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!
What is fascinating is just how terrified many people here seem to be about accepting Ferdinand’s simple argument. Simple arguments are often correct, because they ignore the irrelevant detail.
People who want to confuse will focus on the details (i.e. to use an apt saying, “baffle you with bull****”)
Slioch says:
August 11, 2010 at 4:49 am
“Well, actually, my bald rejection was in response to your bald assertion, so I think we are about quits on that score.”
No, I did actually attempt to explain the flaw, the fact that you did not accept the explanation does not make it a bald assertion. Your reply on the other hand was merely contradiction. There is too much rhetoric here, which is unhelpful (my Monty Python quote was intended as good natured levity, sincere appologies if it wasn’t perceived that way.
“But to return to the matter of substance. Can the mass balance equation on its own determine whether human emissions are responsible for the rise in atmospheric CO2, as you maintain, or does it require additional information from the wider environment, as I maintain?”
No additional information is required. If the natural environment and man made positive contributions to the observed rise, the observed rise would necessarily be higher than anthropogenic emissions, provided the carbon cycle is a closed system (i.e. no carbon spontaneously appears or dissapears or enters or leaves Eath). As I have pointed out, conservation of mass implies a closed system. Hence no other assumptions are required.
“Or is the correct conclusion that, “humans have added about twice the amount of CO2 to the atmosphere as the observed increase over the past 150 years, which means that the human emissions are more than able to explain the increase in atmospheric CO2″, as I maintain?”
No, you don’t need the mass balance argument to show that, the data tell you that directly, as shown by the red and blue lines in fig. 3. The mass balance argument gives the green line, which is the one that establishes that the natural environment is a net sink and hence has opposed the rise.
“This may seem a trivial hair-splitting point to some (not yourself I think), but it is not. We both agree (I assume) that it is important for people to accept the human causality behind the recent rise in atmospheric CO2. It is therefore important to present an argument that does not contain a logical flaw. I believe your mass balance argument does contain such a flaw.”
I agree that it is important; your definition is obviously true without the mass balance argument. The mass balance argument assumes conservation of mass, and it is that that allows a tightening of definitions from the one that you have given, to the one that Ferdinand has given (and I have tagged along in his wake ;o)
“Here is, I believe, proof of that logical flaw:We start with the same bits of information as previously:
8Gts/year human emissions of CO2 to the atmosphere
4Gts/year net gain in atmospheric CO2
80Gts/year emission of CO2 from a volcano “somewhere in the Pacific”.
Dikran doesn’t know about the volcano, he uses the mass balance equation thus:
4 GtC = CO2(in1 + in2 + in3 +…) + 8 GtC[HE] – CO2(out1 + out2 + out3 +…)
(I’ve added a [HE] (Human Emissions) label for clarity)
which is certainly valid, and he concludes from it that all factors other than human emissions are acting together as a net sink, which also valid. Therefore, according to Dikran/Ferdinand that is sufficient proof for the human origin of the increase.”
Just one question, if you agree that “all other factors” (what I have been calling the “natural environment”) is a net sink, how can it be contributing in any way to the rise?
“Narkid, on the other hand (being a contrary kind of guy), doesn’t know about human emissions,”
obviously a bit backward as well ;o)
“but he does know about the volcano. So he write this mass balance equation:
4 GtC = CO2(in1 + in2 + in3 +…) + 80 GtC[Vol] – CO2(out1 + out2 + out3 +…)
which is certainly valid, and he concludes from it that all factors other than the volcano are acting together as a net sink, which is also valid. Therefore, according to Narkid that is sufficient proof for the volcanic origin of the increase.
So, Dikran “proves” that human emissions are uniquely responsible for the increase.
and Narkid “proves” that the volcano is uniquely responsible for the increase.
Both “proofs” are equally valid (or invalid). But it is impossible for one event to be caused by two causes: it is impossible to claim that the rise in atmospheric CO2 is uniquely caused by human emissions and also to claim that it is uniquely caused by the volcano.”
The only possibility therefore is that neither Dikran’s nor Narkid’s proofs are valid. ”
I do now see where the difficulty lies, and it is caused by the arbitrary splitting of the natural environment into the volcano and every thing in the environment but the volcano. Let A be the net anthropogenic flux, B be the net volcanic flux, C is the net flux of the natural environment except the volcano
Dikran proves that A is positive and that (B + C) is negative
Nirkad proves that B is positive and that (A + C) is negative
There is no contradiction there, it just means that C is negative and of larger magnitude than A or B. Both proofs are valid.
