UPDATED – see below
Monckton provides these slides for discussion along with commentary related to his recent post on CO2 residence time – Anthony
There is about one molecule of 13C in every 100 molecules of CO2, the great majority being 12C. As CO2 concentration increases, the fraction of 13C in the atmosphere decreases – the alleged smoking gun, fingerprint or signature of anthropogenic emission: for the CO2 added by anthropogenic emissions is leaner in 13C than the atmosphere.
However, anthropogenic CO2 emissions of order 5 Gte yr–1 are two orders of magnitude smaller than natural sources and sinks of order 150 5 Gte yr–1. If some of the natural sources are also leaner in CO2 than the atmosphere, as many are, all bets are off. The decline in atmospheric CO2 may not be of anthropogenic origin after all. In truth, only one component in the CO2 budget is known with any certainty: human emission.
If the natural sources and sinks that represent 96% of the annual CO2 budget change, we do not have the observational capacity to know. However, we do not care, because what is relevant is net emission from all sources and sinks, natural as well as anthropogenic. Net emission is the sum of all sources of CO2 over a given period minus the sum of all CO2 sinks over that period, and is proportional to the growth rate in atmospheric CO2 over the period. The net emission rate controls how quickly global CO2 concentration increases.
CO2 is emitted and absorbed at the surface. In the atmosphere it is inert. It is thus well mixed, but recent observations have shown small variations in concentration, greatest in the unindustrial tropics. Since the variations in CO2 concentration are small, a record from any station will be a good guide to global CO2 concentration. The longest record is from Mauna Loa, dating back to March 1958.
The annual net emission or CO2 increment, a small residual between emissions and absorptions from all sources which averages 1.5 µatm, varies with emission and absorption, sometimes rising >100% against the mean trend, sometimes falling close to zero. Variation in human emission, at only 1 or 2% a year, is thus uncorrelated with changes in net emission, which are independent of it.
Though anthropogenic emissions increase monotonically, natural variations caused by Pinatubo (cooling) and the great el Niño (warming) are visibly stochastic. Annual changes in net CO2 emission (green, above) track surface conditions (blue: temperature and soil moisture together) with a correlation of 0.93 (0.8 for temperature alone), but surface conditions are anti-correlated with δ13C (red: below).
The circulation-dependent naturally-caused component in atmospheric CO2 concentration (blue above), derived solely from temperature and soil moisture changes, coincides with the total CO2 concentration (green). Also, the naturally-caused component in δ13C coincides with observed δ13C (below).
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ADDED (the original MS-Word document sent by Monckton was truncated)
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The naturally-caused component in CO2 (above: satellite temperature record in blue, CRU surface record in gray), here dependent solely on temperature, tracks not only measured but also ice-proxy concentration, though there is a ~10 µatm discrepancy in the ice-proxy era. In the models, projected temperature change (below: blue) responds near-linearly to CO2 concentration change (green).
In the real world, however, there is a poor correlation between stochastically-varying temperature change (above: blue) and monotonically-increasing CO2 concentration change (green). However, the CO2 concentration response to the time-integral of temperature (below: blue dotted line) very closely tracks the measured changes in CO2 concentration, suggesting the possibility that the former may cause the latter.
Summary
Man’s CO2 emissions are two orders of magnitude less than the natural sources and sinks of CO2. Our emissions are not the main driver of temperature change. It is the other way about.
Professor Salby’s opponents say net annual CO2 growth now at ~2 μatm yr–1 is about half of manmade emissions that should have added 4 μatm yr–1 to the air, so that natural sinks must be outweighing natural sources at present, albeit only by 2 μatm yr–1, or little more than 1% of the 150 μatm yr–1 natural CO2 exchanges in the system.
However, Fourier analysis over all sufficiently data-resolved timescales ≥2 years shows that the large variability in the annual net CO2 emission from all sources is heavily dependent upon the time-integral of absolute global mean surface temperature. CO2 concentration change is largely a consequence, not a cause, of natural temperature change.
The sharp Pinatubo-driven cooling of 1991-2 and the sharp Great-el-Nino-driven warming of 1997-8, just six years later, demonstrate the large temperature-dependence of the highly-variable annual increments in CO2 concentration. This stochastic variability is uncorrelated with the near-monotonic increase in anthropogenic CO2 emissions. Absence of correlation necessarily implies absence of causation.
