While this article makes a strong case, looking at SST and CO2 can also be revealing:
A review of this WUWT post might also be instructive: A look at human CO2 emissions -vs- ocean absorption
From Columbia University: Oceans’ Uptake of Manmade Carbon May be Slowing
First Year-by-Year Study, 1765-2008, Shows Proportion Declining
(Click on image to view larger version)
Carbon released by fossil fuel burning (black) continues to accumulate in the air (red), oceans (blue), and land (green). The oceans take up roughly a quarter of manmade CO2, but evidence suggests they are now taking up a smaller proportion.
Credit: Samar Khatiwala, Lamont-Doherty Earth Observatory.
The oceans play a key role in regulating climate, absorbing more than a quarter of the carbon dioxide that humans put into the air. Now, the first year-by-year accounting of this mechanism during the industrial era suggests the oceans are struggling to keep up with rising emissions—a finding with potentially wide implications for future climate. The study appears in this week’s issue of the journal Nature, and is expanded upon in a separate website.
The researchers estimate that the oceans last year took up a record 2.3 billion tons of CO₂ produced from burning of fossil fuels. But with overall emissions growing rapidly, the proportion of fossil-fuel emissions absorbed by the oceans since 2000 may have declined by as much as 10%.
Some climate models have already predicted such a slowdown in the oceans’ ability to soak up excess carbon from the atmosphere, but this is the first time scientists have actually measured it. Models attribute the change to depletion of ozone in the stratosphere and global warming-induced shifts in winds and ocean circulation. But the new study suggests the slowdown is due to natural chemical and physical limits on the oceans’ ability to absorb carbon—an idea that is now the subject of widespread research by other scientists.
“The more carbon dioxide you put in, the more acidic the ocean becomes, reducing its ability to hold CO₂” said the study’s lead author, Samar Khatiwala, an oceanographer at Columbia University’s Lamont-Doherty Earth Observatory. “Because of this chemical effect, over time, the ocean is expected to become a less efficient sink of manmade carbon. The surprise is that we may already be seeing evidence for this, perhaps compounded by the ocean’s slow circulation in the face of accelerating emissions.”
The study reconstructs the accumulation of industrial carbon in the oceans year by year, from 1765 to 2008. Khatiwala and his colleagues found that uptake rose sharply in the 1950s, as the oceans tried to keep pace with the growth of carbon dioxide emissions worldwide. Emissions continued to grow, and by 2000, reached such a pitch that the oceans have since absorbed a declining overall percentage, even though they absorb more each year in absolute tonnage. Today, the oceans hold about 150 billion tons of industrial carbon, the researchers estimate–a third more than in the mid-1990s.
For decades, scientists have tried to estimate the amount of manmade carbon absorbed by the ocean by teasing out the small amount of industrial carbon—less than 1 percent—from the enormous background levels of natural carbon. Because of the difficulties of this approach, only one attempt has been made to come up with a global estimate of how much industrial carbon the oceans held—for a single year, 1994.
Khatiwala and his colleagues came up with another method. Using some of the same data as their predecessors— seawater temperatures, salinity, manmade chlorofluorocarbons and other measures—they developed a mathematical technique to work backward from the measurements to infer the concentration of industrial carbon in surface waters, and its transport to deep water through ocean circulation. This allowed them to reconstruct the uptake and distribution of industrial carbon in the oceans over time.
Their estimate of industrial carbon in the oceans in 1994—114 billion tons—nearly matched the earlier 118 billion-ton estimate, made by Chris Sabine, a marine chemist at the National Oceanic and Atmospheric Organization in a 2004 paper in the journal Science.
Sabine, who was not involved in the new study, said he saw some limitations. For one, he said, the study assumes circulation has remained steady, along with the amount of organic matter in the oceans. “That being said, I still think this is the best estimate of the time variance of anthropogenic CO₂ in the ocean available,” said Sabine. “Our previous attempts to quantify anthropogenic CO₂ using ocean data have only been able to provide single snapshots in time.”
