An important new paper published today in Global and Planetary Change finds that changes in CO2 follow rather than lead global air surface temperature and that “CO2 released from use of fossil fuels have little influence on the observed changes in the amount of atmospheric CO2” The paper finds the “overall global temperature change sequence of events appears to be from 1) the ocean surface to 2) the land surface to 3) the lower troposphere,” in other words, the opposite of claims by global warming alarmists that CO2 in the atmosphere drives land and ocean temperatures. Instead, just as in the ice cores, CO2 levels are found to be a lagging effect ocean warming, not significantly related to man-made emissions, and not the driver of warming. Prior research has shown infrared radiation from greenhouse gases is incapable of warming the oceans, only shortwave radiation from the Sun is capable of penetrating and heating the oceans and thereby driving global surface temperatures.
The highlights of the paper are:
► The overall global temperature change sequence of events appears to be from 1) the ocean surface to 2) the land surface to 3) the lower troposphere.
► Changes in global atmospheric CO2 are lagging about 11–12 months behind changes in global sea surface temperature.
► Changes in global atmospheric CO2 are lagging 9.5-10 months behind changes in global air surface temperature.
► Changes in global atmospheric CO2 are lagging about 9 months behind changes in global lower troposphere temperature.
► Changes in ocean temperatures appear to explain a substantial part of the observed changes in atmospheric CO2 since January 1980.
► CO2 released from use of fossil fuels have little influence on the observed changes in the amount of atmospheric CO2, and changes in atmospheric CO2 are not tracking changes in human emissions.
The paper:
The phase relation between atmospheric carbon dioxide and global temperature
- a Department of Geosciences, University of Oslo, P.O. Box 1047 Blindern, N-0316 Oslo, Norway
- b Department of Geology, University Centre in Svalbard (UNIS), P.O. Box 156, N-9171 Longyearbyen, Svalbard, Norway
- c Telenor Norway, Finance, N-1331 Fornebu, Norway
- d Department of Physics and Technology, University of Tromsø, N-9037 Tromsø, Norway
Abstract
Using data series on atmospheric carbon dioxide and global temperatures we investigate the phase relation (leads/lags) between these for the period January 1980 to December 2011. Ice cores show atmospheric CO2 variations to lag behind atmospheric temperature changes on a century to millennium scale, but modern temperature is expected to lag changes in atmospheric CO2, as the atmospheric temperature increase since about 1975 generally is assumed to be caused by the modern increase in CO2. In our analysis we use eight well-known datasets; 1) globally averaged well-mixed marine boundary layer CO2 data, 2) HadCRUT3 surface air temperature data, 3) GISS surface air temperature data, 4) NCDC surface air temperature data, 5) HadSST2 sea surface data, 6) UAH lower troposphere temperature data series, 7) CDIAC data on release of anthropogene CO2, and 8) GWP data on volcanic eruptions. Annual cycles are present in all datasets except 7) and 8), and to remove the influence of these we analyze 12-month averaged data. We find a high degree of co-variation between all data series except 7) and 8), but with changes in CO2 always lagging changes in temperature. The maximum positive correlation between CO2 and temperature is found for CO2 lagging 11–12 months in relation to global sea surface temperature, 9.5-10 months to global surface air temperature, and about 9 months to global lower troposphere temperature. The correlation between changes in ocean temperatures and atmospheric CO2 is high, but do not explain all observed changes.
richardscourtney says:
September 4, 2012 at 10:59 am
“I could merely point out that your claim is the exact opposite of the claim from dikranmarsupial and Ferdinand which proves the data is not sufficient for a definitive indication.”
You are correct. It is. Which is why we must pull in other information to resolve the question.
That is why I point out that “we do have tie-breaking data to consider”, and proceed to support that statement in words, and mathematically in the succeeding comment.
dikranmarsupial says:
September 4, 2012 at 11:06 am
Arguments from authority do not impress. I have shown you where you are wrong in the past. I recommend you review that discussion.
“The problem is that the correllation only explains the variability in DIFF12 CO2, not its mean value, and it is the mean value of DIFF12 CO2 that gives rise to the long term increase.”
See the comment above. It rules out human culpability.
Richard, thank you for the clarification; it was an important point and I just wanted to be completely clear that we were in agreement. However, it would seem to me that if the natural environment were a net carbon sink it would be actively opposing the rise in atmospheric CO2, rather than causing it, as it is taking more CO2 out of the atmosphere each year than it puts in.