Dikran has proved that the natural environment including the volcano is a net sink.
Nirkad has proved that the natural environment except the volcano plus anthropogenic emissions is a net sink.
Both are true. I think the question is one of change (as Arthur Rorche suggests) if the volcanos out put were changing, then yes it could be said to be a cause of CO2 in the sense that if it became extinct then atmospheric levels would plummet because other elements of the natural environment had uptake that was more than compensating for its emissions. We still though wouldn’t see a rise if not for anthropogenic emissions (as B + C is still negative).
Essentially there is a meaningfull distinction between us versus the natural environment, but not between a volcano and (us plus the rest of the environment). Both proofs are correct, but perhaps it is not the case that both questions are meaningful. Is it meaningful to pick out one element of the natural environment just because it happens to be a net source and ignore the fact that what remains is an even larger net sink?
Good insightful comments, I have enjoyed thinking about them.
Arthur Rörsch wrote:
“I admit that my former calculation
“Thus the Fa consists for 35 % of the anthropogenic emission = 1.225 GtC/y
Fa consists for 65 % of the other source dFin = 2.275 GtC/y (That is not a negative contribution. It is a substantial one)”
is wrong. I hope to do better soon by falling back on former calculations which indicated that theoretically the anthropogenic component must be (even) much less. (6 %). And that figure (even) does not match with observations in the ocean mixing layer (2%).”
I gave an example here that demonstrates that your existing method gives contributions that are too small. If you have a method that makes them even smaller, then my business proposal would be even more profitable (for me that is ;o). I would very much appreciate your thoughts on that post, and especially on the proposed method of assigning contributions that unlike your previous one takes uptake into account as well as emissions.
Dikran Marsupial says:
August 10, 2010 at 4:37 pm
“I also disagree with your definition of causal, mine is based on what actually did happen, not what might have happened. The mass balance argument tells you what actually DID happen, which is that for the last fifty years the natural environment has taken in more CO2 than it emitted and therefore has not contributed anything at all to the rise – nothing. ”
Yes, “what actually happened” is a different and acceptable definition of causality – which despite repeated questioning you previously refused to confirm when I specifically asked you what “the CO2 increase is man made” meant to you. Your “what actually happened” causality implies my meaning number 2, “most of the extra CO2 molecules in the air are the ones put there by man”. Indeed, to say that the natural environment has contributed nothing to the rise requires that “all of the extra CO2 molecules in the air were put there by man”. And that simply isn’t true. What has actually happened is that most of the extra CO2 in the air has been contributed by various natural sources – outgassing from the ocean, respiration of plants and animals, volcanos, lake overturns and so forth. What has actually happened is that practically all of the CO2 emitted into the atmosphere by man has been taken up by the various natural sinks. By contrast, the mass balance is a way of skipping over what has actually happened to a simplified model in which most of what actually happened is ignored and only a single synthetic figure that you consider significant is permitted to be considered. There’s nothing wrong in itself with paring away unnecessary details to create a scientific model, but if you do then the causality you need to employ has to be of the “what would have happened” variety.
Slioch says:
August 11, 2010 at 4:49 am
4 GtC = CO2(in1 + in2 + in3 +…) + 80 GtC[Vol] – CO2(out1 + out2 + out3 +…)
which is certainly valid, and he concludes from it that all factors other than the volcano are acting together as a net sink, which is also valid. Therefore, according to Narkid that is sufficient proof for the volcanic origin of the increase.
Indeed, this is valid if you want to compare the volcano with the rest of the natural world + human emissions, then it is a valid comparison. If the increase in the atmosphere were lower than the volcanic emissions, we might be quite certain that it is the sole source of the increase, as the rest of the natural world + human emissions were a net sink. Regardless of the height of the human emissions.
But that is the danger of mixing natural and human emissions/sinks together: you can have any result if you mix human emissions with natural emissions or natural sinks together. That doesn’t tell us anything about the effect of the human emissions and what the natural world does (absorbing all emissions of the volcano + the rest of the natural emissions + a part of the human emissions)
In the current case, we are interested in the effect of human emissions and nothing else, therefore one need to look at the net effect of all natural inputs and outputs together, including the 80 GtC volcano: if the result of the measured increase is less than the emissions, the input of the 80 GtC volcano (or even the CO2 pipeline from Zorg) is more than compensated by natural sinks, whatever that be…
That does tell us everything we need to know about what the human emissions + the natural world does (absorbing all emissions of the volcano + the rest of the natural emissions + a part of the human emissions)
Further, indeed there are more indications that natural causes are not responsible.
