UPDATED: Roy Spencer on how Oceans are Driving CO2

NOTE: Earlier today I posted a paper from Joe D’Aleo on how he has found strong correlations between the oceans multidecadal oscillations, PDO and AMO, and surface temperature, followed by finding no strong correlation between CO2 and surface temperatures. See that article here:

Warming Trend: PDO And Solar Correlate Better Than CO2

Now within hours of that, Roy Spencer of the National Space Science and Technology Center at University of Alabama, Huntsville,  sends me and others this paper where he postulates that the ocean may be the main driver of CO2.

In the flurry of emails that followed, Joe D’Aleo provided this graph of CO2 variations correlated by El Nino/La Nina /Volcanic event years which is relevant to the discussion. Additionally for my laymen readers, a graph of CO2 solubility in water versus temperature is also relevant and both are shown below:


Click for full size images

Additionally, I’d like to point out that former California State Climatologist Jim Goodridge posted a short essay on this blog, Atmospheric Carbon Dioxide Variation, that postulated something similar.

UPDATE: This from Roy on Monday 1/28/08 see new post on C12 to C13 ratio here

I want to (1) clarify the major point of my post, and (2) report some new (C13/C12 isotope) results:

1.  The interannual relationship between SST and dCO2/dt is more than enough to explain the long term increase in CO2 since 1958.  I’m not claiming that ALL of the Mauna Loa increase is all natural…some of it HAS to be anthropogenic…. but this evidence suggests that SST-related effects could be a big part of the CO2 increase.

2.  NEW RESULTS: I’ve been analyzing the C13/C12 ratio data from Mauna Loa.  Just as others have found, the decrease in that ratio with time (over the 1990-2005 period anyway) is almost exactly what is expected from the depleted C13 source of fossil fuels.  But guess what? If you detrend the data, then the annual cycle and interannual variability shows the EXACT SAME SIGNATURE.  So, how can decreasing C13/C12 ratio be the signal of HUMAN emissions, when the NATURAL emissions have the same signal???


Here is Roy Spencer’s essay, without any editing or commentary:

Atmospheric CO2 Increases:

Could the Ocean, Rather Than Mankind, Be the Reason?


Roy W. Spencer


            This is probably the most provocative hypothesis I have ever (and will ever) advance:  The long-term increases in carbon dioxide concentration that have been observed at Mauna Loa since 1958 could be driven more than by the ocean than by mankind’s burning of fossil fuels.

            Most, if not all, experts in the global carbon cycle will at this point think I am totally off my rocker.  Not being an expert in the global carbon cycle, I am admittedly sticking my neck out here.  But, at a minimum, the results I will show make for a fascinating story – even if my hypothesis is wrong.  While the evidence I will show is admittedly empirical, I believe that a physically based case can be made to support it.

            But first, some acknowledgements. Even though I have been playing with the CO2 and global temperature data for about a year, it was the persistent queries from a Canadian engineer, Allan MacRae, who made me recently revisit this issue in more detail.  Also, the writings of Tom V. Segalstad, a Norwegian geochemist, were also a source of information and ideas about the carbon cycle.

            First, let’s start with what everyone knows: that atmospheric carbon dioxide concentrations, and global-averaged surface temperature, have risen since the Mauna Loa CO2 record began.  These are illustrated in the next two figures.




Both are on the increase, an empirical observation that is qualitatively consistent with the “consensus” view that increasing anthropogenic CO2 emissions are causing the warming.  Note also that they both have a “bend” in them that looks similar, which might also lead one to speculate that there is a physical connection between them.

Now, let’s ask: “What is the empirical evidence that CO2 is driving surface temperature, and not the other way around?”  If we ask that question, then we are no longer trying to explain the change in temperature with time (a heat budget issue), but instead we are dealing with what is causing the change in CO2 concentration with time (a carbon budget issue).  The distinction is important.  In mathematical terms, we need to analyze the sources and sinks contributing to dCO2/dt, not dT/dt.

So, let us look at the yearly CO2 input into the atmosphere based upon the Mauna Loa record, that is, the change in CO2 concentration with time (Fig. 3).


Here I have expressed the Mauna Loa CO2 concentration changes in million metric tons of carbon (mmtC) per year so that they can be compared to the human emissions, also shown in the graph.

Now, compare the surface temperature variations in Fig. 2 with the Mauna Loa-derived carbon emissions in Fig. 3.  They look pretty similar, don’t they?  In fact, the CO2 changes look a lot more like the temperature changes than the human emissions do.  The large interannual fluctuations in Mauna Loa-derived CO2 “emissions” roughly coincide with El Nino and La Nina events, which are also periods of globally-averaged warmth and coolness, respectively.  I’ll address the lag between them soon. 

Of some additional interest is the 1992 event.  In that case, cooling from Mt. Pinatubo has caused the surface cooling, and it coincides in a dip in the CO2 change rate at Mauna Loa.

These results beg the question: are surface temperature variations a surrogate for changes in CO2 sources and/or sinks?

First, let’s look at the strength of the trends in temperature and CO2-inferred “emissions”.  If we compare the slopes of the regression lines in Figs. 2 and 3, we get an increase of about 4300 mmt of carbon at Mauna Loa for every degree C. of surface warming.  Please remember that ratio (4,300 mmtC/deg. C), because we are now going to look at the same relationship for the interannual variability seen in Figs. 2 and 3.

In Fig. 4 I have detrended the time series in Figs. 2 and 3, and plotted the residuals against each other.  We see that the interannual temperature-versus-Mauna Loa-inferred emissions relationship has a regression slope of about 5,100 mmtC/deg. C. 

There is little evidence of any time lag between the two time series, give or take a couple of months.


So, what does this all show?  A comparison of the two slope relationships (5100 mmtC/yr for interannual variability, versus 4,700 mmtC/yr for the trends) shows, at least empirically, that whatever mechanism is causing El Nino and La Nina to modulate CO2 concentrations in the atmosphere is more than strong enough to explain the long-term increase in CO2 concentration at Mauna Loa.  So, at least based upon this empirical evidence, invoking mankind’s CO2 emissions is not even necessary. (I will address how this might happen physically, below).

In fact, if we look at several different temperature averaging areas (global, N. H. land, N.H. ocean, N.H. land + ocean, and S.H. ocean), the highest correlation occurs for the Southern Hemisphere ocean , and with a larger regression slope of 7,100 mmtC/deg. C.  This suggests that the oceans, rather than land, could be the main driver of the interannual fluctuations in CO2 emissions that are being picked up at Mauna Loa — especially the Southern Ocean.

Now, here’s where I’m really going to stick my neck out — into the mysterious discipline of the global carbon cycle.  My postulated physical explanation will involve both fast and slow processes of exchange of CO2 between the atmosphere and the surface. 

The evidence for rapid exchange of CO2 between the ocean and atmosphere comes from the fact that current carbon cycle flux estimates show that the annual CO2 exchange between surface and atmosphere amounts to 20% to 30% of the total amount in the atmosphere.  This means that most of the carbon in the atmosphere is recycled through the surface every five years or so.  From Segalstad’s writings, the rate of exchange could even be faster than this.  For instance, how do we know what the turbulent fluxes in and out of the wind-driven ocean are?  How would one measure such a thing locally, let alone globally?

Now, this globally averaged situation is made up of some regions emitting more CO2 than they absorb, and some regions absorbing more than they emit.  What if there is a region where there has been a long-term change in the net carbon flux that is at least as big as the human source? 

After all, the human source represents only 3% (or less) the size of the natural fluxes in and out of the surface.  This means that we would need to know the natural upward and downward fluxes to much better than 3% to say that humans are responsible for the current upward trend in atmospheric CO2.  Are measurements of the global carbon fluxes much better than 3% in accuracy??  I doubt it.

So, one possibility would be a long-term change in the El Nino / La Nina cycle, which would include fluctuations in the ocean upwelling areas off the west coasts of the continents.  Since these areas represent semi-direct connections to deep-ocean carbon storage, this could be one possible source of the extra carbon (or, maybe I should say a decreasing sink for atmospheric carbon?).   