If natural uptake exceeds natural emissions, then it seems to me that the natural environment is putting downward pressure on atmospheric CO2 levels.
BTW, if you accept that the annual increase in atmospheric CO2 being greater than anthropogenic emissions establishes that the natural environment is a net carbon sink, then you have accepted the mass balance argument, as that isjust what the mass balance argument tells us.
Bart says:
August 31, 2012 at 6:15 pm
Phil. says:
August 31, 2012 at 11:28 am
I just noticed this comment wedged up there.
“The CO2 dissolved in the surface waters during the LIA which were at a lower temperature but also the partial pressure of CO2 during the LIA was about 60% of today’s.
Although I consider the ice core data highly suspect (because they are impossible to verify), it makes perfect sense that pCO2 of the atmosphere during the LIA would be less than today. It was colder then. When temperatures get colder, more goes into the ocean, in accordance with your relation
c = k*p
k increased, but the total c and p are constrained, so c had to increase while p decreased.
The total c and p are not constrained so your argument is flawed, Gtonnes of fossil Carbon have been added to the active system over that period. The change in temperature over the period in question is insufficient to increase the pCO2 to the amount observed.
Today, that c is coming back up again. It is displacing the c in today’s equation, so we can say dc/dt is greater than zero. Since, to the degree that “k” is actually constant,
k is not constant, it’s a function of temperature, (van’t Hoff equation as shown above, did you miss that too?)
Rising seawater which absorbed CO2 from an atmosphere which had a pCO2 60% lower than today’s and a temperature 2ºC lower will absorb CO2 when it reaches the surface because of Henry’s Law and the van’t Hoff equation.
Bart says:
September 4, 2012 at 10:59 am
The reason for the approximately 50% atmospheric rise is put down to rapid partitioning with the oceans. In the orthodox interpretation, the entire surface carbon reservoir is essentially fixed, and the added human inputs accumulate with little loss.
I thought we were there already before… That statement is wrong:
While the ocean surface is in rapid equilibrium (2-3 years) with the atmosphere, a 100% change in the atmosphere only gives a 10% change in total carbon level of the surface waters. That is the result of a small decrease in pH from the increasing CO2/bi/carbonate content in solution. Thus some 90% of the change stays in first instance in the atmosphere and is removed by much slower processes into the deep oceans and land vegetation.
Bart says:
September 4, 2012 at 9:06 am
That is the deciding factor: simple scaling matches both “b” and “p(t)” to “d” and “q(t)”. Simple scaling does not match “b” and “p(t)” to both “f” and “r(t)”.
Simple scaling does match “b” to “f” and “p(t)” to “r(t)”, without violating the mass balance or the 13C/12C ratio trend or the 14C/12C ratio trend and none of the other observations…
Again, the fast response and the trend are caused by different processes: the ocean surface and fast vegetation responses are the main source of the short term variability, while the trend is the result of the emissions and the much slower sink rates in the deep oceans and more permanent carbon storage by vegetation…
Bart says:
September 4, 2012 at 8:53 am
I think that Dikran said it all…
The two statements are equivalent: there are natural inputs and anthropogenic inputs. Both go into the sinks. A little bit is left over to accumulate. Yet, the first implies that the human contribution is responsible for the rise, while the latter implies that the natural input is responsible for the rise.
As I wrote at September 1, 2012 at 1:28 am:
Again, you don’t get it. It doesn’t matter which molecules are absorbed. It does matter that the total natural sink flux is larger than the total natural source flux. The human emissions are one-way additional, there are hardly any human sinks. The natural sources are NOT larger than the natural sinks, however you rearrange the wording”…
Thus the natural cycle is a net sink for CO2, not a source…
Sorry, made an error in the symbols…
Simple scaling does match “b” to “f” and “p(t)” to “r(t)”
must be:
Simple scaling does match “b” to “f” and “p(t)” to “q(t)”
With different scaling factors, as that are two separate processes: temperature changes are responsible for the bulk of the fast responses and the emissions are responsible for the bulk of the trend…
dikranmarsupial:
At September 4, 2012 at 11:27 am you say to me
No! I have not, and it does not.
The ‘mass balance’ argument assumes the system does not vary. This assumption of invariance is – to be polite – implausible. I refuse to accept that implausible assumption when it has no supporting evidence.