About 40 percent of the carbon entered the oceans through the frigid waters of the Southern Ocean, around Antarctica, because carbon dioxide dissolves more readily in cold, dense seawater than in warmer waters. From there, currents transport the carbon north. “We’ve suspected for some time that the Southern Ocean plays a critical role in soaking up fossil fuel CO₂,” said Khatiwala. “But our study is the first to quantify the importance of this region with actual data.
The researchers also estimated carbon uptake on land, by taking the known amount of fossil-fuel emissions and subtracting the oceans’ uptake and the carbon left in the air. They were surprised to learn that the land may now be absorbing more than it is giving off.
They say that until the 1940s, the landscape produced excess carbon dioxide, possibly due to logging and the clearing and burning of forests for farming. Deforestation and other land-use changes continue at a rapid pace today—but now, each year the land appears to be absorbing 1.1 billion tons more carbon than it is giving off.
One possible reason for the reversal, say the researchers, is that now, some of the extra atmospheric carbon—raw material for photosynthesis–may be feeding back into living plants and making them grow faster. “The extra carbon dioxide in the atmosphere may be providing a fertilizing effect,” said study coauthor Timothy Hall, a senior scientist at NASA’s Goddard Institute for Space Studies. Many other scientists are now working to determine the possible effects of increased carbon dioxide on plant growth, and incorporate these into models of past and future climates.
Khatiwala says there are still large uncertainties, but in any case, natural mechanisms cannot be depended upon to mitigate increasing human-produced emissions. “What our ocean study and other recent land studies suggest is that we cannot count on these sinks operating in the future as they have in the past, and keep on subsidizing our ever-growing appetite for fossil fuels,” he said.
In a related paper in Nature, Khatiwala describes how the research was done.
The article says:
We only have somewhat accurate seawater temperature measurements for the last half century or so. We have very little information about global salinity. Chlorofluorocarbons have only been made for half a century. Our understanding of the totality of ocean currents is low.
Could someone explain to me how they can use these to say how much carbon was absorbed by the ocean in say 1850 or 1920? Sounds like guesswork to me, not science.
Well the first pink graph seems quite hokey to me.
So it shows two different “line” plots.
But the big heading at the top alleges that the plot “shows the dependence of atmospheric carbon dioxide on global average sea surface temperature”
No it doesn’t ! there’s not a scintilla of information (on that graph) that would indicate that either one depends on the other. Now the casual observer might “infer” that the CO2 is dependent on the SST; but then another equally casual observer, might “infer” that in fact it shows that the SST is dependent on the CO2. How could yopu possibly distinguish those two cases, based on those graphs. Simply switching the X and Y axes would presumably switch the dependence. You could probably plot a rolling average of the population of the USA over the same time period, and plot it against either the CO2 or the SST, and infer that the US population is dependent on the sea surface temperature; or on the atmospheric CO2 whichever point you wanted to promote.
As for the second graph; I don’t take kindly to graphs that have the positive Y-axis going down instead of up; for whatever reason; theres’ no simple way by eye to deduce that what the authors claim is true, that the ocean take up of CO2 is slowing down.
Now the rogue observer might infer that there is some other unknown (to the grapher) driving force, that is controlling both the SST and the CO2.
Well the mathematicians might infer that those two plotted quantities; CO2 and SST; and rolling averages at that, show a strong correlation. But it is quite trivial to construct data sets that show strong correlation; yet have no cause and effect relationship whatsoever.
But as I said above; absolutely nothing on that page indicates that either of those quantities is dependent on the other
Gosh what a lot of mays and might bes, and what delightfully circular way of going about it.
For a rather different opinion try this excellent article at CO2 Science.
http://www.co2science.org/articles/V12/N31/EDIT.php
It has further links worth exploring.
Kindest Regards
Here’s an excellent site on the topic:
http://www.seafriends.org.nz/issues/global/acid2.htm
He also mentions the 83 year unsubstantiated “correction” made by the IPCC on the Siple data to get it to align with Mauna Loa CO2. Has there been any subsequent work on validating ice core CO2 data ?
supercritical (10:25:29) :
4. What will happen if the vessel is 4 km deep?
for Supercritical,
You don’t give enough information to give more than vague answers to you quiz, but here goes.
