Studies of Carbon 14 in the atmosphere emitted by nuclear tests indicate that the Bern model used by the IPCC is inconsistent with virtually all reported experimental results.
Guest essay by Gösta Pettersson
The Keeling curve establishes that the atmospheric carbon dioxide level has shown a steady long-term increase since 1958. Proponents of the antropogenic global warming (AGW) hypothesis have attributed the increasing carbon dioxide level to human activities such as combustion of fossil fuels and land-use changes. Opponents of the AGW hypothesis have argued that this would require that the turnover time for atmospheric carbon dioxide is about 100 years, which is inconsistent with a multitude of experimental studies indicating that the turnover time is of the order of 10 years.
Since its constitution in 1988, the United Nation’s Intergovernmental Panel on Climate Change (IPCC) has disregarded the empirically determined turnover times, claiming that they lack bearing on the rate at which anthropogenic carbon dioxide emissions are removed from the atmosphere. Instead, the fourth IPCC assessment report argues that the removal of carbon dioxide emissions is adequately described by the ‘Bern model‘, a carbon cycle model designed by prominent climatologists at the Bern University. The Bern model is based on the presumption that the increasing levels of atmospheric carbon dioxide derive exclusively from anthropogenic emissions. Tuned to fit the Keeling curve, the model prescribes that the relaxation of an emission pulse of carbon dioxide is multiphasic with slow components reflecting slow transfer of carbon dioxide from the oceanic surface to the deep-sea regions. The problem is that empirical observations tell us an entirely different story.
The nuclear weapon tests in the early 1960s have initiated a scientifically ideal tracer experiment describing the kinetics of removal of an excess of airborne carbon dioxide. When the atmospheric bomb tests ceased in 1963, they had raised the air level of C14-carbon dioxide to almost twice its original background value. The relaxation of this pulse of excess C14-carbon dioxide has now been monitored for fifty years. Representative results providing direct experimental records of more than 95% of the relaxation process are shown in Fig.1.
Figure 1. Relaxation of the excess of airborne C14-carbon dioxide produced by atmospheric tests of nuclear weapons before the tests ceased in 1963
The IPCC has disregarded the bombtest data in Fig. 1 (which refer to the C14/C12 ratio), arguing that “an atmospheric perturbation in the isotopic ratio disappears much faster than the perturbation in the number of C14 atoms”. That argument cannot be followed and certainly is incorrect. Fig. 2 shows the data in Fig. 1 after rescaling and correction for the minor dilution effects caused by the increased atmospheric concentration of C12-carbon dioxide during the examined period of time.
Figure 2. The bombtest curve. Experimentally observed relaxation of C14-carbon dioxide (black) compared with model descriptions of the process.
The resulting series of experimental points (black data i Fig. 2) describes the disappearance of “the perturbation in the number of C14 atoms”, is almost indistinguishable from the data in Fig. 1, and will be referred to as the ‘bombtest curve’.
To draw attention to the bombtest curve and its important implications, I have made public a trilogy of strict reaction kinetic analyses addressing the controversial views expressed on the interpretation of the Keeling curve by proponents and opponents of the AGW hypothesis.
(Note: links to all three papers are below also)
Paper 1 in the trilogy clarifies that
a. The bombtest curve provides an empirical record of more than 95% of the relaxation of airborne C14-carbon dioxide. Since kinetic carbon isotope effects are small, the bombtest curve can be taken to be representative for the relaxation of emission pulses of carbon dioxide in general.
b. The relaxation process conforms to a monoexponential relationship (red curve in Fig. 2) and hence can be described in terms of a single relaxation time (turnover time). There is no kinetically valid reason to disregard reported experimental estimates (5–14 years) of this relaxation time.
c. The exponential character of the relaxation implies that the rate of removal of C14 has been proportional to the amount of C14. This means that the observed 95% of the relaxation process have been governed by the atmospheric concentration of C14-carbon dioxide according to the law of mass action, without any detectable contributions from slow oceanic events.
d. The Bern model prescriptions (blue curve in Fig. 2) are inconsistent with the observations that have been made, and gravely underestimate both the rate and the extent of removal of anthropogenic carbon dioxide emissions. On basis of the Bern model predictions, the IPCC states that it takes a few hundreds of years before the first 80% of anthropogenic carbon dioxide emissions are removed from the air. The bombtest curve shows that it takes less than 25 years.