Though correlation between anthropogenic emissions and annual variability in net emissions from all sources is poor, there is a close and inferentially causative correlation between variable surface conditions (chiefly temperature, with a small contribution from soil moisture) and variability in net annual CO2 emission.
Given the substantial variability of net emission and of surface temperature, the small fraction of total annual CO2 exchanges represented by that net emission, and the demonstration that on all relevant timescales the time-integral of temperature change determines CO2 concentration change to a high correlation, a continuing stasis or even a naturally-occurring fall in global mean surface temperature may yet cause net emission to be replaced by net uptake, so that CO2 concentration could cease to increase and might even decline notwithstanding our continuing emissions.
Natural temperature change and variability in soil moisture, not anthropogenic emission, is the chief driver of changes in CO2 concentration. These changes may act as a feedback contributing some warming but are not its principal cause.
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Bart says:
November 25, 2013 at 12:00 pm
First, do you then acknowledge that your comment at November 25, 2013 at 11:22 am is not at all as categorical as you allege? That if CO2 rich waters are upwelling as I hypothesize, then that would lead to just such a temperature dependency as we observe?
– a finite increase in temperature gives a finite increase of CO2 in the atmosphere.
– a finite increase in upwelling (either amount or concentration) gives a finite increase of CO2 in the atmosphere.
– a combination of both gives a finite increase of CO2 in the atmosphere.
– a linear increase in temperature gives a linear increase of CO2 in the atmosphere.
– a linear increase in upwelling gives a linear increase of CO2 in the atmosphere.
– a combination of both gives a slightly non-linear increase of CO2 in the atmosphere.
Only in the latter case can the linear increase in temperature mimic the slope in trend of the derivative of the CO2 trend. But there is not the slightest sign that the upwelling (infact the througput) increased over time, to the contrary…
Ferdinand Engelbeen says:
November 25, 2013 at 1:18 pm
“- a finite increase in upwelling (either amount or concentration) gives a finite increase of CO2 in the atmosphere.”
If by that, you mean a finite pulse in upwelling, then I agree. But, a sustained increase in upwelling concentration above that of current surface waters will gradually diffuse throughout the surface oceans, and continuously increase their concentration, which thereby continuously outgases to the atmosphere.
“But there is not the slightest sign that the upwelling (infact the througput) increased over time, to the contrary…”
In fact, we do not have direct measurements of the rate of inflow of CO2 to the surface waters, so no way of dismissing the hypothesis.
This is, in fact, precisely what the observed temperature dependency of the rate of change of CO2 indicates to be likely. And, I only qualify it as “likely” because there could be other temperature dependent sources than the oceans. But, the oceans appear to be the most probable source.
It seems to me that allowing more sunlight into the surface waters beneath the subtropical high pressure cells could drive out CO2 by heating individual surface or near surface molecules directly but without necessarily resulting in a significant rise in averaged global atmospheric temperature.
Also, did Ferdinand produce any evidence (rather than supposition) that the CO2 emissions from the sun warmed oceans are actually richer in C13 than C12 despite the undoubted presence of substantial biological activity in surface waters ?
Greg Goodman says:
November 25, 2013 at 12:56 pm
Some more indications about ocean temperature and dryness of the Amazon forest:
http://wattsupwiththat.com/2011/11/11/ocean-temperatures-can-predict-amazon-fire-season-severity/
Sometimes it may help if you read the papers I have already referenced before… In:
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf
From the abstract:
Interannual variability calculated from these data shows a strong land carbon source associated with the 1997–1998 El Niño event, supporting many previous studies indicating that high atmospheric growth rates observed during most El Niño events reflect diminished land uptake.
And in the text, at point [70]:
This work thus supports many previous studies linking rapid atmospheric CO2 growth rates with diminished land carbon uptake during El Niño events [e.g., Keeling et al., 1989; Clark et al., 2003; Nemani et al., 2003; Schaefer et al., 2002; Reichenau and Esser, 2003]. The primary mechanism is now thought to be increased aridity and biomass burning in tropical areas during El Niño events [Langenfelds et al., 2002; van der Werf et al., 2004].
It would lead to a 50y lag in response to a steady increase in driver. It may be interesting to see how well that plays out in relation to changes in both temp and atm CO2.
I have no idea how to derive a lag from a response time, so you may teach me how to do that.
