For a another view on the CO2 issue, please see also the guest post by Tom Vonk: CO2 heats the atmosphere…a counter view -Anthony
Guest Post by Ferdinand Engelbeen
There have been hundreds of reactions to the previous post by Willis Eschenbach as he is convinced that humans are the cause of the past 150 years increase of CO2 in the atmosphere. For the (C)AGW theory, that is one of the cornerstones. If that fails, the whole theory fails.
This may be the main reason that many skeptics don’t like the idea that humans are the cause of the increase and try to demolish the connection between human emissions and the measured increase in the atmosphere with all means, some more scientific than others.
After several years of discussion on different discussion lists, skeptic and warmist alike, I have made a comprehensive web page where all arguments are put together: indeed near the full increase of CO2 in the atmosphere is caused by the human emissions. Only a small part might have been added by the (ocean) warming since the LIA. That doesn’t mean that the increase has a tremendous effect on the warming of the earth’s surface, as that is a completely different discussion. But of course, if the CO2 increase was mainly/completely natural, the discussion of the “A” in AGW wouldn’t be necessary. But it isn’t natural, as the mass balance proves beyond doubt and all other observations agree with. And all alternative explanations fail one or more observations. In the next parts I will touch other items like the process characteristics, the 13C and 14C/12C ratio, etc. Finally, I will touch some misconceptions about decay time of extra CO2, ice cores, historical CO2 measurements and stomata data.
The mass balance:
As the laws of conservation of mass rules: no carbon can be destroyed or generated. As there are no processes in the atmosphere which convert CO2 to something else, the law also holds for CO2, as long as it stays in the atmosphere. This means that the mass balance should be obeyed for all situations. In this case, the increase/decrease of the CO2 level in the atmosphere after a year (which only shows the end result of all exchanges, including the seasonal exchanges) must be:
dCO2(atm) = CO2(in1 + in2 + in3 +…) + CO2(em) – CO2(out1 + out2 + out3 +…)
The difference in the atmosphere after a year is the sum of all inflows, no matter how large they are, or how they changed over the years, plus the human emissions, minus the sum of all outflows, no matter how large they are, wherever they take place. Some rough indication of the flows involved is here in Figure 1 from NASA:
From all those flows very few are known to any accuracy. What is known with reasonable accuracy are the emissions, which are based on inventories of fossil fuel use by the finance departments (taxes!) of different countries and the very accurate measurements of the increase of CO2 in the atmosphere on a lot of places on earth, including Mauna Loa.
Thus in the above CO2 mass balance, we can replace some of the items with the real amounts (CO2 amounts expressed in gigaton carbon):
4 GtC = CO2(in1 + in2 + in3 +…) + 8 GtC – CO2(out1 + out2 + out3 +…)
Or rearranged:
CO2(in1 + in2 + in3 +…) – CO2(out1 + out2 + out3 +…) = – 4 GtC
Without any knowledge of any natural flow in or out of the atmosphere or changes in such flows, we know that the sum of all natural outflows is 4 GtC larger than the sum of all natural inflows. In other words, the net increase of the atmospheric CO2 content caused by all natural CO2 ins and outs together is negative. There is no net natural contribution to the observed increase, nature as a whole acts as a sink for CO2. Of course, a lot of CO2 is exchanged over the seasons, but at the end of the year, that doesn’t add anything to the total CO2 mass in the atmosphere. That only adds to the exchange rate of individual molecules: some 20% per year of all CO2 in the atmosphere is refreshed by the seasonal exchanges between atmosphere and oceans/vegetation. That can be seen in the above scheme: about 210 GtC CO2 is exchanged, but not all of that reaches the bulk of the atmosphere. Best guess (based on 13C/12C and oxygen exchanges) is that some 60 GtC is exchanged back and forth over the seasons between the atmosphere and vegetation and some 90 GtC is exchanged between the atmosphere and the oceans. These flows are countercurrent: warmer oceans release more CO2 in summer, while vegetation has its largest uptake in summer. In the NH, vegetation wins (more land), in the SH there is hardly any seasonal influence (more ocean). There is more influence near ground than at altitude and there is a NH-SH lag (which points to a NH source). See figure 2:
The net result of all these exchanges is some 4 GtC sink rate of the natural flows, which is variable: the variability of the natural sink capacity is mostly related to (ocean) temperature changes, but that has little influence on the trend itself, as most of the variability averages out over the years. Only a more permanent temperature increase/decrease should show a more permanent change in CO2 level. The Vostok ice core record shows that a temperature change of about 1°C gives a change in CO2 level of about 8 ppmv over very long term. That indicates an about 8 ppmv increase for the warming since the LIA, less than 10% of the observed increase.