Paper 2 in the trilogy uses the kinetic relationships derived from the bombtest curve to calculate how much the atmospheric carbon dioxide level has been affected by emissions of anthropogenic carbon dioxide since 1850. The results show that only half of the Keeling curve’s longterm trend towards increased carbon dioxide levels originates from anthropogenic emissions.
The Bern model and other carbon cycle models tuned to fit the Keeling curve are routinely used by climate modellers to obtain input estimates of future carbon dioxide levels for postulated emissions scenarios. Paper 2 shows that estimates thus obtained exaggerate man-made contributions to future carbon dioxide levels (and consequent global temperatures) by factors of 3–14 for representative emission scenarios and time periods extending to year 2100 or longer. For empirically supported parameter values, the climate model projections actually provide evidence that global warming due to emissions of fossil carbon dioxide will remain within acceptable limits.
Paper 3 in the trilogy draws attention to the fact that hot water holds less dissolved carbon dioxide than cold water. This means that global warming during the 2000th century by necessity has led to a thermal out-gassing of carbon dioxide from the hydrosphere. Using a kinetic air-ocean model, the strength of this thermal effect can be estimated by analysis of the temperature dependence of the multiannual fluctuations of the Keeling curve and be described in terms of the activation energy for the out-gassing process.
For the empirically estimated parameter values obtained according to Paper 1 and Paper 3, the model shows that thermal out-gassing and anthropogenic emissions have provided approximately equal contributions to the increasing carbon dioxide levels over the examined period 1850–2010. During the last two decades, contributions from thermal out-gassing have been almost 40% larger than those from anthropogenic emissions. This is illustrated by the model data in Fig. 3, which also indicate that the Keeling curve can be quantitatively accounted for in terms of the combined effects of thermal out-gassing and anthropogenic emissions.
Figure 3. Variation of the atmospheric carbon dioxide level, as indicated by empirical data (green) and by the model described in Paper 3 (red). Blue and black curves show the contributions provided by thermal out-gassing and emissions, respectively.
The results in Fig. 3 call for a drastic revision of the carbon cycle budget presented by the IPCC. In particular, the extensively discussed ‘missing sink’ (called ‘residual terrestrial sink´ in the fourth IPCC report) can be identified as the hydrosphere; the amount of emissions taken up by the oceans has been gravely underestimated by the IPCC due to neglect of thermal out-gassing. Furthermore, the strength of the thermal out-gassing effect places climate modellers in the delicate situation that they have to know what the future temperatures will be before they can predict them by consideration of the greenhouse effect caused by future carbon dioxide levels.
By supporting the Bern model and similar carbon cycle models, the IPCC and climate modellers have taken the stand that the Keeling curve can be presumed to reflect only anthropogenic carbon dioxide emissions. The results in Paper 1–3 show that this presumption is inconsistent with virtually all reported experimental results that have a direct bearing on the relaxation kinetics of atmospheric carbon dioxide. As long as climate modellers continue to disregard the available empirical information on thermal out-gassing and on the relaxation kinetics of airborne carbon dioxide, their model predictions will remain too biased to provide any inferences of significant scientific or political interest.
References:
Climate Change 2007: IPCC Working Group I: The Physical Science Basis section 10.4 – Changes Associated with Biogeochemical Feedbacks and Ocean Acidification
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-4.html
Climate Change 2007: IPCC Working Group I: The Physical Science Basis section 2.10.2 Direct Global Warming Potentials
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-10-2.html
GLOBAL BIOGEOCHEMICAL CYCLES, VOL. 15, NO. 4, PAGES 891–907, DECEMBER 2001 Joos et al. Global warming feedbacks on terrestrial carbon uptake under the Intergovernmental Panel on Climate Change (IPCC) emission scenarios
ftp://ftp.elet.polimi.it/users/Giorgio.Guariso/papers/joos01gbc[1]-1.pdf
Click below for a free download of the three papers referenced in the essay as PDF files.
