change in atmospheric CO2 levels (monotone increase), one can compare the CO2 levels at sealing depth) with those of the atmosphere, which shows only 7 years difference for the Law Dome ice cores, 10 years for Siple Dome, etc… That makes that the ice age – gas age difference is 30 years for Law Dome and some 80-85 years for Siple Dome.
According to Etheridge e.a. most of the air at sealing depth is from diffusion and very little from advection to the ice. Thus one may use the air age as is at that point.
The averaging is mostly from the time needed for full sealing of the bubbles, which is about 8 years for Law Dome, as these contains bubbles which were closed in different sealing periods.
I don’t think there’s any doubt we’ve contributed CO2 to the atmosphere and that any ‘extra’ should be attributed to our activities.
I also don’t think that a scatter plot is a useful mechanism to portray chronological data. Without knowing how each point on the plot was trending, we can’t decide if the variability in the CO2 causes the variability in the temperature record based on this plot. Scatter plots are useful for trending such variables as mortality rate versus toxicity levels, but not for showing a relationship between chronological data points.
What we can see from the scatter plot is that there appears to be no reliable relationship between temperature and CO2. Look at the variability along the T = -6 and T = -4 lines. Clearly a wide range of CO2 concentrations existed for those two temperature points, and without seeing the trend, I have to find that a doubling of CO2 does not raise temperature by 2 degrees. Along T = -6, the amount of CO2 seems to vary between 200 ppmv and 265 ppmv. (take the ratio whichever direction you want, I read enough bickering about it a couple posts ago) Along T = (about) -4, the CO2 concentration seems to vary between 190 ppmv to about 272 ppmv.
What do we get from the chronological data? We do see an apparent relationship between CO2 and temperatures, we see that there is a lag between the two. How is the lag explained by the climate modelers? Well, we have the explanation that the gasses escape from between the ice crystals until sufficient pressure makes that escape impossible.
I accept that, it’s really a good explanation. However, narrowing down when the pressure seals the gasses within the ice is very difficult to say with any certainty.
The statement is made that Al Gore “forgot to tell his audience that the CO2 levels lagged by some 800 years during a deglaciation and many thousands of years at the onset of new glaciations”. This statement seems apologetic to me. I would wonder if the theory of sealing gasses in the ice cores was well established prior to the drilling of the first ice core, or if the theory was developed afterward to explain away the apparent non-fit of the observed data to the climate theories? I expect the latter is true.
When the pressure would have sealed the gasses depends on (as stated in the post) how much snow falls during what period of time. It is the compressive weight of snow that seals the gasses, all very good and reasonable. However, the statement that during colder times there would be less humidity and therefore less precipitation and therefore less snow in a given area is unsupportable. I agree that colder temperature would produce less humidity and therefore less precipitation for water sealed in a lab flask. In the real world though, weather systems drive precipitation around the world, regardless of the temperature at Vostok or the Law Dome, regional or global weather patterns could certainly deliver more precipitation to the area. Freak snow storms occur.
Here is another paper behind many of the ideas in this post: http://www.scienceonline.org/cgi/content/abstract/317/5839/793 (requires registration)
Here is a statement given by the authors regarding their conclusions: “Experiments performed with an atmospheric general circulation model including water isotopes support [the paper’s] temperature interpretation.”
Modeling past weather is of course impossible. We cannot say with any certainly exactly how much snow fell over a given period of time in a specific location thousands of years ago. We therefore have no reliable method for judging how much gas escape to attribute to each slice of the ice core, and therefore how to ‘correct’ the data. I recognize that we can date modern ice by the signature of recent volcanoes, but we’re talking about ice cores dating back hundreds of thousands of years where the time for volcanic eruption includes error bars that exceed the lag time between CO2 and temperature.
Occam’s razor leaves me with one conclusion: the main driver of temperatures on the Earth is the Sun and the reason that temperature and CO2 seem related but off by varying amounts of time is that the amounts of plants and animals increase under good conditions and decrease under poor conditions, in addition to the heat and gas exchanges occurring between the atmosphere and the oceans. CO2 and temperatures are generally related to one another through solar activity and biomass, with periodic disruptions in the relationship caused by volcanoes, meteor strikes, earthquakes, forest fires, and other natural occurrences. The relationship is impossible to predict or model with any degree of certainty.
John Marshall says:
August 21, 2010 at 1:36 am
It seems funny to me that the Vostok ice core atmospheric CO2 level graph for the past 400,000 years shows CO2 levels below that which will sustain plant life. As far as I know plants have never had problems growing and reproducing, if they had we would not be here now.
Plants probably didn’t starve, because CO2 levels over land tend to be average 30-50 ppmv higher than “background” CO2 levels.
Another problem with this paper is that the annual global CO2 budget contains both natural and anthropomorphic productions. According to the US Dept. of Energy our bit of this is 3%. This is way below the errors accrued of the estimations of natural producers.
Wrong topic, see the previous discussion in part 1.
This paper also assumes that the theory of Greenhouse warming due to GHG’s is correct. The laws of thermodynamics show this theory to be false so CO2 is absolutely no problem.
This paper doesn’t assume anything of that kind, as that is a complete separate item.
Nature loves hysteresis. Why would anyone expect the processes involved with entombing CO2 in ice cores to conveniently reverse themselves in exactly the opposite fashion when CO2 is released? It cannot be that simple to expect CO2 measurements upon their release from the cores to reflect what they measured when they went in. If only things were that simple.
I collect old bottles and canning jars. One can see bubbles in the glass. Has anyone done CO2 measurements on these? – or would the glass-making environment skew the amount?
REPLY: well think about it, fire, factory, city…
-Anthony
Ferdinand,
The problem with Jonathan Drake’s analysis is that he ignores the rate of accumulation as the cause of the variation in the difference between gas age and ice age. Since the rate of accumulation is a strong function of temperature, there will be a correlation between temperature and the difference in gas age and ice age that is completely independent of the CO2 level. The rate of accumulation can be determined fairly well in the last cycle in the Vostok core by looking at the layer thickness vs. time. For the deeper parts of the core, the layers have been thinned out by pressure and the uncorrected variation is much smaller (see this plot of accumulation rate in m/year and Ice age Gas age Difference (IGD)). In keeping with my contention that irony always increases, Drake has the statement “Correlation is Not Causation” in the banner at the top of his home page.
For a different take on the ice core data read http://www.kidswincom.net/climate.pdf and decide which is more consistent with physics and real world observations. Pay attention to what happens when you use the CO2 measurements with their relationship to estimated temperatures to predict temperatures to the present. The relationship holds up until about 4000 BC. after that you get a nice hockey stick that gives you unrealistically high temperatures in the last century. Something changes the CO2 at pressures and temperatures at these depths.
We are considering very cold dry locations well away from natural CO2 sources.
About one fifth of the world’s volcanoes are between 10°S and the South Pole.
http://www.volcano.si.edu/world/volcanocriteria.cfm
My CO2 Hoax Alarm is buzzing!
Cutting right to the chase: Regardless the CO2 content of the current atmosphere, it has been shown repeatedly —in the geological record— that in almost every instance of CO2 rise or fall, atmospheric heat preceded those changes.
Well, if the CO2 increased after a temperature increase in the geological past, it had to have come from someplace, and if it consonantly fell when the temperature fell, then it had to have gone someplace.
Does it really make any difference from whence the CO2 doth arrive?
That horse is dead, it’s carcass having long since been absconded with by the denizens of the night.
It therefore seems as though some people are flogging the ground under which the dead horse once lay.
In closing, allow me a neat bit of sarcasm: It’s all those scientists whom are drilling all those holes and releasing all that trapped CO2 back into the atmosphere that are the cause of the increased CO2 we currently experience …
:o)
Re: Ferdinand Engelbeen says:
August 21, 2010 at 8:26 am
You said: “Waterlike structures exist at the top layers of the border between ice and air, because air doesn’t show a forcing on the water molecules like the orderly structure of the ice crystal itself, which increases in disorder towards the air (if I remember well, some 5 molecules thick at low temperature). Not in between the ice crystals, where the ice layer has deformities, but both crystals still exert enough attraction on the intermediate molecules from both sides. ”
But there is liquid water between the ice crystals. The reason why is that the water is highly acidic (>1M).
http://www.nature.com/nature/journal/v331/n6153/abs/331247a0.html#more_articles
This has been demonstrated by others as well.
bushy says:
August 21, 2010 at 3:13 am
Of course there is the issue of exteremophiles living in the ice changing the gas composition. “Some quantitative anomalies in the greenhouse gases CO2, CH4, and N2O have been attributed to microbial metabolism (40, 42), but this issue has not been yet experimentally addressed (30). ”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC321287/
The link you provided is from the last meters of a Greenland ice core, where organic material was found of some 120,000 years ago, that was genetically analysed and shows relationships with plants now found in Northern Canada. That has nothing to do with what is found in the rest of the ice core.
But there are algues and microbes found in ice. Algues produce oxygen and use CO2 as long as there is sufficient sunlight, but algues are more prevalent near the coast.
Some bacteria can survive even the extreme long period en temperatures where they are enclosed in the Vostok ice core. Survive is all they can, and they use N2O and CO2 for DNA repair. The maximum is about 0.1 ppmv CO2, if we assume that they use all available N2O as energy source in a ratio of 40:1 to CO2. See section K in:
http://www.pnas.org/content/101/13/4631.full.pdf
I would like to see a phase-space plot.
How much C02 is dissolved in the snow as it falls?
What are the effects of organisms living on the surface of the ice? In aquatic ecosystems, nutrients tend to be transported to the surface of deposits.
Has anyone determined the mobility of CO2 in ice over temp and delta pressure?
This statement, made just above the CO2/Temperature graphs makes me curious.
“The visual correlation between temperature and CO2 levels in ice cores is well known to everybody, as that was used by Al Gore and many others, although he forgot to tell his audience that the CO2 levels lagged by some 800 years during a deglaciation and many thousands of years at the onset of new glaciations:”
In what way is there a lag during deglaciation? Is the CO2 still coming down at that point as temperatures rise, or is it at its low point but stays there for hundreds of years before starting to rise again?
Similarly, if CO2 lags by thousands of years at the onset of new glaciations, what is causing the temperature declines? If it is the CO2, it would be a leading indicator, not a lagging one. If the CO2 remains high well after temps drop, it would be hard to blame it for the high temperature in the first place, would it not? Obviously the CO2 isn’t holding the energy in anymore, so I’d think it would be hard to argue that increases now are making things warmer. If the CO2 were responsible, we’d have an equilibrium, not a new ice age. Personally, I blame the sun, not to mention I think warm is better for the world than cold.
A few people have commented on plants shutting down at low CO2 levels. Are there any natural, but non-biological or non-plant processes that reduce atmospheric CO2?
We know roughly how much CO2 we’re putting into the atmosphere because we know how much is used because we need to know for measuring economic issues. So what is the rough, ballpark amount that we’ve put into the atmosphere in the last 150 years? And then how does that compare with the total volume of the atmosphere and the measured increase in CO2?
I know we put CO2 into the atmosphere, but do we put all of it in? Since CO2 has lagged temps for hundreds of thousands of years through many cycles, humans weren’t involved in previous cycles. The increases had to be due to other things like amounts dissolved in the oceans coming out of solution and other processes. So if anyone wants to take a shot at these questions, I’d appreciate answers.
Oh, and I very much appreciate this post as it was very informative. Thanks Mr. Ferdinand Engelbeen. I also appreciate the comments too. This was a very informative discussion.
“misconceptions which fly around on the Internet, mainly on skeptic blogs…”
Dr FE, I find this offensive and moreover the probability is that a thorough analysis of the blogs would find misconceptions more rife in the “consensus” blogs where they don’t have the advantage of cleaning and polishing that a truly open blog like WUWT , that allows such as yourself a space to make your case. Like the Chinese government, the consensus blogs don’t allow “misconceptions” to get aired and therefore, like the Chinese government, weeding out misconceptions keeps the party-line on the straight and narrow. I think an apology is in order.
Tell me you didn’t find any thought-provoking issues on the subject raised here by a throng of intelligent, international, talented scientists and amateurs. At WUWT, you can come as you are but you will go away different (to steal a jingle from the State of Louisiana’s tourist bureau.). You just have to look at the great pains that such blogs as the “misonceptions-free” Real Climate and Climate Progress take to try to rebut material that appears on WUWT. Why would they do that?
A little point on the ice core stuff: I believe an interesting proposition has been framed by the many excellent ideas by posters here. Experiment. Here is a gift for you. Design a series of experiments with ice, artificial atmospheres, bubbles, pressure, temperature, solubility of the gasses in water, ice, differential diffusion of the gases through ice (heck elements in hydrothermal fluids in solid rock diffuse from cracks into the uncracked wall rock – frozen water is highly likely more welcoming – I’m suspicious of the long term apparent stability of level of CO2 gleaned from ice cores). Also, another poster mentioned the Oxygen isotope ratios in the CO2 itself – this seems to me a natural line of inquiry for anyone that really wants to clear away the mystery.
Charles S. Opalek, PE
August 21, 2010 at 9:36 am
“Nature loves hysteresis. ”
In other words CO2 concentrations really are “catastrophic”!
Fred Haynie said above
For a different take on the ice core data read
http://www.kidswincom.net/climate.pdf
and decide which is more consistent with physics and real world observations
Fred’s link to his own work provides a completely believable version of atmospheric changes with particular reference to CO2 variations and ice cores.
I must say I agree fully with his comments and would very much like to see this presented as a thread and let others try to take it apart. Perhaps that has already happened but I missed it?
tonyb
Ferdinand, you dont want to comment on this list? ;
http://c3headlines.typepad.com/.a/6a010536b58035970c0120a5e507c9970c-pi
I can understand that.
I remember the first time I realized that someone claimed they could measure CO2 levels back hundreds of thousands of years. I was very impressed by this scientific achievement.
Especially when I know how few people that manage to measure anything at all, without fooling themselves. Especially nowadays.
And especially if these people have some degree on some university. In that case you can be almost 100% sure they cannot even measure a voltage using a multimetre. And absolutely NOT use an oscilloscope. Or a spectral analyser.
I was also shocked once when a fresh guy came from a university in Glasgow, and could’nt solder two wires together. He said he had an MSc degree, but he certainly could not Master a multimetre or a soldering iron. I dont think he could make his own food.
Well, well, I guess these CO2 students are much better at the art of measuring. I am sure I could never measure CO2 from that far back, and claim that I knew 100% what I was doing, and be so sure it was okay…….
I would like to see some speculation on co2 causing arming from the 800000 year records, see the graphs above.
It should be possible to deduce cause-effect from the peaks on the graph.
Really, it should be a no-brainer for an able statistician to sort out if it is the warming that causes rise in co2 or vice versa?
The records have lots of peaks and stuff that ought to be possible to correlate, and those that dont should indicate who is pushing who, and how much.
Is there not even any good hypothesis on the nature of casuality?
Jeff M says:
August 21, 2010 at 11:11 am
A few people have commented on plants shutting down at low CO2 levels. Are there any natural, but non-biological or non-plant processes that reduce atmospheric CO2?
==========================================================
Yes, the formation of limestone is one.
He could be right, or he could be wrong.
@Deech56 says: August 21, 2010 at 5:48 am
“And Martin Brumby wrote: “OK, there is SOME evidence temperatures have risen over the last century.
There is a fair amount of evidence that the trace gas CO2 levels have risen over the last century. ”
Glad to see you agree with the consensus on some basic points. You did forget the other important point, though, that CO2 is a greenhouse gas. ;-)”
No, didn’t forget that.
YOU forgot that water vapout is a far more plentiful and powerful greenhouse gas than CO2.
And that the “greenhouse” effect of CO2 is logarithmic and is probably already saturated at current levels.
And that the only way the computer models can make CO2 & temperature “fit” is by assuming large positive feedbacks for which there is absolutely no evidence (unless you take the fact that every modeler has to assume basically the same thing to be “evidence”).
And you certainly forgot that the alarmists have trotted out literally hundreds of scaremongering “disaster” tipping point press releases to try to bolster their collapsing theory and that all of these scares have been shown to be far fetched or completely bogus.
And you definitely forgot that it is the alarmists who are insisting on the urgent need to spend trillions on “low carbon” energy “solutions” that don’t actually work in the real world.
And perhaps you haven’t even realised that “consensus” is a term that belongs in politics, not in science. And that the “war on global warming” is, in reality, a war on the poor.
winterkorn says:
August 21, 2010 at 9:07 am
‘If it is true that human CO2 production is only 4% of total production, then common sense indicates that a relatively small change in the other 96% (which must be biological, for the most part) could overwhelm any human change. For example a few percent change in CO2 production from the huge reservoirs of biologically available carbon (rotting vegetation, peat, coal, oil seeps, etc) could produce big changes in the overall flows in the Earth’s CO2 cycle.’
So, so, so true. The noise completely obliterates the signal across the entire spectrum, which is why <a href="http://wattsupwiththat.com/2010/08/20/engelbeen-on-why-he-thinks-the-co2-increase-is-man-made-part-2/#comment-462633" you do not see any broad correlation between human inputs and actual CO2 measurements. I have done the analysis. There are no discernible overlapping periodicities between human production and the measurements.
Ferdinand is convinced of correlation merely by the fact that two time series with slope and same-signed curvature are scale similar over a short time period. Like that is some incredibly unlikely thing, rather than virtually assured! He just doesn’t get functional analysis, and the necessity of observing ALL the base functions appearing in both the input and output.
‘The huge increases in CO2 during some interglacials in the past came from somewhere, as yet not known with certainty.”‘
And yet, Ferdinand summarily dismisses the idea that there can be any sources other than human generated, even though this simple statement proves that there are!
‘So long as these sorts of issues remain, the truth about effects of human production of CO2 should be considered as in some doubt.’
A very good post, winterkorn.
Mike Jonas says: August 21, 2010 at 5:15 am
quote
Stephen Wilde : “Then why the absence of any irregularities in the rising CO2 slope that correspond with irregularities in human CO2 emissions ? There should be such irregularities within a steadily increasing angle of curve but neither are present.”
A good question.
I made my point earlier rather briefly. I should elaborate a bit :[]
What I did find was that I could not get anything like a match to the CO2 increase by trying to ascribe it to warming oceans, THC volumes, etc. I was therefore unable to contradict F.E.’s conclusion, and I felt that having done the work I should admit the result.
The incredibly close correlation between temperature (T not dT) and annual change in CO2 shows incontrovertibly (to my mind) that temperature affects CO2 levels. The same applies to the long term record (CO2 lagging by a few hundred years). It is also obvious IMHO that ENSO affects CO2 levels. But all the analyses that I did led me to the conclusion that although these factors did affect CO2, they could not explain the rise in CO2 over the last several decades – that in the absence of fossil fuel emissions, CO2 levels would still have risen but not by much. It is possible of course that I missed something.
Hopefully someone will answer your question eventually. I can’t.
unquote
I’ve been thinking. The change in CO2 levels are a response to a change in equilibrium — this is why I found Ferdinand’s argument about mass balance so unconvincing. Something has disturbed the equilibrium between uptake and production. Once that is accepted then all falls into place.
Somewhere above, Ferdinand asks for another theory which explains all the facts. I’ll see what I can do.
JF
Ferdinand Engelbeen says:
August 21, 2010 at 7:28 am
e_por says:
August 20, 2010 at 11:23 pm
<>
Both the human emissions and the increase in the atmosphere are increasing slightly eponential, and the increase in the atmosphere follows the totallity of the emissions with an incredible fixed ratio:
<>>
My fear is that too many skeptics are defending the undefendable: that humans are not the cause of the rise. That is a point where the “consensus” is rock solid. That undermines their credibility on other points where the “consensus” is far from certain.
1. When there were large changes in fossil fuel usage such as the 1970’s fuel crisis – there is still a monotonic rise in the CO2 record. Therefore the human input to the rise must be very small. Are you suggesting that Nature somehow adjusts to fill in what humans do not produce?
2. Skeptics are not ‘defending’ anything – they are being skeptical about your assumptions and conclusions – that is what science does. Similarly –
3. In science the ‘consensus’ is almost always WRONG. Newtonian ideas on gravitation were the firmly held consensus view. Phlogiston Theory was the consensus view. People win Nobel prizes for breaking with the consensus view. If you want to rule by consensus then become a politician – you do not belong in science.
To my knowledge, there has never been any thorough validation of the accuracy of the methods used to measure CO2 in ice core bubbles. Instead, the studies done to address this mistakenly confuse precision with accuracy. If anyone knows of a reference that does validate accuracy of ice core CO2 measurements, then please let me know.
My guess is that crushing of ice core samples creates a thin water film (much like that created under the blade of an ice skate) that absorbs CO2.
tonyb and Fred Haynie:
“For a different take on the ice core data read
http://www.kidswincom.net/climate.pdf
and decide which is more consistent with physics and real world observations.”
I like that piece of work very much and would support it forming a thread here if the author agrees.
As far as I can tell every aspect of it would fit nicely with my New Climate Model.
Ferdinand Engelbeen : “Both the human emissions and the increase in the atmosphere are increasing slightly eponential, and the increase in the atmosphere follows the totallity of the emissions with an incredible fixed ratio:”
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_co2_acc_1900_2004.jpg
Actually, to my eye your graph shows greater correlation between temperature and CO2 than between emissions and CO2.
There is clearly a very strong relationship between temperature and CO2:
http://members.westnet.com.au/jonas1/deltaCO2vsTemp.JPG
and the spike at the 1998 El Nino shows that it is CO2 responding to temperature.
Note : The CO2 graph shows 12-month change in CO2 concentration, plotted at the mid-point of the 12-month period. It could be argued that it should be plotted at the end point of the 12-month period, in which case there would be an obvious timelag from temperature to CO2 change.
I have my own graph of emissions (EIA), temperature (UAH LT) and annual CO2 changes (Mauna Loa):
http://members.westnet.com.au/jonas1/EIACO2EmissionsAndTemperature.jpg
It is annual not monthly because the emissions data is annual.
It clearly shows that annual change in CO2 concentration relates far more strongly to temperature than to emissions.