As one can see in Fig. 3 below, there is a variability of +/- 1 ppmv (2 GtC) around the trend over the past 50 years, while the trend itself is about 55% of the emissions, currently around 2 ppmv (4 GtC) per year (land use changes not included, as these are far more uncertain, in that case the trend is about 45% of the emissions + land use changes).
We could end the whole discussion here, as humans have added about twice the amount of CO2 to the atmosphere as the observed increase over the past 150 years, the difference is absorbed by the oceans and/or vegetation. That is sufficient proof for the human origin of the increase, but there is more that points to the human cause… as will be shown in the following parts.
Please note that the RULES FOR THE DISCUSSION OF ATTRIBUTION OF THE CO2 RISE still apply!
Smokey says:
August 6, 2010 at 1:04 pm
My apologies for misunderstanding the “sharks” comment.
However, your CO2 mixing comment can’t end your argument with the line: “But that is for discussion on another part…”
No apologies needed!
I was trying to discuss Beck’s data, ice cores and stomata data as the last parts, therefore I wanted to stop that here as OT. But as that seems to pop up again and again, I need to comment that in next part, before other discussions, so that we may (dis)agree on what the data of ice cores, stomata and direct historical measurements are presenting. Thus no further comment now on Beck’s historical or stomata data…
Ferdinand,
Thank you for your reply and I do know these can be claimed as cause and effect.
There is still a problem that needs explaining with it because the ocean heat content at a set surface temperature maintains a balance between the atmospheric CO2 and the CO2 stored in ocean. This doesn’t matter if the CO2 is cause or effect of temperature. If CO2 levels increased as low as you mentioned with 8 ppmv with a 1c rise in ocean temperatures. (ice cores) Then readings from instrumental records should show a much lower increase in CO2 levels with the same energy heat content to remain in equilbrium, because the ocean is far from saturated. The extra CO2 added from humans would have a much larger sink into the oceans then shown with the same comparable 1c temperature increase. This is where the disagreement is between 1c/8ppmv and 1c/278ppmv.
F.E.,
Well heck, it’s no fun winning an argument that way!☺
“Simply, a wrong model is wrong so why discuss the details of it?”
Because that is the way science operates. If you want to show a model is flawed, you need to be able to explicitly identify the step in the derivation where the flaw is introduced (and I made every effort to make that as easy as possible for anyone who wanted to try – which is also an element of good scientific practice). If you recieved a review of a paper that said “a wrong model is wrong, so why discuss the details of it”, I’m sure you would be rather less than satisfied with it, and quite rightly so.
I almost laughed when I saw the above quote, however I then remembered there is nothing funny about skeptics marginalising themselves from an important debate by being unable to accept one of the few parts of AGW theory that is actually unequivocally supported by the observations.
Keep going Ferdinand, you are doing both sides of the debate a big favour; I only wish I had your patience to deal with the lack of acceptance of an idea that anyone capable of managing their own finances ought to be able to grasp, with such good grace. I salute you! ;o)
Ferdinand:
I have tried to explain your error to you in several ways, but you merely keep repeating it, most recently when at August 6, 2010 at 12:17 pm you write to me saying:
“Maybe you confuse the increase in mass with the origin of the molecules left in the atmosphere. Indeed the natural flows are much larger and much of the man-emitted CO2 is captured in the nearby tree or ocean in short time. But that has nothing to do with the origin of the increase in total mass, which still is entirely from the addition of man-made CO2, as long as the increase is less than the emissions.”