Paper 1 Relaxation kinetics of atmospheric carbon dioxide
Paper 2 Anthropogenic contributions to the atmospheric content of carbon dioxide during the industrial era
Paper 3 Temperature effects on the atmospheric carbon dioxide level
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Gösta Pettersson is a retired professor in biochemistry at the University of Lund (Sweden) and a previous editor of the European Journal of Biochemistry as an expert on reaction kinetics and mathematical modelling. My scientific reasearch has focused on the fixation of carbon dioxide by plants, which has made me familiar with the carbon cycle research carried out by climatologists and others.
The original post is about the faster rate of elimination of human emissions than recognised by the IPCC.
It is clear from the example given that residence time is shorter than suggested for individual molecules and the pulse removal time is faster.
In reality our emissions are not as a pulse, they increase over time but nonetheless the IPCC is wrong.
The data available suggests no observable high levels of CO2 over or downwind of inhabited land areas yet there are such observable high levels over and downwind of sunlit oceans.
ROM said:
“also due to the release or uptake or the out-gassing of CO2 by the atmospheric water vapour as the atmospheric temperatures change as the season’s change ?”
Murry Salby also suggests soil moisture on land as a significant player.
jkanders says:
July 2, 2013 at 2:21 am
The Bern model describes the amount of this change in leakage.
The author here talks about the magnitude of the leakage.
You seem to be ignoring this statement in the OP:
c. The exponential character of the relaxation implies that the rate of removal of C14 has been proportional to the amount of C14. This means that the observed 95% of the relaxation process have been governed by the atmospheric concentration of C14-carbon dioxide according to the law of mass action, without any detectable contributions from slow oceanic events.
Also worth remembering that while an increase in temperature may push an equilibrium position in one direction, if the system is already significantly displaced away from the current potential equilibrium position, the temperature effect will usually increase the RATE at which the system is changing. That change may be in the opposite direction to that expected for the change in the equilibrium position. This can produce counter-intuitive results even in a simple system.
And then there’s the biology… For good reasons, ~100% of living organisms use carbonic anhydrase to enormously accelerate the H2O/CO2=H2CO3 exchange rate.
Tallbloke says:
“The biological factors shouldn’t be omitted in this debate. There is a strong correlation between fish stocks and the ~60yr oceanic cycles. This is food chain derived. If there are less fish in the warm phases of the ocean cycles then it is because there is less food for the(m) to eat. At the base of the food chain are the plankton.”
Are you serious? There is no established relationship between world fish stocks and plankton abundance in a world where all sorts of things, not the least over fishing affecting fish stocks. I can’t for the life me figure out where you got that barmy idea from. And I certainly hope you are not relying on the recent crappy, blatantly warmist Nature paper which claims a massive decline in phytoplankton levels over the last 100 years or so,. That has already been thoroughly discredited. It is astonishing it even got through peer review (says a lot about Nature).
In fact, the increasing lag between SH CO2 levels (lower) and NH CO2 levels (higher) surely indicates that in the the great Southern Ocean at least phytoplankton abundances are increasing (I posted a substantial proof of this on Stockwell’s Niche Modeling some years back). Very ferw seem to have noticed that the contribution of the NH dataset to the mean global mean surface CO2 level has slowly and monotonically increased.
Ironically, on the other hand I do agree with your contention that the curve fit does seem to best indicate a close similarity between the e-folding time and the residence time. As I see it Willis and Nick need to address this basic fact Pettersson and you raise rather than just impose their a priori assumptions about the nature of the so-called e-folding time over the recent historical period. We need to be remember just what an e-folding time is….
Hoser says: July 2, 2013 at 1:11 am
“The 14C spike is therefore a pretty good single turnover experiment, Wills. The spike is sufficiently large that it is very different from equilibrium conditions and measures exactly what we want. There is no significant backward rate of 14C returning from the large reservoir.”
And this illustrates the fallacy of the post. Yes, there was virtually no 14C in the ocean, and no backflow. But there was plenty of 12C, and apart from recent anthro, the backflow matched the downflow. Now there is an imbalance, and a nett downflow, but unrelated to the one-way value. Anyone who understands dynamic equilibruium knows this.