But in spite of all this, I still can’t establish that the overall trend in CO2 concentrations is driven more than temperature than by emissions. But then, as I said before, maybe I have missed something.
Ian W says:
August 21, 2010 at 1:16 pm
1. When there were large changes in fossil fuel usage such as the 1970′s fuel crisis – there is still a monotonic rise in the CO2 record.
———————-
What large changes?
http://en.wikipedia.org/wiki/File:Global_Carbon_Emissions.svg
http://cdiac.ornl.gov/ftp/ndp030/CSV-FILES/global.1751_2007.csv
The total emissions in the 1970s fell by less than 10%. That means that the rate of growth of atmospheric CO2 will fall by less than 10% for a few years. Good luck in detecting that by eye.
At noon today the temperature on my stoep was 21 degrees C. Try as I might I have been unable to extrapolate from that what the temperature was today at Vostok. It seems to me that if we had a measure sure, certainly dated at 21st August, A.D. 800,000, telling us what the CO2 level was for Vostok at, say 1 meter above the ice, we would be unable to extrapolate from that the C02 level one meter above the land where my stoep now stands, on that same day. As my stoep is very close to a very warm sub tropical ocean, with the consequent vigorous biomass, I would be very surprised were I to find that atmospheric concentration here was not substantially higher than it was at Vostok.
Sorry, that should read, ’21st August, 800,000 B.P.’
“The ice cores are a reliable source of knowledge of ancient atmospheres, if handled with care. The resolution heavily depends of the accumulation rate, with as result that the data measured in enclosed air bubbles are smoothed, ranging from 8 years for the past 150 years to near 600 years for the past 800,000 years.”
Even if one was to stipulate to all the points you made in your post, the fact would remain that for the vast majority of the ice core records the temporal resolution of individual observations of CO2 is four to five times the length of the instrumental temperature record and much more than an order of magnitude times the the length of the Keeling record. As you pointed out, at best, each observation provides only a thoroughly homogenized long term average which can tell us nothing about whatever fluctuations, radical or minor, may have been occurring in the levels of atmospheric CO2 over the time span of the observation.
Even if every one of the multitude of objections to the ice core record should prove to be completely unfounded, which despite your efforts hasn’t happened yet, what we are left with is a dubious long term average for paleo CO2 that really tells us nothing meaningful about the present short term pertubations.
Aren’t there some, (or at least one), ice cores that indicate CO2 has been increasing since the ancient Egyptians about 4,500YA?
Correct me if I’m wrong.
DaveE.
“what we are left with is a dubious long term average for paleo CO2 that really tells us nothing meaningful about the present short term pertubations.”
Much like dendroclimatology then.
It is likely that ALL the available proxies are too coarse and/or insensitive to capture routine natural climate and CO2 variability on timescales less than 500 years.
For any proxy that fails to clearly pick up the MWP and the LIA that coarsness or insensitivity will apply for periods even longer and so such proxies may perhaps be wholly useless for guaging the extent and frequency of natural variations.
So our models and assumptions rely on compromised data that is wholly inadequate as a basis for any sort of comparison with the far more accurate modern methods of measurement.
Thus I prefer a clean slate whereby we start from first principles, create a hypothesis that appears to fit recent observations and progress by seeing how well or how badly it fits ongoing observations. If incorrect in any material particular it can be adjusted as necessary to maintain compliance with reality.
In theory that is what our models do but thet are now so replete with inadequate proxy data and flawed basic assumptions that we should scrap them all and start again using only the best recent directly observed data and adding to that with new data from the real world as time goes by.
Time for a completely fresh start. Preferably with fresh personnel.
I’d like to support Stephen Wilde and TonyB who would like to see Fred Haynie’s superb “citizens science paper” elevated to its own post here.
I like Ferdinand personally. Scientifically I’m tired of battling with this admirably indefatigable fighter. I still feel he is wrong and unwilling to look at material that disputes his well-thought-out hypothesis – much of which has appeared in the blogosphere. He’s battled with Tom Segalstad whom I trust better. He debunks Jaworowski on the strength of the classically awful blog SomeAreBoojums. For defence of Jaworowski, see this rendering of what I regard as Jaworowski’s most important paper, written just before despair at the corruption of science diluted his ability to stick to clear pure science without political comment.
I’d like to see Ferdinand take on Fred Haynie – truly a clash of titans. I think Fred’s science goes deeper, and supports Segalstad and Jaworowski. And thank goodness, Fred’s presentation is beautiful and clear.
stumpy says:
August 21, 2010 at 2:09 am
You have still failed to answer one key point, do co2 levels at Antarctica represent the global level? I doubt it very much given the temperature of the oceans there, and recent satelite data has confirmed its not “well mixed” as was assumed. Can you comment regarding this argument? Is there any evidence that co2 levels at Antartica represent the global average at all times in history? Is they dont, they you cannot use it for mass balance without knowing its relation to global levels and at various times i.e. interglacial, and ice age. I doubt this is possible with any certainty – therefore, great uncertainty still exists.
CO2 levels at Antarctica, Mauna Loa or Barrow (and many other places away from local/regional sources and sinks), spanning from near the North Pole to the South Pole are within 5 ppmv for yearly averages. The largest variation within a year is the seasonal variation, mainly in the NH. The largest difference in yearly averages is a lag between the NH stations and SH stations, which points to a (continuous growing) source in the NH and the ITCZ which hinders the exchanges of air masses between the NH and the SH, including CO2 (and dust). See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_trends.jpg
Thus any lag of such order (about 12 months) is of little interest for ice cores which average over 8 to 600 years…
I haven’t see yearly averages of the satellite data yet, most give only monthly averages which are influenced by the seasonal variation.
As far as I can see, the ice cores show reliable, but averaged levels of past atmospheric compositions.
kwik says:
August 21, 2010 at 3:13 am
A very interesting post. Thank you Ferdinand.
Ferdinand, what is your comment on this list here;
http://c3headlines.typepad.com/.a/6a010536b58035970c0120a5e507c9970c-pi
Off topic here, but the authors are looking at the residence time, that is how long a certain molecule resides in the atmosphere in average before being captured by vegetation or oceans. As about 150 GtC/year flows in and out the atmosphere from/to other reservoirs, the residence time, based on the througput of 150/800 = 18.8%, will be slightly over 5 years. This is what most of the items on the list show. That is what dilutes the atmospheric content e.g. of 14C from atomic bomb testing.
Not so for any increase of CO2 in the atmosphere (whatever the source): de decay rate is how fast an excess amount of CO2 injected into the atmosphere is getting back to the “normal” equilibrium, that is based on the difference between natural inputs and outputs, which is nowadays about 4 GtC sink capacity per year. Quite a difference with the 150 GtC throughput of the residence time.
Peter Dietze shows some 38 years half life time for the decay rate:
http://www.john-daly.com/carbon.htm
Thus in general: the residence time and the decay rate are two totally different items and have (near) nothing in common.
The IPCC shows a mix of different decay times, some of them hundreds of years and some near permanent, based on the “Bern model”, but I don’t think that that needs to be discussed here.
joshua corning says:
August 21, 2010 at 3:17 am
With the different characteristics of the ice layer…some layers being created during warm periods and other being created during colder periods it is possible to create a natural forward osmosis process with the differing layers of ice in which not only the concentration of the CO2 could be preserved but in fact the CO2 concentrations could be exaggerated. In other words the concentration of CO2 could be somewhat uniform through the ice but as time passes the differing layers allows H20 molecules to move yet keep the CO2 bubbles in the same place. Over time, like 800 years of time, the slight variations in CO2 concentrations could be exaggerated.
Interesting theory, but I don’t think that the differences are large enough between thousands of layers (a deglaciation takes some 10,000 years) to make this happen. And one would expect differences between the cycles, each 100,000 years apart, over time. And one would expect difference between ice cores with large differences in accumulation rate… The difference in CO2 levels are substantial (some 100 ppmv) between an ice age and an interglacial.
We have been discussing this issue in Climate Sceptic.yahoo group with Ferdinand, and he has taken with Haynie. We have not arrived at any conclusion. The discussion is almost over (I hope) so I wrote my last question:
“Risking to going back to the drawing board in ths discussion, I would like to point out some obvious thing. Sorry for throwing a brick at your window.
Dear Ferdinand,
You said (bold in uncertanties):
Humans add 7 GtC CO2 per year to the atmosphere,
nature removes 3.5 GtC per year from the atmosphere in different sinks.
The natural refresh rate of 150 GtC per year
replaces much if not all of the additional human
CO2 molecules by natural CO2 molecules.
As I understand (and all people here know) those figures are estimates, obtained through several long and complex procedures. If one or more of the original values used to calculate the result is not 100% accurate (and most of them are not), then due to the proverbial “butterfly effect” the result will be a succession of positive and negative feedbacks that can lead to weird results.
I also understand that that there is a lot of disagreement among experts in this matter, so my impression is that the 7GT CO2 emissions and 3.5 GT removal figures are not the real ones.
******************
I see too many trees in this matter, we are too close to them and that makes the forest difficult to see. Did I miss something in the issue?
Sorry I am late to this thread.
I would like to know the Argon/Nitrogen ratio through the core. It appears from Kellings work that the atmospheric Ar/N2 ratio is changing at the moment. This change would indicate a big change in the differential suitabilities of these gasses in the oceans.
Thanks, Mr. Engelbeen, for a thorough article and for your willingness to respond to many of the questions that have been raised. I continue to have a number of questions about the assumptions and methods involved in the conclusion that man is the cause of all (or the vast majority) of the increase in CO2 levels in recent decades. Nevertheless, this has been very informative, and your willingness to respond to questions in a calm manner and engage in discussion is very much appreciated.
Sorry, 3rd grade question, here:
Does ice at the poles where they drill these ice cores ever melt?
I ask because if we assume high levels of CO2 will cause warming and lead the ice to melt or just not form at all, would we ever see any evidence of those high levels of CO2 in the ice cores?
If this did actually happen and high CO2 melted the ice in the area where they drill these ice cores, you would see evidence in abrupt changes in CO2 levels. This is because the next layer of ice would be on top of and older layer that was melted down.
So, yeah, doesn’t seem like this would be a problem if that ice never melted.
Ferdinand,
A nice post. Wish I had half your enthusiasm and energy for arguing with non-sense. Keep up the good fight.
The graphs are stunning. They show a remarkably cyclical pattern before there could be any anthropogenic effect. How is this not a natural cycle?
Ferdinand Engelbeen says:
August 21, 2010 at 2:23 am
And please, NO discussion of Beck’s data here.
And please, NO dicussion of Engelbeen’s
data diatribedictates regarding CO2. Thank you.Steve Fitzpatrick says:
August 21, 2010 at 6:01 pm
Wish I had half your enthusiasm and energy for arguing with non-sense.
And I wish I had half Engelbeen’s enthusiasm and energy for arguing non-sense.
Quite a few years ago I did a little research of my own, using the NOAA iadv web site I printed out the CO2 v’s time graphs for the 20 longest running stations which represented a good global coverage then I noted the highest CO2 level and the month in which it occurred and the lowest CO2 level and its month.
Plotted these data on a CO2 concentration v’s latitude graph and the results were very interesting. The northern hemisphere shows a very marked concentration cycle but the entire southern hemisphere virtually none, In fact for 5 months of the year the southern hemisphere has a higher concentration than the northern hemisphere.
Then I went to the IPCC data and determined where the anthropogenic CO2 was released and 94% is in the north and 6% in the south. Then I went to the NOAA carbon tracker site and in those days they printed a monthly average surface CO2 profile for the world, sure enough it confirmed my graph and it also showed a distinct horizontal stratification so there is no significant mixing between the north and the south but when you calculate the impact of the CO2 released PER HEMISPHERE it is 1.15 GT per ppm so with about 8.5 GT of carbon released in the north and .5 in the south with no significant mixing why is the average northern concentration not considerably higher than the south if human emissions have such a large effect. In fact there is barely 1 ppm difference in the averages.
Barry Moore says:
August 21, 2010 at 8:30 pm
A good point, no mixing north an south, which can also be seen in the animations provided by AIRS
so there is no significant mixing between the north and the south but when you calculate the impact of the CO2 released PER HEMISPHERE it is 1.15 GT per ppm so with about 8.5 GT of carbon released in the north and .5 in the south with no significant mixing why is the average northern concentration not considerably higher than the south if human emissions have such a large effect. In fact there is barely 1 ppm difference in the averages.
The Lysenko effect?
Decide what the data should say and find it?
Ferdinand;
Did you do any measurements if the ice permeability with regard to O2 and CO2?
Did you do any measurements of the O2 and CO2 solubility in ice?
I´m not talking about pores or cracks, but permeability.
If you can not come up with good answers to this, your ice bubbles will be proxies and nothing else.
I find it deeply disturbing not to be able to discuss Herr Beck’s work. Is there any special reason for this?
Barry Moore says:
August 21, 2010 at 6:26 am
Since Ferdinand scored an F in mass balance calculations and his only response to my mathematical proof than the Anthropogenic component of the current atmosphere could not be greater than 18ppm, was that he could take no responsibility for the IPCC fig 7.3 which he agreed was substantially flawed and yet the values in the NASA numbers he quoted bore an eerie resemblance to the IPCC numbers.
I am pretty sure that you were not my examinator some 45 years ago, but as you don’t know the difference between the origin of an increase in mass and the origin of an increase in fraction I wonder who deserves an F.
Ferdinand appears to support the concept that “air” bubbles exist in the deep glaciers , this is total nonsense since the great pressure which exists in the glaciers will drive ALL the gasses below a certain depth into solution.
Read the literature before you write such things: below a certain depth, all air is captured in clathrates. But that is a two-way process, where during the relaxation of ice at normal pressure and less cold temperatures the air enclosures are reformed. These can be seen under an (electron) microscope.
Now if we reduce an “air “bubble to 1/10th its volume by compression the gas components will go into solution in the ratio of their solubilities, bearing in mind as more CO2 enters solution its partial pressure relative to the other gasses will decrease so the absorption rate will be offset somewhat but the ratio of the CO2 to the other gasses will fall rapidly. Thus we no longer have the mythical “100 000” year old “air” trapped in the ice.
Again read the literature: how much liquid water exists at -40 C, the average temperature of the Vostok ice core? Moreover, CO2 measurements are done under vacuum, which removes all CO2 and liquid water as vapour, the latter is trapped in a cold trap as ice at -70 C.
There are other much more reliable proxies than ice cores for determining CO2 content of the atmosphere such as leaf stomata and they disagree substantially with the ice core data.
Stomata data are proxies and have their own substantial problems, far worse than direct measurements in ice cores…
I see J.J.Drake’s paper was mentioned I strongly recommend people read it, his method for determining the age of the ice verses the CO2 taken from the ice was to compare the O18/O16 ratio of both the CO2 and the water, he found up to a 7000 year difference and produced a very sound correction curve for the ice core data which makes sense.
It seems that you can’t recognise a spurious correlation like the one which J.J. Drake connected. A “correction” only based on a good correlation? What physical mechanism do you think links CO2 levels in the gas phase with the gas age – ice age difference? See further the comment of DeWitt Payne…
Isotope fractionation in the ice is a result of seawater temperature at the origin of evaporation and at the place of condensation. Fractionation in the gas phase is mainly a matter of plant life and reflects the ratio ice sheets/vegetation area, both are temperature related, but independent of each other, as ice sheet formation lags temperature changes even more than CO2.
I notice the subject of Calthrates was glossed over. The missing CO2 is trapped in the ice crystals as a Calthrates and cannot be extracted which explains why the CO2 levels are low.
Complete sublimation of the total ice samples under vacuum decomposes all clathrates. No differences with the “cheese grating” technique found.
Archonix says:
August 21, 2010 at 3:48 am
And please, NO discussion of Beck’s data here.
Why not?
I am sure that would start a flame war, good for a record (even for WUWT) of over 1,ooo reactions… Thus one subject at a time…
Richard S Courtney says:
August 21, 2010 at 4:29 am
Perhaps the most important is that you gloss over a significant problem with the ice cores: viz.
liquid water exists on all surfaces of ice – including surfaces of ice crystals – at all temperatures down to -40deg.C.
There is liquid water at the ice crystals – air surface, but there is no liquid water in between crystals, except for dust/acid/salt inclusions. These are minor in the inland ice cores. And these ice cores are at or below -40 deg.C.
Therefore, it is not possible for the ice cores to indicate any high values of CO2 that existed millennia in the past, and it is not possible for bubbles in the gas to act as sealed canisters of the gas they enclose.
Ice cores of extremely different circumstances from coastal to far inland, show very little difference in CO2 levels for the same gas age. And as already said, if there was even the slightest migration, the 100 ppmv differences between warm and cold periods would fade away more and more over longer periods of time.
This is supported by the degree of adjustment the IPCC applied to ice core indications of atmospheric CO2 to provide them with agreement with the Mauna Loa data. The IPCC set the ‘ice age/gas age’ difference at 83 years to obtain that agreement.
This is pure nonsense from Jaworowski. The gas age was calculated for the Siple Dome ice core as 10 years older than atmosphere, which gives the 80-85 difference between gas age and ice age for that core. For Law Dome ice cores, the CO2 levels in the firn were measured top down: 7 years old at sealing depth, 30 years gas-ice age difference. One must compare gas composition of the same gas age with the atmospheric measurements, that has nothing to do with the age of the ice layer or the gas-ice age difference. Thus there was no “correction” at all by the IPCC.
However, as you say in your above article, Etheridge finds much shorter ‘ice age/gas age’ differences than 83 years.
And this causes a real problem.
There is no problem at all: the gas age – ice age difference depends of the accumulation rate, the higher the accumulation, the faster the sealing of the air in the layers, thus the shorter the gas-ice age difference (and the shorter the averaging of the gas phase).
If the IPCC adjustment of 83 years is an indication of diffusion (which seems likely) then all the ice core data has been smoothed by diffusion in similar manner to the conduct of an 83-year running mean.
Nothing to do with diffusion, which is in the top layers until sealing depth of the gas phase, as long as the pores are large enough. The number of ice years (thus the gas-ice age difference) plays no role in this.
Mauna Loa data has only been accumulated since 1958 (i.e. a total of 52 years) and, therefore, the 83-year diffusional smoothing in the ice would conceal any change in the atmospheric CO2 concentration similar to that observed at Mauna Loa.
Both for Siple Dome and Law Dome, the gas age is only 7-10 years, that gives an overlap of about 20 years with the South Pole data for the Law Dome data.
And if the 83-year diffusional smoothing has not happened then how do you explain the findings of Etheridge which you report?
Because there was no 83-year smoothing at all.
anna v says:
August 21, 2010 at 5:03 am
Most of mankind, lives and burns fuels at less than 1000 meters over land. Most of the flora is at less than 1000 meters over land.
You consider 70 stations enough , and those far away from sources?
Why then don’t we measure temperatures in 70 locations far away from heat sources, like deep ravines and caves? That would surely give us the energy content of the globe.
Anna, you are comparing apples with oranges. As the WUWT project of temperature stations showed: never measure temperatures above asphalt, near A/C outlets, etc. Even then it is a hell of a job to obtain something that is called a “global” average temperature, from largely varying diurnal and altitude dependent temperature readings.
The base for CO2 readings is quite similar and different:
Never use measurements near huge sources or sinks of CO2 in the atmosphere for “global” CO2 levels, as these show a local/regional bias, highly variable with diurnal variations in the hundreds of ppmv’s.
Even so, some 400 stations today measure CO2 fluxes over land, in forests, agriculture and volcanic vents, which are of interest to obtain a better insight of the carbon cycle. These stations are not used for “global” CO2 levels.
But away from such influences, the diurnal variation is less than the measurement accuracy, so that outliers are easely recognised. And the latitude and altitude differences are very modest, mainly caused by the seasonal changes and the NH-SH lag.
It is incredible that the assumption of going away from the sources of CO2 will give a correct measure of the CO2 volume in the atmosphere is considered so self evident.
Like measuring smoke to estimate the BTUs of a fire.
The CO2 measurements above 1,000 meter over land (from flights and mountains) and everywhere over the oceans show very similar CO2 levels averaged over a year. That is for some 95% of the atmospheric mass.
Should you support a proposal to lump all the temperature measurements over asphalt and near A/C’s together with the rest of the better situated stations?
Bill Illis says:
August 21, 2010 at 7:06 am
Just noting Ferdinand that the “8 ppmv/C” number is calculated using Antarctica’s temperature estimates which vary by twice as much as the global amount in the ice ages and in general. Antarctica has warmed 10C since the height of the ice age while the global value is assumed to be 5C.
The temperature proxy is based on the isotopic fractionation of water molecules when evaporating at the origin of the precipitation and out of the atmospheric water vapour at the place of condensation (I suppose directly to solids in this case). For the high altitude inland ice cores of Antarctica, that are about all SH oceans, while the coastal cores reflect more nearby water temperatures. As fas as I remember, the Greenland ice core shows about the same variation over the transitions. And the Law Dome ice core shows a change of 6 ppmv, where the reconstructions with the largest temperature differences (Esper, Moberg, Huang – bore holes) show about 0.8 C.
The current short term influence of temperature on CO2 fluctuations around the trend is about 4 ppmv/C.
Further literature of interest for Antarctic (and Greenland) ice cores see:
http://www.ipsl.jussieu.fr/GLACIO/hoffmann/Texts/jouzelJGR2003.pdf
So the 16 ppmv/C value is more accurate if one is using global or ocean water temperature changes.
Ocean temperatures may give the largest contribution for long-term CO2 changes in equilibrium level, but other items also have their contribution (vegetation as largest, opposite for temperature). But even with 16 ppmv/C, that can’t explain the 100+ ppmv increase we see…
Richard S Courtney says:
August 21, 2010 at 4:29 am
Sorry, I misundertood your last question:
And if the 83-year diffusional smoothing has not happened then how do you explain the findings of Etheridge which you report?
Most of the smoothing is in the deepest part of the firn where already closed and still open bubbles are both present. The time needed between first bubble closing and all bubbles closed is what defines the averaging. That depends of the accumulation rate, which depends mainly on ocean temperatures and resulting precipitation at the site of interest.