Let’s say the oceans are producing an extra 1 unit of CO2, mankind is producing 1 unit, and nature is absorbing an extra 1.5 units.  Then we get the situation we have today, with CO2 rising at about 50% the rate of human emissions.

If nothing else, Fig. 3 illustrates how large the natural interannual changes in CO2 are compared to the human emissions.  In Fig. 5 we see that the yearly-average CO2 increase at Mauna Loa ends up being anywhere from 0% of the human source, to 130%.  

It seems to me that this is proof that natural net flux imbalances are at least as big as the human source.


Could the long-term increase in El Nino conditions observed in recent decades (and whatever change in the carbon budget of the ocean that entails) be more responsible for increasing CO2 concentrations than mankind?  At this point, I think that question is a valid one.


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Very interesting! This one will probably be very controversial. Still, this is an interesting result and Roy generally gives good insight.

Very important quote: After all, the human source represents only 3% (or less) the size of the natural fluxes in and out of the surface. This means that we would need to know the natural upward and downward fluxes to much better than 3% to say that humans are responsible for the current upward trend in atmospheric CO2. Are measurements of the global carbon fluxes much better than 3% in accuracy?? I doubt it.
That is something I have been saying in discussions with friends, colleagues, and family for some time–and receive mostly blank looks, for my trouble.
Nice “super Friday” today!


I’m not sure whether this is consistent (or at least compatible) with isotope studies, so it’d be nice to hear Dr. Spencer address that directly.
REPLY: he’s out of country until Feb 1st, so we’ll have to wait.

Make it a triple play Friday, with this Roy Spencer editorial on National Review Online at Planet Gore. Details here

Richard S Courtney

Dr Spencer’s article reaches similar conclusions to those in
Rorsch A, Courtney RS & Thoenes D, ‘The Interaction of Climate Change and the Carbon Dioxide Cycle’ E&E v16no2 (2005).
I expanded on that paper in a presentation at a climate conference held in Stockholm on 11 & 12 September 2006. I could provide Dr Spencer with a copy of it were he to contact me.
There are some surprising similarities between Dr Spencer’s article and my presentation. For example, his Figure 3 presents the same data in the same way as my Figure 1, and he draws the same conclusion from it as we do in our paper.
Importantly, our paper provides six models that each match the empirical data.
We provide three basic models that each assumes a different mechanism dominates the carbon cycle. The first basic model uses a postulated linear relationship of the sink flow and the concentration of CO2 in the atmosphere. The second used uses a power equation that assumes several different processes determine the flow into the sinks. And the third model assumes that the carbon cycle is dominated by biological effects.
For each basic model we assume the anthropogenic emission (a) is having insignificant effect on the carbon cycle, and (b) is affecting the carbon cycle to induce the observed rise in the Mauna Loa data. Thus, the total of six models is presented.
The six models do not use the ‘5-year-averaging’ to smooth the data that the IPCC model requires for it to match the data. But all of the six models match the empirical data. However, they provide very different ‘projections’ of future atmospheric carbon dioxide concentration for the same assumed future anthropogenic emission. And other models are probably also possible.
The ability to model the carbon cycle in such a variety of ways means that according to the available data
(1) the cause of the recent rise in atmospheric carbon dioxide concentration is not known,
(2) the future development of atmospheric carbon dioxide concentration cannot be known, and
(3) any effect of future anthropogenic emissions of carbon dioxide on the atmospheric carbon dioxide concentration cannot be known.
All the best


Al Fin
The following figures are from my laymans’ pov research I am compiling on the subject. (More on this later, Rev.)
I do not know the delta over time, but it seems quite plausible that man is the factor causing the CO2 “overflow”. (A bit over half of total output is sucked up by the other sinks.)
Remember, CO2 is a trace gas (c. 1/25 of 1% of volume), and the Atmosphere is the lesser of the three Great Sinks. So it seems quite reasonable to assume that man is responsible for CO2 buildup.
To put the overall exchange in perspective:
Atmospheric CO2 Cycle
Amounts in Bil. Metric Tons Carbon (BMTC)
Total Sinks:
Atmosphere: 730
Vegetation/Soil: 2000
Ocean: 38,000
Annual Input to Atmosphere/Output from Atmosphere:
Ocean: To Atm.: 88, From Atm.: 90, Difference: -2
Vegetation/Soil (Natural): To Atm.:119, From Atm.: 120, Difference: -1
Vegetation/Soil (Man): To Atm.:1.7, From Atm.: 1.9, Difference: -0.2
Industry: To Atm.: 6.3, From Atm.: 0, Difference: +6.3
Total: To Atm.: 215, From Atm.: 211.9, Difference: +3.1
Source: http://www.eia.doe.gov/oiaf/1605/ggccebro/chapter1.html
If oceans are warming (via PDO/AMO or whatever), they may be absorbing less or exuding more, or both. Then all bets are off.
But the above is what the DoE seems to think:
–The oceans suck up c. 2% more than they are putting out. (-2 BMTC)
–Vegetaion/Soil sucks up c. 1% more than it puts out (-1 BMTC)
–Agriculture sucks up c. 20% more CO2 than it puts out. (-O.2 BMTC)
–Industry is making the positive difference (+6.3 BMTC)
As to whether CO2 has the effect the AGW advocates say is, of course, an entirely different question.

Richard S Courtney

Evan Jones makes two common logical error. Before stating them, I point out that some people are trying to assess how carbon dioxide moves in and out of the atmosphere – which is a small part of the carbon cycle – by assuming the carbon dioxide content of that small part is not dominated by the variations in flows in and out of it from the much, much bigger other parts. This assumption may be correct but it is improbable for the following reason (that Mr. D’Aleos article also addresses).
The apparent accumulation rate of CO2 in the atmosphere (1.5 ppmv/year which corresponds to 3 GtC/year) is equal to almost half the human emission (6.5 GtC/year). However, this does not mean that half the human emission accumulates in the atmosphere, as is often stated. There are several other and much larger CO2 flows in and out of the atmosphere. The total CO2 flow into the atmosphere is at least 156.5 GtC/year with 150 GtC/year of this being from natural origin and 6.5 GtC/year from human origin. So, on the average, 3/156.5 = 2% of all emissions accumulate.
Evan Jones provides one estimate of the carbon dioxide moving in the carbon cycle. All the estimates are very gross, but another widely accepted estimate is provided by NASA and is presented in a diagram that is at
The diagram shows the amounts of carbon in the parts of the carbon cycle to be
the atmosphere 760 PgC (increasing at a rate of about 3 PgC p.a.)
the ocean surface layers 800 PgC
the deep ocean 38,000 PgC
plants and soils 2,000 PgC
Simply, the carbon in the air is less the 2% of the carbon flowing between above-listed parts of the carbon cycle. And the recent increase to the carbon in the atmosphere is less than a third of that ~2%.
Estimates of the flows of carbon between the parts of the carbon cycle are also provided in the diagram. Please note the squiggles which indicate that the flows between deep ocean and ocean surface layers are completely unknown and it is not possible even to estimate them (although some organizations do provide guesses).
The NASA diagram also provides an estimate of the carbon in the ground as fossil fuels. They estimate this to be 5,000 PgC and it is being transfered to the carbon cycle (by humans burning fossil fuels) at a rate of 6.5 PgC p.a.
In other words, the annual flow of carbon into the atmosphere from the burning of fossil fuels is less than 0.02% of the carbon flowing around the carbon cycle.
Like Roy Sencer, I find it hard to believe that so small an addition to the carbon cycle is certain to disrupt the system because I know of no other activity in nature that is so constant as to only vary by less than ± 0.02% p.a..
Now to the logical errors.
Firstly, there is no “build up” of CO2 in the atmosphere.
The seasonal variation at each measured locality is much more than the annual increase. Simply, at every measurement locality natural processes remove between about six times more than the annual increase each year then put it back again each year. (At Mauna Loa – as Dr Spencer’s Figure 1 shows – natural processes remove an order of magnitude more than the annual increase each year then put it back again each year.) The annual rise is the residual of the seasonal fluctuation.
Clearly, there is a disturbance to the seasonal variation of the carbon cycle at each locality and not a “build up” (nor “accumulation” as the IPCC says).
The anthropogenic emission could be considered to be – in effect – a “build up” (or “accumulation”) if the anthropogenic emission were larger than the seasonal variation and/or if the system of the carbon cycle were near to saturation in CO2 so it fails to adjust for all of the relatively small anthropogenic additions to the CO2 in the air. However,
(a) the anthropogenic emission is less than a third of the seasonal variation, and
(b) the rapid changes to atmospheric CO2 concentration of the seasonal variation indicate that during each year the system very rapidly adjusts to seasonal changes that are much greater than the anthropogenic emission each year (in some places more than an order of magnitude greater; e.g. at Alert, Canada). The anthropogenic emission is to the air, but the rapid changes in atmospheric CO2 concentration exhibited by the seasonal varaiations do not suggest that the system is near to saturation that would prevent the system from sequestering the anthropogenic emission from the air.
Secondly, it is a logical fallacy to attribute the rise in atmospheric to any one cause (e.g. the anthropogenic CO2 emission) when several variations to the flows exist.
The seasonal variations in atmospheric CO2 are larger than the anthropogenic emission of CO2. This demonstrates that there are larger changes to natural flows in and out of the air than the flow to the air that is the anthropogenic emission. The issue is the concept of causality. Let us suppose that a number of natural inflows have increased, while others have decreased. Likewise for outflows. The net accumulation cannot be ascribed to just one change, such as the anthropogenic contribution. It is caused by all the changes taken together.
There is a simple test that demonstrates this point that could be called the “but for” test. We can say that but for the anthropogenic contribution, the net accumulation would not have happened (all else being constant). This is often said (e.g. by IPCC). However, the same thing can be said about any combination of the natural changes that sum to or exceed the net accumulation. Ascribing the cause to the anthropogenic contribution alone is therefore a fallacy.
Does any of this prove that the anthropogenic emission is not the cause of the rise in atmospheric CO2 ?
No, but it does demonstrate that other causes are possible and are more likely.
All the best