I am learning more about integrals, derivatives and that kind of stuff now in last years than I have used in the past 50 years…
Anyway, if you look at the increase rate in the atmosphere vs. human emissions, you can see a lag of 20 years which still is growing:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_co2_acc_1900_2011.jpg
With not such a nice connection for the temperature trends…
Bart says:
November 25, 2013 at 1:42 pm
If by that, you mean a finite pulse in upwelling, then I agree. But, a sustained increase in upwelling concentration above that of current surface waters will gradually diffuse throughout the surface oceans, and continuously increase their concentration, which thereby continuously outgases to the atmosphere.
For a fixed temperature, a fixed, sustained increase in upwelling will give a fixed, sustained increase of CO2 in the atmosphere, no matter if that happens directly at the upwelling places or diffuse over a larger area. For a fixed temperature an increase in concentration gives a near-linear increase in pCO2, thus a fixed increase in outflux, which leads to a fixed increase of CO2 in the atmosphere:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/upwelling_incr.jpg
Ferdinand Engelbeen: “I have no idea how to derive a lag from a response time, so you may teach me how to do that.”
Pardon me for being an officious intermeddler; I’m sure Mr. Goodman is more than capable of responding, and, besides, I’m not entirely positive that I understand the question. Just in case it is of any interest at all, though, I just set forth the response to a steady increase in connection with Prof. Pettersson’s’ model at http://wattsupwiththat.com/2013/11/21/on-co2-residence-times-the-chicken-or-the-egg/#comment-1484013.
Stephen Wilde says:
November 25, 2013 at 2:03 pm
Also, did Ferdinand produce any evidence (rather than supposition) that the CO2 emissions from the sun warmed oceans are actually richer in C13 than C12 despite the undoubted presence of substantial biological activity in surface waters ?
Stephen, I don’t know what you exactly mean, but have a look at:
http://www.sciencemag.org/content/298/5602/2374/F1.large.jpg
That is the graph of the measurement series at Bermuda (BATS) where peak temperature in summer gives maximum pCO2 (thus most of the releases) and minimum DIC (thus most of the releases and most of the bioactivity) and maximum δ13C (thus maximum bioactivity)
The scale of δ13C is inverted, which is rather confusing…
Even with the increased δ13C levels, still most of what is emitted is 12CO2, just over 1% is 13CO2…
Ferdinand Engelbeen,
It has been little over 3 years since you posted at WUWT your 4 part essay entitled ‘Engelbeen on why he thinks the CO2 increase is man made’. Your part 4 essay was posted September 2010.
I suggest you update your position.
I suggest in any update that you differentiate your position from the IPCC’s AR5 assessement of science on the carbon cycle. Skeptics have assessed there is systematic institutional bias wrt IPCC processes, so clarity wrt your position would be helpful.
Also, another reason for you to update is the level of skepticism in climate science has surged in the past three years. Arguments evolved that can be addressed, Salby’s being just one. Note: Salby came to public attention more than a half year after your WUWT essay.
Once again, I would like to sincerely compliment you on the level of your civility and professional bearing in WUWT commentary. I find myself in disagreement with your fundamental overall logic, but I do not disagree with your intent toward factual focus nor with your seriousness toward reasoning and science.
John
Ferdinand Engelbeen says:
November 25, 2013 at 2:30 pm
“For a fixed temperature, a fixed, sustained increase in upwelling will give a fixed, sustained increase of CO2 in the atmosphere…”
A sustained rise in the rate of incoming CO2 will continuously increase the pCO2 of the surface waters, until such a time as the pCO2 of the incoming waters matches the pCO2 of the surface waters, i.e., until the entire surface ocean is essentially replaced. That will continuously increase the pCO2 of the atmosphere.
Ferdinand Engelbeen says:
November 25, 2013 at 2:57 pm
How representative is Bermuda? I would think the Pacific Ocean off of South America would be the ideal location to perform measurements.
Greg Goodman asked me “Sorry, I must have missed a trick. Which part of your “A-CO2″ account shows 8ppmn/K/year relationship between CO2 and SST ?”
Sorry for the delay in my answer. The relationship is as much as 4-5 ppm / K over some time periods. That is from the “hard evidence” plot linked above. Not per year since the relationship doesn’t hold each year and is not cumulative. It held in 1997 with a bit over 2ppm CO2 against a temperature rise but in 1998 we saw a bit under 3 ppm gain in CO2 against a net drop in temperature. However for the most part there is a couple ppm CO2 response to temperature changes. Also there is a possible lag as you pointed out. The lag is not evident in the “hard evidence” link above but there is 12 month smoothing of the CO2 that helps show the correlation.