Once one accepts the possibility of natural variability then one has to accept that the mass balance argument is merely a circular argument. That so-called argument only informs that its user has adopted the implausible assumption.
Richard
Ferdinand Engelbeen says:
September 4, 2012 at 11:48 am
“While the ocean surface is in rapid equilibrium (2-3 years) with the atmosphere, a 100% change in the atmosphere only gives a 10% change in total carbon level of the surface waters.”
I appear to have overstated the case, while you have understated it. The IPCC estimates that some 30% of the atmospheric CO2 increase has gone into the ocean.It doesn’t really affect the point I was making to dikranmarsupial – the airborne fraction still does not depend on the morphology of the input.
Phil. says:
September 4, 2012 at 11:46 am
Read the comment here for a better understanding. Cooler temperatures mean more CO2 in the downwelling water. Lower atmospheric CO2 due to temperature implies an increase in the oceanic fraction. When that water rises in a warmer climate, it must release the CO2 it has stored.
Ferdinand Engelbeen says:
September 4, 2012 at 12:38 pm
“Simple scaling does match “b” to “f” and “p(t)” to “q(t)”’
You have to match both terms from the same source together. You cannot mix and match. Nature has no ability to separate the terms.
Bart says:
September 4, 2012 at 1:05 pm
“You have to match both terms from the same source together. You cannot mix and match. Nature has no ability to separate the terms.”
This is the nub of what I am saying. When you choose k1 such that b = d*k1, you also get a match between p(t) = k1*q(t) and conversely – if you choose k1 such that p(t) = k1*q(t), you also get a match with b = d*k1.
If the k1 you got from matching p(t) = k1*q(t) were smaller, such that b were significantly greater than d*k1, then there would be room for a significant human contribution. But, because everything matches up with just the temperature dependence included, you don’t need the human inputs, indeed, cannot accept them, as there is no room.
Bart says:
September 4, 2012 at 1:05 pm
I appear to have overstated the case, while you have understated it. The IPCC estimates that some 30% of the atmospheric CO2 increase has gone into the ocean.
On different time scales: 10% very fast in the ocean surface layer, 20% in the deep oceans at a much slower rate (combined e-fold time ~53 years). Essentially different processes with different time constants.
You have to match both terms from the same source together. You cannot mix and match. Nature has no ability to separate the terms.
It does, if the processes involved are different. The fast processes involves only 10% of the increase and most of the variability, the slower processes involve a small bit of the variablity and most of the trend…
Ferdinand Engelbeen says:
September 4, 2012 at 1:34 pm
“It does, if the processes involved are different. The fast processes involves only 10% of the increase and most of the variability, the slower processes involve a small bit of the variablity and most of the trend…”
It doesn’t work. That would require high-pass filtering of the temperature series, creating phase distortion at lower frequencies which is not observed.
Ferdinand Engelbeen says:
September 4, 2012 at 1:34 pm
“On different time scales…”
I don’t really want to argue this point as it is not germane to the topic at hand. But, you might review this:
And now, I really must concentrate on work…
Bart says:
September 4, 2012 at 1:29 pm
But, because everything matches up with just the temperature dependence included, you don’t need the human inputs, indeed, cannot accept them, as there is no room.
If we look at the oceans alone (similar points apply for vegetation), there are two separate processes involved: the ocean surface and the deep oceans.
The ocean surface reacts very fast on CO2 changes in the atmosphere and also very fast on ocean surface temperature changes. The latter with 16 ppmv/°C change in temperature. But that involves only 10% of the changes in the atmosphere.
The 90% of any CO2 injection (natural or human) stays in first instance in the atmosphere, increasing the CO2 level. That increases the sink rate near the poles. But that is a much slower process, only following the increase in total CO2 and the limited exchange fluxes between atmosphere and deep oceans. A change in temperature at the sink places will give a small (7%) change in sink rate, which is already small (~2 GtC/year). That hardly influences the CO2 levels in the atmosphere on short term. But it influences the integrated sink quantity over several years, while the surface temperature has no measurable influence on CO2 levels anymore after 2-3 years.
Thus yes, there is plenty of room for human inputs, as the fast response is mainly from the limited capacity ocean surface and the slow response is from the deep oceans with limited exchange rates, but these are net sinks, not CO2 sources…
Ferdinand Engelbeen says:
September 4, 2012 at 3:07 pm
“But that involves only 10% of the changes in the atmosphere.”
Widely acknowledged 30% – see above.