John Brookes says:
August 11, 2010 at 6:26 am
What is fascinating is just how terrified many people here seem to be about accepting Ferdinand’s simple argument. Simple arguments are often correct, because they ignore the irrelevant detail.
People who want to confuse will focus on the details (i.e. to use an apt saying, “baffle you with bull****”)
I had never heard of Georgists before, I begin to wonder who are the Georgists here…
Paul Birch says:
August 11, 2010 at 8:35 am
What has actually happened is that most of the extra CO2 in the air has been contributed by various natural sources – outgassing from the ocean, respiration of plants and animals, volcanos, lake overturns and so forth. What has actually happened is that practically all of the CO2 emitted into the atmosphere by man has been taken up by the various natural sinks.
This is a typical confusion between the origin of the CO2 molecules in the atmosphere and the origin of the increase of the total mass of CO2 in the atmosphere.
Indeed, which CO2 molecules are added or removed from the atmosphere is a matter of exchange rates or throughput (some 150 GtC back and forth between oceans/vegetation and atmosphere) giving the residence time, but the increase in mass of CO2 is only 4 GtC, the difference between all input fluxes (including 8 GtC from humans) and all output fluxes. Both have nothing to do with each other.
Arthur Rörsch says:
August 11, 2010 at 4:49 am
Does anybody has a figure for the increased ‘greening’ of the planet? I remember that Ahlbeck once showed that this increase coincides with the raise of CO2 in the atmosphere and temperature rise over the last decades, even with the annual fluctuations. According to the scheme in your original post, the green + soil reservoir is pretty large compared to that of the atmosphere and the ocean mixing layer.
The greening of the earth (including the longer term increase of more permanent carbon sequestering from plants) is quite moderate, 1.0-1.4 GtC/year, based on O2 and d13C changes. See:
http://www.sciencemag.org/cgi/content/abstract/287/5462/2467 (full article behind a paywall) and
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf (free)
Other estimates show that vegetation was more a source in the first century of human emissions, but changed into a net sink around 1950. See the pages of Pieter Tans at:
http://esrl.noaa.gov/gmd/co2conference/pdfs/tans.pdf page 5-10.
Paul Birch wrote:
“Your “what actually happened” causality implies my meaning number 2, “most of the extra CO2 molecules in the air are the ones put there by man”. Indeed, to say that the natural environment has contributed nothing to the rise requires that “all of the extra CO2 molecules in the air were put there by man”.”
This is not correct. Consider two boys who share a sweet jar. One boy, “Bob”, puts in 8 humbugs a month and never takes out any sweets. The other, “Jack”, puts in 90 gobstoppers a month, but takes out 94 sweets at random. After a year you will find the jar contains 4*12 = 48 more sweets that it did at the start, and you will find that the majority of the excess will be comprised of gobstoppers not humbugs. This is the case even though it is very obviously Bob that is the cause of the increase in the number of sweets in the jar as Jack has been taking out more sweets than he put in.
The reason is because the sweets have a short residence time (because of Jack) but a long adjustment time (because the change in the level of sweets depends on the difference between total input and total output fluxes, not their magnitides). This is non-obvious and others have made this mistake before. I wrote a couple of computer simulations to verify that the very similar argument on Ferdinand’s excellent website is correct.
BTW defining causality in terms of what might have happened. Driving home from work today it ocurred to me “Yes officer, I did drive into the car in front of me, but I didn’t cause the accident becuase if I hadn’t run into it the car behind me might have done”. Do you think I should file that one away in case I ever have an RTA? Note you don’t *know* what would have happened if not for anthropogenic emissions, so you are also talking about what might have happened, not what would have happened.
Thanks Ferdinand,
I will study the references later.
I am now working on a general formulation of the differences of views on the meaning of the global overall balance. On principles. We may quantify later.
Yours
Arthur
Dikran Marsupial:
August 11, 2010 at 7:44 am
Hi,
I think you are still not seeing the problem, (which is concerned with what Dikran and Narkid claim to prove). Have another look at what I said Dikran and Narkad were claiming to have proved: they are not how you have described them with your A, B, C equations.