1. Depends on what type of gage you have as well as the temperature and volume of your tank.
If the gage reads in PSIG, then the gage reading won’t change.
If the gage reads in PSIA, then the reading will go down, how much depends on the temperature and volume of the tank. The bigger and colder the tank, the more the reading will go down.
And it will stabilize within minutes, but will take longer if there is a bigger or colder tank.
2. Open the tank to atmosphere and the tank will suck air in.
3. The amount of CO2 that will dissolve in the tank in this case depends on the volume and temperature of the tank. It will take more if the tank is cold and big.
In regards to some of the acid base questions here are some explanations.
Neutrality occurs when the amount of H+ ion and OH- ions are equal in solution. The pH that this occurs at is very slightly above 7, as the product of the concentrations of H+ and OH- is very slightly above 1.0 EE -14 and increase slightly with temperature.
Even if the oceans are basic, with pH above 7.0, it is correct to say they are becoming more acidic if the pH is dropping even though the pH remains above 7.0.
The reason is that things can be both acidic and basic at the same time, and it is incorrect to say something is acidic and not basic, unless you are talking about protons, which are always acidic, or helium atoms, which are always basic. Everything else is both.
An example is sodium bicarbonate, which is applicable to the discussion, which is NaHCO3. It neutralizes both acid and base. Take a solution of sodium bicarbonate and add acid, and you get the salt of the acid and H2CO3, or add base, for example NaOH, you get Sodium carbonate and water.
And H2CO3 is also what you get when you dissolve CO2 in water.
Change the NaOH to CaOH and you get calcium carbonate or limestone.
And water is both an acid and a base.
Sorry for the chemistry lesson.
Here’s a carbon sink for you, http://spacefellowship.com/2009/09/11/plentiful-plankton-from-space/
Raw numbers on something that size? Better than the estimates for this one? http://www.earthweek.com/2009/ew091016/ew091016c.html
And catch the snow on the ground in the first shot, not exactly prime living conditions, but hey as long as the plankton like it!
Putting more food into the bottom of the food chain leads to a larger food chain, hard to see how that could be a bad thing.
Mr Ace
– If you want it to be 4km deep, it can be … AFAIK it should make no difference
and bob,
yes, assume a PSIA guage. And assume a constant room-temperature throughout, as implied, to keep things simple.
Again AFAIK volume should make no difference … but if you need it, assume 50 or even 100 litres of water.
It’s not that the upper ocean is saturated with CO2 that is the issue, it’s that only the upper ocean is in direct contact with the atmosphere. It’s over the ocean-atmosphere boundary that diffusional CO2 exchange occurs and hence the boundary layers (both atmospheric and oceanic) where CO2 exchange is occuring is where Henry’s Law directly applies.
Not quite. The roughly 50:1 partitioning of inorganic C (as CO2 in the atmosphere and DIC in the ocean) is simply the ratio you get for the prevailing chemical conditions. The partitioning of CO2 between the air and seawater fractions is not constant though–it varies non-linearly as you change DIC concentration and/or total alkalinity (i.e., acid neutralizing capacity). See Stumm and Morgan (Aquatic Chemistry), Zeebe and Wolf-Gladrow (CO2 in Seawater), etc. for extensive discussions of carbonate chemistry.
The change in buffer intensity for a given change in DIC is often expressed with the short-had Revelle factor (good for back of the notebook estimations). For more precise answers you’ve gotta do the calculations.
As above, it doesn’t, but Henry’s Law only directly operates at the ocean-atmosphere interface, where CO2 exchange actually occurs.
Yes, definitely. A soda or bottle of soda in contact with pure CO2 is something like the boundary layer in the ocean and atmosphere. CO2 exchange is relatively fast there. However, it takes thousands of years for an equivalent parcel of water to be transported though the ocean via thermohaline circulation.
Yep, there is a fair bit of data. I’d suggest Millero, 2006 Chemical Oceanography as a starting point.
Luboš Motl (07:57:57) :
“Of course I agree that in the extremely long run, the actual rise in the atmosphere will be negligible because the oceans return us to the equilibrium value that will only be raised by 1/50 of our future emissions from the present values. At the very end, 49/50 of the added CO2 will drop to the ocean while 1/50 will stay in the atmosphere.”