“Thus yes, there is plenty of room for human inputs, as the fast response is mainly from the limited capacity ocean surface and the slow response is from the deep oceans with limited exchange rates…”
You cannot mix and match. It’s a long stretch in the first place, given the incredibly excellent agreement of the scaled trend in temperature with the trend in the CO2 rate of change. But, the data are inconsistent with high pass filtering, which would give an additional phase advance at low frequency, and phase distortion in the transition region. There is nothing like that evident in the data.
“…but these are net sinks, not CO2 sources…”
No evidence at all for that.
I think we have run out of things to say.
Bart says:
September 4, 2012 at 5:12 pm
Widely acknowledged 30% – see above.
Widely acknowledged (and measured as the increase of DIC over the past 20 years at a few places), that the seawater surface follows the atmosphere with not more than 10%, with a rapid adjustment time of 2-3 years. If the oceans were fresh water, it was only 1%, due to the low pH. The buffering by carbonate salts increases that to ~10%, due to a higher pH. That is called the Revelle factor or buffer factor. Look that up…
The rest is going into the deep oceans with an adjustment time of ~50 years.
You cannot mix and match. It’s a long stretch in the first place, given the incredibly excellent agreement of the scaled trend in temperature with the trend in the CO2 rate of change.
All of your reasoning is based on the premisse that only one overall process influences the temperature-CO2 changes, but that is wrong.
The fast oceans surface mixing process responsible for the variability only works on 10% of the increase, its long term trend doesn’t change much after 2-3 years, at a maximum of 16 ppmv/°C. The longer term deep ocean processes hardly influence the year by year variability, but are persistent over the years, again with an overall maximum of 16 ppmv/°C. Thus no matter which ocean process is involved, the maximum influence of temperature on CO2 levels by the oceans is 16 ppmv/°C. But that are two different processes each with their own adjustment rate.
Any more deep ocean upwelling (from the past) or downwelling (of the present) is a process that is independent of the current temperature variations, except for the short to medium term influence of temperature at 16 ppmv/°C. Thus an increase of 70 ppmv in only 50 years can’t be caused by the current temperature change. The consequence is that the same factor for the past 50 years for a short and medium response of CO2 to temperature is pure coincidence.
The other fast to medium term processes in land vegetation work the opposite way out, thus decreasing the 16 ppmv/°C to ~8 ppmv/°C over very long term.
No evidence at all for that.
Proven by millions of seawater pCO2 samples over decades: a net sink of 2 GtC/year.
And a consequence of the mass balance: with 8 GtC/year of human emissions and a 4 GtC/year of increase in the atmosphere, the overall natural sink rate is 4 GtC/year. Of which 1.2 GtC/yr goes into land vegetation (based on the oxygen balance) and 0.8 GtC into the ocean surface layer (based on the buffer factor). The rest into the deep oceans, as other natural sinks are either too small or too slow.
Richard wrote: “The ‘mass balance’ argument assumes the system does not vary.”
No, this is not correct, the mass balance argument makes no such assumption, and it is easily demonstrated that this is not the case. The magnitude of the net environmental sink inferred by the mass balance argument exhibits considerable year-to-year variability and has been slowly gaining in magnitude for the last fifty years. If the mass balance argument assumed the system does not vary this would be impossible. See this figure from Ferdinand’s website (similar results have been given in the litterature) http://www.ferdinand-engelbeen.be/klimaat/klim_img/dco2_em.jpg
We have agreed that the natural environment is a net carbon sink, so please explain how the natural environment is causing the observed rise in atmospheric CO2 while at the same time taking more CO2 out of the atmosphere each year than it puts in.
dikranmarsupial:
Your post at September 5, 2012 at 12:54 am is addressed to me and begins
My statement is correct and your response displays a complete failure of logic. I explain this as follows.
The fact that there is year-to-year variability does not change the fact that invariance of the system has to be assumed over time for the mass balance to indicate any specific change as a ’cause’ of long-term variance of CO2 in the atmosphere.
The mass balance is accountancy applied to CO2 entering and leaving the atmosphere. As proponents of the mass balance argument often assert, it is similar to accountancy applied to a bank account. So, I will use that analogy to demonstrate your misunderstanding.
A person has an income which is mostly his salary that his employer pays into his bank account each month. The bank account fluctuates as the salary is paid in each month and the person makes withdrawals to pay his living expenses. Thus, the account fluctuates but over time it is constant. (This is similar to the seasonal fluctuation varying the CO2 in the atmosphere).