I completely disagree with Roy Spencers comment (as good as with Richard’s, after a long, ongoing discussion).
Basicly, as Evan Jones already reacted, the total sum of all natural in/out flows to/out of the atmosphere are negative in all years (except in strong El Niño years like 1972 and 1998, although I have different figures). That means that no matter what the individual flows were, even if these are 100 or 1000 times the emissions, the net effect of all natural flows over a year, and certainly over several years, is a net loss of CO2 out of the atmosphere. That means that the net addition from nature to the observed increase is zero (even if a lot of CO2 molecules were temporarely added, within a year more molecules – the same or others – were removed by the same cycle or different cycles).
If we take into account the different reactions of CO2 levels on temperature variations in the past and present, then we have following figures:
– Over the ice ages / Interglacials (Vostok, Epica C ice cores): 8 ppmv/°C
– The MWP-LIA cooling (Law Dome ice core): 10 ppmv/°C
– The current CO2 variability over the trend (Mauna Loa): 2-4 ppmv/°C
This means that the about 1°C increase from the LIA till current temperatures (including Pinatubo and El Niño’s) is maximum responsible for 10 ppmv of the 100 ppmv increase in CO2 since the start of the industrial revolution…
More discussion can be found at CA, here: http://www.climateaudit.org/?p=2469

In addition, about the rate of increase:

Roy Spencer compares the increase slopes of a few extreme years with the slope of the increase in the atmosphere (which in the following year go as fast back as they rised). But one should also compare the slope of the emissions to the atmosphere with the increase, which is double the increase.
One should look at the net result of a complete cycle (El Niño ánd La Niña, summer ánd winter releases/uptakes), not one halve cycle and forget the other halve. The difference between cycles and the emissions is that the latter is a one-way process, the former are two-way processes, which are more or less in equilibrium after a full cycle, except for temperature influences.
As the increase is mainly a two-variable process, one can give a formula like:
dC(atm) = 0.5 F(emissions)/0.21 + 3*dtemp
where dC(atm) is the yearly change in CO2 (ppmv)
F(emissions) the emissions in GtC; 0.21 the conversion factor GtC->ppmv
and dtemp the change in temperature over a year.
Thus the emissions are responsible for most of the increase, while temperature is mostly responsible for the variation in increase…

Gary Gulrud

Dr. Spencer is obiously not off his rocker. I remember a Sci. American feature in the late ’70s focussing on the Oceanic lacunae of the carbon cycle. The temperature dependent partial pressure of CO2 controlling atmospheric abundance was presented as orthodox Earth Science. The pseudoscience cult has so dominated with their ‘sink’ obfuscations that it now bubbles up as novel, nonetheless, Dr. Spencer’s critical treatment of CDIAC outputs is new to me.
I’d be especially interested in his thoughts on this: Pinatubo was a 5 on the explosivity index. As 20% of the 10 km^3 ejected was gaseous to support the Plinian column, my rough estimate indicates a CO2 pulse on the same order as the yearly anthropogenic one. Where is it in the Mauna Loa data?

Evan: Interesting analysis. I suspect the total system is more complex and dynamic than that, however. We will have to get a bit closer to the action to find out what is really happening.
Natural systems are typically elastic, with the ability to expand or contract based upon environmental factors. The same is no doubt true of the ocean’s ability to absorb CO2, or of the biosphere of land and sea to sequester CO2.
Despite the human’s best attempts to destroy tropical forest, for example, tropical vegetation overall seems to be expanding based upon latest satellite counts.


The question is, what were the numbers before the 6.3 BMTC turned up? CO2 was presumably not vanishing at the rate it is now increasing, so those numbers must have been quite different fifty years ago.
The increase in the natural sinking of carbon is presumably partly to do with the increased CO2 partial pressure, but has it been shown that all of it is? The “solubility pump” flux is also strongly temperature dependent, so if there have been changes to the polar-tropics temperature difference over the past century, that would also affect these numbers.


Evan, could it be that changes in the ocean modulate the addition of our emissions to the atmosphere, becuase these changes would alter the properties of the ocean as a sink?

John M

Dr. Courtney,
Since Roy Spencer is out of the country, perhaps you can address my question above about carbon isotopes. I’m sure you have addressed this issue in your publications, so it would be nice to address it here as well.

Peter Hartley

I thought one could get other evidence on these matters by looking at the isotopic composition of the CO2 and also by looking at the correlation between CO2 changes and change in O2. With regard to the latter, combustion increases CO2 while decreasing O2, while increased photosynthesis does the opposite. Cement manufacture releases CO2 without changing O2. On the other hand, I think that both CO2 and O2 are released together from the ocean — and in roughly the same amount — as it warms. With regard to the former, I seem to recall reading somewhere that the isotopic composition of the carbon in fossil fuels (and limestone used to make cement) differs from the average composition in current sinks and that can be used to look at where the CO2 is coming from.

About the stable isotope (d13C) ratios, there are two interesting graphs:
One made by the late Bert Bolin:
which shows the decrease of O2 and increase of CO2 vs. the human emissions.
The other by Böhm ea. about the d13C changes in coralline sponges over 600 years: http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
The resolution is less than 5 years and the accuracy is good enough to detect 1 GtC from fossil fuel burning or 4 GtC from deep ocean upwelling.
More evidence for man-made increase is in the following:
– CO2 levels in the upper oceans follow the air measurements
– pH levels in the upper oceans are decreasing
– d13C ratios are declining in the atmosphere and with some delay in the upper oceans
This is a good indication that the (deep) oceans are not the source of the extra CO2, as the (deep) oceans have a higher d13C ratio than the atmosphere.
– d14C levels were declining pre-bomb testing at such a rate that 14C dating needed to be corrected for the decline since 1875 (fossil fuels are completely depleted of 14C).
– oxygen levels are declining in near ratio with fossil fuel use.
As there is a small deficiency in oxygen use, that indicates that vegetation is not a net source of CO2, but a net sink (about 2 GtC/yr), as oxygen is produced by CO2 uptake (see Bolin’s graph).
The only net source for increasing CO2 levels are the human emissions…


Okay, Ferdinand, humans are a net source at all times, but other things aren’t. But varying properties of sinks could alter how much gets into the air, correct? So warm years in the ocean mean that the oceans absorb less CO2, right? So might that be why CO2 growth rate appears to be correlated well with ocean temperatures? Seems reasonable to me.