Barry Moore says:
August 21, 2010 at 8:30 pm
…. so with about 8.5 GT of carbon released in the north and .5 in the south with no significant mixing why is the average northern concentration not considerably higher than the south if human emissions have such a large effect.
anna v says:
August 21, 2010 at 9:45 pm
A good point, no mixing north an south, which can also be seen in the animations provided by AIRS
Dan says:
August 22, 2010 at 1:04 am
I´m not talking about pores or cracks, but permeability.
If you can not come up with good answers to this, your ice bubbles will be proxies and nothing else.
So we have some ice core proxies for CO2… of unknown accuracy / validity… which demonstrate CO2 levels vary over time. End of story.
Using the Vostok ice core proxy to determine CO2 levels world wide is pretty far fetched. It is like using today’s temperature reading from Vostok to determine today’s temperature readings for every place on earth.
There are some points which are overlooked in the discussion on the reliability of ice cores as proxies for CO2.
1. Ice cores are full of living bacteria. These organisms use CO2 as a carbon source.
(Please see here for literature: http://brent.xner.net/publications.htm)
I have discussed the influence of bacteria on the enclosed CO2 with Prof. Buford Price, one leading expert in this topic (http://icecube.berkeley.edu/~bprice/). According to him the metabolic activities of bacteria are small that in ice cores covering 1000 years we cannot see any influence but in ice cores like the Vostoc (450 000 years) the accumulated metabolism should have changed CO2 concentrations.
And what can we see in the Vostoc ice core? Very low CO2 concentrations in former glacials (~190 ppm) and interglacials (~280 ppm). Plants have many problems with such low concentrations (180 ppm), and an extinct of plants has to be found at those times, but we cannot found any. Furthermore the temperatures in the interglacials are mostly higher than today: +2-3 °C. The CO2 was very low (~280 ppm) compared to today.
2. Time lags of CO2
Analysis of modern data reveal a lag of 5 month to surface temperature (Kuo et al. 1990: http://www.nature.com/nature/journal/v343/n6260/abs/343709a0.html) using Mauna Loa data and 1 year behind SST (sea surface temperature) using combined Mauna Loa and my data (www.realCO2.de).
This suggests the CO2 variability is controlled by the oceans as the largest source of CO2.
Vostoc ice cores show about 800 years time lag CO2 behind temperature. That means our modern CO2 rise follows the Medieval optimum warmth.
But this is impossible. So the 800 years must be an artifact (as the 200 ppm in glacials) and shows distorting activities of bacteria.
3. Ice cores covering modern times (Siple, Law Dome)
These cores show partly very high CO2 which was ignored (Siple) and have a gas age/ice age of about 30 years (Etheridge). So they show an uncertainty of 30 years where they cannot resolve actual CO2 at that times.
Etheridge et al. (1996) determined the sealing depth at DE08 to be 72 m where the age of the ice is 40±1 years; so back from 1975 (end of Law Dome ice core) we have firm and diffusion of CO2. So they cannot resolve smaller CO2 variability.
Please look at this paper by Schneider and Steig:
http://www.pnas.org/content/105/34/12154.full.pdf+html
They reported of a significant 1940s Antarctic warmth detected in ice cores showing a large temperature peak in the 40s. But nothing to see in the CO2 ice cores records!
That’s exactly the 1940 CO2 maximum I have found in the direct measured data.
(and they follow temperature)
Stomata data show also much higher CO2 at that times: 330-360 ppm during ~1935-1950.
Kouwenberg at al.: http://www.geocraft.com/WVFossils/Reference_Docs/Kouwenberg_et_al_2005.pdf
4. Spectral analysis of CO2 time series reconstructed from modern ice cores (Siple. Law dome)
Every climate time series show spectral information which can often be returned to solar or lunar influence. (e.g.- H. Yndestad: http://ansatte.hials.no/hy/climate/defaultEng.htm)
Law dome and Siple dome show NO spectral information (Wavelet, MTM, http://www.realCO2.de). This looked much like an artifact!
My Conclusion:
Ice cores are only giving a rough resolution of atmospheric CO2 influenced by diffusion, 30 years uncertainty in modern times and artifacts in older series introduced by bacterial activities and other influences.
Ernst-Georg Beck
http://www.realCO2.de
There are some points which are overlooked in the discussion on the reliability of ice cores as proxies for CO2.
1. Ice cores are full of living bacteria. These organisms use CO2 as a carbon source.
(Please see here for literature: http://brent.xner.net/publications.htm)
I have discussed the influence of bacteria on the enclosed CO2 with Prof. Buford Price, one leading expert in this topic (http://icecube.berkeley.edu/~bprice/). According to him the metabolic activities of bacteria are small that in ice cores covering 1000 years we cannot see any influence but in ice cores like the Vostoc (450 000 years) the accumulated metabolism should have changed CO2 concentrations.
And what can we see in the Vostoc ice core? Very low CO2 concentrations in former glacials (~190 ppm) and interglacials (~280 ppm). Plants have many problems with such low concentrations (180 ppm), and an extinct of plants has to be found at those times, but we cannot found any. Furthermore the temperatures in the interglacials are mostly higher than today: +2-3 °C. The CO2 was very low (~280 ppm) compared to today.
2. Time lags of CO2
Analysis of modern data reveal a lag of 5 month to surface temperature (Kuo et al. 1990: http://www.nature.com/nature/journal/v343/n6260/abs/343709a0.html) using Mauna Loa data and 1 year behind SST (sea surface temperature) using combined Mauna Loa and my data (www.realCO2.de).
This suggests the CO2 variability is controlled by the oceans as the largest source of CO2.
Vostoc ice cores show about 800 years time lag CO2 behind temperature. That means our modern CO2 rise follows the Medieval optimum warmth.
But this is impossible. So the 800 years must be an artifact (as the 200 ppm in glacials) and shows distorting activities of bacteria.
3. Ice cores covering modern times (Siple, Law Dome)
These cores show partly very high CO2 which was ignored (Siple) and have a gas age/ice age of about 30 years (Etheridge). So they show an uncertainty of 30 years where they cannot resolve actual CO2 at that times.
Etheridge et al. (1996) determined the sealing depth at DE08 to be 72 m where the age of the ice is 40±1 years; so back from 1975 (end of Law Dome ice core) we have firm and diffusion of CO2. So they cannot resolve smaller CO2 variability.
Please look at this paper by Schneider and Steig:
http://www.pnas.org/content/105/34/12154.full.pdf+html
They reported of a significant 1940s Antarctic warmth detected in ice cores showing a large temperature peak in the 40s. But nothing to see in the CO2 ice cores records! That’s exactly the 1940 CO2 maximum I have found in the direct measured data.
Stomata data show also much higher CO2 at that times: 330-360 ppm during ~1935-1950.
Kouwenberg at al.: http://www.geocraft.com/WVFossils/Reference_Docs/Kouwenberg_et_al_2005.pdf
4. Spectral Analysis of CO2 time series reconstructed from ice cores
Every climate time series show some spectral information often returned to solar or lunar influence ( e.g.
http://ansatte.hials.no/hy/climate/defaultEng.htm) But Law dome and Siple dome show NO spectral information (Wavelet, MTM, http://www.realCO2.de). Looks like an artefact!
My Conclusion:
Ice cores are only giving a rough resolution of atmospheric CO2 influenced by diffusion, 30 years uncertainty in modern times and artifacts in older series introduced by bacterial activities and other influences.
Ernst-Georg Beck
http://www.realCO2.de
Alexander Pope (1688 – 1744) in An Essay on Criticism, 1709.
“A little learning is a dangerous thing; drink deep, or taste not the Pierian spring: there shallow draughts intoxicate the brain, and drinking largely sobers us again.”
Malaga View says:
August 22, 2010 at 6:04 am
So we have some ice core proxies for CO2… of unknown accuracy / validity… which demonstrate CO2 levels vary over time. End of story.
Using the Vostok ice core proxy to determine CO2 levels world wide is pretty far fetched. It is like using today’s temperature reading from Vostok to determine today’s temperature readings for every place on earth.
This does seem to be a trait in climate ‘science’ – after all they also claimed to know the climate of the world from the tree rings of a few trees in a small peninsula in Siberia.
Ferdinand Engelbeen says:
August 22, 2010 at 3:32 am
Should you support a proposal to lump all the temperature measurements over asphalt and near A/C’s together with the rest of the better situated stations?
In the ideal case, yes. Satellite temperature readings should read everything, asphalt included. It is the ground skin temperature that is radiating away the energy, not the atmosphere at 2 meters, which is a tiny part of the effect.
The problem that the surface station project is highlighting is not the asphalt per se, but the bad statistical sampling of the temperatures as global representative readings, and the time bias introduced by the UHI changes.
To get the energy leaving the globe one has to integrate over every radiating surface. Station measurements should be representative of the statistical representation of the type of surfaces the globe is composed of, an the surface station project has shown how badly this requirement is fulfilled. ( not to forget the Nyquist requirement about the sampling necessary when there are so many different types of surfaces).
The objective is to measure the energy radiated, not to sit watching it and saying: it is rising it is rising, it is falling it is falling.
Similarly, for CO2 the objective is to measure the amount of CO2 circulating in the atmosphere, from 0 meters to the stratosphere. To say that sitting far away from sources and sampling the air in 70 locations justifies the estimate of the tons of CO2 circulating is as ridiculous as saying that sampling the energy in 70 remote locations away from heat sources can estimate the energy radiated by the globe.
It is simple physics after all.
At least 99.9% of scientists agree with Ferdinand, including those who are skeptical of the notion that humans are responsible for most of the recent warming. I have looked at the data and agree that humans, mainly through burning fossil fuels, are responsible for the steady increase of atomospheric CO2 over the last 60 years or so since we have had good measurements. In my view, the scientific evidence is nearly as good as the evidence that the planets of our solar system orbit around the sun. This is smply a well-supported fact.
Thank you for your post. I’ve never really questioned that the recent rise in CO2 was anthropogenic in origin. I do question whether you can use CO2 from ice cores to measure paleo-levels of ambient CO2.
I’m with R Shearer: Ice-cores are an interesting concept, but if they are to be used to compare present day gas-phase CO2 levels with paleoclimatic levels, there is a considerable burden of proof still required. Compare the field of ice core air analysis for example to the sophistication (and profusion) of lab experiments that mineralogists perform to elucidate mineralisation pathways. Perhaps I am being too harsh and somewhere there is an accessible primer in ice-core methodology – if so, please post directions to it, I would be interested to read it.
But I want to see proof that these measurements are robust before I’d treat them as better than a proxy for ambient CO2. Is ice core CO2 really a direct measurement? I.e. are detected CO2 concentrations from samples at different depths directly comparable, or is some ‘adjustment’ required?
Also why are there so few ‘overlap’ points between ice core and ambient air? Surely by now we could get great temporal resolution for the overlap? This is a vital validation of air measurements from ice cores.
You said: “This is a nice indication that the CO2 levels of the ice cores indeed represent the ancient levels.”
It doesn’t really tell you about the ancient levels of CO2 – you’d need a measurement by a different technique that agreed with this one to do that. It does tell you that whatever processes affect CO2 in ice cores probably occur at all these sites.
I can’t avoid coming back to the fact that if ice core data is to be believed, in seeking to maintain a stable gas standard of CO2, one would use ice coated containers – yet in my limited experience of physical chemistry ice is a highly reactive surface and able to catalyse chemical pathways that are impossible based on simplistic application of gas-phase reaction pathways and thermodynamic considerations. I say again, more proof now that the data is being used by others in such a high stakes game.
Barry Moore and Anna v :
You might be interested in these graphs, which might indicate that changes in CO2 concentration are driven by tropical temperatures, with quite rapid mixing across the hemispheres.
http://members.westnet.com.au/jonas1/CO2NorthAndSouth.pdf
(167k)
And a vote from me for Fred Hynie’s work to be a post!
BillD says:
August 22, 2010 at 7:31 am
At least 99.9% of scientists agree with Ferdinand, including those who are skeptical of the notion that humans are responsible for most of the recent warming.
It is trite to say that science is not done by polling, trite but true.
A link to the poll you are quoting anyway is necessary, otherwise you should start your comment with “In my opinion at least 99.9%”, so one could give it the appropriate weight.
Mike Jonas :
August 22, 2010 at 8:06 am ,
Twelve month running averages hide the different breathing of the two hemispheres:
http://airs.jpl.nasa.gov/story_archive/AIRS-CO2-Movie-2002-2009/
Ferdinand Engelbeen,
I find very interesting this entry of yours in WUWT’s ongoing series of posts on the fundamentals of AGW theory. Thank you. You have obviously done a lot of work and thinking on this.
Before I comment on your current post, I would like to pause to reflect on the entries to date in WUWT’s recent series of posts.
NOTE: If you think I am off with my Single Bullet Descriptors please advise. I particularly had trouble bulleting Jeff Id’s post.
Ferdinand,
Note regarding context: In my view we are only discussing this topic here today because of an a priori concept/idea that a net significant AGW (compared to natural GW) is caused by anthropogenic (compared to natural source) CO2. I always need to keep that context in mind.
Your review of CO2 proxy by ice cores is unconnected yet to anthropogenic CO2 or AGW. Also, it doesn’t bring new info to the significant critical reviews of issues with ice core proxies. It can be expected that critical focus on CO2 proxies will only increase significantly in the future as tree ring temp proxies problems are currently being exposed and publicized. You seem to imply that your ice core discussion is relevant to anthropogenic CO2 or AGW. But, actually in your discussion you do not show that it is.
Shall I anticipate an eventual argument that current atmospheric CO2 increase is predominantly or completely anthropogenic? Imagine Person Z, using the context given in above note, who wants to show that current atmospheric CO2 increase is anthropogenic. Person Z shows his facts that in the modern industrial period we know that man has emitted CO2 into the atmosphere at rate of ~X and atmospheric CO2 concentration has increased at the rate of ~Y. He says that X is greater than Y. X he says is the cause of Y. The reason he says so is that it is obvious (see contextual note above) and any skeptic doubting that really reduces both the credibility of the blogs where it discussed and reduces credibility of other more responsible skeptics who are looked on more favorably by some third party. I would find this argument, by itself, unconvincing. It seems like polite blackmail.
Ancillary discussion possibly related to Person Z’s argument: Person Z might seem to say that X is the cause of Y no matter what the value of Y as long as Y is increasing. He might seem to say X the cause of Y even if the variability of X is much less that the naturally observed variability of Y. He might seem to say X the cause of Y even if prior to modern periods X is negligible or zero but changes in Y occur ( likely higher than current ones) and during those periods CO2 concentrations significantly lagged atmospheric temps. He might seem to say X the cause of Y while having a lack of referencing to the earth system total carbon cycle dynamics thus implying it is non-relevant to his argument. A total carbon cycle dynamic discussion would seem to be needed to analyze isotopic differences in CO2 from natural sources versus anthropogenic sources.
John
Ferdinand:
At August 22, 2010 at 1:20 am you assert:
“Again read the literature: how much liquid water exists at -40 C, the average temperature of the Vostok ice core? Moreover, CO2 measurements are done under vacuum, which removes all CO2 and liquid water as vapour, the latter is trapped in a cold trap as ice at -70 C.”
No!
That is a physical impossibility.
As I have repeatedly explained to you (including above at August 21, 2010 at 4:29 am) all ice – including ice crystals – is covered in a liquid phase at all temperatures down to -40deg.C. This surface film is what makes ice slippery. The amount of this water is of little importance but its existence throughout the ice matters greatly.
If, as you say, “the average temperature of the Vostok ice core” is “-40 C” then much of the Vostock ice is permeated by a 3-dimensional matrix of liquid water.
As in the last thread you hosted, you seem incapable of accepting demonstrable (and incontrovertible) facts that counter your assertions, so you fail to consider their implications.
For examle, you dispute the stomata data because you say they are “proxies”. But the ice cores are proxies, too.
Bubbles in ice cores are not sealed containers that keep any air they contain in a pristine state. They cannot be because
(a) all ice – including ice crystals – is covered in a liquid phase at all temperatures down to -40deg.C
and
(b) different gases dissolve preferentially in water
and
(c) dissolved gases diffuse from regions of high concentration.
All proxies have their uses but their limitations need to be acknowledged.
You refuse to recognise the limitations of the ice core data because you refuse to acknowledge that it is proxy data so you accept it at face value. And this refusal induces a fundamental flaw in your argument because you take the ice core data at face value and ignore that it cannot record past high values of atmospheric CO2 concentrations.
Richard
Fred H. Haynie says:
August 21, 2010 at 9:49 am
For a different take on the ice core data read http://www.kidswincom.net/climate.pdf and decide which is more consistent with physics and real world observations. Pay attention to what happens when you use the CO2 measurements with their relationship to estimated temperatures to predict temperatures to the present. The relationship holds up until about 4000 BC. after that you get a nice hockey stick that gives you unrealistically high temperatures in the last century. Something changes the CO2 at pressures and temperatures at these depths.
Also recommended by Tony B., Stephen Wilde and Lucy Skywalker.
For Tony and Lucy: hi, some time ago we have met!
About the work of Fred Haynie: sorry but that is completely unrealistic (I could use stronger words, but you know me…):
It starts on page 6:
This seasonal variation has been attributed to the cyclical respiration of the terrestrial biosphere. It is more likely related to the oceans as sources and sinks for both organic and inorganic carbon dioxide. Oceans cover most of the earth and are the greatest reservoir of carbon. Fluxes in and out of the sea surface are temperature change dependent, which is seasonal.
I t seems that Haynie has no knowledge of any of the current data, or hasn’t read anything in the scientific literature recently:
To begin with: if the sea surface temperature was the origin of the seasonal cycle, why is there practically no seasonal cycle in the SH and a large one in the NH, where there are less oceans and more land? Further:
Warmer ocean temperatures means less CO2 solubility in the seawater and increased CO2 in the atmosphere. So far so good, for the long term trend. Not so for the seasonal variation, where warmer summer temperatures show the lowest CO2 levels in the atmosphere and winters the highest. And the d13C changes are opposite to the CO2 level changes. The latter is a sign of vegetation uptake in summer: CO2 is consumed in summer, but preferentially 12CO2, leaving more 13CO2 in the atmosphere. A third point is that oxygen levels increase in summer, decrease in winter. Again a sign of vegetation at work.
The combination of all three points is consistent with vegetation growth, but conflicting with ocean temperatures for open water and conflicting for two of the three items (d13C changes and oxygen changes) for sea ice extent. But the assumption of the third item, that more ice blocks the uptake of CO2 is refuted by the increase of the THC flow (including sink rate) in winter.
Thus just by looking at the observations would have prevented Haynie to make such a remark.
Page 7:
The 308 year cycle is highly significant and fits the “hockey stick” shape of the long term curve better than an exponential form which has been attributed to anthropogenic emissions.
Come on, curve fitting to prove that humans are not the cause??? Where is the scientific feeling gone? Haynie based the 308 year cycle on 50 years of flask data, thus on less than 20% of the full period. No physical explanation, no reference to what might explain the cycle, no (proxy) data which show such a cycle. A peak of 100 ppmv each 308 years would be noticed in all ice cores, including even these with the worst resolution (Vostok about 600 years). And in stomata data and in sediments and in coralline sponges and…
Moreover, the emissions even do better than Haynie’s curve fitting:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/acc_co2_1900_2004.jpg
99.66% of the increase in the atmosphere explained by the anthropogenic emissions for over 100 years…
Correlation is not causation! Well, curve fitting is even worse in that way…
No further comment on Haynies work from my side. If Anthony wants a guest post by Haynie, we can have a more thorough discussion.
Ferdinand
Ferdinand:
I wrote my last post before I reached your post at August 22, 2010 at 2:38 am which did attempt to answer my post at August 21, 2010 at 4:29 am.
Please accept my sincere apology.
I am now responding to your reply.
You assert:
“There is liquid water at the ice crystals – air surface, but there is no liquid water in between crystals, except for dust/acid/salt inclusions. These are minor in the inland ice cores. And these ice cores are at or below -40 deg.C.”
Sorry, but as others have stated in their posts (e.g. Brego at August 21, 2010 at 10:47 am) it is an incontrovertible fact that a liquid phase exists between the ice crystals.
And you assert:
“Ice cores of extremely different circumstances from coastal to far inland, show very little difference in CO2 levels for the same gas age. And as already said, if there was even the slightest migration, the 100 ppmv differences between warm and cold periods would fade away more and more over longer periods of time.”
Again, this was answered by another poster. Ian W said at August 21, 2010 at 5:09 am:
As Richard S Courtney says there is diffusion of gases within the ice and the tendency would be for that diffusion to remove variance and end with a balanced concentration of CO2 in the ice layers. This has been measured and modeled.
Thus finding that other ice cores of similar age have similar concentrations is unsurprising and does not prove that the concentration of CO2 in the atmosphere when the firn formed was the concentration now found in the bubbles in the ice or that those values matched.”
And in response to my having written:
“This is supported by the degree of adjustment the IPCC applied to ice core indications of atmospheric CO2 to provide them with agreement with the Mauna Loa data. The IPCC set the ‘ice age/gas age’ difference at 83 years to obtain that agreement.”
You have replied:
“This is pure nonsense from Jaworowski. The gas age was calculated for the Siple Dome ice core as 10 years older than atmosphere, which gives the 80-85 difference between gas age and ice age for that core. For Law Dome ice cores, the CO2 levels in the firn were measured top down: 7 years old at sealing depth, 30 years gas-ice age difference. One must compare gas composition of the same gas age with the atmospheric measurements, that has nothing to do with the age of the ice layer or the gas-ice age difference. Thus there was no “correction” at all by the IPCC.”
Well, Jaworowski and I have been in contact for decades. This is why he trusted me to present his paper at the first Heartland Climate Conference when illness prevented his attendance. So, I cannot swear if it derives from him or from me, but I am willing to agree that it is his because Jaworowski was one of the first to conduct ice core studies and he devised most of the methods for them (Neftel et al. were still in school when he was travelling the world to obtain and analyse ice cores).