Well, almost unrelated. But it provides a lower bound, and that’s why tallbloke’s claim that they are comparable can’t possibly be right. The 5-10yr flux without replacement is, even with anthro burning, almost balanced by the backflow. There is no way that the nett can be comparable to the one-way. Dyson’s quote of century vs decade is typical of what is measured.
There’s a large exchange with the sea. That is dominated by seasonal flux. Every year, temperate oceans vary SST by at least 5°C. Large amounts of C are absorbed on cooling, mixed, and emitted on warming. The re-emitted molecules are different, and this is counted in the residence time, but the near-balance of the process is obligatory.
You have an atmosphere with different carbon sinks.You have a bucket with different holes in the bottom.
The atmosphere is being filled with CO2 by multiple sources at different rates.The bucket is being filled with water by multiple taps at different flow rates.
The amount of water in the bucket (V) will stabilise when the incoming flow rate (F) is the same as the outgoing flow rate. The volume is determined by the half-life (h) or residence time (r) of the water in the bucket. The relationships between F, V, h and r are:
r = V / F
h = r * ln(2)
The amount of CO2 in the atmosphere will stabilise when the incoming rate is the same as the outgoing rate. It was apparently stable, in the pre-industrial era, at 278ppm or 2173Gt. The IPCC also say the amount of CO2 entering the atmosphere from natural sources is 771Gt per year. Putting these values into the above equations give:
r = 2173/771 = 2.82 years
h = 1.95 years
If you add a pulse (P) of water to the bucket you can calculate how much is left after time (t) with the following formula:
P(t) = P * e^(-t/r)
If you add a pulse (P) of CO2 to the atmosphere you can calculate how much is left after time (t) with the following formula (according to the Berne model):
P(t) = P*( 0.14 + 0.13e^(-t/372) + 0.19e^(-t/56) + 0.25e^(-t/17) + 0.21e^(-t/4) + 0.08e^(-t/1.33) )
Curious. It looks like my bucket model of the atmosphere has failed. Never mind, a blowtorch and some pieces of metal (assuming a galvanised bucket) and I can modify the bucket so that it works.
The bucket is now divided into 6 separate sections. The percentage of the whole bucket that each section contains is: 14%, 13%, 19%, 25%, 21% and 8%. The holes in the bottom of the bucket are changed so that the 14% section does not have any holes, the 13% section has enough holes for a residence time of 372 seconds, 19% has 56s, 25% has 17s and so on. If you now add a pulse (P) of water to the bucket you can calculate how much is left after time t with the following equation:
P(t) = P*( 0.14 + 0.13e^(-t/372) + 0.19e^(-t/56) + 0.25e^(-t/17) + 0.21e^(-t/4) + 0.08e^(-t/1.33) )
What this shows is that my bucket is now a perfect physical representation of the Berne model. When it comes to pulses of CO2/water the model and my bucket share the same properties (they must since the equations are the same).
In the same way that the water from one section can not mix with the water from another section, the Berne model does not allow any CO2 mixing. Yet every single atmospheric model starts with the assumption that: “CO2 is a well mixed gas”. The bucket without sections represents an atmosphere where CO2 mixes instantly and the bucket with sections represents one with an infinite mixing time.
Of course the atmosphere with carbon sinks is different than a bucket with holes. The reason is that the holes in the bucket have a infinite capacity for letting water escape and will always be the same size, whereas a carbon sink might have a finite capacity or the absorption rate will change (or have a maximum) due to other factors such as temperature, precipitation, human activity etc.
What this all means is that calculating a half life 1.95 years (using the bucket model with well mixed water) is too simple because the half life will vary, but calculating it using the Berne model is also incorrect because it does not allow for any CO2 mixing.
Finally, if you add a mixing function to the Berne formula by calculating P(t) and then starting the calculation again with P = P(t) (this assumes it takes time t for CO2 to mix) then, with a mixing time somewhere between instant and 4 years you get a residency of between 5 and 14 years and a half life of between 7 and 20 years.
Stephen Wilde says:
July 2, 2013 at 1:38 am
The areas of highest CO2 concentration are above the sun warmed oceans under the subtropical high pressure cells and we can even see them drift to and fro latitudinally with the seasons.