No. I do not “confuse” anything.
It does not follow that “the increase in total mass” is “entirely from the addition of man-made CO2, as long as the increase is less than the emissions”.
That only indicates that “the increase in total mass” is less than “the addition of man-made CO2”.
If the “the addition of man-made CO2” were directly responsible for the “the increase in total mass” then these two parameters would directly relate, but they do not. As I have repeatedly said (e.g. above at August 6, 2010 at 6:38 am):
“in some years almost the entire anthropogenic emission seems to be sequestered and in other years almost none of it”.
But this lack of a direct relationship between the two parameters does not prove “the addition of man-made CO2” is not responsible for the “the increase in total mass”. In fact it says absolutely nothing about whether or not the “the addition of man-made CO2” is or is not responsible for the “the increase in total mass” in whole or in part.
I can only repeat what I have repeatedly said (e.g. at August 6, 2010 at 12:17 pm) and hope that this time you will take note of it. I said there:
“You assume the natural system is invariate and is being disturbed by the anthropogenic emission. But the natural system is NOT invariate at any time scale (it even varies with the seasons). It consists of many interacting sub-systems that are each seeking to achieve equilibrium that none of them ever attains. The observed rise in atmospheric CO2 may be completely a result of the natural variations that may – or may not – be being significantly affected by the anthropogenic emission.”
Richard
Paul Birch: As it happens, only a relatively small fraction of the excess CO2 is composed of molecules directly resulting from anthropogenic emissions (IIRC it is only about 4% of the total reservoir). In know that it may sound counter-intuitive, but that is exactly what you would expect if the fluxes shown in Fig 1 are correct (which would mean the rise is purely anthropogenic). I briefly explained the reason for that in response to another poster earlier in the thread, however I can’t be bothered to revisit it as it is more complicated than the mass balance argument (basically set out the differential equations for a one-box carbon cycle model, plug in the figures, solve and see what you get). Alternatively, you could visit Ferdinand’s web site and read the explanation there.
Paul Birch says:
August 6, 2010 at 1:10 pm
If you really mean to say only that much of the actual CO2 currently in the atmosphere was put there by human activities then you may be right (though the mass-balance equation still doesn’t prove it, since it would be possible for all of the human-added molecules to have been removed by plants or solution into the sea and replaced by other molecules from those reservoirs). Even then, there is evidence that most CO2 is actually taken out of the atmosphere locally (by plants, rain, etc,), so only quite a small fraction may actually have been put there directly by man.
For the last 50+ years, some 120 ppmv CO2 was added by humans, some 60 ppmv still is in excess in the atmosphere. The other halve was aborbed by nature (both oceans and vegetation). The increase in the atmosphere is mostly not by the original molecules, as about 20% is exchanged with other reservoirs within a year. But still the entire excess is from human additions, no matter if the aCO2 molecule was captured in the next tree, but then it prevented the capture of a natural molecule instead, thus the total mass of CO2 increased anyway.
Dikran Marsupial:
At August 6, 2010 at 1:24 pm you quote from my post at August 6, 2010 at 12:54 pm where I said:
“Simply, a wrong model is wrong so why discuss the details of it?”
And you respond with:
“Because that is the way science operates. If you want to show a model is flawed, you need to be able to explicitly identify the step in the derivation where the flaw is introduced (and I made every effort to make that as easy as possible for anyone who wanted to try – which is also an element of good scientific practice).”
But I did “explicitly identify the step in the derivation where the flaw is introduced” in my post that you are answering. I said there:
“I have repeatedly explained that your model is based on the flawed assumption that the natural carbon cycle is invariate, and I have demonstratwed that the natural carbon cycle varies at all time scales.”