So, if I were to assume “nonsense” concerning ice core data the I would think it was from you and not him.
And there WAS an adjustment of 83 years to get the ice core data to fit the Mauna Loa data. This is a simple fact and your denal of it is “nonsense”. But, since you say Jaworowski presents “nonsense” I commend readers of this thread to assess it for themselves by reading
http://www.warwickhughes.com/icecore/zjmar07.pdf
I commend readers to view his Figures 2(a) and 2(b) at that link then to check the references he provides to that data. Simply, the IPCC set the ‘ice age/gas age’ difference at 83 years to obtain agreement between the ice core data and the Mauna Loa data”. Anybody who does this check can see that this is NOT – as you assert – “pure nonsense from Jaworowski” but is an undeniable fact.
The remainder of your response at August 22, 2010 at 2:38 am is entirely based on your unsupportable denial of the facts I state above and, therefore, is nonsense.
Richard
Ed Murphy says:
August 21, 2010 at 10:39 am
About one fifth of the world’s volcanoes are between 10°S and the South Pole.
http://www.volcano.si.edu/world/volcanocriteria.cfm
My CO2 Hoax Alarm is buzzing!
Volcanoes (estimated) emit about 1% of what humans emit. Even very large eruptions like the 1992 Pinatubo caused a drop (!) in CO2 levels as the drop in temperature removed more CO2 than the volcano emitted…
All,
Sorry, but I can’t speed up to respond on all comments, it is going quite fast now, after all I still have a life besides commenting… Thus sorry, if there is some delay and if I miss a few ones…
Ed Caryl says:
August 21, 2010 at 7:20 am
I have two problems with ice core data:
1. Ice crystals grow over time. Eventually, the ice crystals will grow larger than the ice core diameter. As ice crystals grow the grain boundaries sweep impurities, including bubbles, away. What does this do to the measurements? This is never mentioned.
2. I have doubts about measurements below 200 ppm. Photosynthesis begins to shut down at those levels. Wouldn’t rotting vegetation hold the CO2 level above 200 ppm?
1. Ice crystal growth is mainly when growing in water. In this case, snow crystals are directly formed from water vapor. The ice in glaciers is formed by compacting the snowflakes, first into firn, later into ice under pressure.
2. Also my opinion: average levels over land where plants grow are some 30-50 ppmv higher than “background”.
Was a little to fast in hitting the “post comment” button for my previous response:
2. Also my opinion: average levels over land where plants grow are some 30-50 ppmv higher than “background”. But background levels can sink to 180 ppmv, without starving plants, but as said by somebody: even the 180 ppmv need not be the bottom line…
Richard S Courtney says:
August 22, 2010 at 11:28 am
(c) dissolved gases diffuse from regions of high concentration.
—————–
What matters is not that gases diffuse, but how fast they diffuse.
Can you suggest any diffusion speeds sufficient to erase the high frequency variation you believe to be there, but slow enough to maintain the glacial interglacial differences, as well as step changes in CH4 and 15N?
“2. Also my opinion: average levels over land where plants grow are some 30-50 ppmv higher than “background”.”
—
Dubious. Perhaps under a forest canopy. If CO2 levels were this much higher over land, it would suggest that the land was a huge source of CO2.
In August 1986 in Africa, Lake Nyos released 1.6 million tons of carbon dioxide that suffocated 1,700 villagers as well as animals in valleys up to 25 kilometers (15.5 miles) away. Two years earlier in Lake Monoun, Cameroon, a smaller release of CO2 killed 37 people. Wikipedia states: Although Nyos is situated within an extinct volcano, magma still exists beneath it. Approximately 50 miles (80 km) directly below the lake resides a pool of magma, which lets off carbon dioxide and other gases; the gasses then travel upward through the earth.
What are all of the non-biological sources of CO2 on this earth? If magma possesses large amounts of CO2 under the earth’s mantle, its out-gassing might be more widespread and diffuse than in these occasional burps in volcanic lakes. …and how much CO2 escapes from earth into outer space?
Ferdinand,
Your comments are very telling as to who has a better understanding of the complexity of the math, chemistry, and physics associated with global climate change. Those that read my presentations http://www.kidswincom.net/climate.pdf and http://www.kidswincom.net/CO2OLR.pdf can be the judge.
Ernst Beck : “Vostoc ice cores show about 800 years time lag CO2 behind temperature […] the 800 years must be an artifact (as the 200 ppm in glacials) and shows distorting activities of bacteria.”
Thank you. I have long thought that the 800-year time lag was wrong, but had no option but to accept it since (a) it was what the data showed, and (b) no-one, as far as I could tell, disputed it. It was also the case, though, that (c) I couldn’t find anyone who could explain it.
Now I don’t blindly accept that what you say is corrrect, but at least you have knocked off (b) above.
Anna v : “Twelve month running averages hide the different breathing of the two hemispheres”
I am not using 12-month averages. I am using rolling 12-month differences (Jan to Jan, Feb to Feb, etc). The purpose is specifically to eliminate the seasonal variations from the figures.
on mixing across the hemispheres: It has been contended that AIRS shows no mixing between the hemispheres. Not having scanned AIRS for this I am in no position to comment on what AIRS shows.
But I do think that the graphs I linked to
http://members.westnet.com.au/jonas1/CO2NorthAndSouth.pdf
indicate that mixing does occur, and how:
We know that the prevailing wind in the centre of Antarctica is downwards – the katabatic wind. So the CO2 at the S Pole must be reaching it from higher in the atnosphere. My graphs suggest that CO2 at the S Pole is influenced by tropical temperatures. So the picture painted by the data, I would suggest, is that CO2 in rising air from the tropics is transported around the globe, north and south, and ends up at the S Pole and Barrow (and everywhere else).
The rising air at the tropics would take in emitted CO2 from the N Hemisphere, thus distributing it worldwide – without a facility such as AIRS being able to show any CO2 crossing from north to south.
Barry Moore I believe was arguing that CO2 must mix across the hemispheres, otherwise it would accumulate in the north. To my mind, he obviously has to be correct, and my graphs suggest how it happens.
*******************
richard telford says:
August 22, 2010 at 12:52 pm
—————–
What matters is not that gases diffuse, but how fast they diffuse.
Can you suggest any diffusion speeds sufficient to erase the high frequency variation you believe to be there, but slow enough to maintain the glacial interglacial differences, as well as step changes in CH4 and 15N?
**************************
1. CO2 can react with water to form carbonic acid. This would be expected to affect the alleged migration of CO2 in ice. It seems experiment with thin but intact slices of ice might shed some light on this. Nitrogen and methane are non-polar molecules and cannot form hydrogen bonds as CO2/carbonate can, so they might not move via the same mechanism.
2. In order to answer the question concerning the glacial-interglacial differences, one would have to have an independent means of measuring the actual CO2 concentration difference. It could have been much larger than we know. Then the effect of the mechanism to smooth the glacial-interglacial changes might have been more than adequate to remove high frequency information.
Richard S Courtney says:
August 22, 2010 at 12:15 pm
As Richard S Courtney says there is diffusion of gases within the ice and the tendency would be for that diffusion to remove variance and end with a balanced concentration of CO2 in the ice layers. This has been measured and modeled.
and
Thus finding that other ice cores of similar age have similar concentrations is unsurprising and does not prove that the concentration of CO2 in the atmosphere when the firn formed was the concentration now found in the bubbles in the ice or that those values matched.
First, if I remember well, there was a test of a Japanese research group, which found that there was some migration out of ice under the temperature and pressure circumstances of Vostok ice at depth, compared to ambient pressure. That showed an extremely low migration. In fact irrelevant, as there is hardly any pressure difference between ice at 2000 meter and 2001 meter depth. The recent migration calculation deduced from remelted layers at Siple Dome remains to be proven as reliable.
But nevertheless, if we may assume that there was even the slightest migration, that would level off the CO2 level differences between 280 and 180 ppmv from a warm interglacial and a cold glacial period. As the cold periods are about 10 times longer than the warm periods, the level differences would fade away over time until some 190 ppmv would be found over the full period.
If the migration was very slow, that would take a lot of time. But the ice cores present a lot of time too: Vostok shows 420,000 years and 4 warm periods, each some 100,000 years apart. With even the slightest migration, the oldest periods would show less and less difference in CO2 levels between warm and cold periods, but that is not the case. As an extra, one can compare the highs and lows of CO2 levels with the highs and lows of the temperature proxy in the ice layers, where the posibility of migration is far less than for CO2. If there was any migration, the ratio between temperature and CO2 would fade away for each interglacial, 100,000 years apart. Again that is not the case. Thus at least in the Vostok ice core, there is no measurable migration of CO2, and the 800,000 years Dome C core is going the same way…
Further, there are enormous differences in accumulation rate between different ice cores, from 1.2 and 0.6 meter ice equivalent in the Law Dome ice core to a few mm in Vostok. Even if the gas age is the same, the difference in thickness of the ice layers may be a hundredfold. Which makes the possibility that these would show the same degree of depletion/averaging quite remote. That is a fortiori the case for the “hockeystick” part over the past two centuries.
Further, again, there is no liquid water at the intercrystalline boundary. The reference to a Nature article from Brego at August 21, 2010 at 10:47 am reads about the inclusion of minuscule sulphuric acid drops at the triple point of ice crystals, that is at the edge where three crystals come together, not over the full length of the border between two crystals, which is necessary for any migration. Moreover, that was ice from the Peninsula, where salt and sulphur inclusions and higher temperatures are more common than far inland like Vostok.
A nice microscopic picture from the article in Nature can be found on a page of the warmist side, which attacks Jaworowski for misleading people with “water” in ice, while it is sulphuric acid and suggesting that that is a real problem, while it is not:
http://www.someareboojums.org/blog/?p=17
My apologies that I only can concur with their conclusions.
And there WAS an adjustment of 83 years to get the ice core data to fit the Mauna Loa data. This is a simple fact and your denal of it is “nonsense”. But, since you say Jaworowski presents “nonsense” I commend readers of this thread to assess it for themselves by reading
http://www.warwickhughes.com/icecore/zjmar07.pdf
While Jaworowski may have been thé specialist of ice cores in the early days, I have the impression that he hasn’t read anything about ice cores in the scientific literature since 1992.
About the “adjustment” I wrote already a comment in the introduction which you seems not have read, here I repeat:
Jaworowski accuses Neftel of “arbitrary” shifting the Siple data with 83 years to match the ice core CO2 with the Mauna Loa data. But the page from Neftel’s report ( http://www.biokurs.de/treibhaus/180CO2/neftel82-85.pdf ) contains two columns in the table: the counted ice age and the calculated gas age, the latter based on porosity measurements of the firn. Jaworoski used the age of the ice, not of the air bubbles, to base his accusation on, which is quite remarkable for a specialist in these matters.
Either Jaworowski doesn’t know that there is a difference between the age of the ice and the age of the gas inclusions, or he doesn’t believe it for whatever reason:
An ad hoc assumption, not supported by any factual evidence[3, 9], solved the problem: the average age of air was arbitrary decreed to be exactly 83 years younger than the ice in which it was trapped.
Where the references [3, 9] are to articles by… Jaworowski.
Anyway the gas age was calculated in the case of the Siple Dome (but see the explanations by the original author, Neftel, about that topic, here in the introduction), and measured in situ top down in firn of the Law Dome cores. Thus Jaworowski’s claim is complete bogus.
Some year ago I have sent my objections to him, but never received an answer. This part 2 was sent to him too, and to J.J. Drake as a matter of courtesy.
Jim says:
August 22, 2010 at 2:50 pm
1) And someone has already done it:
http://cat.inist.fr/?aModele=afficheN&cpsidt=20841572
And the effect of diffusion is equivalent to the smoothing by the firn (before bubble closure) by 70ka – much less at shallow, Holocene, depths
John Whitman says:
August 22, 2010 at 10:38 am
My Single Bullet Descriptor => An example of mass conservation law is claimed as evidence that CO2 directly warms atmosphere
Not at all, only written (some time ago already) because there was too much nonsense told about the origin of the increase of CO2 in the atmosphere. I am only interested what science tells me, not interested where science brings me…
My Single Bullet Descriptor =>Paleo-reconstruction of atmospheric CO2 by ice core proxies is reviewed as a potential support/basis for another future Engelbeen post on why current CO2 increase is anthropogenic.
In part yes.
Note regarding context: In my view we are only discussing this topic here today because of an a priori concept/idea that a net significant AGW (compared to natural GW) is caused by anthropogenic (compared to natural source) CO2. I always need to keep that context in mind.
I have not the slightest intention to write an article about the influence of CO2 on temperature, as I haven’t studied that in detail and the discussions I have read on that topic are partly over my head. But your conspiracy theory of WUWT slowly changing into a (C)AWG propaganda machine sounds interesting. Maybe some research grants for Anthony underway? /sarc off.
If you look at this Vostok chart, the dust and temperature measurements look more noisy than the CO2 ones. This would seem to indicate a smoothing mechanism for CO2. Also, it really looks like dust caused cooling which then caused an absorption of CO2 by oceans.
http://www.globalwarmingart.com/wiki/File:Vostok_Plot_png
Barry Moore says:
August 21, 2010 at 8:30 pm
with about 8.5 GT of carbon released in the north and .5 in the south with no significant mixing why is the average northern concentration not considerably higher than the south if human emissions have such a large effect. In fact there is barely 1 ppm difference in the averages.
There is a substantial lag between CO2 levels in the NH and the SH of about 6-24 months, depending of which stations are compared with lags over altitude and latitude, see:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_trends_1995_2004.jpg
There is of course some exchange between the NH and the SH, but it is slowed down by the ITCZ, with upwelling near the equator. That may mix only a part of air from each hemisphere. Higher air layers in the SH near the equator show slightly higher CO2 levels (1 ppmv) than lower air layers, due to that mixing.
Further, AIRS has an accuracy of about (+/-?) 10 ppmv, thus probably can’t see the differences in average, although the animation shows a little more weigth of the NH CO2 levels.
Question for Anna V.: what is the accuracy of the Japanese satellite?
Ferdinand:
Thank you for your detailed response at August 22, 2010 at 2:54 pm to my comments at August 22, 2010 at 12:15 pm.
Firstly, your comments concerning probable diffusion of CO2 through frozen ice are mistaken.
You refer to migration affected by physical pressure induced by the depth of the ice. But this is probably not relevant.
The bubbles in the ice enclose air. And the surfaces of the bubbles are coated with liquid water at all temperatures down to -40deg.C (which you admit is the average temperature of Vostock ice). But the liquid coating is only a few molecules thick.
Gases in air dissolve at a rate dependent on the partial pressures of the gas in the air and in the solvent (i.e. the solvent in this case is the layer of liquid on the bubbles’ surfaces). The physical pressure has little relevance to this.
But there is very little liquid on the surface of each bubble so little of the gas in a bubble can dissolve initially.
But there is a 3-dimensional matrix of the liquid phase on the surfaces of the ice crystals. The dissolved ions must migrate by diffusion through this matrix and, thus, reduce the concentration of the solution in the liquid on each bubble’s surface.
The migration by diffusion will provide a concentration gradient along the diffusion path(s) between the ice crystals. It is this gradient that powers the migration.
Initially the gradient is infinite, but it progressively reduces as diffusion occurs. Therefore, the rate of diffusion will reduce with time as the gradient diminishes.
But the migration depletes the gas in the liquid layer on the surface of each bubble. And this depletion will induce more of the gas enclosed in the bubble to dissolve in the liquid layer. But the amount of this gas that becomes additionally dissolved is determined by the partial pressure of the enclosed gas. And this partial pressure progressively reduces as the enclosed gas depletes (by being dissolved).
Eventually, a quasi-equilibrium of the gas in each bubble will be achieved. This quasi-equilibrium will result from
(a) the rate of the migration through the 3-dimensional matrix of the liquid phase on the surfaces of the ice crystals
and
(b) the initial concentration (so, partial pressure) of the gas in the bubbles.
Hence, it could be expected that
(i) bubbles which originally contained, for example, concentrations of CO2 in the range 400 to 500 ppmv would all eventually achieve a similar quasi-equilibrium
and
(ii) bubbles which originally contained, for example, concentrations of CO2 in the range 200 to 300 ppmv would all eventually achieve a similar quasi-equilibrium
but
(iii) bubbles that originally contained 400 to 500 ppmv of CO2 would eventually contain more CO2 than bubbles that originally contained 200 to 300 ppmv.
This model is consistent with known physics (while your is not) and is consistent with observations. And it explains why stomata data provide higher atmospheric CO2 indications than ice core data.
Secondly, your dismissal of the fact that Neftel made the ’83-year adjustment’ consists solely of unfounded ad homs. concerning Jaworowski and an untrue assertion that the references I said people should check are to references of Jaworowski.
THAT IS NOT TRUE.
Those references in Jaworowski’s paper at
http://www.warwickhughes.com/icecore/zjmar07.pdf
are
Friedli, H., Lotscher, H., Oeschger, H., Siegenthaler, U. and Stauffer, B., 1986. “Ice core record of the 13C/12C ratio of atmospheric CO2in the past two centuries.” Nature, Vol. 324, pp. 237-238.
And
Neftel, A., Moor, E., Oeschger, H. and Stauffer, B., 1985. “Evidence from polar ice cores for the increase in atmospheric CO2 in the past two centuries.” Nature, Vol. 315, pp. 45-47.
Richard
design aims in accuracy for IBUKI:
http://directory.eoportal.org/presentations/330/7450.html
• Observation of the CO2 and CH4 column density (CH4 column density during orbital nighttime):
Question for Anna V.: what is the accuracy of the Japanese satellite?
– at a spatial scale of 100-1000 km
– with relative accuracy of 1% for CO2 (4ppmv, 3 month average) and 2% for CH4
They aim at a factor of two improvement in estimates.
They were supposed to give validated data end of January this year, but I guess they are having a hard time to fit them into the expectations of AGW .
Nevertheless, the data that has been shown shows a spread larger than 10%.
First of all Ferdinand since I have had a professional engineers license for 50 years I would have been around 45 years ago to be your examiner. In the past 50 years I have occasion to perform many mass balance calculations considerably more complex than the carbon cycle.
Now ¼ of 860 Gigatonnes is still 215 Gigatonnes (mass) so your argument that fractions cannot form part of a mass balance calculation has no validity. To assume that the increase in atmospheric carbon over the last 60 years say 70 ppm at 2.2 GT per ppm = 154 GT (approximately) is nonsense since it totally ignores all the other sources and sinks which have caused all the variations in the last 800 000 years as per the ice core data. In addition we emit approximately 9 GT a year which should cause an increase of 4.1 ppm by your logic, in fact the increase in CO2 is only 1.7 ppm per year. So you not only get an F in Physics but also in basic math. Your numbers just do not compute.
If you wish to argue that only 40% of anthropogenic emissions are causing the increase as per the 1.7 v’s 4.1 then 40% of all the anthropogenic emissions in the last 60 years is nowhere near 154 GT. Please refer to Fig 7.3 Page 515 of IPCC AR4. Total all time anthropogenic emissions is 244 GT of which 100 GT is already sequestered in the deep ocean which leaves 144 GT 40% of which is 58 GT..
The half life of a CO2 molecule in the atmosphere is 4 years or less and if you put this factor into your mass balance calculation you will see how far wrong you are.
Barry Moore says:
August 22, 2010 at 10:15 pm
In addition we emit approximately 9 GT a year which should cause an increase of 4.1 ppm by your logic, in fact the increase in CO2 is only 1.7 ppm per year. So you not only get an F in Physics but also in basic math.
Sorry, but my math only calculated that the difference between the observed increase and the calculated increase is what nature has absorbed (thus 2.4 ppmv) or released, whatever the natural changes were. In this case, nature was a net sink for CO2, not a source, and the human emissions thus were the only source of the increase, regardless if part or all anthropogenic CO2 molecules were exchanged by natural ones within a minute. How much of the original anthro CO2 still resides in the atmosphere has not the slightest connection with the cause of the increase in total mass of the atmosphere.
That is the same as bringing your money to the bank: the turnover of money is gigantic, so your money disappears within seconds in the mass of transfers, but even then, the gain/loss in the balance at the end of the day can tell you if your money is part of the gain, all the gain (if the bank shows less gain than your contribution) or no gain at all. How many of your own original banknotes are still in the bank (electronically it is even zero) is of no interest for the balance.
If you wish to argue that only 40% of anthropogenic emissions are causing the increase as per the 1.7 v’s 4.1 then 40% of all the anthropogenic emissions in the last 60 years is nowhere near 154 GT. Please refer to Fig 7.3 Page 515 of IPCC AR4. Total all time anthropogenic emissions is 244 GT of which 100 GT is already sequestered in the deep ocean which leaves 144 GT 40% of which is 58 GT..
I always argued that the increase is 100% caused by humans, at least over the past 50 years, for the simple reason that nature was not a source, always a sink, for CO2.
244 GtC emitted, 144 GtC increase in the atmosphere, 100 GtC captured in other reservoirs. That is what one calls a mass balance.
The half life of a CO2 molecule in the atmosphere is 4 years or less and if you put this factor into your mass balance calculation you will see how far wrong you are.
The residence time of a CO2 molecule of about 5 years doesn’t change one gram of the mass balance or the decay time of an excess amount of CO2 in the atmosphere, which is about 40 years half life. If you don’t know the difference between a residence time, which is based on a throughput (150 GtC/year on 800 GtC), and a decay time, which is based on a sink rate (4 GtC per year), then your process knowledge is even rustier than mine…
richard telford:
I provide an explanation of the matter which you query (at August 22, 2010 at 12:52 pm) in my response to Ferdinand at August 22, 2010 at 4:24 pm.
However, the precise quantification that you request is not possible without much more research to determine diffusion rates and their decay with time.
The imortant point is (as I said in my response to Ferdinand at August 22, 2010 at 4:24 pm):
“This model is consistent with known physics (while yours is not) and is consistent with observations. And it explains why stomata data provide higher atmospheric CO2 indications than ice core data.”
