Correlation of Net CO2 emissions with climate properties shows that the growth in CO2 may be natural
Story submitted by WUWT reader Steve Brown
The narrative of the catastrophic anthropogenic global warming has been challenged at many levels but this presentation by Professor Murry Salby, Chair of Climate at Macquarie University rips up the very foundations of the story.
The talk (in the video below) was given at the Sydney Institute 2nd Aug 2011
He elegantly shows that there is a solid correlation between natural climate factors (global temperature and soil moisture content) and the net gain (or loss) in global atmospheric content when the latter is averaged over a two year period. The hanging question remains, if natural factors drive more than 90% of the growth in CO2 how significant is the contribution of human generated emissions. The answer is simple… not very.
The talk has been covered in the past on Judith Curry’s blog, and an abstract of the talk is here . But this is the first time I have encountered a video of the talk or been able to see the slides which he referenced.
Fascinating.
Bart, nobody is saying that that the sinks are constant. The mass balance argument makes no assumption whatsoever about the mechansisms governng the natural sources or sinks. If you look at the data, as you were asked to do on the previous thread, you will find that the inferred difference between natural emissions and natural uptake is highly variable.
I pointed out your error!!!
En(t) – Un(t) is not entirely natural!!!
Un(t) has a part which is responding to the natural forcing, and a part which is responding to the anthropogenic forcing!
If Ea(t) were zero, then and only then would En(t) – Un(t) be entirely natural.
Bart wrote: “If Ea(t) = Una(t), then the increase is entirely natural!”
The flaw in this argument is easily demonstrated via analogy (indeed as I did on the previous thread):
Assume I share a savings jar with my wife (guarded by a team of loyal ninja to make sure only my wife and I have access to the jar). Assume I put in 4 euro a month (corresponding to Ea) and my wife puts in 90 euro a month (corresponding to En) but also takes out 92 euro a month (corresponding to Un). Our savings would be rising at 2 euros a month, and most rational people would say that I was 100% responsible for the rise as my wife was taking more money out of our savings than she was putting in. It doesn’t matter if her deposits or withdrawals are a response to my depsits, as long as she spends more than she saves, she is opposing the rise in our savings.
The same is true of the carbon cycle, we know that natural uptake is greater than natural emissions, so we know that the natural environment is opposing the rise in atmospheric CO2.
Here is a plot of the data, produced by Ferdinand Engelbeen:
Note that the difference between natural emissions and natural uptake, inferred from the observations of anthropogenic emissions and atmospheric CO2 using the mass balance argument, are constantly changing. Note however that they are always negative (as the natural environment has been a net carbon sink) and that there is a downward trend, which is the response of natural sources and sinks to increasing atmospheric concentrations. The mass balance doesn’t tell you anything about the mechanism involved, it just telss you what Un(t)-En(t) is if you happen to know what dC(t) – Ea(t) is (which we do). It really isn’t rocket science.
There is no flaw on my part. You are again using a flawed analogy of a static system.
Bart wrote: “En(t) – Un(t) is not entirely natural!!!
En(t) and Un(t) were defined as being total natural emissions (from all natural sources) and total natural uptake (into all natural sinks) then En(t) – Un(t) is the net response of the natural environment. If you think this is not entirly natural it just means that you don’t understand the argument.
Un(t)-En(t) is not entirely natural. Un(t) has a part which is induced by anthropogenic forcing Ea(t).
Just because the “uptake” is natural does not mean it is taking up only natural emissions. Un(t) has a part which is induced by anthropogenic forcing Ea(t).
Bart wrote “There is no flaw on my part. You are again using a flawed analogy of a static system.”
The same is true whether the system is static or dynamic. If my wife is taking more out of our savings than she is putting in then she is opposing the rise in our savings. This is true whether her deposits and withdrawals are constant or variable, this is true whether her deposits and withdrawals are a response to my deposits or not.
Likewise if the natural environment is taking more CO2 out of the atmosphere than it is putting in then it is opposing the rise rather than causing it. This is true whether the sources and sinks are constant or variable; it is true whether or not the sources and sinks act in response to our emissions (actually they respond to changes in atmospheric CO2, rather than directly to our emissions).