Steve Hemphill

Ferdinand says: “As the increase is mainly a two-variable process”. I don’t think we can say that. There are at least three variables – anthropogenic, oceanic, and flora. Since the trees and bushes in my yard this year are the same as last year, I feel fairly confident in saying that the annual variation due to flora is pretty much invariant. That leaves anthropogenic, a constant (but escalating) contribution, and the ocean, which is what this is all about.
One can cite cores as evidence of 8 to 10 ppm per K, but that is a long term average. Average age of air at Vostok is 4,000 years older that the age of the ice at that depth, so we have an extremely long averaging period. One could argue that 4,000 years is a long enough time for flora to adjust to, for example, a mammoth influx of CO2 due to warming. The expansion of flora under these conditions will sink a great deal of CO2 over millennia.
This seems to be backed up by looking at the rate of change of CO2 by age in the cores. The rate of change, based on a 4,000 year average age, cannot possibly be as fast as it is without the introduction of some extreme values. Over 10% of the time Vostok cores (from CDIAC) show a jump of over 0.1ppm in 10 years, something improbable with multi-millennial averaging, unless there is a spike.


I have not yet had time enough to read all the comments. I am “hard at work”.)
I want to be clear, though, I am NOT expressing a hard and fast opinion, I am merely being a messenger of DoE data.
And yes, I provided a simplified version dealing only with atmospheric exchange and I am aware there’s a lot more to it than that.
I’ll be back as soon as I have time to comment on the comments and maybe put up the other carbon cycle version I have in my “library”.
Also, for the record, I am a strong advocate of Anthony Watts and think his work is both groundbreaking and vitally important.

Of course, ocean CO2 release (mainly in the tropics) and uptake are influenced by temperature. But that is less than many expect: the temperature influence today, based on the Muana Loa data and the influence of the 1998 El Niño and the 1992 Pinatubo eruption shows a 2-4 ppmv/°C influence (Dr. Spencer calculated 4,300 mmtC/deg. C, which is 4.3 GtC/°C or about 2.1 ppmv/°C).
Dr. Spencer’s conclusion is that increased temperatures (more El Niño’s) may be the cause, but these are often followed by La Niña’s, which cool the sea surface… Thus what is of interest is the total temperature change over the full period.
The global temperature increase 1959-2003 is about 0.6°C, which gives with 3 ppmv/°C an increase of about 2 ppmv of the 60 ppmv we see in the same period… Doesn’t sound that temperature is the main driver of the total increase.
That temperature and CO2 levels are in close connection can be seen in the seasonal variations: For the NH, we see an average amplitude of about 20 ppmv. Translated to CO2/temperature ratio, we see again a short-term ratio of 2.6 ppmv/°C. In the SH the amplitude is much smaller (less vegetation, more oceans).
But still, there is a correlation between temperature and CO2 increase rate, as you say, as indeed the release/uptake of CO2 from/to the ocean’s surface is governed in part by temperature.
But the increase itself is mainly governed by the emissions.
Instead of focusing on yearly increases, one should look at the accumulated emissions and the increase of the CO2 levels. The correlation between both is 0.96.
See: http://www.ferdinand-engelbeen.be/klimaat/klim_img/emissions.gif
I have played around with the formula which should calculate the CO2 increase from the emissions and the temperature variation. This can be seen at:
The formula used was: dCair = 0.5415*F(emissions)/0.21 + 3*dtemp
This resulted in a mean difference of trends (observed-calculated)= 0.00; correlation between the series = 0.65; R^2 = 0.42 (which is poor); stdev of the calculated and observed series = 0.55 ppmv
It looks like that the calculated CO2 increase/variations are leading the observed ones.
By lagging the CO2 result from temperature changes one year, the calculated variation was lagging the observed:
The same coefficients were used, no difference in trends and stdev, correlation between the series = 0.732; R^2 = 0.536 (which is fair).
Thus the real lag of CO2 increase rate after temperature changes is somewhere between 0 and 1 year…


Interesting discussion. I’d like to note that prior to Mauna Loa circa 1955, we are led to rely on ice core – shallow ice core CO2 readings. These have several significant divergences from the chemical CO2 analysis as described in the Beck paper. Further, the shallow ice core data gas readings is as best as I could establish from the several background articles, a bit iffy, perhaps at best having a plus or minus 10 ppm accuracy.
Going back fifty years prior to 1955, we have there a ramp up of industrialization and CO2 emissions. Understanding that our knowledge of actual CO2 concentrations is limited as above described, nonetheless extending the analysis to the prior time period might show some things up. Therein we have the prior PDO cycle and other ocean cycles with known effects.
Then again, this may raise more questions and varibles and confuse the matter rather than help it….

Johnny Swammi

Developing, testing, validating and invalidating theories using well-established or newly observed facts is a tenet of the scientific method, a skill that many posting as experts on this site have yet to demonstrate.
A challenge to Roy Spencer, Richard Courtney, Stevo, Andrew and Steve Hemphill (and others): Demonstrate publically your skills in the scientific method by addressing the following —
Using known and established tenets of geochemistry and physical chemistry, describe how the delta-13-C data shown in Figure 4 of Bohm et al (2002) (conveniently provided by Mr. Engelbeen in his post as http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif ) does or does not support your theory that anthropogenically produced carbon (derived from fossil fuels) is NOT the cause of the increase in the content of atmospheric (and ocean) carbon dioxide shown by peer-reviewed data to have occurred in the last 1,000 years.
You may develop or derive new tenets of physical chemistry and geochemistry to support your claims, but these new tenets must be supported by existing data or data you (or others) derive from peer-reviewed experiments or observations. If your claim(s) include other sources of carbon as being the prime source of any excess carbon dioxide, you must explain how these sources explain both the long term trends in the Mauna Kea carbon dioxide data and the Bohm, et al delta-13-C data simultaneously. You may use either existing peer-reviewed data or that which you collect and are validated by peer-review.
I recommend reading the following article before starting on this challenge: http://ecophys.biology.utah.edu/public/Isotope_course_readings/Spero%202.pdf . It is not hard to understand for a PHOSTA. Oh, and I suggest you follow the example of Bohm, et al and state clearly where each piece of data comes from (i.e., a reference) since others, who are not a PHOSITA, might want to try out their skills in the scientific method and check your facts and logic.
I suspect that none will take on this challenge: (a) You are not a PHOSTA and lack the background, knowledge and critical thinking skills it takes to understand the existing data and its implication in terms global geochemical systems; (b) You will be unable to find through literature research or create via experiment or observation the data needed to come to a self-consistent derivation and will thus ignore this challenge in the face of embarrassment; or (c) You will want to conveniently ignore the myriad of data presented by Bohm and others since these data contradict your theory and your working studiously to prove otherwise is, well, just inconvenient.
Have fun!
Just FYI, atmospheric CO2 (the Keeling curve) is measured at MAUNA LOA, not “Mauna Kea” (from your 4th paragraph). Mauna Kea has the Keck Observatory, not the CO2 lab. It’s always a good idea to check your own facts before you dictate terms to others.

Courtney says

The seasonal variation at each measured locality is much more than the annual increase. Simply, at every measurement locality natural processes remove between about six times more than the annual increase each year then put it back again each year. (At Mauna Loa – as Dr Spencer’s Figure 1 shows – natural processes remove an order of magnitude more than the annual increase each year then put it back again each year.) The annual rise is the residual of the seasonal fluctuation.