Richard
Richard S Courtney says:
August 23, 2010 at 12:52 am
richard telford:
I provide an explanation of the matter which you query (at August 22, 2010 at 12:52 pm) in my response to Ferdinand at August 22, 2010 at 4:24 pm.
However, the precise quantification that you request is not possible without much more research to determine diffusion rates and their decay with time.
——————
Basically you mean you cannot be bothered to spend thirty seconds on google (try ice CO2 diffusion), or better still ISI, to find out what is known about the diffusion rates of CO2. Is ignorance that bliss?
Richard S Courtney says:
August 22, 2010 at 4:24 pm
You refer to migration affected by physical pressure induced by the depth of the ice. But this is probably not relevant.
The main force is the difference in CO2 levels. That is for all ice cores which go far enough back in time, the difference of CO2 levels between warm and cold periods, as I explained in my message. Pressure differences are of interest, as these may help to establish migration speed. But that showed very little migration and is of no interest for the circumstances in the Vostok ice core. Of more interest is that the Vostok ice core CO2 measurements show no measurable flattening over time, neither on itself, nor in ratio with the temperature variations. This points to an extremely low migration speed.
The bubbles in the ice enclose air. And the surfaces of the bubbles are coated with liquid water at all temperatures down to -40deg.C (which you admit is the average temperature of Vostock ice). But the liquid coating is only a few molecules thick.
But there is a 3-dimensional matrix of the liquid phase on the surfaces of the ice crystals. The dissolved ions must migrate by diffusion through this matrix and, thus, reduce the concentration of the solution in the liquid on each bubble’s surface.
Here you make again the same mistake: the liquid-like layer is only at the ice-air surface, not in between the ice crystals, as quite different forces come into play. That is clearly seen under scanning electron microscope and X-ray diffraction.
Further, even an older work shows the water layer thickness as a function of temperature:
http://www.phys.unsw.edu.au/music/people/publications/Fletcher1962.pdf
At -20 C that is about 15 Å, at -30 C about zero. The dynamic diameter of CO2 is about 3.9 Å, that are not really huge quantities of CO2 dissolved in the liquid layer. Below -30 C, as in the Vostok ice core, there is even no migration possible, if there was grain boundery water at all, except via relative large inclusions.
The migration by diffusion will provide a concentration gradient along the diffusion path(s) between the ice crystals. It is this gradient that powers the migration.
Initially the gradient is infinite, but it progressively reduces as diffusion occurs. Therefore, the rate of diffusion will reduce with time as the gradient diminishes.
Agreed, but no measurable changes observed over 4 periods of each 100,000 years longer…
Eventually, a quasi-equilibrium of the gas in each bubble will be achieved. This quasi-equilibrium will result from
(a) the rate of the migration through the 3-dimensional matrix of the liquid phase on the surfaces of the ice crystals
and
(b) the initial concentration (so, partial pressure) of the gas in the bubbles.
Here you are mixing two different mechanisms: an equilibrium between air CO2 and dissolved CO2 and the migration of dissolved CO2 from higher levels to lower levels via intercrystalline water or veins (if that/these exist). There is of course some equilibrium between air CO2 and water CO2 levels, but I don’t see any reason that the migration via water should stop, before all levels are equal everywhere (including the remaining CO2 levels in the air part). Only the speed will reduce with the concentration differences.
To show the same high/low ratio over the four Vostok cycles, high levels for the oldest period would need to be much higher at inclusion time (an 8-fold) than in the current warm period (pre-industrial), for a 100,000 years half life time of leveling. Followed by 4-fold and 2-fold CO2 levels in the next warm periods. Not very likely.
This model is consistent with known physics (while your is not) and is consistent with observations. And it explains why stomata data provide higher atmospheric CO2 indications than ice core data.
Your reasoning is theoretically possible, but very unlikely. Moreover, a leveling over time doesn’t change the height of the total average CO2 level over the full period of leveling, only changes the distribution. The higher levels in the stomata data are inconsistent with the ice core data and probably an artefact of the stomata data…
Secondly, your dismissal of the fact that Neftel made the ’83-year adjustment’ consists solely of unfounded ad homs. concerning Jaworowski and an untrue assertion that the references I said people should check are to references of Jaworowski.
THAT IS NOT TRUE.
Those references in Jaworowski’s paper at
http://www.warwickhughes.com/icecore/zjmar07.pdf
are
Friedli, H., Lotscher, H., Oeschger, H., Siegenthaler, U. and Stauffer, B., 1986. “Ice core record of the 13C/12C ratio of atmospheric CO2in the past two centuries.” Nature, Vol. 324, pp. 237-238.
And
Neftel, A., Moor, E., Oeschger, H. and Stauffer, B., 1985. “Evidence from polar ice cores for the increase in atmospheric CO2 in the past two centuries.” Nature, Vol. 315, pp. 45-47.
I have a similar reference to a paper where Jaworowski uses the same allegations about Neftel’s Siple Dome ice core results:
http://www.warwickhughes.com/icecore/
where he references his own work to show that the shift in ice core data was arbitrarely in
An ad hoc assumption, not supported by any factual evidence[3, 9],…
[3] Jaworowski, Z., T.V. Segalstad, and N. Ono, Do glaciers tell a true atmospheric CO2 story? The Science of the Total Environment, 1992. 114: p. 227-284.
[9] Jaworowski, Z., Ancient atmosphere – validity of ice records. Environ. Sci. & Pollut. Res., 1994. 1(3): p. 161-171.
Further, I noted excerpts from the Neftel reference in the introduction here. The original work can be read at Ernst Beck’s website:
http://www.biokurs.de/treibhaus/180CO2/neftel82-85.pdf
I recommend everybody to read that reference and compare that to what Jaworowski alleges.
Neftel calculated the gas age at closing depth and based his calculation on diffusion speed, which is inversely correlated to pore diameter and thus ice density. He checked his calculation by comparing the CO2 levels in ice bubbles at that depth with the curve of CO2 levels at the South Pole and concluded that the age of the gas phase at closing depth was 10 years older than the atmospheric CO2 levels. At closing depth, there are already 93 layers of ice, thus the difference in ice-gas age was about 83 years. Nothing arbitrarely in defining the ice age – gas age difference, only calculation and checking.
He further checked the calculated ice-gas age difference at two other depths by comparing them to the curve of South Pole levels and these agreed.
If Jaworowski alleges even recently that:
An ad hoc assumption, not supported by any factual evidence[3, 9], solved the problem: the average age of air was arbitrary decreed to be exactly 83 years younger than the ice in which it was trapped.
then in my opinion, Jaworowski is either completely incompetent or… (fill in your own opinion).
Ferdinand Engelbeen : “In this case, nature was a net sink for CO2, not a source, and the human emissions thus were the only source of the increase” and “I always argued that the increase is 100% caused by humans, at least over the past 50 years, for the simple reason that nature was not a source, always a sink, for CO2.”
Dead wrong. If we accept that temperatures have risen over the last 50 years, then the level of CO2 would have risen even without human emissions. Therefore less than 100% of the increase is caused by humans.
Simple.
“The averaging happens partly because at first the firn pores are large enough to let the air in the pores and in the atmosphere exchange with each other, partly because some bubbles close early, others at a lower depth (thus contain air which is different in composition, “age”, than other already closed bubbles). ”
Small pores allowing gas to migrate? This sounds like good conditions for reverse osmosis or ultra high filtration. I see no convincing data or study that shows that the gas bubbles are not interacting with their surroundings.
Richard Telford:
At August 23, 2010 at 3:26 am you say to me:
“Basically you mean you cannot be bothered to spend thirty seconds on google (try ice CO2 diffusion), or better still ISI, to find out what is known about the diffusion rates of CO2. Is ignorance that bliss?”
No!
That is not “what I mean” (as I suspect you know well).
Read what I wrote. The reduction of CO2 concentration in a bubble cannot be determined simplistically because it is determined by the mass flow through the very thin layers on the surface of ice crystals. And it is forced by the initial concentrations in the bubble and they are not known.
Determination of the matter would require a laboratory study lasting decades.
Richard
anna v says:
August 22, 2010 at 10:07 pm
design aims in accuracy for IBUKI:
http://directory.eoportal.org/presentations/330/7450.html
Thanks for the link!
It is quite normal that they find huge differences over land, as that is where the largest sources and sinks are situated, but the satellite shows rather large differences over the oceans, even between adjacent area’s. And that is strange, as that isn’t seen in ocean ships surveys:
http://www.esrl.noaa.gov/gmd/ccgg/iadv/ and have a look at the Western Pacific cruise data: not more than 3 ppmv around the trend, including the seasonal variation.
Further, about CO2 measurements:
Similarly, for CO2 the objective is to measure the amount of CO2 circulating in the atmosphere, from 0 meters to the stratosphere. To say that sitting far away from sources and sampling the air in 70 locations justifies the estimate of the tons of CO2 circulating is as ridiculous as saying that sampling the energy in 70 remote locations away from heat sources can estimate the energy radiated by the globe.
It is simple physics after all.
The amounts of CO2 circulating are of interest for defining the fine details of the carbon cycle, but have little interest for “global” CO2 levels and its evolution.
But if the Japanese satellite can give the exact total column CO2 for all parts of the globe, that will be excellent.
Meanwhile, why make it yourself difficult if you can measure something that approaches “global” CO2 levels within a few ppmv, just by averaging a few stations? What happens local/regional over land will be readily mixed in within a few days to a few weeks for the near-ground stations and within a few months in the altitude stations…
Mike Jonas says:
August 23, 2010 at 4:40 am
Dead wrong. If we accept that temperatures have risen over the last 50 years, then the level of CO2 would have risen even without human emissions. Therefore less than 100% of the increase is caused by humans.
The levels would have risen absent human emissions with less than 8 ppmv since the LIA (16 ppmv, if one looks at the ocean’s solubility of CO2 only). But because humans have emitted about double the increase, nature as a whole was a net sink over the past 50 years, despite the temperature increase. A net sink doesn’t contribute to an increase…
Hoppy says:
August 23, 2010 at 5:03 am
Small pores allowing gas to migrate? This sounds like good conditions for reverse osmosis or ultra high filtration. I see no convincing data or study that shows that the gas bubbles are not interacting with their surroundings.
I was waiting for this reaction, as I was wondering too. But for reverse osmosis and ultra high filtration, one needs a substantial pressure difference, which is not present in adjacent layers. The study of Etheridge ( http://www.agu.org/pubs/crossref/1996/95JD03410.shtml unfortunately behind a paywall) did what you asked: looking at the composition of several players top down in firn and in ice over the transition zone. Besides some gravitational fractionation of the different isotopes (for which is corrected), there are no problems found and the gas composition at closing depth is about 10 years older in composition (for CO2 levels) than in the atmosphere. Gas composition in already closed bubbles and still open pores was the same. Except for some fractionation of the smallest molecules/atoms as recent investigations showed (not of CO2).
richard telford says:
August 22, 2010 at 12:56 pm
“2. Also my opinion: average levels over land where plants grow are some 30-50 ppmv higher than “background”.”
–
Dubious. Perhaps under a forest canopy. If CO2 levels were this much higher over land, it would suggest that the land was a huge source of CO2.
OK, a little more complicated than could be told in one sentence…
At night, under an inversion layer (as is often the case with low wind speed), levels get skyhigh (even hundreds of ppmv over background) for the first several hundred meters of air (depends of the height of the inversion layer). That is caused by plant respiration and soil bacteria. At first sunlight, plants start absorbing CO2 and levels start falling. This goes on until currently some 50 ppmv below background levels.
But as the sun is shining and/or temperature increases and/or wind comes up, the inversion layer breaks away and the lower air layers are better mixed with “background” air, which makes that the minimum CO2 level doesn’t drop further. That makes that the average CO2 level over land in general is higher than background, and that plants at least at the beginning of the day can profit from higher CO2 levels.
In how far that is comparable with times of 180 ppmv CO2 remains an open question, I suppose that the plants slow down with their CO2 intake when the levels drop too far, but still may have some periods during the morning where they have sufficient CO2 available.
Ferdinand Engelbeen says:
August 23, 2010 at 5:25 am
underwater vents?
Plimer has said that the CO2 output just from the vents in the island of Milos in Greece represent 2% of the world (volcanic ?)output, or something like that. I am curious to see if Milos shows up, once a final map is given, that can be magnified. There seems to be a red spot in the vicinity of Greece, but the resolution is poor.
http://www.mannkal.org/downloads/environment/profpilmer.pdf
Considering that the number of underwater vents is not known, I have heard numbers like 200 000, a scenario where the chaotic motions of the magma are increasingly venting CO2, coinciding with the exit from the little ice age, cannot be dismissed without further study, for example.
Ferdinand:
In your reply to me at August 23, 2010 at 3:53 am you assert:
“The main force is the difference in CO2 levels. That is for all ice cores which go far enough back in time, the difference of CO2 levels between warm and cold periods, as I explained in my message. Pressure differences are of interest, as these may help to establish migration speed. But that showed very little migration and is of no interest for the circumstances in the Vostok ice core. Of more interest is that the Vostok ice core CO2 measurements show no measurable flattening over time, neither on itself, nor in ratio with the temperature variations. This points to an extremely low migration speed.”
No! It does not. Please read what I wrote and dispute it if you want to. But merely ignoring it and making an unfounded assertion instead does nothing for your credibility (and it is an annoying habit of yours).
Then you follow that with:
“Here you make again the same mistake: the liquid-like layer is only at the ice-air surface, not in between the ice crystals, as quite different forces come into play. That is clearly seen under scanning electron microscope and X-ray diffraction.”
You are plain wrong.
Scanning electron microscopy (SEM) cannot do it because it lacks the needed resolution.
Transmission electron microscopy (TEM) cannot do it because the transmission samples need to be too thin for the analysis.
Scanning transmission electron microscopy (STEM) cannot do it for the same reason as TEM.
X-ray diffraction (XRD) is ambiguous because the diffraction comes from near the surface of the solid.
But atomic force microscopy (ATF) suggests the effect exists between ice crystals.
And nuclear magnetic resonance (NMR) indicates that the liquid effect exists on the surfaces of ice crystals in the bulk:
e.g. ref.
VI Kvlividze et al. Surf.Sci. 44 60 (1974)
And
Y Mizuno et al. J. Phys. (France) Colloque C1 48 511 (1987)
And you assert:
“Agreed, but no measurable changes observed over 4 periods of each 100,000 years longer…”
True, but since the starting conditions are not known it is a physical impossibility to measure any changes from them.
Then you completely fail to understand what I wrote when you say to me:
“Here you are mixing two different mechanisms: an equilibrium between air CO2 and dissolved CO2 and the migration of dissolved CO2 from higher levels to lower levels via intercrystalline water or veins (if that/these exist).”
No! The two effects interact (they do not “mix”) to provide the eventual – and resulting – quasi-equilibrium. Please read what I wrote.
And you say to me:
“Your reasoning is theoretically possible, but very unlikely.”
“Very unlikely”? Prove it!
I say the mechanisms are certain to occur but the magnitude of their effect is not known but could – probably would – provide the resulting alteration to CO2 entrained in the bubbles that I describe.
Then you add more unfounded insults to Jaworowski (because you do not like what he says but cannot dispute it?) as though that affected the validity of his work one jot.
Importantly, I advised people to read references to papers by Friedli et al. and Neftel et al. that Jaworowski cited but you asserted were by Jaworowski. Now you say what amounts to “Jaworowski cites himself elsewhere”, but so what?
And if people do read the paper by Neftel et al. then they will be able to check the data and see Jaworowski’s claim is correct (whatever interpretation anybody wants to put on his text).
Richard
Richard S Courtney says:
August 23, 2010 at 5:21 am
Determination of the matter would require a laboratory study lasting decades.
————-
Is is a coincidence that this is exactly what your coal mining friends would wish for? Decades of uncertainty while some hypothetical problem is solved to your satisfaction. Fortunately, you have already answered the problem: if the diffusion rate takes decades to measure, it must be small enough to be ignored.
Ferdinand Engelbeen : “because humans have emitted about double the increase, nature as a whole was a net sink over the past 50 years, despite the temperature increase”
True.
Ferdinand Engelbeen : “A net sink doesn’t contribute to an increase”
Well that’s missing the point. You are addressing the “with-human-emissions” situation. We’re talking about what nature would have done if there had not been the human emissions. The answer is very simple – the oceans would have been net emitters of CO2. We can argue about whether the amount they would have emitted is significant, but the very simple mathematical fact is that the amount of the observed increase due to human emissions is less than 100%.
OK, let’s do some sums.
You say that “The levels would have risen absent human emissions with less than 8 ppmv since the LIA“. You mention the possibility of 16ppm, but let’s use 8ppm. In that period, the temperature rose about 1 deg C. [http://www.physicalgeography.net/fundamentals/7x.html “During the Little Ice Age, the average annual temperature of the Northern Hemisphere was about 1.0 degree Celsius lower than today.“]. Maybe the global temperature went up by less, because there is more ocean in the S hemisphere, but let’s use 1 deg C as the global increase.
Temperature in the last 50 years has risen about 0.55 deg C [http://data.giss.nasa.gov/gistemp/graphs/]. If the relationship is linear (I doubt it is, but it is probably the best available assumption) then without human emissions, CO2 levels would have gone up (8 * 0.55 / 1) = 4.4ppm.
CO2 concentrations (Mauna Loa) have gone up from 319ppm in 1960 to 390ppm now [http://www.co2now.org/]. That’s an increase of 71ppm in the last 50 years.
4.4ppm is 6% of 71ppm.
So the increase due to human emissions is 94%, not 100%.
And there are enough unknowns that I doubt anyone can guarantee that the figure is not even less.
Ernst Beck says:
August 22, 2010 at 6:04 am
So glad you could make it to the party… thank you.
Ferdinand Engelbeen says:
August 23, 2010 at 5:33 am
But because humans have emitted about double the increase, nature as a whole was a net sink over the past 50 years, despite the temperature increase.
I guess this claim is based upon your claims in your Part One paper… and Part One would be supported by your Part Two paper… sounds like a circular argument to me… suppose it just goes to prove that blinkered animals have a tendancy to walk around in circles…
Ferdinand Engelbeen,
You look busy with responding to many commenters. Thank you for taking the time for your response to my comment.
Sincerely, I was not implying, by my context statement, that you would/could/should write an article on CO2 influence on temperature. It was not my intent to imply that. I do not think I did.
Regarding what you call “[my] conspiracy theory of WUWT slowly changing into a (C)AGW propaganda machine”, my context statement was to give my view of why we are discussing CO2 in this post. My context statement is not an endorsement of the context, only stating that the context exists. It certainly did not and is not intended to be the view of WUWT/Anthony.
I do not understand how the C-word (conspiracy) came up.
John
Ferdinand,
Certainly reverse osmosis requires high pressure differential to achieve any kind of productive rate. But I believe it will still proceed even at zero delta P (random molecular motion) and would have some affect if given enough time. Say 8 years.
Richard Telford:
You assert:
“if the diffusion rate takes decades to measure, it must be small enough to be ignored.”
No, (sigh) not over millennia.
Richard
Moderator,
My recent (within last 1 hour) comment to Ferdinand Engelbeen may have gone to the nether regions of spam, etc. Can you check?
John
REPLY: fixed, Anthony
Well The very first thing that I noticed in Ferdinand Engelbeen’s graphs of CO2 and temperature is that they are plotted on different “pages”. That’s very odd for plotting scientific data, where the idea is to expose important features of the information. It a text book they would put the two graphs on difefrnet pages so you can’t really compare them.
Notice how quite by accident, the vertical size of the excursions on the two graphs are about equal; and the time scales look reasonably similar too.
So the only reason you would NOT draw moth plots on exactly the same piece of paper, is if you wanted to deliberately hide the only useful information that is on these graphs which is the time relationship beytween these two variables.
But just as Al Gor failed to hide the truth in his book; so do has ferdinand failed to hide the fact that the Temperature changes precede the CO2 changes.
One other little problem is that Ferdiand’s CO2 graph says the popresent CO2 level is 285 ppm whereas other world locations say it is about 390.
Also just looking at the two graphs one would conclude that the two variables are linearly related; there’s no evidence that they are logarithmically related; as the late Dr Stephen Schneider claimed in promulgating his “Climate Sensitivity” theory that the temperature changes proportionately with the logarithm of the CO2.
Ferdinand says that the theory relies on the assumption of a well mixed atmosphere so that CO2 is the same everywhere.
Well NOAA publishes pole to pole three dimensional graphs of CO2 in the atmosphere which show that the CO2 isn’t even approximately well mixed in the atmosphere.
At the north pole and throughour almost the entire Arctic, the annual cyclic change in CO2 has a peak to peak amplitude of 18 ppm (out of 390) which is a huge variation in such a short time, but at the south pole it is only about 1 ppm, and it goes the opposite way from the north pole. So Vostok ice core cO2 can hardly be considered representative of global CO2 since the well mixed assumption isn’t valid.
Engelbeen implies that it takes about 40 years of compaction of the snow to get good samples of the entombed atmosphere, so why does the latest data say the CO2 is 280 ppm when it hasn’t had that measured value in actual atmospheric measurements since virtually th4e dawn of “climate science.”
Just looking at the slow CO2 decay compared to the Temperature fall that causes the CO2 decline, confirms that the Temperature must be the driving signal; not the other way round.
And let’s not forget that when you have a slow sampling process such as Englebeen describes (40 years or more to collect a sample of the atmosphere), the fact that the sample time is not instantaneous, means that the frequency response of the measuring system is degraded.
As an old hand at designing sampling oscilloscope circuitry back when they first appeared in the early 1960s, I know that the frequency response of a sampled data system depends on the width of the sampling pulse or more specifically on how long it takes to shut off the sampling gate.
The result of limiting the frequency response of a sampled data system with a slwo samplign gate is that the fastest shortest lived peak values are integrated out.
So the fact that ice cores don’t seem to show CO2 levels ever going above 280 ppm, is just a natural consequence of the slow shutoff of the ice sampling gate. The transient response of the system simply isn’t fast enough to capture the real tops of the upward spikes in the CO2 signal; so if there had been peak values as high as 390 ppm; that would never be recorded by the ice core sampling system.