But maybe your definitions A, B and C (which are otherwise perfectly valid) provide a way of explaining it more clearly. You state:
” Let A be the net anthropogenic flux, B be the net volcanic flux, C is the net flux of the natural environment except the volcano
Dikran proves that A is positive and that (B + C) is negative
Nirkad proves that B is positive and that (A + C) is negative
There is no contradiction there, it just means that C is negative and of larger magnitude than A or B. Both proofs are valid.”
Indeed, there is no contradiction there. Trouble is, that was not what I was referring to as their claimed “proofs”, as I stated above.
However, we can go further with the use of A, B and C because we know:
A+B+C = 4 so since A = +8 and B = +80 then C = -84 (I’ll leave out the units for clarity). So, lets use those figures.
What I referred to as the claimed proofs are as follows:
Dikran/Ferdinand are claiming that because the sum of 8 + (80 -84) comes to +4, then that positive sum, +4, is sufficient proof for the human origin of the increase. In other words they are claiming that the cause of the +4 sum is SOLELY the +8 net human contribution.
Narkid, on the other hand, is claiming that because the sum of 80 + (8 – 84) = +4 then that positive sum, +4, is sufficient proof for the volcano origin of the increase. In other words he is claiming that the cause of the +4 sum is SOLELY the +80 net volcano contribution.
The two claims cannot be simultaneously correct. Since , both have equal logical status, it is not possible for one to be correct whilst the other is wrong. Therefore, both are false.
The only way for Dikran/Ferdinand can demonstrate that indeed the human emissions are the cause of the rise in atmospheric CO2 is to go beyond the mass balance equation and obtain information from the general environment: in particular, they need to show that the volcano (or indeed any other putative net source of CO2 to the atmosphere) does not exist , and that therefore its net contribution to the atmosphere is zero (ie. B = 0 ). Having done so, they can return to the A, B, and C equation and find that:
A + B + C = 4 as before, but now A = 8 (as before) and B = 0, so C = -4.
Hence, Narkid’s claim is now based on the sum of 0 + (8 – 4) = +4 . In other words he is claiming that the cause of the +4 sum is SOLELY the 0 (zero) net volcano contribution!
Claiming a cause from zero input is self-evidently false: the claim falls on its own, not because it conflicts with Dikran/Ferdinand’s claim, and it thereby leaves Dikran/Ferdinand’s claim triumphant (though changed to 8 + (0-4) = +4, in which also there can now clearly be no objection to claiming that the +8 human contribution is UNIQUELY responsible for the +4 increase in atmospheric CO2).
BUT, remember, in order to establish Dikran/Ferdinand’s claim as valid they had to go out of the mass balance equation and gather information from the general environment: the mass balance equation by itself was not sufficient.
Slioch, having thought about it some more. Dikran’s version of the mass balance equation correctly establishes that the environment (as a whole) is a net sink of carbon from the atmosphere. However, it does not prove that the natural environment does not contain components that are net sources, or that some of those net sources are not larger than anthropogenic emissions, which is why Narkid’s version is also correct. Neither of these are contentious observations, if the natural environment contains components that are net sources (perhaps large) then the mass balance argument tells us there must also be components that must be (even larger) net sources that are compensating.
So the mass balance argument does establish that the natural environment as a whole is a net sink. That establishes that the environment, considered as a whole, is not a cause of the rise, I don’t see the fact it has a component that is a net source makes a difference, as this neglects the fact it also has components that are an even bigger sink, but both components define what the environment is actually doing.
What is your view?
Slioch, do you agree that Dikran’s version of the mass balance argument demonstrates that the natural environment as a whole is a net sink?
Dear Dikran,
I am not responding to your posts, because I am behind reading all the new posts. Besides one, the metaphor of the banking account. I do not like considering these kind of methaphors. They always have their limitations. I restrict myself to the real accounting of the CO2 balance. May be you forgot in your metaphor there may be sombody robbing your account, or that an anonymous maffia member deposited an amount for ‘favours’.
I am thinking over my analysis of the controversies on the CO2 accountancy for another day.