However this is true only for the northern hemisphere. If you look at the data from the Scripps monitoring sites you see that the most extreme annual variations are in the most northernly of the stations (Barrow/Alert) and the least in the southernmost (Baring Head, Kermadec Island). There is a smooth increase as one goes from south to north. The South Pole station shows a bit more variation than Kermadec. The link has a nice map.
The obvious correlation is the more water in the latitude band, the less variation in annual CO2 concentration. Since even the seas warm and cool during the year this would seem to knock Spencer and Courtney’s ansatz into a cocked hat, if it had not already been taken apart by Engelbeen and others

Tony, that’s what a scientist must always do with something unexpected. As Colyn Doyle put it having eliminated the impossible, what remains must be the truth. The problem is you need a lot of experience to eliminate the impossible, and there are a lot of naive people out. As Sean Carroll put it to the wanna be next Einsteins, first acquire basic competency in whatever field of science your discovery belongs to.


Don’t get me wrong. Nothing would delight me more than to be in error. And I admit the amount is smaller than the MoE. But it has rather steadily accumulated (according to measurements which may or may not be entirely accurate) through both cool and warm. That’s the reason it isn’t making it as such a great temperature proxy!
Oh, yes. Only the expert may testify. But never, ever forget it is the layman juror who must, in the end, “determine the facts”. The expert is excuded from the jury, and for good reason.
Mr. E.
I think you may well be right.
On the other hand, whether CO2 is the–main–driver of the recent warming measurements is yet to be seen. It does not correlate very well. And if Mr. Watts’ Inconvenient Photographs are any indication at all, the surface stations have actually been measuring encroaching heat sinks and waste heat for the last two or three decades.
A modest temperature increase is greatly exaggerated by a heat sink.
And yes, the carbon cycle is indeed more involved. Here’s one I hammered together a while back from several sites (including the one RC provided:
The Greater Carbon Cycle
Air & Water
From: Organic Compounds/Animals (Decay, Cellular Respiration), Organic Compounds/Plants (Decay, Cellular Respiration, Combustion), Limestone, Coal, Oil (Industry), Volcanoes (CO2)
To: Plants (Photosynthesis), Limestone, Coal, Oil
Organic Compounds/Animals
From: Animals
To: Air & Water (Decay, Cellular Respiration)
Limestone, Coal, Oil
From: Air & Water
To: Air & Water
From: Air & Water
To: Animals, Organic Compounds/Plants
Organic Compounds/Plants
From: Plants
To: Animals (Consumption), Air & Water (Decay, Cellular Respiration, Combustion)
From: Organic Compounds/Plants , [ Plants ], [ Animals ]
To: Organic Compounds/Animals
To: Air (CO2)
And another take:
The Oxygen Cycle
From: Animals (CO2), Plants (O2)
To: Animals (O2), Plants (CO2)
From: Atmosphere (CO2)
To: Atmosphere (Photosynthesis/CO2, Respiration/O2)
From: Water (CO2)
To: Water (O2),
From: Atmosphere (O2)
To: Atmosphere (CO2)
From: Animals (CO2), Plants (O2)
To: Animals (O2), Plants (CO22)
From: Water (O2)
To: Water (CO2)
From: Algae (O2), Atmosphere (O2, CO2)
To: Algae (CO2) Fish (O2), Atmosphere O2, CO2)
[I’ve also hunted up and compiled simple cycles for Energy (Greenhouse) Cycle, Nitrogen, Sulfur, Phosphous, Life Energy, and Water.]
Just an amateur look at the back-and-forth. At some point I am going to try to compile common carbon into a single entity. I may try to create link between the hydrogen aspects which run through many of these.
It’s all in the point of view. All a body has to do to make Ptolemy “correct” is to take a working solar system model, is grab it by the earth and then watch the sun and planets spin weirdly about …

I decided long ago that much of this debate about mankind’s relative impact on the planet could be resolved if only those involved stayed away from airplanes and drove the length of the continents by car.
Or by ox cart.

Steve Hemphill,
I used “two-variable” process for the emissions and temperature influences. The latter involves oceans and vegetation.
The interesting feature of temperature on oceans and vegetation is that the CO2 uptake/release is opposite of each other.
Oceans continuous release CO2 in the equatorial band (including deep ocean upwelling in the Pacific) and dissolve CO2 near the poles (including deep ocean downwelling by the THC in the North Atlantic). The main seasonal variation is due to the mid-latitudes, where changing ocean surface temperatures release CO2 in summer and absorb CO2 in winter.
Vegetation goes the opposite way: large CO2 uptake in summer (including ocean algues) and continuous release of CO2 during the year from vegetation decay (without uptake in winter from leafless trees).
This makes that the about 100 GtC exchange oceans/atmosphere and 50 GtC exchange vegetation/atmosphere are in countercurrent and cause only a 20 GtC (10 ppmv) global amplitude over the seasons. The one-way emissions are about 35% of the two-way seasonal flows in the atmosphere, but average 200% of the residual variability of the seasons over a year.
About ice cores (of interest for Mhaze too):
There is a difference between the lag of gas age after ice age dating and the resolution of the gas sampling. The lagging is a question of closing depth of the bubbles, while the resolution is a matter of diffusion of CO2 through the firn before the bubbles close and the number of layers necessary to have enough sample for a CO2 measurement.
For the Vostok ice core, the lagging is several thousands of years, but the resolution is about 600 years. The accuracy of the measurements are no way better than 1 ppmv, smaller variations are within the accuracy. The 8 ppmv/°C is based on the big shifts of about 10°C and about 80 ppmv for the ice age – interglacial transitions and reverse. That indeed are very long-term averages and probably involve the deep oceans, which is not the case for current (2-4 ppmv/°C) temperature changes.
High accumulation ice cores have a better resolution (about 60-80 years) and because of the one-way CO2 increase, the most recent layers only have a 10 years ice-gas age lag and a 5 years resolution. This resulted in an overlap of about 20 years for the Law Dome gas age data and the South Pole atmospheric measurements. The data of the South Pole atmosphere are within the +/- 1.2 ppmv accuracy of three ice cores (with different drilling methods) of Law Dome. See Etheridge ea.: http://www.agu.org/pubs/crossref/1996/95JD03410.shtml
The overlap is here: http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_sp_co2.jpg
About Beck’s historical data vs. ice cores: I don’t want to (re)start the discussion of Beck’s data here. It is sufficient to say that most measurements had an accuracy of 10 ppmv, but that most measurements were done at places where huge local production (vegetation as well as human emissions) was present. The only measurements taken at sealevel and/or coastal stations for the assumed peak period 1935-1950 (+ 100 ppmv 1942!) include the ice core values within the data variability.
And one need to take the comments of Jaworowski about ice core CO2 accuracy with a lot of salt, I noticed several remarks of him which simply aren’t true…
But I agree, even if human emissions are the sole cause of the increase, that doesn’t tell us anything about the influence of more CO2 on temperature…


“Or by ox cart.”
You would be surprised at the damage preindustial man did to the land. There are more of us today, but the environmental impact per person is miniscule compared with the past (and a good thing, too!). And that is mostly on account of the internal combustion engine. The IC engine has deletrious direct effects but many unsing indirect environmental (and other) benefits. And, above all, one must consider the overall environmental impact to land and air of what it replaced–bitumens, wood, and the horse–and those oxen you mention.
Consider that double-take line from Home onthe Range: “And the skies are not cloudy all day.” Also consider that Europe was one big forest, once.


There seems to be a consensus that the 3% of CO2 emissions that are anthropogenic are causing a rise in atmospheric CO2 concentration. Supposedly 50% of these emissions stay in the atmosphere. If this is true doesn’t it stand to reason that atmospheric CO2 concentrations would be falling if there were no anthropogenic emissions?
Taken to it’s logical conclusion one could conclude and then confirm with GCM’s that anthropogenic emissions are preventing a cascading runaway ice-age.