All of which says nothing about whether humans caused the current levels (maybe they did) but who cares, since clearly the ice core peak values clearly aren’t accurate, and CO2 isn’t the Temperature driving force anyway; even though Ferdinand Englebeen tried to hide that from us.
Richard S Courtney says:
August 23, 2010 at 8:36 am
Richard Telford:
You assert:
“if the diffusion rate takes decades to measure, it must be small enough to be ignored.”
No, (sigh) not over millennia.
————————
You don’t have millennia to diffuse away late Holocene variability of the type that Beck imagines.
*****************
Richard S Courtney says:
August 23, 2010 at 5:21 am
Determination of the matter would require a laboratory study lasting decades.
Richard
**********
But you might be able to measure the migration of CO2 through a thin slice of ice in months or less.
“One common assumption in interpreting ice-core CO2 records is that diffusion in the ice does not affect the concentration profile. However, this assumption remains untested because the extremely small CO2 diffusion coefficient in ice has not been accurately determined in the laboratory. In this study we take advantage of high levels of CO2 associated with refrozen layers in an ice core from Siple Dome, Antarctica, to study CO2 diffusion rates. We use noble gases (Xe/Ar and Kr/Ar), electrical conductivity and Ca2+ ion concentrations to show that substantial CO2 diffusion may occur in ice on timescales of thousands of years. We estimate the permeation coefficient for CO2 in ice is ∼4 x 10-21 mol m-1 s-1 Pa-1 at -23°C in the top 287m (corresponding to 2.74 kyr). Smoothing of the CO2 record by diffusion at this depth/age is one or two orders of magnitude smaller than the smoothing in the firn. However, simulations for depths of ∼930-950 m (∼60-70 kyr) indicate that smoothing of the CO2 record by diffusion in deep ice is comparable to smoothing in the firn. Other types of diffusion (e.g. via liquid in ice grain boundaries or veins) may also be important but their influence has not been quantified.”
http://cat.inist.fr/?aModele=afficheN&cpsidt=20841572
Richard Telford:
Your post at August 23, 2010 at 10:11 am is disingenuous or ill-advised.
In response to my comment concerning diffusion processes in ice that is cored to obtain samples that indicate atmospheric CO2 concentrations over hundreds of thousands of years you asserted:
“if the diffusion rate takes decades to measure, it must be small enough to be ignored.”
And at August 23, 2010 at 8:36 am I replied to that by saying:
“No, (sigh) not over millennia.”
Your post at August 23, 2010 at 10:11 am responds to that saying;
“You don’t have millennia to diffuse away late Holocene variability of the type that Beck imagines.”
Please explain what relevance – if any – that has to anything I have written.
Richard
Jim:
Thankyou for your useful comments at August 23, 2010 at 10:19 am and at August 23, 2010 at 10:26 am.
Your first says;
“But you might be able to measure the migration of CO2 through a thin slice of ice in months or less.”
I agree that you might, but I doubt it. Indeed, it is surprising that this has not been quantified if it is so simple to measure it.
This lack of quantification is confirmed by the quotation you provide (with a link to its source) in your second post. It includes this statement:
” Other types of diffusion (e.g. via liquid in ice grain boundaries or veins) may also be important but their influence has not been quantified.”
Also, that quotation agrees the existence of “liquid in ice grain boundaries” that Ferdinand denies.
Richard
George E. Smith says:
August 23, 2010 at 9:49 am
At the north pole and throughour almost the entire Arctic, the annual cyclic change in CO2 has a peak to peak amplitude of 18 ppm (out of 390) which is a huge variation in such a short time, but at the south pole it is only about 1 ppm, and it goes the opposite way from the north pole. So Vostok ice core cO2 can hardly be considered representative of global CO2 since the well mixed assumption isn’t valid.
—————–
So Vostok cannot capture seasonal variability in atmospheric CO2 concentrations because the atmosphere is not well mixed on these time tables. Big deal. Did anybody ever claim that it could? CO2 is well mixed on the relevant timescales. Compare the CO2 concentration curves from South Pole and Mauna Loa.
***********
Richard S Courtney says:
August 23, 2010 at 11:13 am
This lack of quantification is confirmed by the quotation you provide (with a link to its source) in your second post. It includes this statement:
” Other types of diffusion (e.g. via liquid in ice grain boundaries or veins) may also be important but their influence has not been quantified.”
*************
But they apparently did have reason to conclude that there is migration of CO2. From the quote: “We estimate the permeation coefficient for CO2 in ice is ∼4 x 10-21 mol m-1 s-1 Pa-1 at -23°C in the top 287m (corresponding to 2.74 kyr). Smoothing of the CO2 record by diffusion at this depth/age is one or two orders of magnitude smaller than the smoothing in the firn. However, simulations for depths of ∼930-950 m (∼60-70 kyr) indicate that smoothing of the CO2 record by diffusion in deep ice is comparable to smoothing in the firn. “
Molecular diffusion in, and flow of ice under pressure is not trivial even within a century. Check out my analysis of the high resolution Greenland isotope depletion data at http://www.kidswincom.net/climate.pdf. It is hard for me to believe that air bubbles exist under the pressure of 3000m of highly compressed ice. The bubbles most likely form during the decompression of “climatization”. Also, during that time, present day air can diffuse into the microcracks that form as the bubbles form and the ice expands. The measured air age is then an average of a mixture which varies with depth. The finding of C14 at depths older than its detectable limits strongly suggests that this has occurred.
Richard Courtney
It is unclear what magnitude and frequency of variation you believe there should have been in atmospheric CO2 concentrations. Instead you spread (or rather diffuse) doubt and uncertainty, this time about the potential for diffusion to corrupt the CO2 record in ice cores. This stratagem makes it difficult to demonstrate inconsistencies in your beliefs.
Some possible belief you might wish to adopt:
1) The glacial-interglacial difference in CO2 concentration recorded at Vostok etc is smaller than it should be because diffusion has blurred the peaks and troughs. The problem is that this would imply that glacial values were even lower than 180ppm.
2) The Holocene should have large high-frequency variations in CO2, as purported by Beck. If these are century scale then the Law Dome should detect them, unless the diffusion rate is massive, in which case the older glacial-interglacial curves would also be affected (sub-180ppm – poor plants). If the variation is decadal in scale, then the ice cores would have difficulty in recording it, but it is also difficult to think of a plausible physical mechanism that would produce large changes in CO2 concentration on a short timescales. Except of course for burning fossil fuel.
I hope your coal mining friends appreciate your efforts on their behalf.
Fred H. Haynie says:
August 23, 2010 at 1:05 pm
The finding of C14 at depths older than its detectable limits strongly suggests that this has occurred.
———-
Reference please. Or retract.
Richard S Courtney says:
August 23, 2010 at 6:14 am
No! It does not. Please read what I wrote and dispute it if you want to. But merely ignoring it and making an unfounded assertion instead does nothing for your credibility (and it is an annoying habit of yours).
I have responded to it, but you simply left it out (an annoying habit of yours):
Every time there was a warm period, one sees higher CO2 levels in the record than over cold periods. That may be caused by retained levels without much migration or by (much) higher levels in the past with migration. All warm periods in the Vostok ice core show about the same CO2 levels, as do the cold periods. And the ratio between the warm/cold periods remains about the same with the ratio of temperature between warm/cold periods.
As we have 4 (nowadays 8) periods, each 100,000 years apart, in the first case, we have no problems. In the second case, each migration period towards the past needs a doubling of the extra amount of CO2 to fulfill the decay rate which is supposed to show the current difference between the warm and cold periods (and the same ratio compared to the temperature proxy). Thus 8 times the migrating quantity for period 4 over the previous warm period in the Vostok core. Then we have period 5-8 in the Dome C record which are substantially lower than period 1-4, but even then, nothing points to a systematic reduction in level. That means that period 8 needs 8 times the migrating quantity to fulfill the migration speed of period 6. And that all without filling the cold periods too much (as these should pick up the migrating CO2).
As I said, very unlikely.
———————–
“Here you make again the same mistake: the liquid-like layer is only at the ice-air surface, not in between the ice crystals, as quite different forces come into play. That is clearly seen under scanning electron microscope and X-ray diffraction.”
You are plain wrong.
Scanning electron microscopy (SEM) cannot do it because it lacks the needed resolution.
Transmission electron microscopy (TEM) cannot do it because the transmission samples need to be too thin for the analysis.
Scanning transmission electron microscopy (STEM) cannot do it for the same reason as TEM.
X-ray diffraction (XRD) is ambiguous because the diffraction comes from near the surface of the solid.
But atomic force microscopy (ATF) suggests the effect exists between ice crystals.
And nuclear magnetic resonance (NMR) indicates that the liquid effect exists on the surfaces of ice crystals in the bulk:
e.g. ref.
VI Kvlividze et al. Surf.Sci. 44 60 (1974)
And
Y Mizuno et al. J. Phys. (France) Colloque C1 48 511 (1987)
Very impressive and I believe you for the methods used…
But by looking for the last reference, I found an old one back, where I lost the reference of (very readable, about the behaviour of the ice surface):
http://people.virginia.edu/~lz2n/mse305/ice-skating-PhysicsToday05.pdf
Indeed different methods which show the thickness of the liquid layer on the ice-air surface, but nothing about water like structures in between the crystals. Moreover, no liquid layers below 30-35 C (thus no liquid layers at Vostok, except for impurities).
The abstract of the last reference too only looks at the quasi liquid (at air) surface of ice, nothing about intercrystalline water.
And the abstract of the first reference makes it quite clear:
The NMR spectra of finely dispersed ice were investigated. It is shown that the narrow NMR signal from the ice is caused by the mobile water molecules on the ice-gas and ice-teflon interfaces.
Thus where is all that water in between the ice crystals gone?
—————
Then you completely fail to understand what I wrote when you say to me:
“Here you are mixing two different mechanisms: an equilibrium between air CO2 and dissolved CO2 and the migration of dissolved CO2 from higher levels to lower levels via intercrystalline water or veins (if that/these exist).”
Maybe I have expressed myself not that clear, but I suppose that you see that I have understood what you wrote, as you need increasing CO2 levels as start condition further back in time to end with the current rather similar CO2 levels over warm vs. cold periods, if there was substantial migration. See the item at the beginning.
——————-
Then you add more unfounded insults to Jaworowski (because you do not like what he says but cannot dispute it?) as though that affected the validity of his work one jot.
And if people do read the paper by Neftel et al. then they will be able to check the data and see Jaworowski’s claim is correct (whatever interpretation anybody wants to put on his text).
If you really think that Jaworowski is correct by accusing Neftel of “arbitrarily” shifting the data with 83 years then there is no hope left. He writes literally
An ad hoc assumption, not supported by any factual evidence, while it is clear from about all available scientific literature and simple logic, that there is a difference between the age of ice and the age of the enclosed air, for the simple reason that firn is an open system until the permeability is low enough to prevent further exchanges with the air above it.
One can discuss that it was 70 years or 90 years difference between the ice age and the gas age for the Siple Dome ice core, but as Neftel did compare his measurements at closing depth with the South Pole measurements and for two other depths, there is little doubt that he was right and Jaworowski just is talking nonsense, “not supported by any factual evidence”.
Richard Telford:
Your message to me at August 23, 2010 at 1:47 pm begins by saying:
“It is unclear what magnitude and frequency of variation you believe there should have been in atmospheric CO2 concentrations. Instead you spread (or rather diffuse) doubt and uncertainty, this time about the potential for diffusion to corrupt the CO2 record in ice cores. This stratagem makes it difficult to demonstrate inconsistencies in your beliefs.”
That is offensive and untrue so I have not bothered to read any more of your post.
1.
If anything I wrote is unclear to you then state it and ask for a clarification.
2.
I do not “believe” anything about this subject. On the contrary, if you had read my posts here then you would know that I think the ice core data is incapable of providing definitive knowledge of past atmospheric CO2 concentrations.
3.
I do not know what variations should be in past atmospheric concentrations but I suspect (n.b. NOT “believe”) they should be similar to the indications of stomata data.
4.
I do not “spread (or rather diffuse) doubt and uncertainty” but I do promote and practice proper scientific scepticism (which your posts lack).
5.
The “potential for diffusion to corrupt the CO2 record in ice cores” is a scientific fact (read the posts and link provided by Jim at August 23, 2010 at 10:26 am and August 23, 2010 at 12:30 pm).
6.
I have no “stratagem”.
7.
There are no “inconsistencies in [my] beliefs” and my beliefs are not relevant to any discussion on this thread.
If you post a reasonable comment to me then I will read it, but I have only read the first paragraph of your post at August 23, 2010 at 1:47 pm and I have no intention of reading any more of it. As my response shows, that pargaraph is offensive, insulting and untrue drivel. No sensible person would bother to read any more of such stuff.
Richard
George E. Smith says:
August 23, 2010 at 9:49 am
Well The very first thing that I noticed in Ferdinand Engelbeen’s graphs of CO2 and temperature is that they are plotted on different “pages”. That’s very odd for plotting scientific data, where the idea is to expose important features of the information. It a text book they would put the two graphs on difefrnet pages so you can’t really compare them.
George, this was just an illustration of the comparibility of the graphs. The important one is the one below it: the rather linear ratio between CO2 and temperature. And you have obviously not read what I wrote above the CO2-temperature graph:
The visual correlation between temperature and CO2 levels in ice cores is well known to everybody, as that was used by Al Gore and many others, although he forgot to tell his audience that the CO2 levels lagged by some 800 years during a deglaciation and many thousands of years at the onset of new glaciations:
Thus before you accuse somebody, first read what he says.
Engelbeen implies that it takes about 40 years of compaction of the snow to get good samples of the entombed atmosphere, so why does the latest data say the CO2 is 280 ppm when it hasn’t had that measured value in actual atmospheric measurements since virtually th4e dawn of “climate science.”
Again you haven’t read what was said in the introduction: The Law Dome needs 40 years of compaction of the snow, but the air still is in open contact with the atmosphere and is only 7 years older than the open air at closing depth. Thus the CO2 levels digged in 1990 contains air from around 1980 and show levels of 335 ppmv, the same CO2 levels measured at the South Pole. Because the South Pole measurements started before 1960, there is an about 20 years overlap between the South Pole data and the Law Dome ice core data.
Further, indeed ice cores are averaging the CO2 data, depending of the amount of snowfall at the drilling site: more snowfall, faster compaction and less averaging of the CO2 data. The averaging is between 8 years (Law Dome) and some 600 years (Dome C). The fastest accumulating ice cores do record any peak of 20 ppmv, lasting one year or any increase of CO2 of 2 ppmv lasting some 10 years. But not farther than some 150 years back in time. The resolution becomes worse, the farther you go back.
Ferdinand:
I am replying to your post at August 23, 2010 at 3:21 pm .
You have replied to my complaining that you had not addressed my argument by your asserting:
“I have responded to it, but you simply left it out (an annoying habit of yours):”
OK. Where did you reply to the argument that I actually made?
I have read all your comments more than once and I fail to see it.
Then you repeat your assertions that completely ignore my argument (again).
You say;
“Every time there was a warm period, one sees higher CO2 levels in the record than over cold periods. That may be caused by retained levels without much migration or by (much) higher levels in the past with migration. All warm periods in the Vostok ice core show about the same CO2 levels, as do the cold periods. And the ratio between the warm/cold periods remains about the same with the ratio of temperature between warm/cold periods.”
Yes!
As I explained – and you again ignore or fail to understand – that is what one would expect to see as a result of the quasi-equilibrium I said could be expected to result from diffusion. So, it is NOT supporting evidence for your assertions.
Then you say;
“As we have 4 (nowadays 8) periods, each 100,000 years apart, in the first case, we have no problems. In the second case, each migration period towards the past needs a doubling of the extra amount of CO2 to fulfill the decay rate which is supposed to show the current difference between the warm and cold periods (and the same ratio compared to the temperature proxy). etc.”
No! It does not. I again ask you to read what I wrote. You have again ignored it completely.
Your claim that this is “very unlikely” is true of what you say concerning your imagined “doubling of the extra amount of CO2 to fulfill the decay rate” but is not – repeat, NOT – true of the probable quasi-equilibrium that I described.
We can swap references and our interpretations of them for ever, but the fact is that the liquid layer DOES exist between the ice crystals and this DOES enable diffusion. Please see the posts from Jim at at August 23, 2010 at 10:26 am and August 23, 2010 at 12:30 pm which demonstrate that leading ice core analysts agree it exists and that diffusion occurs at an unknown rate through it.
And you conclude by dismissing Jawarowski’s correct statement concerning the IPCC ice age/gas age difference with yet another ad hom. This does you no credit.
Richard
Jim says:
August 23, 2010 at 12:30 pm
***********
But they apparently did have reason to conclude that there is migration of CO2. From the quote: “We estimate the permeation coefficient for CO2 in ice is ∼4 x 10-21 mol m-1 s-1 Pa-1 at -23°C in the top 287m (corresponding to 2.74 kyr). Smoothing of the CO2 record by diffusion at this depth/age is one or two orders of magnitude smaller than the smoothing in the firn. However, simulations for depths of ∼930-950 m (∼60-70 kyr) indicate that smoothing of the CO2 record by diffusion in deep ice is comparable to smoothing in the firn. “
Thanks Jim for this quote. Thus quantitatively:
The smoothing of the CO2 data from the Siple Dome ice core was estimated (based on firn densification at closing depth) to be around 23 years.
The deepest layers (representing air of 60-70 kyr ago), then would show a spread of around 46 years, but the younger parts are hardly affected.
That means that one need to be cautious about the resolution of the “warmer” ice cores. And in this case also about the accuracy of the CO2 measurements, as the ice core also shows CO2 peaks of about 20 ppmv, probably from the presence of remelt layers.
Richard S Courtney says:
August 23, 2010 at 4:17 pm
To repeat your argument:
Eventually, a quasi-equilibrium of the gas in each bubble will be achieved. This quasi-equilibrium will result from
(a) the rate of the migration through the 3-dimensional matrix of the liquid phase on the surfaces of the ice crystals
and
(b) the initial concentration (so, partial pressure) of the gas in the bubbles.
At which I responded:
“but I don’t see any reason that the migration via water should stop, before all levels are equal everywhere (including the remaining CO2 levels in the air part). Only the speed will reduce with the concentration differences.”
Your quasi-equilibrium is a false one, as the leveling simply will go on as long as there are differences in CO2 levels, if there was any migration at all. What we see in reality is differences in CO2 levels which are about equal over 4 periods of each 100,000 years.
The only way to obtain the same CO2 levels in warm periods today if there was migration, is by increasing levels at start condition, for each period huge enough to show about the current (pre-industrial) CO2 level with the migration speed. As the migration speed depends of the concentration differences and the concentration difference reduce over time, one need a doubling of the initial quantities for each period back in time.
Richard S Courtney says:
August 23, 2010 at 4:17 pm
Forgot to add:
Other types of diffusion (e.g. via liquid in ice grain boundaries or veins) may also be important but their influence has not been quantified.”
As the whole investigation showed, this seems all about diffusion through the ice itself, although I don’t see a physical explanation how that can happen through the ice matrix. But they exclude liquid in ice grain boundaries or veins for what they have done.
There may be some, but all the references I have found only show ice-air waterlike layers, without any reference to intercrystalline water. And definitively not below -30 to -35 C, while Vostok is average -40 C.
“There is evidence that liquid water is present in pure ice down to temperatures
of around — 13°C, the approximate temperature at which the liquid-like signal
in NMR spectroscopy falls below the limit of detection (Bell et al, 1971,
Kvlividze et al, 191 A). Of course, these experiments give no indication of where
the water may be found but, following the work of Nye and Mae (1972), it
seems likely that the NMR liquid signal originates at the grain boundaries of
the ice. Nye and Frank (1973) have advanced thermodynamic arguments which
indicate that any water present as bulk liquid in equilibrium with the solid must
be found at triple junctions which form interconnecting networks in the ice. A
thin liquid-like layer may also exist at free surfaces (Fletcher, 1968) and possibly
even at grain boundaries.”
http://www.google.com/url?sa=t&source=web&cd=10&ved=0CDsQFjAJ&url=http%3A%2F%2Fiahs.info%2Fredbooks%2Fa118%2Fiahs_118_0263.pdf&rct=j&q=water%20between%20ice%20grains&ei=GyFzTLvCPIGclgehn_U_&usg=AFQjCNGfWXkRDIeRMCuqrRA7N6vYh3QFfw&cad=rja
Ferdinand I would like to preface my remarks with a sincere appreciation for your diligent responses to the blogs,” I may not agree with what you say but I will defend with my life your right to say it”
There is obviously a great extent of research papers on both sides of this debate and one can cherry pick the papers to “ prove” either argument thus the debate continues ad nausem.
However returning to the mathematics of the mass balance which is not subject to the above bias.
I think the critical oversight you make with your rusty knowledge of process calculations is that exchanges will occur with respect to quantities of natural and anthropogenic carbon in between the air, ocean and land in the ratio that exists in the sources.
Thus if the air contains 80% natural and 20% anthropogenic carbon the land and the ocean will absorb the carbon in that ratio. So in the case of 150 GT ( it is a lot more but we will use your number) the sinks absorb 30 GT of anthropogenic carbon. However they only emit the ratio of the N to A carbon that they contain i.e. for oceans 900 to 18 and for land 2300 to 101 per IPCC AR4 page 515. Thus there is a large imbalance of carbon absorption in the land and oceans verses emissions by human plus reemission from the land and ocean if we use your assertion of the anthropogenic content of the atmosphere.
Frankly your argument against this relatively simple mathematical analysis is as distorted as your responses to so many valid arguments, 40 year half life, give me a break that is pure smoke and mirrors IPCC double speak.
Once again let me quote from the IPCC 4th AR page 446 Box 6.2.
“ Ice core records show that atmospheric CO2 varied in the range 180 to 300 ppm over the glacial-interglacial cycles of the last 650 kyr … The quantitative and mechanistic explanation of these CO2 variations remains one of the major unsolved questions in climate research”
That is because it never happened. The ice core data is substantially flawed.