Ferdinand Engelbeen says:
August 11, 2010 at 9:18 am
Paul Birch says: “What has actually happened is that most of the extra CO2 in the air has been contributed by various natural sources – outgassing from the ocean, respiration of plants and animals, volcanos, lake overturns and so forth. What has actually happened is that practically all of the CO2 emitted into the atmosphere by man has been taken up by the various natural sinks. ”
Ferdinand says: “This is a typical confusion between the origin of the CO2 molecules in the atmosphere and the origin of the increase of the total mass of CO2 in the atmosphere.”
I am not confusing anything (though you and Dikram are). I am making a plain statement of fact – of what actually happened. Do you deny those facts? If the meaning of “the CO2 increase is man made” is to be found in “what actually happened”, as Dikram insists, then what actually happened is that practically all of the extra CO2 came from natural sources. What would have happened to the total is quite a different question. You both seem incapable of grasping the difference, because you keep sliding illegitimately from one to the other.
“Indeed, which CO2 molecules are added or removed from the atmosphere is a matter of exchange rates or throughput (some 150 GtC back and forth between oceans/vegetation and atmosphere) giving the residence time, but the increase in mass of CO2 is only 4 GtC, the difference between all input fluxes (including 8 GtC from humans) and all output fluxes. Both have nothing to do with each other.”
They are of course not identical, as I have persistently tried to get you to realise, but they are far from unrelated. The physical processes decribing what actually happens throughout the entire system are indeed those of addition, removal, diffusion, and metamorphosis of CO2 molecules. The mass balance is a synthetic summary of just one aspect of those processes.
Arthur Rörsch says:
August 11, 2010 at 4:49 am
But the fact remains that a tiny fraction of extra inflow (8/150) seems to disturb the system in such a way, that (also) non anthropogenic CO2 is accumulating strongly. That makes many people think by intuition that the extra inflow can not be the only cause of accumulation and do search for other causes of the unbalance, with many different in and outflows in the system and reservoirs that store the CO2 above the deep sea.
Arthur, what you are mixing up is the origin of the molecules with the origin of the increase in mass. Many before you have been confused by this, including Paul Birch as it seems now.
The emissions add to the overall increase, as these are one-way. The natural inflows don’t add to the increase, as long as the natural outflows are larger than the natural inflows. That is the case now. In this case, the absolute height or the variability in height of any individual inflow or sum of all inflows is of no importance, as the net result still is negative: more outflow than inflow, thus a net sink, not a source.
Your own table shows that: whatever the inflow, the outflow must counter that with 3.5 GtC more, to obey the (negative) mass balance of the year 2000.
Thus any increase in natural inflow in some year either must be moderate (in total less than the emissions) or does require an increase in outflow to get the calculated sink rate of that year.
A complete different point is the effect of an increased inflow on the type of molecules in the atmosphere: the current anthro inflow is about 8 GtC. That gets into 800 GtC of the atmosphere, or a first-year increase of anthro CO2 with 1%. But that is diluted already in the first year by the 150/800 GtC throughput (that is 150 GtC input and 153.5 GtC output) or about 20% dilution. Together with the long-term additions of anthro CO2, and the year-by-year dilution, we only have 6-9% CO2 of anthro origin in the atmosphere, even if the full increase with 30% is attributable to the anthro emissions.
The 150 GtC natural inflow is not an “extra” inflow, it is only a part of the throughput, where the outputs are even somewhat larger than the inputs, thus not contributing to the increase, only contributing to the circulation of carbon through the atmosphere. If the 150 GtC throughput increases (but the natural mass balance still is the same, negative), that does affect the dilution of anthro CO2, but doesn’t affect the increase, which still is entirely from the emissions.
Please, have a look at the very clear demonstration of what is wrong with your reasoning by Dikran, August 10, 2010 at 7:34 am
Dikran Marsupial says:
August 11, 2010 at 10:53 am
Paul Birch wrote: “Your “what actually happened” causality implies my meaning number 2, “most of the extra CO2 molecules in the air are the ones put there by man”. Indeed, to say that the natural environment has contributed nothing to the rise requires that “all of the extra CO2 molecules in the air were put there by man”.”
Dikran said: “This is not correct. ”
It is correct. What actually happened is that natural sources supplied most of the extra CO2 actually in the atmosphere. You are trying to slither out of that conclusion by sneaking in a bit of what would have happened instead. You must stick with one or the other. Not both.