Sunlight doesn’t drive CO2 out of the oceans, but temperature does. Henry’s Law shows some 16 microatm/°C increase or decrease with temperature. The difference in partial pressure between the oceans and the atmosphere is what drives CO2 out of the oceans (and into the oceans near the poles). See: http://www.pmel.noaa.gov/pubs/outstand/feel2331/exchange.shtml
I suspect that the C13/12 issue is dealt with by decomposing organic material in the oceans being a source of low C!3 CO2 just as is decomposing organic material is on land.
No, the 13C/12C ratio of the oceans (0 to 1 per mil for deep oceans, 1-5 per mil for ocean surface, is far higher than what is measured in the atmosphere (currently – 8 per mil d13C). The ocean surface is higher than the deep oceans as part of the low 13C from biomass is sinking into the deep.
Thus any substantial increase of the CO2 release by the oceans (either additional or more turnover) would increase the 13C/12C ratio in the atmosphere, but we see a firm decrease, both in the atmosphere as in the ocean surface, in lockstep with human emissions. See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
Ferdinand.
Sunlight penetrating water heats up not only water molecules but also biomass within the water. If that biomass is dead material then decomposition will be accelerated and low C13 CO2 will be given off by the decomposing biomass.
That is a separate issue to simple warming of the water molecules or warming of living material such as sponges.
There is a lot of dead and decomposing biomass floating near the surface.
Therefore it is quite possible that additional sunlight (by affecting biomass) will cause far more CO2 emissions than would be expected from the application of Henry’s Law alone.
Furthermore those ‘extra’ emissions, being from decomposing biomass rather than from the water itself would be low in C13 CO2.
The ‘lockstep’ you refer to also correlates with less clouds and more sunshine during a period of more active sun. Therefore it should be possible to check the right answer after a long enough period of quiet sun and increased global cloudiness.
tallbloke says:
July 2, 2013 at 2:44 am
You seem to be ignoring this statement in the OP:
c. The exponential character of the relaxation implies that the rate of removal of C14 has been proportional to the amount of C14.
That is true, but has nothing to do with the change in total mass: 14C is in an order of 10^-22 in mass compared to 12C and 13C. Thus the doubling of 14C didn’t change the total mass of CO2 in the atmosphere. The removal of 14C therefore is only the result of the exchange rates.
The removal of the extra CO2 from human emissions on the other hand is not a matter of exchange rate, but of changes in partial pressure in the atmosphere, as well as compared to the ocean surface as to vegetation (water in the alveoles). These decay rates are proportional to the increase of CO2 compared to the (temperature controlled) equilibrium level.
Quite different things…
TerryS says:
July 2, 2013 at 3:03 am
I fully agree that the Bern model fails on the real world, be it that it “may” be more or less right if we burn near all available oil, gas and coal… That is, there may be constraints in some of the fast sinks if we have burned 3000-5000 GtC, quite a lot more than the 370 GtC we have burned until today.
The following constraints do happen:
– some 10% of the change in the atmosphere goes into the top oceans with a decay rate of 1-3 years, but there it stops. That has to do with the carbon/buffer chemistry of the oceans. That is the Revelle factor.
– something similar happens in vegetation: while in controlled circumstances a doubling of CO2 gives an average 50% increase in growth rate, the real increase in nature is more around 15%, as other constraints are leading.
– the medium speed uptakes are in the deep oceans and more permanent storage by vegetation. These have half lives of ~40 years. The deep oceans are far from saturated for the moment, thus there is no current limit in uptake, only a limit in exchange speed, but it may come in the (far) future. On the other side, there is absolutely no limit in permanent storage of carbon in vegetation, which still can be seen in the coal layers we use up to today.
As these are the main sinks today and into the far future, they are the leading sinks and the slower sinks play no role at all in the sink rate: the fastest would give the real rate, the slowest only ad a little to the uptake. That is what is seen in reality: there is no decrease in sink ratio (the “airborne fraction”) over time, to the contrary.
Thus, indeed forget the Bern model for the next few hundred years (especially the “constant” term, which is not applicable for relative small releases).
dp says, about atmospheric CO2: “… Or pulled into the CO2-scarce water that is being removed from aquifers …”
Water in all aquifers I am familiar with is super-saturated with CO2. That is why it is possible to reduce water hardness by boiling it, driving the CO2 off and letting carbonates precipitate. The net effect of groundwater use should be an excess of CO2 in the atmosphere, whether the water is boiled or not.