So, the identified “step” is at the initial stage of model definition. Your model describes a system that does not exist in reality. Hence, everything in your model is wrong because the model is based on a flawed premise.
As I said:
“Simply, a wrong model is wrong so why discuss the details of it?
(That would be like discussing the details of the dorsal fin on a model of a boat when the model resembles a fish.)”
And I do not know how I could have been more clear.
Richard
Dikran Marsupial says:
August 6, 2010 at 10:18 am
“Well as anthropogenic uptake is as close to nothing as to make no difference to the argument, we are in agreement then.”
It isn’t close to nothing. For example, one major source of CO2 emissions is quicklime production; but at later stages in its use a significant fraction of the CO2 is taken up again from the atmosphere (not all, because much is turned into silicates). Agriculture and forestry also take up considerable quantities (much of which, though not all, is subsequently released again). One needs to know the net figure, not merely the gross emissions.
““… so we would know that the natural environment is a net sink”
Dikran:“and hence cannot explain the observed rise.”
Paul: “Complete non sequitur.”
Dikran: “I don’t see how it can be a non-sequitur. How can the natural environment be responsible for the observed rise if the observations show it has been a net sink and hence taking up more carbon from the atmosphere each year than it emits? Seems a pretty reasonable step to me.”
Because the rise might have happened anyway!
Let me try an analogy. Imagine that you have a lake, connected through a pipe to a pond or drain. Water finds its own level, so the level in the drain is determined by the level of water in the lake. Now suppose you pour some the effluent water from your factory down the drain. Every year, as your factory ramps up its production, the amount of effluent increase. Lo and behold, you notice that over the years, the level of water in the drain seems to have been increasing. Even so, year on year, the drain is a net sink – more effluent goes down it to the lake than remains in the drain. Did your factory cause the rise? No. It just so happens that a succession of wet years has been gradually raising the level of the lake. The cause is wholly natural.
Dikran Marsupial says:
I was laughing so hard, I had to remind myself you are being serious.
Richard S Courtney says:
August 6, 2010 at 1:33 pm
It does not follow that “the increase in total mass” is “entirely from the addition of man-made CO2, as long as the increase is less than the emissions”.
That only indicates that “the increase in total mass” is less than “the addition of man-made CO2”.
Richard, as we both know, this doesn’t help at all. If you don’t accept that if the increase in the atmosphere is less than the emissions, that there is no net addition by nature, simply because nature is a net sink for CO2, then ends the discussion here.
This is such a simple math, as good as 4-8=-4, rock solid and accepted by anyone with a little common sense, that I still wonder how brilliant minds like you and Arthur Rörsch can think otherwise. But it be so. Meanwhile we are working on part 2.
If the “the addition of man-made CO2” were directly responsible for the “the increase in total mass” then these two parameters would directly relate, but they do not. As I have repeatedly said (e.g. above at August 6, 2010 at 6:38 am):
“in some years almost the entire anthropogenic emission seems to be sequestered and in other years almost none of it”.
But this lack of a direct relationship between the two parameters does not prove “the addition of man-made CO2” is not responsible for the “the increase in total mass”. In fact it says absolutely nothing about whether or not the “the addition of man-made CO2” is or is not responsible for the “the increase in total mass” in whole or in part.
This is of course an old discussion part and a non-argument: there is not the slightest reason that the derivative of the increase and the yearly emissions should relate (they do but not that good). The trend is directly related to the emissions, but the derivative of the trend is mainly influenced by temperature. That levels off in a few years.
That is a matter of signal-to-noise ratio: the signal in this case goes above the noise in 2-3 years. For e.g. the d13C decline the signal-to-noise ratio needs some 6-8 years before the signal emerges above the noise and sealevel gauges need some 25 years to (only statistically!) calculate the change in sealevel in between the huge noise that the tides show.
Ferdinand Engelbeen says:
August 6, 2010 at 12:24 pm
Paul Birch says:”…it is possible for the instantaneous concentration to be above or below the instantaneous equilibrium value (which is itself varying over time with changes in temperature, compositions of the seas, etc.).”