“d13C ratios are declining in the atmosphere and with some delay in the upper oceans”

If you are trying to convey the idea that d13C isotope data could account for the exact contribution of manmade CO2 in the atm concentration increase, I must disagree.
Appart from saying that d13C ratios are “consistent” (see IPCC 4AR chapter 7) with anthropogenic CO2 emission, nothing QUANTITATIVE can be said by isotope observations, neither with d13C, nor with C14. We can go further with numbers if you want but you should have known numbers don’t sum up.
The CO2 balance is so fuzzy that current “theories” must rely on the anti-science notion of “missing sink” (rephrased “residual carbon sink” by the IPCC in 4AR, see Wood Hole) to account for what may happen to 1/3 of anthropogenic CO2 emissions.
So the questions raised by Drs Spencer and Courtney about the outcome and the real influence of manmade CO2 and the caveats about data (huge) uncertainties remain valid.

“…even if human emissions are the sole cause of the increase…”

This is something the current science can’t say. Nobody knows if human emissions account for 30%, 60% or 100% of the concentration increase. So it’s out of the domain of refutability.


“the most recent layers only have a 10 years ice-gas age lag and a 5 years resolution.”

If icecores enables 5 y resolution CO2 measurements, we should have proxies data for up to year 2002 and plenty of them. The bubble close-off, reactive decay, diffusion… problems shouldn’t exist. But I’m not aware such data exist or are properly archived. Your Law Dome graph shows sparce data, “adjusted” with some methods, from different locations, with end date in the late 70s. Not exactly an illustration of a high quality 5 y resolution serie that would put to rest the divergence-calibration problem (between proxies and direct data).
I’m not saying such CO2 proxies don’t exist. I’d just love to see them.


Thanks for your input, it’s been very interesting. I’m not here to make any sort of case for or against, but to try to understand how it works better.
A few questions:
Where you say “More evidence for man-made increase is in the following” I don’t understand why some of those constitute evidence. The d13C/d14C levels show that fossil carbon has gone into the atmosphere and oceans, but doesn’t say the deep ocean hasn’t contributed any more (or less). Think of it as a tank of water with big pipes running in and other big pipes running out, and the rate of flow varying with both the level of the water, and some valves controlled by other stuff like temperature. You also pour in a small amount of dyed water. Now even if the flow has been varied by the big pipes, there’s still going to be an increasing level of dye in the water, until the concentration is high enough that the amount of diluted dye going out of the bigger pipes equals the amount of dye coming in. Certainly, not all of the dye is hanging around – that’s what Tom Segalstadt keeps going on about. The picture the layman normally gets is of a tank with tiny natural pipes in and out, and a huge anthropogenic pipe pouring in water with nowhere to go, and that all this new CO2 consists of fossil carbon. We need to get a clear picture of what is actually going on from the scientists, so that we can stop annoying them with these simplistic misunderstandings.
The oxygen level must decrease because carbon is being converted to carbon dioxide (and the hydrogen in hydrocarbons to water), but that doesn’t say anything about where it ends up. Is that oxygen ending up in the air or the water or the biosphere? Bringing in the oxygen cycle adds a whole new level of complexity, and would require a whole lot more discussion for us to be sure there was no other explanation for the lowering oxygen level. There may be good evidence there, but the argument is incomplete. Vegetation is a net sink of 2GtC/yr, but what if it would have sunk 4GtC/yr if it wasn’t for some other effect? Then that effect would be one of the causes of the accumulation. It doesn’t help me to understand.
The main argument I see is one you didn’t mention explicitly – that past temperature changes haven’t led to corresponding CO2 changes (unless there’s something badly wrong with CO2 proxies, which I’ve seen no convincing evidence for).


In a later comment, you speak of the 2-4 ppmv/°C sensitivity of CO2 levels to temperature. I don’t understand this figure. Firstly, the effect of temperature is surely on the flow, not the level? There ought to be some time units in there, unless you’re talking about some sort of equilibrium level? (Same goes for Dr Spencer, of course.) Secondly, what is that temperature? The global average, the average ocean temperature, or the temperature at the places where CO2 is absorbed/emitted? Since the solubility is a non-linear function of temperature, it matters, and you could possibly get some sort of effect from changes in distribution of temperatures (over time or location) without changing the average.
Similarly, you mention the seasonal temperature changes and their effect on CO2 level. The effect of the flow in and out of vegetation is a non-linear and integrated function of temperature, and the effect on the solubility pump is surely on the flow rate? This is the integrated change over about a year. If the 0.6C global mean anomaly change means a 2 ppmv change in CO2, and that is accumulated over 40 years, wouldn’t that give an 80 ppmv total? I don’t seriously think it works that way, but confusing rates with levels doesn’t make it obvious why such reasoning must be wrong.
I don’t know – your reasoning may well be perfectly correct for reasons that you’ve skipped over in order to be concise. But by skipping over them you just cause more confusion in those unable to fill in the gaps for themselves. They’re not convinced, they don’t understand any better, and when they find out that there are huge gaps in the argument you’ve given them (as they inevitably do) they immediately jump to the conclusion that they’re being taken for fools. (Take note, Eli and Swammi.)
Eli, There are many who would like to acquire a basic competency in the area, but when they try they at first find only these simplistic cartoon models, that are nevertheless presented by authoritative scientists as the truth. They can’t tell which ones are intended to be taken seriously, because they’re not told. When they start picking holes in them (as Dr Spencer has here), they’re told they’re fools and there’s another layer that the famous scientist didn’t explain to them, and an endless series of papers in journals they can’t get access to that each give one tiny bit of the jigsaw puzzle.
Make it easy for them. Provide an accessible explanation all in one place that fills in all the gaps and doesn’t fudge anything. (And everything elsewhere that is fudged should be marked as such.) As Richard Feynman said, if you can’t explain the science in terms an educated layman can understand, then you don’t really understand it yourself. And as Sir Arthur Conan-Doyle’s detective lamented so often, his feats of reasoning were always so absurdly obvious once they had been explained.

Steve Hemphill

First off I must say I wholeheartedly agree that just because CO2 is increasing does not mean it is the causative agent of the warming of last century, which seems to either have begun to decline or plateaued, depending on which analysis you look at (except GISS, which for some reason is out there all by itself).
Then, Huxley said “The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, scepticism is the highest of duties; blind faith the one unpardonable sin.”
which dispenses with the dogmatic narrowmindedness of Swammi.
To the point of this particular discussion, CDIAC says the *average* difference in age between the ice and the air at a depth is 4,000 years. You say (I suspect well documented) that the resolution is within 600 years. Leaving alone for the moment the weighted bubbles below the 4,000 year mark, how do you explain that there is no mixing between open bubbles for over 3,000 years?


A challenge to Roy Spencer, Richard Courtney, Stevo, Andrew and Steve Hemphill (and others): Demonstrate publically your skills in the scientific method by addressing the following —
Using known and established tenets of geochemistry and physical chemistry, describe how the delta-13-C data shown in Figure 4 of Bohm et al (2002) (conveniently provided by Mr. Engelbeen in his post as http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif ) does or does not support your theory that anthropogenically produced carbon (derived from fossil fuels) is NOT the cause of the increase in the content of atmospheric (and ocean) carbon dioxide shown by peer-reviewed data to have occurred in the last 1,000 years.

The Bohm et al’s delta-13-C data shown in Ferdinand’s graph does in NO WAY demonstrate human emissions cause the increase in CO2 atmospheric content. And certainly not in ocean (sic) CO2 content since no reliable measure exists there (if you are thinking about ocean pH change, forget about it, nobody has observed it apart from models).
Let me elaborate :
d13C is supposed to decrease because fossile CO2 – from oil, coal, nat gas – are depleted of C13 (d13C=-26/1000) compared to natural CO2 (-7/1000). So by measuring d13C, one *should* be able to know what percentage fossile CO2 accounts for the concentration increase.
Then using a simple mixing law, if you suppose concentration increase is due integrally to human emission (ie fossile CO2), you should observe a d13C = -13,3/1000. The problem, a big one, is that the real value you find is just -9/1000 that is just 30% of the target from the hypothesis & theory above.
Conclusion: contrary to what you hear very often but without further explanation, isotopic dosage can NOT tell you which % fossile CO2 accounts for the atmospheric increase. No way.