My specific answer is that the steady CO2 rise is completely manmade but there is a natural variation in that rise dependent on temperature, mostly temperature and weather in specific locations but also shows up in the global average temperature. IOW the net uptake by oceans is modulated by temperature. That is my explanation of the “hard evidence” correlation.
Bart (November 25, 2013 at 9:09 am) “You are just not getting it. You cannot get a sensitivity in ppmv/K when you have one in ppmv/K/unit-of-time. You do not get a finite change for a finite change in temperature.”
Both measurements are per unit of time. In all my posts above I refer to ppm changes per year against degrees K changes per year. There is no other measurement possible for the latter when considering changes in temperature. The resultant units are therefore ppm per degree.
Speaking of the oceanic CO2 emissions Ferdinand said:
“Even with the increased δ13C levels, still most of what is emitted is 12CO2, just over 1% is 13CO2”
Then consider that Christopher in his post said this:
“As CO2 concentration increases, the fraction of 13C in the atmosphere decreases – the alleged smoking gun, fingerprint or signature of anthropogenic emission: for the CO2 added by anthropogenic emissions is leaner in 13C than the atmosphere.
However, anthropogenic CO2 emissions of order 5 Gte yr–1 are two orders of magnitude smaller than natural sources and sinks of order 150 5 Gte yr–1. If some of the natural sources are also leaner in CO2 (I think Christopher meant C13) than the atmosphere, as many are, all bets are off. The decline in atmospheric CO2 may not be of anthropogenic origin after all. ”
Doesn’t Ferdinand’s comment confirm that oceanic emissions are leaner in C13 than the emissions from the land based biosphere so increasing oceanic emissions on their own would dilute 13C in the atmosphere would it not ?
The proportion of atmospheric C13 would be reduced whenever ocean emissions increased relative to the land based biosphere emissions and would be increased whenever ocean emissions decreased relative to the land based biosphere emissions.
Perhaps the point eric1skeptic is making would be easier to see if we rearranged Bart’s equation.
(dCO2/dt)=0.19T + 0.14
where T is the temperature anomaly
so (dCO2/dt)-0.14=0.19T
and
(d/dt)(CO2-0.14t)=0.19T
i.e a linear term is subtracted from the CO2 series.
Now the value 0.14 is almost exactly the trend (in ppm/month) in CO2 variation for the time period (1979-present) used.
So Bart’s equation in words reads,
The derivative of the detrended CO2 variation is proportional to the temperature anomaly. This is interesting. The fluctuations away from the trend are proportional to temperature. However it does not show anything about the trend’s dependence. Whether the longer term trend in the CO2 concentration follows T, precedes T or has no connection at all to T, is not deducible from that equation.
eric1skeptic says:
November 25, 2013 at 3:55 pm
I’m sorry, no. I have tried to explain it to you, but you refuse to understand it.
It is cumulative. Once you have a temperature offset, the accumulation of CO2 continues, whether the temperature changes again or not.
You can see it right now. Global temperatures have stagnated, and so has the rate of change of CO2. Emissions, meanwhile, keep accelerating faster and faster.
The rate of change did not fall to zero, as you would have it. It settled out in lock step with the temperature pause.
jimmi_the_dalek says:
November 25, 2013 at 4:27 pm
Ugh. Not this silliness again.
No, no, no, a thousand times NOOOOOO!!!!
I am not arguing on the basis of the linear trend in total CO2. I am arguing on the basis of the variability, and the quadratic factor in total CO2, i.e., the variability and trend in the rate of change of CO2. They match the trend in temperature with incredibly high fidelity.
Yes, the linear trend is not dispositive. It. Does. Not. Matter. There is other information available here which pins attribution on the temperature relationship, and not on human inputs.
I keep telling you this, and you keep making the same non-point over and over again regardless.
jimmi_the_dalek says:
November 25, 2013 at 4:27 pm
Let me make this clearer:
I am not arguing on the basis of the linear trend in total CO2. I am arguing on the basis of the variability, and the quadratic factor in total CO2, i.e., the variability and trend in the rate of change of CO2. They both match the variability and trend in temperature with incredibly high fidelity.