Ferdinand: “Sorry, but that is impossible: the moment that the instantaneous equilibrium is above the instantaneous concentration, the current sink would change in an instantaneous source…”
Not necessarily. I have already answered that point; you have simply ignored the crucial part of my answer. I give the full quote again:
“Sorry, but you’re wrong. In a simple system, what you say would be true; however, even then the amount by which the atmospheric concentration exceeded the equilibrium concentration could be arbitrarily small (small enough that for practical purposes we could ignore it). For a complex system, in which there are oscillations, lags, non-linear feedbacks, geographical non-uniformities, underdamping, etc., the conclusion is not valid; it is possible for the instantaneous concentration to be above or below the instantaneous equilibrium value (which is itself varying over time with changes in temperature, compositions of the seas, etc.).”
Anyone who has ever dealt with control systems, filters, transmission lines, feedback circuits or the like will know that what I say is true. Without a detailed understanding of the properties of the whole system, one cannot be sure that weird things like this won’t happen.
Dikran marsupial,
The AGW mantra is that human use of fossil fuels is causing an increase of CO2 in the atmosphere which in turn is raising the temperature.
The figures I quoted above, the implications of which Slioch perhaps intentionally ignored, show that human use of fossil fuels increased dramatically between 1980 and 2006 resulting in a 58% increase in CO2 emissions from their consumption. Yet the atmospheric CO2 increase over the same period barely changed at all continuing at roughly the same rate as it has since measurements began in 1959.
Now if the level of CO2 in the atmosphere was as sensitive to human use of fossil fuels as AGW insists why has that level not risen dramatically given the huge rise fossil fuel use?
Matt G says:
August 6, 2010 at 1:21 pm
Thank you for your reply and I do know these can be claimed as cause and effect.
There is still a problem that needs explaining with it because the ocean heat content at a set surface temperature maintains a balance between the atmospheric CO2 and the CO2 stored in ocean. This doesn’t matter if the CO2 is cause or effect of temperature. If CO2 levels increased as low as you mentioned with 8 ppmv with a 1c rise in ocean temperatures. (ice cores) Then readings from instrumental records should show a much lower increase in CO2 levels with the same energy heat content to remain in equilbrium, because the ocean is far from saturated. The extra CO2 added from humans would have a much larger sink into the oceans then shown with the same comparable 1c temperature increase. This is where the disagreement is between 1c/8ppmv and 1c/278ppmv.
Matt, you are right: the balance doesn’t fit. The main point is that the current ocean temperature says that the CO2 level should be around 290 ppmv (based on the 8 ppmv/C rate), but we measure 390 ppmv. The problem is that the oceans are slow absorbers of CO2. The excess we see nowadays only goes slowly into the (deep) oceans at a rate of about 2 GtC/year, while the increase in the atmosphere is about 4 GtC/year and the human emissions are at 8 GtC/year. Another part goes into vegetation.
The main problems in exchange rates are the slow transfer at the ocean-atmosphere border and the slow diffusion speed of CO2 in water. That is enhanced by wind speed (mixing). Thus while the excess is (relative) huge, the sink rate is low. That makes that the ppmv/C ratio currently doesn’t hold for absolute levels, but still is applicable for the fast variability around the trend.
Paul Birch says:
August 6, 2010 at 2:11 pm
Anyone who has ever dealt with control systems, filters, transmission lines, feedback circuits or the like will know that what I say is true. Without a detailed understanding of the properties of the whole system, one cannot be sure that weird things like this won’t happen.
In my former working life it happened that I was a process automation engineer. Thus I may say that I have some experience. Still, even in the most weird non-linear system, if the instantaneous equilibrium is above the instantaneous level, there would be instantly switching from any sink rate to a source rate. Except if you have a different definition of equilibrium?
But it happens that the whole CO2 cycle behaves as a simple, quite linear system for temperature changes, despite that a lot of underlying processes are far from linear.