Now it is obvious that you can’t find a flaw in my argument (if you could you would specify the step involved (i)-(vi) and identify the error) so all you can do instead is point out a flaw in an argument I am not making. That is what is known as a straw man, and it fools nobody.
There is a part of Un(t), which I called Unn(t), which takes up natural emissions. There is another part, which I called Una(t), which takes up anthropogenic emissions. Un(t) responds dynamically to both En(t) and Ea(t).
Bart wrote “Un(t)-En(t) is not entirely natural. Un(t) has a part which is induced by anthropogenic forcing Ea(t).”
Irrelevant, as I have pointed out if my wife is taking more out of our savings that she puts in then she is opposing the rise in our savings, and this is true whether or not her deposits and withdrawals are a response to my deposits or not. Whether the natural environment is causing the rise or opposing it depends only on the difference between natural emissions and natural uptake. The reason for that difference is irrelevant.
Sorry to be obtuse, but the argument that CO2 absorption into the oceans is a different process than CO2 outgassing from the oceans cannot account for the acidifiction problem. If atmospheric CO2 is being sucked out by plankton in the oceans, which die and take the carbon to the bottom of the oceans, that would not cause ocean acidification. CO2 locked in plankton or other sea life does not change the chemical properties of the ocean water – at least not until the life decays and the molecules are taken up into the water.
The explanation I was looking for seems to be this: Cold, CO2-rich water from the ocean bottom circulates to the surface, and outgasses CO2 as it warms. But when the atmosphere has a higher partial pressure of CO2 due to man-made emissions, LESS CO2 from the CO2-rich cold water outgasses as it warms than it otherwise would. Thus the warmer water that is retained near the surface will retain more CO2 and thus be more acidic. On this explanation, the ocean surface water does not take in atmospheric CO2 on a net basis, causing acidification; it is simply that less outgassing happens, so the formerly colder water retains more CO2 in solution – increasing the acidity near the surface.
Does that make sense to anyone else?
dikranmarsupial says:
April 20, 2012 at 2:30 pm
“Whether the natural environment is causing the rise or opposing it depends only on the difference between natural emissions and natural uptake.”
No, it depends on the natural uptake of natural emissions ONLY. Apparently, the use of the word “natural” is confusing you. There are two types of natural uptake: natural uptake of natural emissions, and natural uptake of anthropogenic emissions. The natural sinks do not discriminate between the two.
If you still do not get it, then you are hopeless, and there is no way I can breach the impregnable wall of denial you have built up around yourself.
Bart, do you agree that once a molecule of CO2 is in the atmosphere, that there is no difference from one CO2 molecule to any other? (other than of course the fact that some are 12CO2 and others are 13CO2)
Bart wrote: “There is a part of Un(t), which I called Unn(t), which takes up natural emissions. There is another part, which I called Una(t), which takes up anthropogenic emissions. Un(t) responds dynamically to both En(t) and Ea(t).”
You are still ignoring the point. Whether the natural environment is causing or opposing the rise in atmospheric CO2 depends on whether it is putting more CO2 into the atmosphere than it is taking out or vice versa, it is as simple as that. You can slice and dice Un(t) however you like, but that doesn’t change the fact that the environment is a net carbon sink and has been for the last fifty years at the very least. Hence it has been opposing the rise in CO2.
“Whether the natural environment is causing the rise or opposing it depends only on the difference between natural emissions and natural uptake of natural emissions ONLY.”
The natural uptake of anthropogenic emissions would not occur without the input of the anthropogenic emissions in the first place. Therefore, that portion is not natural. It is not a given. You are implicitly assuming that the sinks are static, that they only take up natural emissions.
This is your error. This is your flaw. I have stated it explicitly. You are accounting Un(t) as being completely in the “natural” column. But, it ceases to be assignable there when it is taking up unnatural emissions.
Bart says
“So, we only know N-UA-UN. Suppose UA = A. Then M = N – UN, N is greater than UN, and the rise is entirely natural.”
This is not true. CO2 in the atmosphere is fungible. You can’t assign the excess CO2 entirely to nature or to man, you can say that both contributed to the increase.