The problem with this chain of logic is that it likely contradicts the widely disseminated claim that anthropogenic emissions are a small fraction of natural emissions.
Here is a simple model strictly to illustrate the point.Suppose the amount of CO2 in the atmosphere is C, and its nominal equilibrium value is Co. Consider a differential equation of the form
Cdot = (Co – C)/tau + a
where “a” is the anthropogenic forcing and tau is the time constant. Suppose tau is very large, so that (Co – C)/tau is negligible, and the equation is approximately
Cdot := a
In the near term, the value of C is approximately
C = Co + integral(a)
Aha! So, we go up approximately by integral(a). Since integral(a) is about double the overall rise we have seen thus far, then it is perfectly plausible that most of the rise we have seen so far is due to “a”, right?
But, wait. Co/tau actually represents the rate of CO2 coming back into the system to keep it steady at C = Co without the anthropogenic forcing. It is said that “a” is no greater than 3% of natural emissions at the present time (and you say 1/50 or 2%), so we must have at most a is less than or equal to 0.03*Co/tau to date. If tau is very large, then “a” will be negligible. Since we know “a” is not negligible, tau cannot be very large.
In fact, if you assume Co is about 300 ppm more or less, and “a” is maybe 1-5 ppm/year at its maximum, then tau is less than or equal to 0.03*300/1 = 9 years. In this model, C is never greater than 1.03*Co up to the present time, being limited to Co*(1.03-0.03*exp(-t/tau)) up to the present time.
The model may be extremely simplified, and nonlinearties change the gains based on concentration, temperature, and other things. But, you can still analyze things the same way via linearization, and the result you come up with is that the local sensitivity has to be much greater than I believe would be likely given the historical record.
Chris,
Thanks for your post. I am trying to keep things simple, so given the rough 1:50 ratio of atmospheric CO2 to dissolved CO2, that Henry’s law predicts at any level of partial pressure of CO2, I do understand that this ratio varies a bit for different conditions of salinity, etc .. (as well as temperature which I haven’t go to yet )
But, surely it does not vary all the way down to 1:2 as Lubos Motls’ post implies?
And \as I note that you do agree that the soda-bottle analogy does support Henry’s law; perhaps you could have a go at my experiment-quiz, which you can find upthread a little.
Supercritical,
By my calculations, the volume does make a difference.
For room temperature with a 1 liter tank the final gage pressure is 0.53 bar.
For room temperature with an 100 liter tank the final pressure is 0.01 bar.
Does that agree with you?
Re: Phillip Bratby (23:18:04)
What do suggest we re-name it, NOAA ?
Bart (15:02:01) :
What is Co here? We don’t know what that is. You need to model the ocean, too. And then the trees and dirt, for good measure. I think what you’re also losing is that the natural flows from ocean to atmosphere and from atmosphere to ocean take place at different places on the earth. You need a global model to capture that.
The net transport from atmosphere to ocean (at any given spot) will have the driving force (actual partial pressure of CO2 in the bulk atmosphere) minus (the partial pressure of CO2 that the air right at the surface would have, if it were in equilibrium with the CO2 in the top layer of the water, as expressed by Henry’s Law).
But then, you have to consider all the inorganic chemistry (as the CO2 goes to bicarbonate), and the interactions with biology, and the actual patterns and time scale of mixing with the deap ocean, and the temperatures and circulation in the ocean, and the rate of carbon sedimenting out to the bottom of the ocean, and you’d have to get net transport into the ocean at the Southern Ocean, net transport out of the ocean in the tropics…
You’ll note there are multiple time scales here, as there are multiple processes with different time scales – diffusion at the surface, mixing with the deep ocean, response of marine biology, etc.
Pretty soon, you’d have re-invented the wheel that’s already been built and published by David Archer.
Sometimes a simple cartoon model can be instructive. I suppose this one could be, but only over a very small section of area, and only in the well-mixed top part of an ocean.
It absolutely won’t give you the global outflows and inflows into the ocean; you need a global model for that.