You are worried about the trend in total CO2, which is the bias offset in the rate of change of CO2. I do not care about that. My argument does not hinge on it. I care about the trend in the rate of change of CO2, which is NOT responsible for the trend in total CO2, but for the quadratic component.
Emissions also have a trend in the rate of change, which would induce a quadratic component in accumulated emissions. There is no room for it in total CO2. The trend in the rate of change is already accounted for by the temperature relationship. Which is to say, the quadratic component in total CO2 is already accounted for by the temperature relationship.
THINK!!! And, address the actual argument, and not a straw man.
Stephen Wilde says:
November 25, 2013 at 4:12 pm
“Doesn’t Ferdinand’s comment confirm that oceanic emissions are leaner in C13 than the emissions from the land based biosphere so increasing oceanic emissions on their own would dilute 13C in the atmosphere would it not ?”
Hmm, good catch. Maybe you stumbled over your wording, Ferdinand?
“I am not arguing on the basis of the linear trend in total CO2. I am arguing on the basis of the variability, and the quadratic factor in total CO2, i.e., the variability and trend in the rate of change of CO2. They both match the variability and trend in temperature with incredibly high fidelity.
Yes, they do. So what?
You are banging on (and on) about the tiny fluctuations represented by the deviations from the trend, while ignoring the trend. Those fluctuations sum to (to high fidelity as you put it), zero. Why on earth do you think they matter?
Why don’t you try thinking?
“Emissions also have a trend in the rate of change, which would induce a quadratic component in accumulated emissions. There is no room for it in total CO2.
So you say – most people would say it is already there, and all you are saying is that you cannot add it twice.
jimmi_the_dalek says:
November 25, 2013 at 5:40 pm
“You are banging on (and on) about the tiny fluctuations represented by the deviations from the trend, while ignoring the trend.”
You keep ignoring the trend in dCO2/dt, which is matched by the trend in temperatures when you match the variability.
The rate of emissions also has a trend. There is no room for it. The trend in mean temperature anomaly already accounts for the trend in dCO2/dt, which is the rate of change of CO2.
The bias offset is then just the obvious baseline to which the temperature anomalies should be referenced. There is nothing underhanded about doing so. The baseline for mean temperature anomaly in each data set is just an arbitrarily chosen zero reference.
“So you say – most people would say it is already there, and all you are saying is that you cannot add it twice.”
Yes. You cannot add it from the emissions because it is already added in by the temperature relationship when you match the variational components.
jimmi_the_dalek says:
November 25, 2013 at 5:40 pm
“Why on earth do you think they matter?”
Because such are the clues which tell you what is truly happening. They are the distinguishing characteristics by which you can separate suspects from culprits. Like fingerprints. Why would anyone care about some tiny ridges on a person’s finger? Because when you match them, then you’ve found the perpetrator of the crime.
“The bias offset is then just the obvious baseline to which the temperature anomalies should be referenced.
And so it is just a coincidence that it just happens to be the value which detrends the CO2 series?
If you actually do the integral of,
d(co2)/dt = 0.19T + 0.14
from 1979 to the present (i.e. the range of the data you used) then only 1 ppm of the change in CO2 comes from the integral of 0.19T. Do you not think that this means that claiming that these fluctuations are significant is the straw man here?
I might add that the equation is hopeless at hindcasting – it would have predicted that CO2 fell in the 1960’s
“Because such are the clues which tell you what is truly happening.”
Fine, you think that something that is zero within experimental error is significant. I don’t. I will leave this to someone else to continue.
jimmi_the_dalek says:
November 25, 2013 at 6:23 pm
“Do you not think that this means that claiming that these fluctuations are significant is the straw man here?”
Yes. It is the converse, that the large trend tells you something, which is incorrect. A trend is very vanilla. Very commonplace. It is almost impossible to uniquely identify it with anything.
“I might add that the equation is hopeless at hindcasting – it would have predicted that CO2 fell in the 1960′s”
Apparently not. Yes, this is a different time series, with different fit coefficients, mainly in the arbitrary offset bias. But, the two datasets have different baselines to begin with. Which just goes to show that the baseline is arbitrary to begin with.
“Fine, you think that something that is zero within experimental error is significant.”
Who determines the experimental error? How is that error affected by all the filtering to get the end product? E.g., independent errors are attenuated by 1/sqrt(N) when you have an N-point average.