Dave Andrews: I suspect the problem is that you are neglecting the 285 ppmv pre-industrial baseline in your calculations, (382-339)/(339-285) = 0.79 (ish). You would only expect the increase in emissions to correllate with the increase in the excess of CO2 over the pre-industrial baseline. The remaining difference is probably due to neglecting changes in land use, however I’d need to think about it. A plot of the data would probably be easier to see where the problem lies.
HTH
@ur momisugly Ferdinand Engelbeen
Originally, I asked, “I see you answered part of my questions with a response to another person. Thanks, but if…………………… “(see above)”…..is true then how did we get to 2000 ppmv CO2 100 million years ago?
You responded by saying, “Different times: different arrangement of the continents, different temperature/humidity, less calcite deposits,… The 8 ppmv/C only is for the last near million years, more ice age than interglacial, everything before that can’t be compared with current times…”
I replied, “Ok, you didn’t respond to my last query and I’m a bit more inebriated, so I hope you’ll forgive me for what some may perceive as abrasion. My abrupt manner should not be conceived as a personal attack……”
Oddly, I find myself in the same condition, once again. Weird. After expressing my displeasure with the dismissive manner in which you replied to me, you responded by stating, “Sorry that I was a little short in my answer: I have underestimated the number of comments I need to respond to. And yours was rather OT for the subject.”
OT? I thought we were discussing man’s contribution to the atmosphere’s CO2 content. My bad. Personally, I would consider conditions of the earth’s atmosphere, specifically CO2 content, without man, relevant to the discussion of man’s contribution to the earth’s atmosphere in terms of CO2. Sorry, I must have been confused for a second or two. (Mass balance)
While I’m discussing relevancy, I’m wondering how the shifting of land mass is in any way relevant to the CO2 content of the atmosphere, unless you are asserting the shifting itself causes a increase or reduction of CO2. (How you would quantitate it, is beyond me unless you rely on you mentioned above formula.) The earth continues to shift. How to you attribute the 1/2 increase to man? How much, more or less, are you attributing to land shift? Or do you consider this to be an unquantified constant? Perhaps we can nominally call it sh.. for shift?(Mass balance)
Are you sure we had less calcite deposits then? Or is that simply a plausible explanation to fit your belief? While I’m not from Missouri, “show me”. (Mass balance)
More to the point though, you said, “…everything before that can’t be compared with current times…” Yet, you, after the introduction, began with
“The mass balance: As the laws of conservation of mass rules: no carbon can be destroyed or generated.”
Yes, this is a widely accepted law of the elements. I’ve asked before, and, I’ll ask again, do you not hold these laws to have been true even then?
While I could continue the critique of your responses, an attempt a brevity is called for….
You said, “what is buried in oil, coal and chalk deposits was once a part of the oceans and atmosphere…”
That is probably true, yet beyond that assumption is the question “Where did the CO2 come from that was once part of the oceans and atmosphere?” Truly, CO2 is representative of past life and energy. Surely, you don’t believe the CO2 originated in the oceans and atmosphere, do you?
To the end of this conversation, Mr. Engelbeen, I find that you are a compelling, intelligent, and congenial individual. I thank you for the intellectual stimulation. It is much appreciated.
My final thoughts are as such: Mr. Engelbeen, your formula is wrong. You ought to recognize the error..
CO2(in1 + in2 + in3 +…) – CO2(out1 + out2 + out3 +…) = – 4 GtC
This formula only lends to the total depletion of CO2 from our atmosphere. I am not aware of any time in history, written or assumed, where this formula is properly applied. To my knowledge, this has never occurred with man or without. I don’t believe there is any historical evidence 100 mill or 1000 years that the formula could be correctly applied. Sir, you assume too much, or too little. This is reminiscent of a broken clock. It is correct 2 times a day. Your formula equates today. It never did before, and there is no compelling reason to presume it will tomorrow.
http://scienceandpublicpolicy.org/images/stories/papers/other/graph1.gif
That one doesn’t go back a million years, but what it does show is that the presumed constant -4 is incorrect. That being said, I do believe man has contributed to the total atmospheric CO2. To what end, we don’t know. We don’t know what mechanisms of the earth has kicked in or what stopped. We don’t know. What I know, it we can’t look to the future while ignoring the past. It is lunacy to attempt such an endeavor.