Jim says:
August 23, 2010 at 6:37 pm
“There is evidence that liquid water is present in pure ice down to temperatures
of around — 13°C, the approximate temperature at which the liquid-like signal
in NMR spectroscopy falls below the limit of detection (Bell et al, 1971,
Kvlividze et al, 191 A). Of course, these experiments give no indication of where
the water may be found but, following the work of Nye and Mae (1972), it
seems likely that the NMR liquid signal originates at the grain boundaries of
the ice. Nye and Frank (1973) have advanced thermodynamic arguments which
indicate that any water present as bulk liquid in equilibrium with the solid must
be found at triple junctions which form interconnecting networks in the ice. A
thin liquid-like layer may also exist at free surfaces (Fletcher, 1968) and possibly
even at grain boundaries.”
Thanks for the link! It shows that water is mainly found at the triple points, which are isolated parts in the ice. To sustain migration of CO2 via water one need water with a sufficient layer thickness at the grain boundaries to let CO2 or (bi)carbonate ions pass the ice. And that is what I haven’t found yet.
And temperature is of course important, at -13°C, the water layer at the ice-air border is much thicker than at -23°C (Siple ice core) and completely absent at Vostok (-40°C)…
The Siple core shows an extra 23 years smoothing after some 60,000 years of migration, but also problems due to remelted layers. If we assume the same migration speed at Vostok (in fact much less, due to much colder temperatures, no remelt), that would give an increase to about 650 years averaging for the CO2 levels, compared to the estimated 600 years now, after 100,000 years of migration, 700 after 200 kyr, 750 after 300 kyr and 800 after 400 kyr (I know, that is linear, while it is not, but so what). And that would be (hardly) visible as an increased smoothing for each period further back in time.
No big deal, as a transition from cold to warm needed some 5000 years and back is over 10000 years. And that doesn’t change the average, only the resolution gets worse.
Ferdinand:
This is a brief initial response to your comment at August 23, 2010 at 5:01 pm because I have to leave for a business appointment. I will provide a full answer when I return this evening.
Thankyou for your clarification that demonstrates your misunderstanding. It says:
“At which I responded:
“but I don’t see any reason that the migration via water should stop, before all levels are equal everywhere (including the remaining CO2 levels in the air part). Only the speed will reduce with the concentration differences.”
Your quasi-equilibrium is a false one, as the leveling simply will go on as long as there are differences in CO2 levels, if there was any migration at all. What we see in reality is differences in CO2 levels which are about equal over 4 periods of each 100,000 years.”
That is so removed from reality that it is no wonder I failed to recognize that you had tried to address my explanation!
It is plain wrong that “the leveling simply will go on as long as there are differences in CO2 levels”. The “leveling” will reduce to almost nothing when the partial pressure gradient at the tip of the diffusing agent becomes very small.
As an illustration, I point out that this reduction of diffusion rate is why steel can be used as reinforcement in concrete. Iron oxide is about four times larger than the oxidised iron. So, if steel rusts it breaks the concrete. (Many people have seen a concrete fence post that has been destroyed by rusting of its internal steel reinforcement that is close to the post’s surface). But if the concrete’s steel reinforcement is about 10 cm or more from the concrete surface then the steel does not rust. This is because the diffusion rate decreases to almost nothing when the partial pressure gradient at the tip of the diffusing oxygen becomes very small, and the partial pressure gradient reduces with distance from the high partial pressure at the concrete surface.
The same effect must occur with diffusion of CO2 through ice crystal boundaries.
Must rush now so will read the rest of your posting when I get back.
Richard
Barry Moore says:
August 23, 2010 at 7:34 pm
Ferdinand I would like to preface my remarks with a sincere appreciation for your diligent responses to the blogs,” I may not agree with what you say but I will defend with my life your right to say it”
Thanks!
Thus if the air contains 80% natural and 20% anthropogenic carbon the land and the ocean will absorb the carbon in that ratio. So in the case of 150 GT ( it is a lot more but we will use your number) the sinks absorb 30 GT of anthropogenic carbon.
Agreed.
However they only emit the ratio of the N to A carbon that they contain i.e. for oceans 900 to 18 and for land 2300 to 101 per IPCC AR4 page 515. Thus there is a large imbalance of carbon absorption in the land and oceans verses emissions by human plus reemission from the land and ocean if we use your assertion of the anthropogenic content of the atmosphere.
Agreed, but if you use the more realistic figures, anthropogenic CO2 (aCO2) is less than 10% of the atmosphere and supply and removal of aCO2 are more or less in balance (a slight increase, because aCO2 emissions still are increasing).
Frankly your argument against this relatively simple mathematical analysis is as distorted as your responses to so many valid arguments, 40 year half life, give me a break that is pure smoke and mirrors IPCC double speak.
The error you and many before you make, is to make a distinction between the origin of the molecules in the atmosphere and the origin of the increase in total mass of CO2 in the atmosphere.
The origin of the type of molecules in the atmosphere is governed by two items: the supply of aCO2 and the refresh rate. For the sake of clarity, let’s assume that all aCO2 has a red color.
Thus at year one: 8 GtC red CO2 enters the atmosphere and the fraction of red color increases from zero to 0.01. Total mass in the atmosphere increases from 800 to 808 GtC. Independent of the red color, a stream of 150 GtC nCO2 enters the atmosphere and 154 GtC (n + a)CO2 leaves the atmosphere. Net result: an increase of total mass from 800 to 804 GtC CO2 and an increase of 0.08 in red fraction, or 6.5 GtC red CO2 (some 20% removed by the refresh rate). I hope we may say that the increase in mass may be fully attributed to the addition of aCO2, as the other flows are a net sink, even if the fraction aCO2 is less than 1% by now.
Year two: same scenario: 8 GtC red CO2 in, 150 GtC nCO2 in (not completely right: part of aCO2 returns back from other reservoirs, but let’s have it clear), 154 GtC mix out, again removing 20% of the red CO2, total mass increases to 808 GtC, of which some 11 GtC or 0.015 fraction is red CO2. But still the full increase is caused by the 8 GtC injection, as the balance between natural inputs and natural outputs is negative.
Thus at last, for at least the past 50 years, the fraction of aCO2 increases slowly in the atmosphere until as much aCO2 is removed as is injected, to reach at maximum less than 10% nowadays. Thus the red colored aCO2 increases the redness of the atmosphere, but slowly until an equilibrium is reached.
But the full increase is attributable to the injection of aCO2, as nature was a net sink all over the years.
The refresh rate of 150 GtC doesn’t change the total mass in the atmosphere, it only governs how much red CO2 resides there, it is only the imbalance which adds or removes CO2 from the total mass in the atmosphere.
The near 40 years half life time is not from the IPCC (which uses a set of much shorter and much longer decay times) but from a known (C)AGW skeptic: Peter Dietze, see: http://www.john-daly.com/carbon.htm
Ferdinand:
I am back and have now read all your post at August 23, 2010 at 5:01 pm and the subsequent posts.
Jim seems to have covered all that matters in his contributions (I do not know who ‘Jim’ is but I brook that he knows more about ice core analysis than yourself).
I only now write
(a) to show I am not ignoring your points
and
(b) to make sure that I completely refute one of your mistaken assertions.
You assert in your post at August 23, 2010 at 5:01 pm :
“The only way to obtain the same CO2 levels in warm periods today if there was migration, is by increasing levels at start condition, for each period huge enough to show about the current (pre-industrial) CO2 level with the migration speed.”
No!
This is a complete misunderstanding on your part.
If diffusion through a matrix operated like that then all steel-reinforced structures would fall down in less than 10 years (please see my explanation of this in my post at August 24, 2010 at 1:45 am).
A quasi-equilibrium becomes established in the manner I explained at August 22, 2010 at 4:24 pm. And the result would be – as I there explained – exactly what we see in the ice cores.
Some here doubt your knowledge of mass balance analyses. I know your writings here demonstrate your lack of knowledge of materials science.
Richard
One thing that ice core data tells us is that the process rates upon which “climatetology” of the earth is calculated has never been “more or less in balance”. The rates of change for different processes vary within and between processes. The ice core data shows us that both internal and external forces and their interactions cause these rates to change in cycles. The problem we have with the ice core data, in trying to establish cause and effect, are the limitations with respect to accuracy and time resolution. The CO2 data is probably the most limited.
Thanks, Ferdinand, for your patience. I’m not easy to convince, but find your analysis convincing. And right up front you state that this has nothing to do with the “CO2 is causing runaway warming” mantra.
This topic really should be a formal paper, but it prb’ly wouldn’t be accepted unless you put the obligatory “we’re all doomed” or equivalent as the last sentence.
Richard S Courtney says:
August 24, 2010 at 5:59 am
OK, I have no problem to assume that the oxydation of steel in concrete shows little migration of oxygen in the deeper layers (although some 50 year old bridges needed to be renewed here, due to “concrete rot”, be it probably from adding CaCl2 for fast hardening in the past).
But let us look at the probability and the results of a similar mechanism in ice cores.
In my opinion, the ice core matrix is more closed than a concrete matrix, but nevertheless, let’s go on.
A quasi-equilibrium becomes established in the manner I explained at August 22, 2010 at 4:24 pm. And the result would be – as I there explained – exactly what we see in the ice cores.
That is what I doubt: assuming that the CO2 levels in a warm period were substantially higher than observed today, that should migrate from the higher levels to the lower, thus spread over a longer period, until the higher level is at the quasi-equilibrium.
A relative concrete example: assume that the CO2 levels in the atmosphere in the previous warm period, the Eemian, were the same as today (temperatures were somewhat higher than in this period), then migration would spread the 390 ppmv CO2 levels over a longer period, until the quasi-equilibrium of 290 ppmv is reached. Indeed there is a long tail of high CO2 levels in the Eemian, while temperature (and CH4) is falling (see
http://www.ferdinand-engelbeen.be/klimaat/eemian.html for a graph of the Eemian).
But I don’t see a reason why the migration doesn’t go back in time (or in this case: further down the ice): the CO2 levels before the rise in temperature are very low (190 ppmv) and follow temperature with some 800 years lag when temperature goes up. With a two-sided migration of an extra 100 ppmv during 10,000 years, CO2 levels should preceed the temperature rise with thousands of years. A one-way migration seems very unrealistic to me, the more that the levels before the rise in temperature are lower than after the cooling down.
Next the warming from the LGM (last glacial maximum) until the Holocene optimum (again somewhat warmer than the current warm period: North Pole largely icefree at least in summer): CO2 levels follow the temperature increase with a lag of again some 800 years, see:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/epica5.gif
with thanks to André Van den Berg who provided the graph.
Once the warm period would have been reached, the CO2 levels would increase over the quasi-equilibrium level and should spread two-way. Back: nothing to see. Forward: an small increase since about 4000 years, but rapid since about 160 years. But if the real CO2 levels in the ice indeed were 390 ppmv in the past 10,000 years, where is all that CO2 gone?
Think about this as a probability and how it would affect the CO2 ice core data. Let’s assume that under the weight of all the ice above it, the ice at depths acts as an amorphous mass like glass and flows ever so slowly under the pressure. At some point in depth and time, bubbles would no longer exist. Where do the highly compressed and cooled gases go, by what mechanism, and how fast?
Fred H. Haynie says:
August 24, 2010 at 10:25 am
Think about this as a probability and how it would affect the CO2 ice core data. Let’s assume that under the weight of all the ice above it, the ice at depths acts as an amorphous mass like glass and flows ever so slowly under the pressure. At some point in depth and time, bubbles would no longer exist. Where do the highly compressed and cooled gases go, by what mechanism, and how fast?
Under sufficient pressure, and low temperatures, all air molecules disappear as clathrates. When the ice cores are retreeved, they are stored at normal pressure at low temperatures (below -20°C) mostly under the surface on site for up to a year. This allows the ice to expand again, reforming gas bubbles from the clathrates. This is called relaxation of the ice.
Measurements are done under vacuum while crushing the ice. Eventually surviving clathrates decompose rapidely under vacuum.
Ferdinand,
With all this that you know has occured you still expect the concentrations in the reformed bubbles to be the same as when it was first trapped? How much carbon in some form is retained in the ice when the bubbles are formed and when the ice is crushed?
Mike Jonas says:
August 23, 2010 at 6:45 am
Sorry, there was too much traffic and I had only a limited time to respond in last days…
Temperature in the last 50 years has risen about 0.55 deg C [http://data.giss.nasa.gov/gistemp/graphs/]. If the relationship is linear (I doubt it is, but it is probably the best available assumption) then without human emissions, CO2 levels would have gone up (8 * 0.55 / 1) = 4.4ppm.
CO2 concentrations (Mauna Loa) have gone up from 319ppm in 1960 to 390ppm now [http://www.co2now.org/]. That’s an increase of 71ppm in the last 50 years.
4.4ppm is 6% of 71ppm.
So the increase due to human emissions is 94%, not 100%.
Well, the increase in temperature certainly added more CO2 to the total natural input flows, but it didn’t add to the increase, as the total natural outflows were larger…
In the same way, one can look at all natural inputs as contributing to the increase, like the permanent oceanic releases near the equator (also temperature controlled), which may be a factor 5 larger than the human emissions, but then forget that at the other side of the world more CO2 is removed near the poles.
Even for one-way additions like volcanic vents: there are also one-way CO2 sinks like rock weathering and carbonate deposits in the oceans by coccoliths. In all cases the inputs are more than compensated by the outputs.
One can discuss if a lower sink rate (thanks to an increase in temperature, gigantic forest fires,…) also is a form of “addition”, but that is rather academic…
But in fact this is a discussion for part 1 (but I didn’t look there for a while)…
Fred H. Haynie says:
August 24, 2010 at 12:35 pm
With all this that you know has occured you still expect the concentrations in the reformed bubbles to be the same as when it was first trapped? How much carbon in some form is retained in the ice when the bubbles are formed and when the ice is crushed?
With the crushing technique, less than 80% of the air (including CO2) is recovered, but that doesn’t change the composition, the remainder is in bubbles which didn’t crush.
But one does regularly measurements (especially for isotope compositions, to be sure that no fractionation takes place) where all ice is sublimated under vacuum and water and air cryogenically removed. Recuperation of CO2 >99%. Similar results for CO2 levels as in the previous method. See page 6 of:
http://courses.washington.edu/proxies/GHG.pdf
winterkorn says:
August 21, 2010 at 9:07 am
The old saw that extraordinary claims require extraordinary proof should have a couple of corollaries:
1. claims that run counter to common sense require extraordinary proof
2. claims that support secondary gain for the presenter require extraordinary proof.
In the case of atmospheric CO2 and human emissions #1 above is partly invoked (I am not invoking #2 in this posting; I do not think it is an issue here). If it is true that human CO2 production is only 4% of total production, then common sense indicates that a relatively small change in the other 96% (which must be biological, for the most part) could overwhelm any human change. For example a few percent change in CO2 production from the huge reservoirs of biologically available carbon (rotting vegetation, peat, coal, oil seeps, etc) could produce big changes in the overall flows in the Earth’s CO2 cycle.
The huge increases in CO2 during some interglacials in the past came from somewhere, as yet not known with certainty.
So long as these sorts of issues remain, the truth about effects of human production of CO2 should be considered as in some doubt.
Sorry for the delay in reaction…
Well point 2 is no problem: I am not badly paid by a (until now) solid pension fund.
About point 1:
That can be used the other way out too: If the human emissions are double the observed increase in the atmosphere, then claims that run counter to common sense, like that humans are not responsible, require extraordinary proof…
But your question is quite simply answered: the observed variability of the natural carbon balance is about +/- 2 GtC around the trend. That can be seen as the variability in the increase in the atmosphere, because the emissions show far less variability. The main driver of the variability is (ocean) temperature, which influences the sink rate of the oceans and opposite the growth rate of vegetation. As these two are opposite influences, the net effect is quite small (about 4 ppmv/°C), despite the huge fluxes involved.
The huge differences over glacials/interglacials have mainly the same sources, but additional: ice sheet building, at the cost of vegetation area and changes in (deep) ocean flows. Not all details are known, but the effect is: some 8 ppmv/°C between warm and cold periods. By far not enough to explain the current 100+ ppmv rise for 1°C rise in temperature since the LIA.
Bart says:
August 21, 2010 at 12:44 pm
you do not see any broad correlation between human inputs and actual CO2 measurements. I have done the analysis. There are no discernible overlapping periodicities between human production and the measurements.
Mike Jonas says:
August 22, 2010 at 8:06 am
You might be interested in these graphs, which might indicate that changes in CO2 concentration are driven by tropical temperatures, with quite rapid mixing across the hemispheres.
http://members.westnet.com.au/jonas1/CO2NorthAndSouth.pdf
And some others with similar remarks…
There is a quite good correlation between (ocean) temperature and increase rate in the atmosphere, far less between temperature and increase of CO2 in the atmosphere. Many, warmers and skeptics alike, agree on that.
But what you are doing is looking at the derivative of the trend, where most of the trend (caused by the relative constant emissions) is removed and temperature is the dominant driver of the variability. But a derivative of a trend doesn’t say anything about the cause of the trend itself…
Thus please have a look at the accumulation in the atmosphere and the accumulated emissions, not the year-by-year emissions and increase in the atmosphere:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/acc_co2_1900_2004.jpg
and compare that with the influence of temperature:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_co2_1900_2004.jpg
Richard S Courtney says:
August 24, 2010 at 1:45 am
Do you have a reference for your “quasi-equilibrium” statement? I was curious about your example of concrete, and found a lot of literature which doesn’t support your statement. You said:
As an illustration, I point out that this reduction of diffusion rate is why steel can be used as reinforcement in concrete. Iron oxide is about four times larger than the oxidised iron. So, if steel rusts it breaks the concrete. (Many people have seen a concrete fence post that has been destroyed by rusting of its internal steel reinforcement that is close to the post’s surface). But if the concrete’s steel reinforcement is about 10 cm or more from the concrete surface then the steel does not rust. This is because the diffusion rate decreases to almost nothing when the partial pressure gradient at the tip of the diffusing oxygen becomes very small, and the partial pressure gradient reduces with distance from the high partial pressure at the concrete surface.
While that may true, it seems that the diffusion goes on indefinitely, but the migration rate decreases with the distance in the concrete. The chemical reactions of the concrete with CO2 (which also influences rust formation) neutralises the high pH of the cement. The layer thickness with which that occurs is increasing with the square root of the period involved. The speed varies with porosity, temperature and humidity between 0.5 and 15 mm/sqrt(years). Humidity plays a strange role: highest humidity hinders CO2 migration because of the presence of liquid water in the pores (I learn new things every day!). Relative high humidity gives the highest reaction speed, and low humidity prevents the reaction of CO2 with the cement. See:
http://www.nordicinnovation.net/_img/03018_the_co2_balance_of_concrete_in_a_life_cycle_perspective_final_report1.pdf
No, I don’t know more about ice than the next guy other than having a BS Chem degree. But I do know how to Google and I’m a bit disappointed that people don’t do more research when they argue here. It would be really great to have access to the scientific literature for free, but that ain’t happening for me. It looks like the crystalline structure of the most common form of ice, out of 15 known forms, does not have big enough voids to accommodate a CO2 molecule. So if there is any path it would have to be along grain boundaries or outright cracks. Also, it seems CO2, if it could move, might migrate from higher to lower pressure – but do not know this for sure.
Ferdinand Engelbeen : “There is a quite good correlation between (ocean) temperature and increase rate in the atmosphere, far less between temperature and increase of CO2 in the atmosphere. Many, warmers and skeptics alike, agree on that.”
I agree too – see my first post on this thread “I have worked through the figures for both ocean temperature and THC in multiple ways, and am now satisfied that their contribution to atmospheric CO2 is small compared to fossil fuel emisions. I am not satisfied with my own findings, because they do nothing to explain the long term CO2 lag [does anyone have an explanation for it?], but they do lead me to accept that F.E. is correct.” [emphasis added here]
So I was obviously not arguing that temperature was more important than CO2 re increase in CO2 over the last few decades. What I was arguing was that the graphs I posted seemed to indicate that CO2 did mix across the hemispheres.
Ferdinand Engelbeen : “Well, the increase in temperature certainly added more CO2 to the total natural input flows, but it didn’t add to the increase, as the total natural outflows were larger”
You still don’t get it. In the absence of fossil fuel emissions, the increase in temperature would have caused atmospheric CO2 to increase. I don’t think there is any disagreement on that – you accept that increasing temperatures caused CO2 to increase by 8ppm or 16ppm since the LIA. If we call the observed CO2 increase over the last 50 years “100%”, then, if there had been no fossil fuel emissions, we would probably have had (from my calcs) at least a “5%” CO2 increase, possibly “16%” (using your 16ppm figure), and an unspecified amount more or less than that because some of my assumptions (such as linear relationships) might have been invalid. Therefore, even though nature was in fact a net sink of CO2, the contribution of fossil fuel emissions to atmospheric CO2 was actually less than “100%”. It seems counter-intuitive, that a net sink can contribute to the increase, but it is so. The reason is that the CO2 added to the atmosphere from fossil fuels causes the concentration to be greater than that which the temperature increase would have caused, and therefore the oceans absorb some of it. But without the temperature increase the exact same fossil fuel emissions would not have caused the CO2 concentration to increase by as much.
Without the emissions, CO2 would have gone up.
Without the temperature increase, CO2 would have gone up by less.
No matter how you look at it, there has indeed been a natural contribution to the level of CO2 concentration over the last 50 years.
Correction – for “16%” read “12%”
Mike Jonas
I agree with your comment at 1.43 but would add that the actual observed surface temperature rise and its effects on Co2 concentrations need to be considered with that of ocean variabilty.
It is said that there is a 8ppm outgasing for every 1Degree rise of the ocean temperature.
http://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/
If the LIA was generally a world wide event, with its effects proably greater in higher latitudes than the tropics, it is likely that the LIA ocean temperatures in many parts of the world would, at times, have been very much less than 1 degree cooler than today’s ‘average’ values. Therefore there should have been a notable dip in Co2 in such proxies as ice cores, then a subsequent increase as ocean temperatures subsequently picked up by (presumably) several degrees.