@Willis Eschenbach
The assumption behind tracer experiments and I have done many in my time, is that the concentration of tracer is infinesimal compared to the pool, which is clearly the case with bomb induced c14. In this case, provided c14 is handled by the biosphere in a similar manner, the decay curve gives the pool turnover. This has been validated in thousands of experiments and is the be basis for kinetic experiments in metabolism This may be corrected for fluctuating pool size, as has been done here.
I would have to say that your fundamental assumptions are not correct.
Willis Eschenbach says:
July 2, 2013 at 12:05 am
Ian W says:
July 1, 2013 at 10:42 pm
It is rare to see Willis and Nick Stokes making the same incorrect argument.
Their erroneous assumption being that the capacity of the natural carbon dioxide sink is static and can only reabsorb carbon dioxide at a particular rate. Yet we have (as dp says:July 1, 2013 at 9:35 pm,) a satellite identified increase in plant life worldwide and a greening of the deserts. Nature is hungry for more carbon dioxide it will be absorbed at an increasing rate with increasing atmospheric abundance.
Now, Roger Tallbloke claims above that I have “never, ever,” addressed this issue … Roger, either point out where I declined to address this issue, or go away. Your vague uncited and unsubstantiated attacks grow tiresome.
In any case, Ian, you say that I’m assuming that “the natural carbon dioxide sink is static”. Please quote my words where I’ve made that assumption, and what kind of error you think it produces. And if you can’t find anyplace I made that claim, you can accompany tallbloke out the door for all I care.
Guys, the kind of unsubstantiated mudslinging that you are engaging in is reprehensible. If you disagree with something I say, at least have the huevos to quote what it is that has you upset.
Because I certainly don’t recall making any such assumptions, or avoiding this strange issue in the past … why and where would I have claimed that the carbon sinks are static? Nothing on this planet is static.
w.
Willis, not a straw man… A hidden assumption is not ‘quotable’ . The only way you can come up with a fixed period of time or in your words “the time constant for the exponential decay of a single pulse of CO2 injected into the atmosphere”. Is to have a fixed rate of absorption of carbon dioxide by the climate system. So your reasoning goes the man is really thirsty and put a large glass of cold water in front of him and he can drink that in 10 seconds (residence time) – if a ‘pulse of 10 glasses is put in front of him it will take 10 times as long (the pulse half life) for that water to be drunk. You are making the implicit assumption that the other name a large number of thirsty men will not also swarm the bar and drink the water and regardless of the number of glasses the water in them is drunk in 10 seconds. The free water draws a crowd and the original men are still thirsty so all of them (an unknown and growing number) will drink water in 10 seconds. .
What Roger and I are saying is that the natural biome is ‘thirsty for carbon dioxide. Plants can consume carbon dioxide at rates far faster than humankind can produce it and as they receive more carbon dioxide the number of plants increases at an unknown rate. Rather the implicit assumption from you and Nick Stokes that there is a ‘constant’ that leads to a pulse half life (Nick even tries to provide a fixed constant ‘weight’ for the biome.) . .
Hope that helps 😉
TerryS says: July 2, 2013 at 3:03 am
I’ll take up this math, because it illustrates the fallacy. I’m OK down to (but not including)
P(t) = P * e^(-t/r)
But that is wrong in the case of CO2. It’s basically a differential equation:
-dP/dt=P/r.
And -dP/dt is the outflow. It is just the first equation, saying that r=d(Vol)/d(F), or r*dF=dV
That’s reasonable for holes in a bucket; leakage proportional to depth. But it assumes the taps have a fixed flow.
In the air/ocean situation, that just isn’t true. The tap is just the reverse diffusive pathway, and its flux I is also proportional to V (amt of CO2) by Henry’s Law. And you can do the same residence time calc in terms of inflow:
I=V/r.
So dP/dt = dI/dt-dF/dt = V/r-V/r = 0
This is telling you that you just can’t get it this way. The two-way reaction kinetics don’t tell you the pulse decay rate. As FE says, they are different things.