Thanks again,
James Sexton
Ferdinand:
I had to laugh at your post at August 6, 2010 at 1:33 pm.
In response to my having said:
“It does not follow that “the increase in total mass” is “entirely from the addition of man-made CO2, as long as the increase is less than the emissions”.
That only indicates that “the increase in total mass” is less than “the addition of man-made CO2”.”
You say:
“Richard, as we both know, this doesn’t help at all. If you don’t accept that if the increase in the atmosphere is less than the emissions, that there is no net addition by nature, simply because nature is a net sink for CO2, then ends the discussion here.”
Well, it certainly does not help your case at all.
Your argument certainly is, as you say, “simple math”. Indeed, it is so “simple” that it is wrong because it makes false assumptions then calculates the results of those assumptions.
Do I really need to yet again explain why your assumptions are plain wrong?
Please read what I have repeatedly written – in as many ways as I could – above.
Then, in response to my having pointed out that:
“If the “the addition of man-made CO2” were directly responsible for the “the increase in total mass” then these two parameters would directly relate, but they do not. As I have repeatedly said (e.g. above at August 6, 2010 at 6:38 am):
“in some years almost the entire anthropogenic emission seems to be sequestered and in other years almost none of it”.
But this lack of a direct relationship between the two parameters does not prove “the addition of man-made CO2” is not responsible for the “the increase in total mass”. In fact it says absolutely nothing about whether or not the “the addition of man-made CO2” is or is not responsible for the “the increase in total mass” in whole or in part.”
You responded tothat with a load of arm waving about “signal-to-noise ratio” that is pure twaddle.
The fact is that the seasonal variation is much more than the anthropogenic emission in each year. And the increase in atmospheric CO2 for each year is the residual of the seasonal variation. Your mass balance calculations assume the residual is induced by the anthropogenic emission, so – if that is the case – then please explain why in some years almost the entire anthropogenic emission seems to be sequestered and in other years almost none of it.
This is not – as you assert – a “non-argument”. It is an empirical fact that requires an explanation if your mass balance is to be remotely plausible.
And you do not explain it with your assertions that
“The trend is directly related to the emissions, but the derivative of the trend is mainly influenced by temperature”.
Those assertions are what is commonly called an excuse.
Is the trend directly related to the emissions? That is what you need to prove, not assert.
And is the derivative of the trend mainly influenced by temperature? If so, then why is the trend not mainly influenced by the temperature?
Your assertions may be right (or wrong) but if they are right then please provide some empirical evidence to substantiate them. Arm waving is not evidence.
Richard
Dave Andrews: I forgot to mention that the net environmental sink will also have strengthened over that period (see figure 3 of the OP).
Dave Andrews says:
August 6, 2010 at 2:23 pm
Dikran marsupial,
The figures I quoted above, the implications of which Slioch perhaps intentionally ignored, show that human use of fossil fuels increased dramatically between 1980 and 2006 resulting in a 58% increase in CO2 emissions from their consumption. Yet the atmospheric CO2 increase over the same period barely changed at all continuing at roughly the same rate as it has since measurements began in 1959.
Have a better look at figure 3 in the introduction: The rate of emissions in the period 1960-2004 more than doubled. But so did the increase rate of the atmosphere too, be it more variable. The yearly increase, not the total trend, is roughly related to the yearly emissions. The trend itself is directly related to the accumulated emissions.
Still working the bugs out of my grammar check program.
Paul Birch says:
August 6, 2010 at 1:54 pm
Lo and behold, you notice that over the years, the level of water in the drain seems to have been increasing. Even so, year on year, the drain is a net sink – more effluent goes down it to the lake than remains in the drain. Did your factory cause the rise? No. It just so happens that a succession of wet years has been gradually raising the level of the lake. The cause is wholly natural.