Vincent (04:35:09) :
“Wasn’t there a recent paper from Bristol universtity that came to the opposite conclusion, that the absorbtion of CO2 has been increasing steadily? ”
I was wondering if anybody would notice these two papers were on similar topics. That paper (Knorr, 2009) was much, much more simple than this one. Knorr basically divided the red curve (air) by the black curve (emissions)* in the figure above, and found that there was no significant trend in the resulting fraction (airborne fraction). Though by his method, if there was a subtle change in the airborne fraction in the last decade, I don’t think he’d have found it. If these guys (Khatiwala et al) discuss the airborne fraction, I didn’t see it on skimming the paper. So it isn’t obvious there is an opposite conclusion.
[*Also, I think Knorr’s version of the black curve included some things that are in these guys’ green curve (land); something to check. Note that the curves look smoothed in this new paper.].
Knorr did not even attempt to find the blue curve (ocean) above, as it requires a good deal more work. So the major contribution of this paper is that they found that blue curve, assuming they did a good job of it. The green curve is then simply found by subtraction, they they claim it roughly matches what others have found going forwards.
The attention comes from the ocean sink (blue curve) not quite keeping up the pace recently. On the other hand, the land and biosphere (green curve) picks up some of the slack.
Given how complicated this one is, I’d remember this work, but wait to see what else gets published in this area.
Something about the c02 cycle puzzles me. There seems to be considerable agreement that about half the anthro CO2 introduced into the atmosphere is removed within a year, or less. Some is dissolved in sea water, some taken up by terrestrial and marine plants, and some (about 25%) disappears into the “missing sink.” This loss fraction appears to remain constant regardless of the atmospheric partial pressure of CO2 (at least that has been the assumption until this new paper).
At the same time, the “accepted” half-life of a given quantity of CO2 added to the natural cycle is 38 years. E.g., if we were to instantly add 100 ppmv of CO2 to the atmosphere, then (ignoring all possible feedbacks) that addition would be reduced to 50 ppmv in 38 years, halved again in another 38 years, etc., until a new equilibrium was reached.
These two assumptions are clearly inconsistent. If we add 4 ppmv/annually, but only 2 ppmv is measured only months later, how can the half-life be 38 years?
Anyone have an explanation for this?
bob,
Do your results point to Henry’s law needing to include a term for the ratio of gas and liquid volumes?
carrot eater (17:06:44) :
“But then, you have to consider all the inorganic chemistry (as the CO2 goes to bicarbonate), and the interactions with biology, and…”
No, that’s really not it, CE. As long as the model is globally linear and time invariant*, in the steady state, I am never going to get more percentage-wise than the extra forcing I put in. I might get a transient with some overshoot, but in the end, it’s going to settle down proportional to the input**. Moreover, the magnitude of any transient is going to depend on the rapidity of the increase in the input forcing***, and our increasing CO2 output has been at a gradually rising, measured pace over the past century.
Suppose there were a large transient, though, and it took 50 years from now to settle out****. Further suppose that, by that time, we were outputting 10% of the level of the natural flux into the atmosphere. The CO2 level, according to such a model, would only be up 10% from this forcing. Given that anthropogenic forcing currently stands accused of increasing CO2 concentration 30% or more in the last 50 years, that’s not a very big deal.
What is needed to square the circle is for some nonlinearity to produce a markedly increasing (factor of 10 or more) marginal sensitivity. But, if such a large sensitivity were to exist, it should show up as increasingly chaotic behavior due to yearly variations in the natural forcing (the natural variations would be amplified, too). I have no access to the raw data so, for all I know, they could be seeing that, but I tend to think they would have broadcast it by now, because it would significantly bolster their case.
* constant gain parameters – time varying system parameters usually come about because of linearization of some nonlinearity along a particular trajectory though, so this is almost redundant
** please don’t argue with me on this, it is definitional for linear systems – look for more promising angles of attack in what comes later
*** how far the frequency content is beyond the bandwidth of the closed loop system or, relatedly, to what order the input is continuous
****I am doing a reductio here, because that likelihood, in my opinion, is slim to none
Bart, let me maybe make it more clear.