Oops
dP/dt = dI/dt-dF/dt =1/r dV/dt – 1/r dV/dt = 0
cohenite says:
July 2, 2013 at 1:47 am
“But the nett flux is into the sea, not out of it. And not into the land biosphere, where the total mass of C, at about 700 Gt, is not that much more than the 400Gt we’ve burnt. ”
Key points; are they assumed or do you have non-modelled data?
“A bomb deposition of carbon decays very fast.
The slow pollution decays very slow.”
Interesting point Alex; what physical mechanism would do that?
———————
Don’t know whether you a familiar with linear differential equations.
There are eigenmodes.
Each eigenmode has its own decay time.
IPCC calls these eigenmodes in weird terms “partitionings”. Whatever they mean.
http://unfccc.int/resource/brazil/carbon.html
The physics is straightforward.
You have different CO2 uptake channels and each channel has its own equilibration time.
Good in theory.
In practice, one has to measure these times.
Certainly, I don’t bet a penny IPCC does it right.
They also never measure. They “model”.
tallbloke says:
July 2, 2013 at 2:44 am
You seem to be ignoring this statement in the OP:
c. The exponential character of the relaxation implies that the rate of removal of C14 has been proportional to the amount of C14. This means that the observed 95% of the relaxation process have been governed by the atmospheric concentration of C14-carbon dioxide according to the law of mass action, without any detectable contributions from slow oceanic events.
—
No, this is still connected to the magnitude of the leakage. And, of course I mean the total C12 + C14 leakage. The exponential relaxation the author describes here is the amount of C14 atoms compared with the C12 atoms. You will have an exponential decrease in the C14/C12 ratio even if the leakage is constant.
In reply to:
Ferdinand Engelbeen says:
July 2, 2013 at 2:32 am
William: The residence time of CO2 or C14, and the “e-folding time” of a pulse of CO2 emitted to the atmosphere are different. A C14 pulse in the atmosphere cannot be used to determine the “e-folding time” of a pulse of CO2.
There does however appear to be a puzzle to solve. Could someone please summarize the anomalies and observations? I am still think about Salby’s presentation.
What is the explanation for the missing carbon sinks’ evolution with anthropogenic CO2 emission?
What are your thoughts on ‘Temperature’ effects on the atmospheric carbon dioxide level?
It should be noted that the warmists are suddenly appealing to heat hiding in the deep ocean which requires there to be significantly more mixing of deep ocean water and ocean surface water.
As noted in comment there is a seldom discussed source of ‘fossil’ fuel like C12/C13 in the deep ocean that is released as CH4. The upper ocean is saturated with CH4 which indicates that is a continual excess source of CH4 that is released.
The deep earth’s CH4 emission rate is not controlled by surface planetary temperature, however, what is affecting surface planetary temperature (changes to the solar magnetic cycle) may also be affecting the rate of CH4 release.
There are a host of anomalies concerning the geological evolution of atmospheric CO2 level.
Comments:
1. Source of atmosphere and source of ‘fossil’ fuel. As I have stated before is a set of observations and analysis to support the assertion that there is a large source of CH4 that is released from the deep earth. There are two theories to explain how the planet got light volatile elements after the big splat removed them the majority of the volatile elements from the mantel: 1) the later veneer theory and 2) the deep earth theory. The CH4 that is released from the deep earth is low in C13, similar to ‘fossil’ fuel or lower. I place quotations around the word ‘fossil’ as people need to read Thomas Gold’s Deep Earth Hot Biosphere: The Myth of Fossil Fuels so we can have an informed discussion concerning the evolution of the planet’s atmosphere and the explanation as to why 70% of the surface of the planet is covered with H20. The deep earth CH4 that is released disassociates high in the atmosphere and forms CO2 and H20. Plants and reactions in the ocean remove the CO2 which explains the massive deposits of carbon in the sediments.
2. There is no explanation for the reduction in CO2 during the glacial phase. The increased CO2 dissolved in the ocean due to colder temperatures is more than offset by the reduction in the size and efficiency of the biosphere due to the increase in size of the ice sheets and due to reduction in precipitation. Large portions of the rainforest (Amazon) is converted to savanna during the cold dry glacial phase.