“Consider two boys who share a sweet jar. One boy, “Bob”, puts in 8 humbugs a month and never takes out any sweets. The other, “Jack”, puts in 90 gobstoppers a month, but takes out 94 sweets at random. After a year you will find the jar contains 4*12 = 48 more sweets that it did at the start, and you will find that the majority of the excess will be comprised of gobstoppers not humbugs. This is the case even though it is very obviously Bob that is the cause of the increase in the number of sweets in the jar as Jack has been taking out more sweets than he put in.”
Both Bob and Jack have in fact increased the number of sweets in the jar. Both have caused an increase in the number of sweets in the jar. (Most of the extra sweets in the jar have in fact been put there by Jack). These facts are not affected by the additional fact that Jack has also been responsible for decreasing the number of sweets in the jar. If you wish to go further than that – to give causative meaning to what happened – you have to ask what would have happened or why it happened. And this is just what (from the facts given) we don’t know. Perhaps the reason Bob put the sweets in, or failed to take any out, was because Jack stuck a gun in his face and threatened him. Perhaps Jack only took some sweets out because
Bob put sweets in. And so forth.
“BTW defining causality in terms of what might have happened. Driving home from work today it ocurred to me “Yes officer, I did drive into the car in front of me, but I didn’t cause the accident becuase if I hadn’t run into it the car behind me might have done”. Do you think I should file that one away in case I ever have an RTA? Note you don’t *know* what would have happened if not for anthropogenic emissions, so you are also talking about what might have happened, not what would have happened.”
The meaning of “it might be that X would have happened” is not the same as “X might have happened”. The former implies that, if conditions in the past were Y (but I don’t know whether they were), their consequence would have been X. The latter is less restrictive and includes statements like, given the past conditions Y, X was one possible outcome..
In your car crash, the relevant response might be “Yes, I ran into the car in front, but I didn’t cause the accident, because the car in front reversed into me”. Or , “the car behind ran into me first”. You only caused the accident if there was something you could have done to prevent it. And even then, others may share the responsibility. So if, for example, the car behind was going to run into the car in front anyway, it wasn’t your fault. That’s what you’d say on your insurance claim, and if the company believed you, they’d pay up without docking your no-claims bonus.
Dikran Marsupial
August 11, 2010 at 11:14 am
There is no problem with claiming that the the natural environment as a whole is a net sink: that indubitably is what the mass balance equation establishes (given the human emissions of +8Gts/year, and net atmospheric gain of +4Gts per year, or thereabouts). I agree entirely with your first paragraph.
But what mass balance equation cannot establish from those two bits of information alone (plus conservation of mass) and does not allow us to claim is “proof for the human origin of the increase” as claimed in the original article. That requires a demonstration that there are not things like my mythical volcano in the Pacific, and the mass balance equation alone provide no information in that regard: that requires environmental information from outwith the mass balance equation.
What it boils down to is that there (unfortunately) is not a simple mathematical proof that the recent rise in CO2 is due to human actions alone. In order to establish that the rise in atmospheric CO2 is overwhelmingly due to human actions (which is what I consider the evidence nonetheless demonstrates) we require to use the same messy, tedious, diverse gatherings of information that much of the rest of the contested information about global warming requires.
It seemed (seems) to me that the original article claimed more for the mass balance equation than was justified, and that that was unwise. We can only establish that there are not “net sources [of CO2 to the atmosphere] … larger than anthropogenic emissions” by evidence from the environment. That evidence is there in the environment: messy, complex, diverse as is all environmental evidence. But it isn’t in the mass balance equation, and claiming that it is (ie that “proof for the human origin of the increase” ) doesn’t help the argument: I suspect it just makes the doubters more doubtful.
Dikran: “I don’t see the fact that [the natural environment may have] a component that is a net source makes a difference”.
It makes all the difference in the world: it means you cannot claim that the rise in atmospheric CO2 is entirely (or even predominantly) due to human actions. It lets those who wish to deny human responsibility off the hook. If there really was a volcano in the Pacific churning out 80Gts/year of CO2, there really wouldn’t be much point in concerning ourselves about human emissions of just 8Gts/year – but the mass balance equation cannot tell us if that is indeed the case – only the wider environment is able to tell us that it is not.
Paul Birch says:
August 11, 2010 at 12:23 pm
Both Bob and Jack have in fact increased the number of sweets in the jar. Both have caused an increase in the number of sweets in the jar. (Most of the extra sweets in the jar have in fact been put there by Jack). These facts are not affected by the additional fact that Jack has also been responsible for decreasing the number of sweets in the jar.