This appears to be an attempt to avoid accepting that this is an incredibly good fit to everything which is going on.
Bart said:
““Doesn’t Ferdinand’s comment confirm that oceanic emissions are leaner in C13 than the emissions from the land based biosphere so increasing oceanic emissions on their own would dilute 13C in the atmosphere would it not ?”
Hmm, good catch. Maybe you stumbled over your wording, Ferdinand?”
I don’t think he did but would appreciate confirmation.
Vegetation absorbs C12 preferentially and releases C13 preferentially.
Oceans appear to release C12 preferentially.
Altering the relative speed and sizes of the land based vegetation and oceanic sources appears to naturally deplete C13 when the oceans are warm and naturally increase C13 when the oceans are colder. If the rate of oceanic release of C12 runs ahead of the rate of vegetative release of C13 then the proportion of C13 will be diluted as actually observed with no need to blame our emissions.
Furthermore our fossil fuels generate C12 preferentially and so would be favoured for local and regional take up from energised land based vegetative sinks. CO2 being heavier than air would give plants a good chance of grabbing it before it mixed upward from convective uplift.
In reply to:
Ferdinand Engelbeen says:
November 25, 2013 at 4:27 am
William Astley says:
November 25, 2013 at 1:17 am
You are ignoring the fact as pointed out by Salby that the recent CO2 changes in the atmosphere correlate with the integral of ocean temperature rather than change in anthropogenic CO2 emissions.
William, I am not the least interested in the origin of CH4, because there is no correlation between ocean temperature (integrated or not) and recent emissions of CH4 as can be seen as levels in the atmosphere. Neither are the current levels comparable with historical levels. By coincidence (?) sharply increasing when humans started to use it. Thus in my opinion, humans are the cause of the increase.
William:
I repeat again: “You are ignoring the fact as pointed out by Salby that the recent CO2 changes in the atmosphere correlate with the integral of ocean temperature rather than change in anthropogenic CO2 emissions.”
William: The above statement does not does include the word ‘CH4’. I am not talking about CH4. Are you trying to change the subject?
Salby’s points out a fact that the recent CO2 changes in the atmosphere correlate with the integral of the ocean temperature rather than the change in anthropogenic CO2 emissions. As anthropogenic emissions are increasing and ocean temperature in the last 17 has not increased that means a large percentage of the anthropogenic CO2 must be absorbed in the biosphere which does not makes sense based on the IPCC model (i.e. The IPCC model is incorrect.) That observation and the bomb test C14 changes in the atmosphere indicate that IPCC’s Bern model (which is used to model how long anthropogenic CO2 will remain in the atmosphere before mixing) is not correct.
The Bern model has three relaxation times: 1.2, 19, and 173 years; to model the three CO2 sinks; land, surface ocean, and deep ocean.
As I noted if there is significant mixing of the deep ocean with surface ocean water then a greater portion of the anthropogenic CO2 is mixed with the deep ocean. As the carbon in the deep ocean is more than 50 times greater than the carbon in the atmosphere the effects of the anthropogenic CO2 emissions is diluted if there is significant mixing of the surface ocean water with the deep ocean water. The heat hiding in the deep ocean requires there to be significant mixing of the surface ocean water with the deep ocean water. The warmists cannot have it both ways. The warmists hypothesis that heat is hiding in the ocean supports the assertion that the Bern equation is incorrect.
http://wattsupwiththat.com/2013/07/01/the-bombtest-curve-and-its-implications-for-atmospheric-carbon-dioxide-residency-time/
The Bern model assumes there is not significant mixing of the surface ocean water with the deep ocean water which is not correct, as can be seen by figure 2 in this paper. The physical reason the C14 created in the atomic bomb tests of the 1960s drops to very, very, low levels is due to the fact that there is significant mixing of the surface ocean with the deep ocean water.
http://www.false-alarm.net/wp-content/uploads/2013/06/paper1.pdf
Figure 2. The bombtest curve, compared with response functions proposed to
account for the relaxation of an excess of atmospheric carbon dioxide
As the paper notes below roughly 50% of the recent increase in atmospheric CO2 is due to the increase in the ocean surface temperature, not due to anthropogenic CO2 emissions.
http://www.false-alarm.net/wp-content/uploads/2013/06/paper2.pdf