Earlier you said that just because the observed rise in CO2 correlates with the predicted change which would occur based on the amount of carbon based fuels (assuming about 50% sequestration) that it doesn’t imply causality. You’re right correlation isn’t causality. But if you know that something should cause something else, and you see a correlation, then you are probably right. We know that burning things should increase the atmospheric content of CO2. We observe that the change is less than we would expect, so we deduce that some percentage is sequestered into the environment. Likewise we also observe that on a year to year basis natural fluctuations can affect CO2 concentrations, these seem to net to about zero however.
Peter says:
April 20, 2012 at 3:38 pm
“…do you agree that once a molecule of CO2 is in the atmosphere, that there is no difference from one CO2 molecule to any other?”
You should be asking the other guy that question. The very fact of it underlies my argument. The sinks respond the same to both anthro and natural concentration. They expand to consume all. Only by ignoring the natural uptake of anthropogenic input can you arrive at such a silly argument as this “mass balance”, which isn’t really a mass balance at all.
If you are going to balance them, you have to break it up the way I showed:
dC(t) = (Ea(t) – Una(t)) + (En(t) – Unn(t))
Ea(t) – Una(t) is the net anthropogenic input, and En(t) – Unn(t) is the net natural input. And, we have no idea what the proportions are of one to the other.
Bart wrote: “No, it depends on the natural uptake of natural emissions ONLY.”
No, again the savings jar analogy reveals this to be specious. I my wife is taking more out of the savings jar than she is putting in then she is opposing the rise in our savings. It doesn’t matter one iota whether she takes out coins I put in or coins that she puts in.
“There are two types of natural uptake: natural uptake of natural emissions, and natural uptake of anthropogenic emissions. The natural sinks do not discriminate between the two.”
No, again that is specious. Once a molecule of CO2 is in the atmosphere it makes no difference whether it is from an anothropogenic source or a natural one, it is just a molecule of CO2, just as a coin in the jar is a coin in the jar. A euro is a euro whether I put it in the jar or my wie did.
Colin says:
April 20, 2012 at 3:48 pm
“… you can say that both contributed to the increase.”
And, that is ALL you can say. You cannot say how much of one or the other did without knowing the nature of the sink dynamics.
I’ve got things to do. No doubt, more stupid words will be written against what I am explaining. It is really depressing.
dikranmarsupial says:
April 20, 2012 at 3:46 pm
“You can slice and dice Un(t) however you like, but that doesn’t change the fact that the environment is a net carbon sink and has been for the last fifty years at the very least. Hence it has been opposing the rise in CO2.”
Of course it has been opposing the rise. That is definitional. Sinks always oppose the rise of whatever item they are sinking. Hence the word “sink”.
It tells us nothing about the source of the rise.
I am going to repeat this just once and depart for now:
If you are going to balance them, you have to break it up the way I showed:
dC(t) = (Ea(t) – Una(t)) + (En(t) – Unn(t))
Ea(t) – Una(t) is the net anthropogenic input, and En(t) – Unn(t) is the net natural input. And, we have no idea what the proportions are of one to the other.
university level chemical kinetics course.
Phil. says:
April 20, 2012 at 12:17 pm
mwhite says:
April 20, 2012 at 11:41 am
So what about the CO2 ejected from volcanos???
It contains no C14, it’s a very small fraction of the natural sources however.
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From the link I gave earlier: http://carbon-budget.geologist-1011.net/
“Both tectonic and volcanic CO2 are magmatic and depleted in both 13C & 14C. In the absence of statistically significant isotope determinations for each volcanic province contributing to the atmosphere, this makes CO2 contributions of volcanic origin isotopically indistinguishable from those of fossil fuel consumption. It is therefore unsurprising to find that Segalstad (1998) points out that 96% of atmospheric CO2 is isotopically indistinguishable from volcanic degassing. So much for the Royal Society’s unexplained “chemical analysis”. If you believe that we know enough about volcanic gas compositions to distinguish them chemically from fossil fuel combustion, you have indeed been mislead. As we shall see, the number of active volcanoes is unknown, never mind a tally of gas signatures belonging to every active volcano. We have barely scratched the surface and as such, there is no magic fingerprint that can distinguish between anthropogenic and volcanogenic sources of CO2.”
Do read what he has to say about Keeling and the misuse of the Suess Affect.
Bart,
I don’t think they’re capable of understanding what you’re trying to explain.