Ferdinand, Demesure.
I was just trying to indicate that extending the analysis back to say, 1880 with our best estimates of historical CO2 might yield some interesting results.
Do it with ice core dated CO2, and also with some group of historical CO2 by chemical means. Use the same analysis as for the recent period.
Might be something interesting there, might not. The fact there are controversies does not mean that entire period (1880-1955) should be excluded from study and analysis. Bad idea.

Dear all,
Here I try to address the most important points in Dr. Spencer’s and Richard Courtney’s essays where we differ in opinion.
Before we start, we need to be sure that we use the same definitions with the same meaning.
Emissions is used for all increases by Dr. Spencer: as well as for the human emissions as for the increase in the atmosphere (whatever the source). In the following emissions is exclusively used for anthro emissions.
Accumulation is by several used as the increase in % within a mass (of CO2), while others (myself included) use it as an increase in total mass. We use in the following accumulation for both, but add “in %” or “in mass” to make the distinction.
The accumulation
Richard made a statement that the total CO2 into the atmosphere is 156.5 GtC, of which 150 GtC/yr from natural inflow and 6.5 GtC/yr from emissions. Of this only 3 GtC/yr accumulate in mass in the atmosphere, thus only 3/156.5 = 2% of all emissions accumulate in mass.
Here we see the first logical error: the 6.5 GtC/yr emissions are not a part of the seasonal cycle of about 150 GtC/yr, which is composed of about 90 GtC seasonal (summer, oceans) increase, about 92 GtC (winter, oceans) decrease, 61.5 GtC decrease (summer, vegetation) and 60 GtC increase (winter, vegetation). For an attempt to make a rough estimate (+/- 30%) of the seasonal flows, see Battle ea..
Thus while the accumulation in CO2 mass is only 2% of the inflows, the seasonal inflow is a part of a cycle and the total natural cycle shows a net loss of about 3.5 GtC/yr. Thus the natural cycle has a negative accumulation in mass to the atmosphere and the full accumulation in mass of 3 GtC/yr in the atmosphere thus is from the emissions. Which makes that about halve of the emissions accumulate in mass in the atmosphere.
How much of the original emissions in % accumulate in the atmosphere is of a different order. A lot of molecules is exchanged over the seasons and by continuous flows (equatorial to polar oceans). About 20% of the atmospheric CO2 molecules are exchanges between the atmosphere and oceans/vegetation over a year. That means that about 80% of the emissions accumulate in % in the atmosphere, the first year of the emissions. The next year, without further emissions, again 20% of all molecules are exchanged and 80% of 80% of one-year emissions stays in the atmosphere. Thus the half-life time (the time that 50% of any addition of specific molecules, in this case 13C depleted CO2 stay in the atmosphere) is about 5 years.
This is based on the fate of the one-time addition of extra 14C from nuclear bomb testing in the 1950-60’s.
The real accumulation in % of the emissions in the atmosphere can be calculated, as there is a decrease in d13C in the atmosphere (ice cores-firn-Mauna Loa). Of total atmosphere only about 8% is from the emissions (65/800 GtC), and from the upper oceans only 3.5% (35/1000 GtC) is from human origin. Total 100 GtC from human origin still reside in the atmosphere and upper oceans. The rest of the over 300 GtC emissions since 1850 is either somewhere in the deep oceans (unmeasurable in that mass) or in vegetation (only quantitative since 1990, calculated from oxygen measurements).
The influence of flows and mass
Richard makes a lot of the huge carbon reservoirs and huge flows between the reservoirs, compared to the small amount that humans add to the atmosphere.
To be short on this: reservoirs have not the slightest influence on other reservoirs (including the atmospheric reservoir), if there were no flows/cycles between them.
Take the deep oceans: the estimated flow of 100 GtC between deep oceans (38,000 GtC) and upper oceans is only 0.26% of the deep ocean carbon mass.
Carbon cycles have not the slightest influence on accumulation in mass, if there was no imbalance between the in and out flows. Of the about 100 GtC upper-deep ocean carbon cycle, only 1.6 GtC is the negative accumulation in mass of the upper ocean layer, or 0.16% of the upper oceans, or 0.004% of the deep oceans.
While we don’t know any of the in/out flows of the atmosphere with sufficient accuracy, we do know the emissions with reasonable accuracy and the increase in the atmosphere with quite good accuracy. The difference between emissions and measured increase is the net (negative) accumulation in mass of all natural cycles together. We don’t need to know any of the individual flows or cycles to any accuracy, as only the net difference of all cycles together accumulates as mass in the atmosphere. The data show that in almost all years, the accumulation in mass of all natural cycles together is negative. And thus only the emissions give a real accumulation in mass.
To show the logical error in Dr Spencer’s example:

Let’s say the oceans are producing an extra 1 unit of CO2, mankind is producing 1 unit, and nature is absorbing an extra 1.5 units. Then we get the situation we have today, with CO2 rising at about 50% the rate of human emissions.

Which is right, but even in this example, the accumulation in mass in the atmosphere from the natural cycle is -0.5 units and that of the emissions is 1 unit. The same result as if you have an ocean which produces 90 units and absorbs 90.5 units, while the emissions still are 1 unit.
Even the same result if you have a crossover: the oceans produce 90 units and absorb 89 units, vegetation produces 60 units and absorbs 61.5 units and the emissions still are 1 unit.
In all cases, the natural cycles accumulate in mass -0.5 units and the emissions still are accumulating 1 unit in mass… The net result in all cases is +0.5 unit accumulating in mass in the atmosphere.
As you can see, the individual flows of a cycle have not the slightest influence on accumulation in mass, if the cycle is in balance. It is the unbalance that accumulates in mass (positive or negative). Calculations which only include one-way parts of the cycle lead to illogical conclusions.
The saturation of the oceans
Richard assumes that the oceans are far from saturated, because of the rapid changes in CO2 flows with temperature variations during the seasons. While we can’t speak of “saturation” here, the rapid changes prove that the CO2 flows are influenced by temperature, which is responsible for an immediate change in pCO2 (partial pressure of CO2) in the surface layer of the oceans. With steady pCO2 in the atmosphere, the pressure difference between ocean pCO2 and pCO2 of the atmosphere changes and thus the flows from one to the other. The limiting factor in all cases is the diffusion speed between water surface and atmosphere, which is rather low, but increases with wind speed.
The same is true for an increase of pCO2 in the atmosphere by the emissions: this leads to less outflow from the equatorial oceans and more inflow into the polar oceans and similar changes during the seasons. The current difference between pCO2 air/oceans is about 7 ppmv (7 microatm).
See for a lot more information on this topic:
That means that if the emissions should stop, next year there would be a drop of about 3 GtC out of the atmosphere, the second year about 2.4 GtC,… etc., until a new equilibrium is reached. The second cycle (upper-deep oceans) also remove CO2 from the upper oceans, which reduces the pCO2 of the upper oceans, which maintains to a certain extent the pCO2 difference air-upper oceans. Thus the second year, the drop will not be 2.4 GtC, but a little less than 3 GtC. Some more knowledgeable than me made a calculation, which resulted in an about 38 year half life time of the accumulation in mass caused by the emissions. This is governed by the pCO2 differences air/ocean.
What vegetation will do with decreasing CO2 levels is not easy to answer.
The half life time of the accumulation in mass of CO2 in the atmosphere is entirely different of the half life time of the accumulation in % in the atmosphere of the emissions, which is governed by the total carbon cycles between air and oceans/vegetation.
This was a long story, but it gives a good insight of the difference in opinion…
Ferdinand Engelbeen


Do it with ice core dated CO2, and also with some group of historical CO2 by chemical means. Use the same analysis as for the recent period

That’s what Beck has done. And the results are divergent. That’s where the science is.


Of total atmosphere only about 8% is from the emissions (65/800 GtC), and from the upper oceans only 3.5% (35/1000 GtC) is from human origin.