3. There is no explanation for why CO2 levels gradually reduced when ice sheets cover the planet. On geological time periods the ice sheets first cover the planet and then gradually atmospheric CO2 is reduced.
Another fundamental error in the article:
During the last two decades, contributions from thermal out-gassing have been almost 40% larger than those from anthropogenic emissions.
That is based on a model, which is problematic. While the degassing in the warm pool is increased by warmer temperatures, and the uptake is reduced, in the model, there is no room left for the feedback from the increase of CO2 in the atmosphere.
The increase in temperature increases the pCO2 of the oceans, leading to an increase of pCO2 difference with the atmosphere in the warm pool and a decrease in pCO2 difference with the atmosphere at the cold sink places. As the flux rate is directly proportional to the pCO2 difference (at constant average wind speed), the influx from the oceans increases and the outflux to the oceans decreases, leading to an increase of CO2 in the atmosphere.
The pCO2 of the atmosphere then increases until the pCO2 difference between atmosphere and warm/cold pool is restored and hence the resp. fluxes. That is for seawater at about 16 ppmv/°C change in temperature (Henry’s Law at work).
Paper 3 and Fig. 3 don’t take this feedback into account and thus are fundamentally wrong.
Re: Nick
The Berne model (not me) uses the following equation for the decay rate of a pulse of CO2:
P(t) = P*( 0.14 + 0.13e^(-t/372) + 0.19e^(-t/56) + 0.25e^(-t/17) + 0.21e^(-t/4) + 0.08e^(-t/1.33) )
Look at the equation closely. All they have done is separate the pulse P into 6 parts and applied the formula P(t) = P * e^(-t/r) to each part with different fractions of P and different values of r (infinity for the 0.14 fraction).
This equation can be exactly replicated with the bucket divided into six parts. Just as the sectioned bucket has no water mixing, the Berne model has no CO2 mixing. Without CO2 mixing the model is wrong.
Whatever math one is using, it better calculate that the rate by which Oceans, Plants and Soils (the natural sinks) are absorbing Carbon out of the atmosphere is increasing. And it will continue increasing until CO2 levels stabilize.
The natural absorption rate is equivalent to 2.0% per year of the excess Carbon in the atmosphere above the equilibrium level (which is about 275 ppm (CO2)).
http://s21.postimg.org/ab6uih3wn/Nat_Absorp_Rate_CO2_1750_2012.png
Thanks to all who have contributed to this spirited debate : I’m now better informed on the different issues involved, The posts have highlighted just how many factors have to be considered.
RCSaumarez says:
July 2, 2013 at 3:59 am
The assumption behind tracer experiments and I have done many in my time, is that the concentration of tracer is infinesimal compared to the pool, which is clearly the case with bomb induced c14. In this case, provided c14 is handled by the biosphere in a similar manner, the decay curve gives the pool turnover.
14C is handled in a similar matter as 12C or 13C for temperature dependent processes: the bulk of the exchanges are seasonal where temperature changes induce huge CO2 exchanges between air and vegetation and back and countercurrent between air and oceans and back. That is the main cause of the huge turnover and decay of 14C.
The removal of an excess amount of CO2 is hardly temperature dependent, it is mainly differential pressure dependent. The CO2 partial pressure difference between atmosphere and oceans ranges from +350 microatm in the warm pool to -250 microatm in the cold NE Atlantic waters. Temperature has added some 16 microatm to the ocean waters side since the LIA, humans (or any other source for that matter) has added 100 microatm (~100 ppmv) to the atmosphere…
Thus the decay rate of an excess amount of CO2 (whatever the source) is near independent of the residence time and thus of the decay rate of 14C.
TerryS says: July 2, 2013 at 5:16 am
Presumably the Bern model’s justification is empirical. It’s really just a fit to a (claimed) observed response function. But you are using a mass balance argument to say that the decay is exp(-t/r). Not an observed time constant, but derived theoretically from the bucket equilibrium analogy.
And I’m saying that’s unsound, because the influx and outflow are of the same kind – in the case of ocean, just diffusive pathways. So fixed flux taps and V-varying holes won’t work.
It’s not the claim of exponential decay that bothers me so much, it’s the claim that the time constant is r. The argument for that is wrong. If you disagree, then you should spell it out.