You have a term (Co – C)/tau. You don’t know what Co is, which is itself troubling, but let’s go with it. If the concentration in the air exceeds Co, then this term will get rid of it by removing it to some unspecified sink, by unspecified physical processes. Very well.
But Co-C is just your driving force. If you really want to equate the term with some physically observed value, then it has to be the global NET carbon flow into the atmosphere. For the moment, let’s use the numbers in here, as they’re handy:
http://en.wikipedia.org/wiki/File:Carbon_cycle-cute_diagram.svg
At the time of the diagram, your term (Co-C)/tau is equivalent to -2.2 GtonCarbon/year (I’m not going to bother fussing with the conversion to ppm).
Meanwhile, at the given time, your term ‘a’ is equivalent to +5.5 GtonCarbon/year (again, not bothering with converting to ppm)
Assuming I added correctly, about 60% is staying in the air.
So far, so rough, but OK for limited purposes. We should stop there, as it’s as far as this line of inquiry is going to take us.
Here’s your problem: you try to go further, and try to assign physical values to things which you cannot. “Co/tau actually represents the rate of CO2 coming back into the system to keep it steady at C = Co without the anthropogenic forcing.”
No, it doesn’t represent that, at all. You seem really wanting to separate (Co-C)/tau into two separate elements, Co/tau and C/tau, and setting them equal to things you see on the diagram: the sum of the inflows, and the sum of the outflows. You simply can’t. Co-C is just your global driving force; written as you have, you can’t break it up and give the two parts some physical meaning. Over the globe, the term adds up to -2.2 gton carbon/year at the time of the diagram. You really want to equate Co/tau with 211.6 gton/year and C/tau with 213.8 gton/year, but that isn’t valid. In order to actually find the INDIVIDUAL flows in and out of the atmosphere, you absolutely need a global model that describes all those individual flows, as in my last comment – a global model that has oceans, ocean chemistry, ocean biology, ocean circulation, and the works. All your model can do is give some really rough idea of the overall NET flow, based on the assumption that the net flow will have a single time scale and a simple driving force, as expressed by (Co-C)/tau.
In retrospect, my last comment might have been unduly picky. The main disconnect is that I don’t understand exactly what Bart is trying to learn from his little model. What, exactly, are you trying to show? Once that is clear, then the level of detail required in the model would also be more clear.
If emissions stopped tomorrow, and went straight to zero, then a thinking along Bart’s lines would be vaguely useful. For the first couple years, the net outflow from the atmosphere would probably be about what it is now (as Motl says above, I think); over time this net outflow would necessarily decrease as some steady state is approached (as Bart’s model captures). You might get some rough ballpark idea of a half-life from here.
However, it must be remembered that there isn’t a single physical process here; there are multiple, each with different time scales. And the steady state value Co isn’t obvious ahead of time. So a simple little exercise like this might add some rough understanding, but to get the whole picture, I’d suggest looking at the work already done by David Archer.
Has anybody out there looked at Henry’s Law lately? That “experience curve” looks a LOT like a plot of experimental data for a chemistry lab on Henry’s Law.
Tadchem,
Yes, I have, and you are right, it does look a lot like Henry’s law.
But which is it?
The warming oceans increasing the CO2 in the atmosphere or the increasing CO2 warming the oceans?
Hmmmmmmmmmmmmmm,
Supercrit,
No, I didn’t consider any ratio of volumes between the gas and the liquid.
I calculated the amount of CO2 gas present in 1 liter of CO2 at room temperature using the Ideal Gas Law, in moles.
Then I calculated the partial pressures by Henry’s law for the liquid and (partial) pressure by the Ideal Gas Law for the gas part, using the amount in moles calculed above minus n for one and n for the other, (summed they equal the amount calculated above) and set them both equal and sovled for the amount of CO2 in moles in each part (gas and liquid)
Then used that amount to calculate the pressure.
All that showed to me is that CO2 dissolves in water.
carrot eater (07:01:51) :
None of this matters, really. What I said is true no matter what your model is. If it is globally linear, then the sensitivity to forcing is linear.
“The main disconnect is that I don’t understand exactly what Bart is trying to learn from his little model. What, exactly, are you trying to show?”