Generally we know that the Arctic and Antarctic SST’s appear to be largely out of sync with each other, thereby to some extent cancelling out some of the effects, but there are times in recorded history -such as the 1930’s- when they were in sync and doubtless this has happened before.
This synchronicity plus the extreme climatic effects of such events as the LIA and MWP should all have had a discernible effect on ocean temperatures and subsequent CO2 concentrations, but the signal appears to be missing.
We are talking pre Keeling here of course, as since the Mauna Loa readings there has been a steady increase without the peaks and troughs that would be expected in more climatically varied times.
Tonyb
Richard S Courtney says:
August 24, 2010 at 1:45 am
In addition, if we may assume that the migration of CO2 through the ice is comparable to the migration rates through concrete, the distance reached over each period of 100,000 years back in time, starting with current CO2 levels would be:
150, 220, 270 and 310 mm if the pores are very small.
4, 6.7, 8.2 and 9.4 meter if the pores are wider.
There are of course differences between concrete and ice: at one side concrete uses CO2 for the chemical reaction, but that also makes that the pressure difference is maintained until the cement in concrete is neutralised, while CO2 in ice has only the partial pressure difference. At the othes side, ice pores are much finer if not (near) absent at -40°C…
Mike Jonas says:
August 25, 2010 at 1:43 am
Sorry, I didn’t look at the context of your graphs…
But without the temperature increase the exact same fossil fuel emissions would not have caused the CO2 concentration to increase by as much.
I did get it, but you are right and wrong: indeed the increase in temperature did increase the input and highly probably caused an extra increase in total CO2, by reducing the sink rate. But at the other side, the extra input is halved, because the outputs increased too (mainly by the human emissions, a small part by the extra input from the temperature increase… E.g. the uptake by vegetation increases with temperature and humidity. Thus if we look at that extra outflow, that increases the total of the outflows and probably reduced the increase rate. Thus without the extra output, CO2 levels would have increased faster…
One can have different opinions, simply because the way you look at it, separate or combined, makes a huge difference.
Further, you look at one (net) input in isolation, only because we have a pretty good idea what CO2 levels in general do with changes in temperature. Other flows and their variations are less known.
But I find it a rather academic discussion if it is 92% or 96% or 100% which is caused by human emissions. Others go much farther as they say that human emissions are only 4% of the total input (which is right), thus only 4% of the increase (which is wrong as we are talking about increase in mass, not what fraction of molecules is coming from human emissions).
tonyb says:
August 25, 2010 at 4:30 am
This synchronicity plus the extreme climatic effects of such events as the LIA and MWP should all have had a discernible effect on ocean temperatures and subsequent CO2 concentrations, but the signal appears to be missing.
We are talking pre Keeling here of course, as since the Mauna Loa readings there has been a steady increase without the peaks and troughs that would be expected in more climatically varied times.
Hello Tony,
The MWP-LIA difference is visible in the best resolution ice core (21 years average) from Law Dome, spanning that period:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_1000yr.jpg
There was a clear dip of about 6 ppmv around 1600, about 50 years later than the onset of the coldest period of the LIA.
As one expect a maximum 0.8°C temperature dip (depends of what reconstruction you take into account) in that period, the sensitivity of CO2 for temperature changes is about 8 ppmv/°C, about the same found in very long term changes over the ice ages. The current short term sensitivity (over 1-2 years) is about 4 ppmv/°C around the trend…
“There was a clear dip of about 6 ppmv around 1600, about 50 years later than the onset of the coldest period of the LIA.”
In other words: changes in CO2 are the result of temperature changes.
#
Mike Jonas says:
August 25, 2010 at 1:43 am
In the absence of fossil fuel emissions, the increase in temperature would have caused atmospheric CO2 to increase.
—–
Since the increase in temperature over the last 50 years was likely caused by greenhouse gases, then you could argue that fossil fuel etc burning is responsible for 105% of the observed increase.
Ferdinand
There may have been a .8C Average temperature dip on land (although that is highly debatable) but the oceanic temperature would have eventually dipped much more than that in the real world. For example the distribution of fish is a good proxy indicator and during the LIA we switched from Pilchard to Cod thereby assuming a sea temperature change of several degrees, not a fraction of one.
Again, in the real world, during the LIA the waters in many higher latitude countries-such as the UK or Holland-would certainly be many degrees lower than they are at present. It is pouring with rain outside today and the English Channel 100 yards from my house is still only 17C even though this is the ‘hottest year ever’. In the coldest year ever it is unlikely to have been within 5 degrees of this temperature.
The ice cores should present more spikes than appear to be present to reflect the LIA and MWP.
Also, as Smokey observes, surely this demonstrates that CO2 follows temperature changes, but rather quicker than the 800 years commonly cited?
Tonyb
Smokey says:
August 25, 2010 at 6:35 am
“There was a clear dip of about 6 ppmv around 1600, about 50 years later than the onset of the coldest period of the LIA.”
In other words: changes in CO2 are the result of temperature changes.
Agreed, even nowadays: there is an influence of temperature on CO2 trends (about 4 ppmv/°C), but that doesn’t exclude that CO2 has some influence on temperature. In how far, that remains to be seen.
tonyb says:
August 25, 2010 at 7:27 am
Ferdinand
There may have been a .8C Average temperature dip on land (although that is highly debatable) but the oceanic temperature would have eventually dipped much more than that in the real world. For example the distribution of fish is a good proxy indicator and during the LIA we switched from Pilchard to Cod thereby assuming a sea temperature change of several degrees, not a fraction of one.
Mostly, it is that land temperatures change more that sea surface temperatures. And fish indeed reacts on sea surface temperature, but in this case it seems that the Gulf stream changed direction (as Mörner claims) more southwards (around Portugal, later North Africa) leaving the whole North with colder seas.
The ice cores should present more spikes than appear to be present to reflect the LIA and MWP.
Also, as Smokey observes, surely this demonstrates that CO2 follows temperature changes, but rather quicker than the 800 years commonly cited?
The ice cores present spikes that are high enough or sustained long enough for the resolution they have. The short Law Dome ice cores (150 years) can show any one-year spike of 20 ppmv or a 10 years sustained in/decrease of 2 ppmv (accuracy 1.2 ppmv – 1 sigma, resolution 8 years), but Vostok needs a sustained in/decrease of 5 ppmv over 600 years, or 50 ppmv over 60 years. That is no problem to show the large variations between glacials and interglacials, as these cover periods of many thousands of years, but faster, smaller changes are not visible.
The 800 years lag is what is seen following the increase of temperature at a deglaciation. But the lag is many thousands of years when temperatures fall again.
The length of the lag of deglaciations may be connected to (deep) ocean flows, freeing land from ice sheets, increasing land cover by vegetation,… The opposite lag length seems correlated to the duration of the warm period: the longer/hotter, the longer the lag, may have to do with the amount of carbon sequestered by vegetation which is again decayed by soil bacteria.
The LIA was relative short duration, compared to ice ages, thus not much time to deeply change vegetation or deep ocean currents or ice sheets to build up.
Ferdinand
Ferdinand.
You said;
” That is no problem to show the large variations between glacials and interglacials, as these cover periods of many thousands of years, but faster, smaller changes are not visible.”
That’s an interesting comment which surely gets to the heart of our concerns as to the reality of ice cores as proxies of accurate measurements, as opposed to actual atmospheric records taken at the time.
It is the sea surface that is in contact with the atmosphere and the temperature of that medium changes very quickly and will outgas or absorb CO2. Deep ocean is much less susceptible to temperature change on an annual/decadil basis.
The LIA was typifed by short violent changes between very cold weather and temperatures similar to today, and even looking at the modern record we can see periods of cooling e.g the 1970’s in between the general warming.
Surely the logic of what you appear to be saying is that ice cores are unable to pick up these short sharp spikes of temperature, which presumably would result in short sharp spikes of co2? It is in effect ‘smoothed’ to an unrealistic extent, whereas in the real world it would surely be much spikier (just like land temperature records look totally different in their natural and smoothed states)?
I often wonder what was the effect on oceanic currents when the Dogger Bank became part of the North Sea after the last ice age and Britain became an island instead of part of the land mass.
Tonyb
tonyb, F.E., Smokey, richard telford : thanks for your comments. I do not claim to have all the answers, but I did feel it was important to establish that factors other than fossil fuel emissions affect the level of CO2 over all time frames.
tonyb, F.E. – I doubt that the “8ppm outgasing for every 1Degree rise” is a linear relationship. A really interesting feature of the observed data (atmospheric CO2 concentration “A” and temperature “T“) is that there is a closer relationship between dA and T than there is between dA and dT. This suggests to me that it is very possible that the relationship between dA and dT is not linear, and that unconsidered other factors may come into play. An area that could be worth looking at is the behaviour of CO2 in seawater – it does not just dissolve, it is involved in chemical reactions and biological activity which alters the ability of CO2 that has been absorbed in cooling seawater to be available for re-release when the seawater warms up again.
Until we understand the 800-year time lag [and a few other things], surely we don’t know what is really going on.
F.E. : “I find it a rather academic discussion if it is 92% or 96% or 100% which is caused by human emissions”
Yes and no. As I said, we cannot be sure that the real number is not 88% or less. I do think that it is high, probably well over 90%, but I cannot prove it. The important thing is to recognise that this factor exists, and to make proper allowance for it.
richard telford : yes, the extent to which CO2 affects temperature does affect the equation. At an ECS below 1 the impact is minor, at the IPCC’s 3.2 it is much greater. The calculations are not particularly difficult, and I can assure you that no matter what ECS you plug in the effect of emissions is still less than 100%!
tonyb says:
August 25, 2010 at 12:03 pm
Dear Tony,
The fast spikes, if caused by (surface) oceans only, have not so much influence: the solubility curve of CO2 in seawater is about 16 ppmv/°C, if the whole ocean surface layer warms up in that way. At the other side, more CO2 in the atmosphere and higher temperatures increases plant growth, including in the oceans, which reduces the increase. Thus the 8 ppmv/°C are not far off.
Further, if the the change in Gulf Stream was one of the causes (which might have been the result of less driving force by the spotless, inactive sun), that could give cold weather in our countries, but caused warmer weather first in Portugal, later in North Africa. Thus the overall sea surface temperatures need not be much colder.
The reconstructions with the largest difference in temperature MWP-LIA (or LIA-CWP) show some 0.8°C difference, of which one is based on tree rings (Esper), one is boreholes (Huang) and one is mixed (Moberg), the latter used several ocean sediments and the influence of tree rings is reduced. Although all three have their problems and errors, the general impression is that global temperature differences were not much larger than that.
In how far ice cores pick up real spikes is mainly a matter of accumulation rate: The more snowfall, the faster the air in between is sealed and the less spread in years you have in averaging the CO2 levels. The backdraw is that more accumulation means thicker layers and a shorter duration of the full period, as one reaches the rock bottom. Thus for the fastest accumulating Law Dome ice cores, one can only look back some 150 years. The third core, which was taken more downslope goes back some 1,000 years and the longest, Dome C, goes back some 800,000 years.
Thus fast changes like El Niño/La Niña periods will not be noticed in even the fastest ice cores, neither the Pinatubo eruption. But you may be sure that if there was any increase and decrease of 80 ppmv between 1935-1950, that would be visible in the fast Law Dome ice cores (and even in the slower one), as a Gaussian peak value of at least 60 ppmv spread over a period of some 20 years.
Further, averaging doesn’t change the average: a peak must be followed by an equal level of low values to give the average as found in the ice core…
As far as we see in the Mauna Loa and other stations data of the past 50 years, the mainly temperature controlled variability around the trend, as well as from the seasons as from spikes like an El Niño is some 4 ppmv/°C, not really huge… One need very huge worldwide temperature changes like a glacial-interglacial transition, to give a natural change of 100 ppmv.
I am sure that the fact that England now is an island has a huge effect on the psychology of the people living there, not sure if that makes much difference in climate, as in general we receive the same bad weather, be it somewhat later (it just starts raining here…).
Mike Jonas says:
August 25, 2010 at 12:57 pm
I doubt that the “8ppm outgasing for every 1Degree rise” is a linear relationship. A really interesting feature of the observed data (atmospheric CO2 concentration “A” and temperature “T“) is that there is a closer relationship between dA and T than there is between dA and dT. This suggests to me that it is very possible that the relationship between dA and dT is not linear, and that unconsidered other factors may come into play.
The solubility coefficient of CO2 in seawater indeed is not linear, but that doesn’t stop there. There is some factor 4 increase in pCO2 pressure of seawater between the poles near 0°C and the equator near 30°C. On the other hand, biological activity reduces the pCO2 from the poles to the equator. Thus these two factors are opposite. And we have more vegetation growth and thus carbon sequestering with higher temperatures. That all makes that we see a remarkably linear response of CO2 levels to temperature over the ice ages.
The current T/A rate around the trend is more related with the vegetation response to temperature and precipitation than by the oceans (these may be the cause of the temperature changes, but CO2 responds faster on vegetation – see the seasonal changes). See
http://esrl.noaa.gov/gmd/co2conference/pdfs/tans.pdf from page 11 on.
And while the pCO2 of ocean surface and atmosphere seek an equilibrium, a doubling of CO2 in the atmosphere only increases the CO2-bi-carbonate content of the oceans surface with 10%, due to the change in pH.
I still disagree with the less than 100%… If we may assume that the current natural sink rate is directly related to the difference in pCO2 between the current levels and the “equilibrium” level, dictated by temperature changes, then the increase in temperature since the LIA indeed has changed the equilibrium level somewhat, decreasing the sink rate, but that still is no contribution to the increase itself. Stop the emissions, and there is a quite certain drop in CO2 levels in the next years, despite an increased temperature, until we are back to equilibrium…
F.E. : I find it hard to accept that “we see a remarkably linear response of CO2 levels to temperature over the ice ages” and “I still disagree with the less than 100%” are compatible.
I have no difficulty agreeing with “Stop the emissions, and there is a quite certain drop in CO2 levels in the next years, despite an increased temperature” [provided that the temperature does not increase by too much, of course]. But in making that statement I must point out two things: (1) We have always implicitly agreed on that. The dispute concerns by how much since, as you say, it would be “dictated by temperature changes” – which is the basis of my case. (2) My statement is made in a scientific context, not a political context; in a political context, I would argue that there are far far better things to do than stop the emissions.
And I still want to know the mechanisms behind the 800-year lag.
Mike Jonas says:
August 26, 2010 at 5:31 pm
F.E. : I find it hard to accept that “we see a remarkably linear response of CO2 levels to temperature over the ice ages” and “I still disagree with the less than 100%” are compatible.
The endpoint (equilibrium) shifts somewhat with temperature, but we are already 100 ppmv above equilibrium. No matter of that in reality is 90 or 110 ppmv, there is no real contribution of temperature to the increase, only a contribution to the sink rate.
For your own bussiness, it doesn’t matter that others also have contributed to the gain of the bank (even if their contribution was higher than yours), if the gain at the end of the year is less than what your own contributions during the year where: better look for another bank…
(2) My statement is made in a scientific context, not a political context; in a political context, I would argue that there are far far better things to do than stop the emissions.
Ditto.
And I still want to know the mechanisms behind the 800-year lag.
Probably caused by the app. 800 years mixing time with the deep oceans, see:
http://icebubbles.ucsd.edu/Publications/CaillonTermIII.pdf
F.E. : Thanks for the link on the lag. I will read.
About your unprofitable bank : We are talking about a rather unusual bank. This bank has two divisions, and the more profit that division A makes (emissions into the atmosphere), the more difficult it makes it for the division B (emissions from warming oceans) to make a profit. So profitable has division A become, that it has forced division B into making big losses. So, as you correctly state, all the profit comes from division A. But now there is a threat to division A and the bank may be forced to close it down (stop emissions). Investors shorting the bank are thrilled “all their profits come from division A, if division A closes down the bank will make no profit at all”. But of course, they are wrong – if division A closes, then the bank will make a profit again from division B.
Mike Jonas says:
August 27, 2010 at 2:46 pm
if division A closes, then the bank will make a profit again from division B.
But not immediately, only after many years, when the buildup of capital from division A is (near) completely gone…
RE: Ferdinand Engelbeen: (August 21, 2010 at 7:07 am) “Hardly any, as what animals respire has been captured some months/years before. Some carbon is temporarely stored in fat tissues, but that is very small, compared to what is stored in vegetation in general.
As I understand it, you are saying that even if a massive decline of the primary CO2 emitting biota (animals) relative to oxygen emitting biota (plants) did happen during a cold period, that would not cause the CO2 levels to fall because of the continuing release of CO2 from decaying vegetation. Is it possible that the colder temperatures would slow down those decay rates? Perhaps the issue is moot because no such plant/animal imbalance ever happens.
Ferdinand Engelbeen says: August 24, 2010 at 2:27 am
“The refresh rate of 150 GtC doesn’t change the total mass in the atmosphere, it only governs how much red CO2 resides there, it is only the imbalance which adds or removes CO2 from the total mass in the atmosphere.”
Sorry to come back to the material balance again, because I think that your reasoning still contains a flaw.
It is obvious that if the refreshment rate 150 GtC/y is constant, it will not change the total mass in the atmosphere. But the basis for the assumption that a natural source is contributing to the increase of the total mass in the atmosphere, is that the refreshment rate is not constant. It is at least not over a short time interval of years. The increase of CO2 in the atmosphere Fa (GtC/y) fluctuates from 1.5 to 5.5 GtC/y. Fluctuations are the result of the difference of the flow Fin at the source and the Fout at the sinks. Both are independently influenced by other forces than the actual CO2 concentration in the atmosphere alone. Let’s assume an ‘average’ flow in, which equals the flow out, and add to both a variability dFin and dFout, the addition to the atmosphere Fa = (150 + dFin) – (150+dFout) = dFin – dFout.
Next we add to the atmosphere an extra anthropogenic flow Fem, then Fa reads:
[1] Fa = Fem+dFin – dFout
Fem consists of aC, dFin of CO2 from the natural source nC.
In your way of reasoning, you say Fa= 0.5 times the value of Fem, thus dFin-dFout = – 0.5 times of the value of Fem. If we introduce for Fem = 7 GtC/y (near year 2000).
Fa= 3.5 and dFin-dFout = -.3.5. Thus dFin must be smaller than dFout and I read from your figure 3 in part one you even indicated that dFin is lower than 0. But I suppose that this has not been measured and that you reach this conclusion by calculation to balance the equation [1] to make dFout less than 3.5 . That is the problem with the solution of one equation with two unknowns (dFin and dFout).
Solutions for -3.5 = dFin-dFout can be
[a] dFin = -3 dFout = 0.5
[b] dFin= 0 dFout = 3.5
[c] dFin = + 3 dFout = 6.5
The difference between [a] and [c] is in words, that in [a] the Fa was reduced below the value of Fem by a required small increase of dFout, and that in [c] the contribution of dFin requires a considerable increase of dFout to keep the value Fa below the value of Fem. Your way of reasoning to favor [a] (or [b] ) over [c], with the argument that dFin-dFout must be negative to reduce the value of Fa below Fem, I still fail to understand because in all three assumptions this is the case.
I am not excluding either [a] beforehand. The change of dFout depends on what distance the system is operating from its assumed equilibrium state Fin=Fout.
Previously I have rewritten in the equation [1] the dFout as containing a fraction x of what is coming in as Fem and dFin
[2] dFout = x*(Fem+dFin)
because the sink will not discriminate between aC and nC
Then [1] reads
[3] Fa= (Fem+dFin) – x(Fem+dFin) = (Fem+dFin)*(1-x)
In [2]
Case 1: with dFin =0, x becomes 0.5 .
But if I have interpreted your view correctly,
Case 2. dFin should be negative and it requires that x is lower than 0.5. It means that less of the in flow than half of it, can be removed. Thus there is a strong constraint on the absorption of extra in flows. The system operates near a saturation level for removal of CO2 from the atmosphere. .
Case 3. If dFin is positive, than x is greater then 0.5. It means that more than half of the inflow can be removed. Thus there is no strong constraint on the extra in flows. The system operates away from its saturation level.
In summary,
Case 1 is a rather arbitrary assumption
Case 2 needs proof that there is a strong constraint on the extra inflows and that dFin is negative
Case 3 needs proof that there is little constraint and that dFin is positive.
At least we can say that the system is not already at a specific (natural) saturation level, otherwise all of the Fem would be accumulating in the atmosphere.
Arthur Rörsch
Arthur Rörsch says:
August 29, 2010 at 7:25 am
Dear Arthur,
You wrote:
Your way of reasoning to favor [a] (or [b] ) over [c], with the argument that dFin-dFout must be negative to reduce the value of Fa below Fem, I still fail to understand because in all three assumptions this is the case.
I have not the slightest preference for [a] or [b] or [c]. Even have I no problems if
dFin = +10, dFout = +13.5
thus dFin in that case is larger than Fem. As in all cases, dFout is 3.5 GtC larger than dFin for the year 2000, because that is what is calculated as the difference between increase in the atmosphere and emissions.
That indeed doesn’t change the mass balance: dFin increased, but dFout (need to be) increased with the same amount, thus while the input flows increased with dFin, the total mass in the atmosphere, Fa, didn’t change by one gram of CO2, despite the increase of total inflow Fin.
The only effect of the increase of total input caused by dFin is that the throughput, the refresh rate, increased from some 150 GtC to 160 GtC. Thus the replacement of “red” aCO2 by nCO2 is accellerated and a larger fraction (than 0.5) of aCO2 is removed from the atmosphere. But still the emissions are fully responsible for the increase, as that is the only real addition to the total mass. How much of the original aCO2 remains as fraction, even if all aCO2 was completely replaced by nCO2 within a year, that has not the slightest interest for the total mass of CO2 present in the atmosphere…
In the past 50 years there was always a net sink of all natural flows and these only show a moderate variability of Fin and Fout combined: +/- 2 GtC from year to year around the trend of nowadays +4 GtC/year, halve the emissions of +8 GtC/year.