If you separate Jack’s inputs from Jack’s outputs as you (and Arthur) do, then indeed you are -again- confusing the origin of individual sweets with the origin of the increase in total number of sweets. The same confusion that many before you have had.
Jack indeed caused the relative increase of his own specific sweets (the origin of individual molecules CO2), but he didn’t cause the increase in total sweets (the origin of the increase in total CO2), because an increase or decrease in any reservoir is caused by the difference between inflows and outflows, not by an inflow or an outflow in separation.
Paul Birch wrote:
“Both Bob and Jack have in fact increased the number of sweets in the jar. Both have caused an increase in the number of sweets in the jar. (Most of the extra sweets in the jar have in fact been put there by Jack).”
Sorry that is just daft, Jack has put sweets in the jar but he has not *increased* the number of sweets in the jar because he has been taking more sweets out of the jar than he has put in. Unless of course you have an odd definition of the word “increase”.
If Bob wasn’t putting sweets in the jar, would jack still be increasing the number of sweets in the jar if he carried on doing exactly what he was doing before?
Arthur Rörsch says:
August 11, 2010 at 11:20 am
Dear Dikran,
I am not responding to your posts, because I am behind reading all the new posts.”
Well do read that one, it exposes the flaw in your reasoning, as Ferdinand points out.
“Besides one, the metaphor of the banking account. I do not like considering these kind of methaphors. They always have their limitations. I restrict myself to the real accounting of the CO2 balance. ”
As you are presenting a simplified mathematical model of the real CO2 balance, your own model similarly has its limitations, but that did not stop me from genuinely engaging in the discussion of the science.
“May be you forgot in your metaphor there may be sombody robbing your account, or that an anonymous maffia member deposited an amount for ‘favours’.”
(i) that is pure sophistry
(ii) I anticipated such sophistry in my post by specifically excluding meaningless ways in which the model could be made more complicated (and the issue obfuscated) but which have no relation to the real carbon cycle.
Slioch: If we both agree that the natural environment is a net sink, in what way is it a cause of the increase given that it is taking in more carbon from the atmosphere than it puts in?
Slioch says:
August 11, 2010 at 12:49 pm
There is no problem with claiming that the the natural environment as a whole is a net sink: that indubitably is what the mass balance equation establishes (given the human emissions of +8Gts/year, and net atmospheric gain of +4Gts per year, or thereabouts). I agree entirely with your first paragraph.
But what mass balance equation cannot establish from those two bits of information alone (plus conservation of mass) and does not allow us to claim is “proof for the human origin of the increase” as claimed in the original article. That requires a demonstration that there are not things like my mythical volcano in the Pacific, and the mass balance equation alone provide no information in that regard: that requires environmental information from outwith the mass balance equation.
Slioch, I fear that you are looking too much to the origin of the CO2, not the origin of the increase:
Even if there was an unknown volcano spewing 80 GtC in the atmosphere, but the rest of nature absorbs more than that + the rest of the natural inputs, then nature as a whole is a net sink for CO2, compared to human emissions which are a net source. Alternative separations where human emissions are mixed with parts of the natural flows are valid, but don’t answer the question “us against nature”, only a proper separation does answers that question.
In the case of Narkid, he would have been wrong in his conclusion that the volcano was the origin of the increase if he didn’t know of the human emissions and lumped everything together supposing everything was natural. If he had known of the human emissions, he would have separated that out and would have found that the extra volcanic input was not the cause of the increase.
In our case, we know of the human emissions and we know the increase, therefore we know that nature as a whole is a net sink and not the cause of the increase…
When are we going to get to the only meaningful question: will an increase in CO2 cause runaway global warming and climate catastrophe? Or, on balance, is an increase in CO2 beneficial for the biosphere?
Until then, these arguments sound like Big Brother in George Orwell’s 1984:
“Choco rations have been increased to 25 grams per week, up from 30 grams per week.” ☺
Smokey,
Thanks, I agree that it is time to end this discussion. It differs the attention from the real question. But as I have said several times to Arthur Rörsch: the insistence on a possible non-human origin of the increase of CO2 in the atmosphere, where the evidence is overwhelming, makes that the credibility of all skeptics is undermined, not only of those who still believe that alternative explanations exist.
Therefore this discussion is necessary, to weed out misconceptions in the skeptics world…