What I am showing is that things are not so simple as “we have put in X gT of carbon and atmospheric CO2 has risen by 1/2 that amount, therefore the rise is due to us”. That statement is naive to the point of imbecility, and I have ground the enamel off my teeth from hearing it so often.
The other thing I am showing is that, in order to accept the AGW hypothesis, you have to accept an nonlinear climate response with dramatically increasing sensitivity, for which there appears to be little evidence, at least in what has filtered down to my level. In situations like that, my experience has been that a narrative has been constructed, and the caution and uncertainties expressed behind closed doors have not made it out to the final report for public consumption. On a topic as critical as this one for the health and well-being of the citizens of this nation, I am not content merely to take the word of “experts”. I want proof.
I looked up your David Archer on the web. He does not appear to have published anything openly available which delves into the nuts and bolts of the actual climate models. Do you have a link to such a reference?
Bart (09:19:11) :
“What I am showing is that things are not so simple as “we have put in X gT of carbon and atmospheric CO2 has risen by 1/2 that amount, therefore the rise is due to us”.”
Taken on its own, you couldn’t say that without a doubt, but it’d be very strongly suggested. That’s why people bother to study the carbon cycle. The ocean and land/biosphere are net sinks for carbon. The ocean pH is decreasing, after all. (The land is a sink if you put deforestation effects into the human emission column). That leaves no option; the only net source is human activity. On top of that, carbon isotope data is consistent with all of this. Your little model isn’t going to change any of that – especially since it uses some of the data from all that, anyway. To change the picture, you’d have to challenge the flows on the carbon cycle itself, and somehow turn the ocean into a net source.
“The other thing I am showing is that, in order to accept the AGW hypothesis, you have to accept an nonlinear climate response with dramatically increasing sensitivity”
Increasing sensitivity of what to what? So far, we’ve been discussing the carbon cycle. Are you still on the carbon cycle itself? Are you surprised that the oceans are a net sink?
“I looked up your David Archer on the web.”
The paper I had in mind was “Fate of fossil fuel CO2 in geologic time”, Journal of Geophysical Research, vol 110 (2005). I don’t know if it’s floating around in the public domain. But no matter. The Global Carbon Project or somebody else must have stuff available to look at.
bob
From my thought-quiz, with a sealed container with N litres of water and a 1 litre headspace initially filled with CO2 at 1 bar. My first approximation at a result would be a for an absolute pressure reading stabilising at a steady 0.02 bar, within seconds.
Then if I increased the CO2 into the headspace so that I got a steady 2 bar reading, I reckon I’d need to inject 100 litres of C02. Again, this should be pretty quick.
So if I started the quiz again to simulate the atmosphere, and filled the 1litre headspace with CO2 to get a steady reading of 300 ppmv ( or 0.3 millibars, or 0.3 cc) I’d reckon on injecting about 15 cc of CO2.
And then, if I wanted to simulate the increase of atmospheric CO2 by 2 ppm/year, ( i.e. ~ 0.003 millibars, or 0.003cc) I would have to inject another initial 0.15 cc of CO2.
So what? It means that, to increase the 300 ppm of CO2 in the atmosphere by 2ppm, I would need to initially add 50x this amount, or 100 ppm. And then it would not take very long at all for the new reading to stabilise at the new 302 ppmv.
But there are estimates that claim that man puts out about 4 ppm/y of CO2 directly into the atmosphere ..so if after a short while 49/50 of it will be absorbed then we can only be accountable for around 0.04 ppm/y of the residual CO2 in the atmosphere. Where is that other 2 – 0.04 = 1.96/y ppm coming from?
My first idea is that we are looking for a CO2 source which is entirely coincidentally emitting some 50x more than man.
And, I would start by looking at CO2 from those recently discovered huge numbers of ocean hydrothermal vents (a form of volcano, after all ) and maybe separately, their warming effect down in the deep oceans, which could cause considerable outgassing from the local waters as well.
But next, I need a quick rule-of-thumb for the temperature effects on the Henry’s law ratio of 1:50 for CO2 and water, in the form of a modifier for the ratio, per degree C. Does anybody have such a number to hand?