Just a clarification before further discussion (sorry if you have written it down).
Your numbers for CO2:
– human emissions since 1850: 300 GTc ending up in (1) + (2)
(1): 235 GT sequestered
(2): 65 GT in the atmosphere
– atmospheric increase since 1850 = +30% or 184 GT (615 GT in 1850-> 800 GT in 2006)
So if we stick to your numbers, that means the atmospheric CO2 increase since 1850 is
– 35% due to human CO2 emissions (65/184)
– 65% due to natural CO2 increase ((184-65)/184)
Do you mean that the CO2 increase is about 1 part manmade for 2 parts natural ?


I have noticed that when you but the ice core CO2 data into the air-measured CO2 there is a bigass divergence. You don’t need a PhD in snowballs to see that.
The air measures purport to start where the ice cores leave off. But is that raw or some funky adjustment to paste the ends together and make it look pretty? One thing is for sure: the air measure sure swoops off a heck of a lot faster than the ice cores!
Let’s look at the history. There was full war production in England from 1940, from Russia, from 1941, the US from 1942, and Germany, from 1943. (Not to mention Japan, which had been at war since 1937.) Not to mention blasting everything blastable including 100 cities (with several severe firestorms).
That’s a lot of damn CO2.
Then, after the war, there was a severe worldwide recession and retrenchment followed not until a few years later by what became the current industrial trend.
So where’s the wiggle in that suspiciously even graph, then? Do we have useful demographic data (numbers/types of factories, industrial output, coal/oil cinsumed, “car-mile” numbers, or whatever) from those days that can confirm these readings?
And what about the great Depression when a third to a half of industrial production simply–ceased? When gas was so dear that siphoning jokes were a very common form of humor?
So where’s Uncle Wiggles? Out to lunch?
Them there graphs is smooooooth. TOOOOOO smooth!

The d13C argument is not the sole argument that the accumulation in mass is caused by the emissions. The mass balance is the best argument.
Even if not all sinks are known to any accuracy, neither the partitioning between vegetation and oceans (one of them even may be a net source), we know with reasonable accuracy that all natural flows together form a net sink of average 3 GtC/yr (ad that is the difference between emissions and accumulation in mass in the atmosphere). This proves that the emissions are the sole cause of the accumulation in mass (except for a small temperature influence).
It would be different if some source was missing (if the accumulation in mass in the atmosphere was larger than the emissions).
But the d13C fate effectively exclude (deep) oceans as source of extra CO2. That is the main point.
Indeed what we measure in the atmosphere as d13C decrease is about 1/3th of what a direct calculation gives. This can be the result of
a) dilution of the atmospheric d13C decrease by the natural cycle oceans (0-4 per mil d13C) – atmosphere (-8 per mil) – oceans.
b) dilution of the atmospheric d13C decrease by an extra addition of ocean CO2
a) can be reached by an about 70 GtC carbon cycle (deep) oceans – air – oceans. Not that different of the 90 GtC (+/- 30%) found by Battle ea.
b) needs about 21 GtC extra inflow (without outflow) of deep ocean CO2, to reach the observed less decrease in d13C than calculated. But we don’t see a 28 GtC (oceans + emissions) increase in the atmosphere, only a 3 GtC increase, less than the emissions alone.
Thus there is no extra input of CO2 from the oceans.
About the ice cores, you should read the full article. That gives the reasons for the adjustments, which are quite small. The end of the ice core measurements is at the end ’70s, as that is the age of the ice at bubble closing depth. At the same depth, the CO2 age is about 10 years younger. Therefore we have no later ice core data, but we have firn data, which show a further increase of CO2 until current levels.
There is no difference between open bubble and closed bubble CO2 levels at closing depth, thus no diffusion problems seems to occur at least at closing depth.
Reactive decay is more a problem in the Greenland ice cores (volcanic deposits, more acid) than in Antarctica.
Three ice cores were drilled with different methods (wet and dry) at 0.5, 5, 16 km from the summit of Law Dome. The difference in CO2 levels between the ice cores is within 1.2 ppmv (one sigma). The South Pole trend is 0.8 ppmv lower than the average ice core trend.
The difference between ice core measurements and proxy data (like stomata data) is that with proper equipment and handling, the ice cores give a rather good sample of the real atmosphere of many years to milennia ago, while proxies need some translation between what you measure and ancient reality…


Could be, could be. Either what you say is true, or the measurements are highly questionable, or some other option, because so far as I can see ain’t no slow, steady curve in man’s use of CO2.
I know there may be the demographic data to dispute this notion, but from where I sit, looking at it writ large and crude, I can’t see it. I see seriuous ups and downs in man’s CO2 output.
Yeah, it’s a small percentage in the overall input/output matrix, but according to the the AGW advocates man IS the delta–a little less than half accumulating in the atmospheric sink and and rest winding up in the other two sinks, land and sea (a lot of that second half having routed through the atmosphere first).
If the AGW advocates are right, fluctuations in man’s output MUST change the curve (or why even bother cutting back?). They HAVE fluctuated (I contend). So why does the curve not reflect this?
Unless the “Rev” Watts is right? Wouldn’t be the first time, would it?
I’m surprised some historian or demographer has not pointed this out previously. (Heck, I’m surprised I never pointed this out previously.)


“A challenge to Roy Spencer, Richard Courtney, Stevo, Andrew and Steve Hemphill (and others): Demonstrate publically your skills in the scientific method by addressing the following —
Using known and established tenets of geochemistry and physical chemistry, describe how the delta-13-C data shown in Figure 4 of Bohm et al (2002) (conveniently provided by Mr. Engelbeen in his post as http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif ) does or does not support your theory that anthropogenically produced carbon (derived from fossil fuels) is NOT the cause of the increase in the content of atmospheric (and ocean) carbon dioxide shown by peer-reviewed data to have occurred in the last 1,000 years. ”
Demesure, I assure you that that is emphatically NOT what I said. I speculated that Oceans may MODULATE our emissions going into the atmosphere. It is not, as Ferdinand seems to believe, either, that I am saying that the oceans have a large effect that outweighs our input. I am simply stating that, again, the oceans are a sink, but not a constant one, and therefore that is the reason for the match between growth rate and temperature. I really wish my position wouldn’t be mischaracterized this way.

There is a lot of people which have problems to understand the difference between the two figures, you are by far not alone…
The 65 GtC is what is left of the original molecules of the emissions in % (accumulated in % of the atmosphere) of the atmosphere (which is diluted by the carbon cycles at a rate of 150/800 GtC per year).
The 184 GtC is what is accumulated in mass in the atmosphere, due to the emissions (which is diluted by the difference in in/outflows of the carbon cycles at a rate of 3/800 GtC per year).
Thus while the accumulation in mass is due to the total number of molecules added by the emissions, even during the year of emissions, about 20% (or more, depending of the distance between sources and sinks) is already exchanged with molecules of other origin. That alters the composition in %, but not the total mass…
To use the example of Segalstad: if you add a red colored small flow into a big tank where a lot of single in/outflows and cycles are in perfect balance, then the red color will be diluted in ratio with the total flows, while the total volume will increase with the total extra flow, independent of the rest of the flows and cycles…

Beck has made a graph of both the ice core data and the historical measurements:
See: http://www.biokurs.de/treibhaus/180CO2_supp.htm the graph is top left of the different graphs.
Warning: historical chemical data to be taken with caution. The 1942 about 100 ppmv (!) peak value is composed by a lot of data from places where the authors warn that they measured soil/plants/human emissions CO2… Even experiments set up to measure plant CO2 exchanges (rice fields 1941-1943, Misra, India) are included…

Evan Jones and Anthony,
You forget the difference in scale between the human additions and natural variations. The human additions are about 3.5 ppmv/yr, of which about 1.5 ppmv/yr accumulates in the atmosphere, the natural variations are within +/- 0.8 ppmv/yr, both to be observed at a scale of 380 ppmv.
Thus no wonder that the graph looks smooth, very smooth! Only extreme increases (like the 1998 El Niño) and extreme coolings (like the 1992 Pinatubo) can be easely observed.
The difference between the emissions and the natural variation is that the emissions caused the entire increase of 60 ppmv 1959-2004, while natural wobbles caused a temporarely change of a few ppmv, followed by normal temperatures (and CO2 increases, 1994) or even cooler periods (1999)…