If the increase in the drain is less than what can be calculated from the increased production outflow, then there can’t be a natural increase in the lake. If there was a natural increase in the lake, the increase in the drain would be larger than calculated from the increased production.
Ferdinand
Sorry to drop a small fly in the ointment at this late stage, but, for the sake of completeness, may I return to your previous statement, with which I previously agreed, viz.: “As long as the increase of CO2 in the atmosphere is less than the human emissions, nature doesn’t add any extra CO2 (as mass, not as individual molecules) to the atmosphere.
It is that simple…”
Yes. But, not quite. As I mentioned earlier, volcanoes contribute about 1% as much CO2 to the atmosphere as human emissions [though actually much of this CO2 is in sub-sea emissions and therefore doesn’t get into the atmosphere, but I’ll stick to 1% for brevity] . Like human emissions from burning fossil fuels, the CO2 from volcanoes is “new”: that is, it consists of CO2 (or carbon) that has not been involved in the short-term carbon cycle (ie that which consists of interactions between the atmosphere, oceans and biosphere) for a very long time. Therefore, volcanic CO2 should be added to anthropogenic CO2 from burning fossil fuels when calculating the increase in atmospheric CO2. As you mentioned in your original article, about 55% of the CO2 emitted by humans is absorbed by the oceans and terrestrial systems, leaving about 45% in the atmosphere (my figures give 40%, but no matter), and this figure appears to be fairly constant. If total anthropogenic + volcanic atmospheric CO2 emissions increase, then the amount of CO2 remaining in the atmosphere increases proportionately.
It follows, therefore, that about 1% of the annual increase in CO2 in the atmosphere is due to volcanic activity, and the above statement is not quite correct: nature does add CO2 as mass to the atmosphere because of volcanoes. If volcanoes had not emitted any CO2 for the last hundred years, then the amount of CO2 in the atmosphere would be less than it currently is, by a small amount.
James Sexton says:
August 6, 2010 at 2:49 pm
While I’m discussing relevancy, I’m wondering how the shifting of land mass is in any way relevant to the CO2 content of the atmosphere, unless you are asserting the shifting itself causes a increase or reduction of CO2.
If most landmass is around the poles, in a cold climate, there is ample room for vegetation (see Antarctica!). If most is around the equator, that gives abundant vegetation. That influences CO2 levels and sequestering (coal formation).
Much of the current chalk deposits are from the Cretaceous period. That has influenced the CO2 levels, but still no carbon was destroyed or formed, the conservation of mass did hold, only there was an exchange of carbon between different reservoirs.
The bulk of all carbon still is in the deep oceans, but I have no idea how it was formed during the formation of the earth.
For the last few million years, the geological changes are too slow to have much impact on CO2 levels, except temporarely for huge volcanic eruptions. The climatological impacts are far huger: ice ages and interglacials. Thus the geological changes are not included.
About my formula: that is only for the past 50 years, as that is the period we have with very accurate CO2 measurements. The -4 GtC is not fixed, but variable: in 1960 it was -1 GtC (0.5 ppmv), in 2006 it is about -4 GtC and we have a year-by-year natural variability. See the green part of Fig. 3 in the introduction.
There is no fear that the formula will deplete the atmosphere from CO2, as humans add about twice the amount that is removed.
Slioch: volcanic emissions are just part of “environmental emissions” for the purposes of the mass balance argument (as “environmental emissions” is basically all emissions that are not anthropogenic). Figure 3 shows that environmental uptake is large enough to absorb ALL environmental emissions (including that from volcanos) and enough left over to absorb about half of anthropogenic emissions as well, so if volcanos are viewed as being part of the natural environment, they are not contributing to the rise (as other changes in the natural environment are compensating for them).
It is true that the volcanic CO2 was previously geologically sequestered, but volcanic emissions have been going on for thousands of years without causing a noticable rise in atmospheric CO2.