Then the owner of the bank account obtains additional income; for example, he is poor so the government gives him a Winter Fuel Allowance (this happens in the UK). Assuming no other change, then the bank account starts to rise over the following years. (This Winter Fuel allowance is similar to the anthropogenic CO2 providing an input of CO2 to the atmosphere).
But there may be other changes. For example, the addition of the Fuel Allowance to his income increases his total income, and this increase may make him eligible for payment of income tax or make him ineligible for receipt of invalidity benefit. Hence, the addition of fuel allowance may result in his bank balance decreasing over time. Alternatively, he may not spend his Fuel Allowance on needed fuel but, instead, he chooses to invest his Fuel Allowance to gain a return on it: in this case his bank balance will increase by MORE than the amount of the Fuel Allowance over time.
Similarly, it cannot be known what effect addition of the anthropogenic CO2 (i.e. Winter Fuel Allowance) will have on the CO2 in the atmosphere (i.e. the bank balance) because the total system of the carbon cycle is not known. We do know it has some effects (e.g. additional CO2 in the air increases biological activity which sequesters CO2 from the air) but all its effects are not known. Therefore, the system’s response to the anthropogenic emission cannot be known.
Furthermore, in the above analogy the system does not vary over time except for effects of the Winter Fuel Allowance (i.e. the anthropogenic CO2). In reality, we know it does. So, we need to extend the analysis.
Consider that there are changes to income tax levels and/or rates (e.g. CO2 sequestrations) then the proportion of the salary which is paid into the bank account (i.e. the amount of CO2 input to the atmosphere) will vary. This will happen for many reasons such as a change of government (i.e. a variation in CO2 upwelling from deep ocean) and it will alter the increase or reduction of the bank balance (i.e. the CO2 in the atmosphere).
It is not known if the change has happened. But it will directly affect the bank balance (i.e. CO2 in the atmosphere) and the effects of the Winter Fuel Allowance (i.e. the anthropogenic CO2) on the bank balance. The change may alter whether the Fuel Allowance makes him eligible for payment of income tax or makes him ineligible for receipt of invalidity benefit. Hence, the external change may cause the bank balance (i.e. CO2 in the atmosphere) to increase or decrease whether or not there was a Winter Fuel Allowance (i.e. the anthropogenic CO2), and the Winter Fuel Allowance may increase or may reduce the effect of the external change on the bank balance.
However, one can
1.
mistakenly assume the system which determines the bank balance does not change over time,
2.
assess the change in the bank balance and, thus,
3.
decide the Winter Fuel Allowance causes the observed changes in the bank balance.
In reality, as the analogy describes, the unaccounted – and unknown – changes of the system may be entirely responsible for the observed rise in atmospheric CO2 and the effect of the anthropogenic emission may have been to increase or to reduce the observed rise. In the absence of adequate knowledge and understanding of the carbon cycle then the cause of the observed rise in atmospheric CO2 cannot be known. And we lack both the knowledge and the understanding of the system of the carbon cycle.
Importantly, the dynamics of the seasonal variation in atmospheric CO2 indicate that the system of the carbon cycle can easily sequester all the emitted CO2 (both natural and anthropogenic), but the observed rise in the atmospheric CO2 indicates that not all the total emission is being sequestered over time. At issue is why not all the total CO2 emission is sequestered when we know the system can – and could be expected to – sequester all of it: we lack both knowledge and understanding of the carbon cycle system sufficient to determine why not all the total CO2 emission is sequestered. (This is like observing that the balance in the bank account is rising because the electricity company does not take the money it is owed although it has a Direct Debit facility for taking the money, and we don’t know why the electricity company is not taking the money).
You conclude by asking me
I have repeatedly explained this in different ways in this thread. I have again tried in this thread. The problem arises from your mistaken assumption that the system does not vary over time. As I said, that is an implausible assumption.
I hope this answer is adequate.
Richard
Richard, I also like banking analogies. The problem I have with yours is that it is difficult to tell what quantities in the analogy relate to which quantities in the carbon cycle. Here is an analogy where this is made explicit.
Say I share a savings jar with my wife, and it is guarded by a cadre of loyal ninja, so I know that nobody can make withdrawals or deposits other than my wife and I. My deposits represent anthropogenic emissions, and I put 8 euro in the jar each month. I make no withdrawals as at the moment, which would represent anthropogenic uptake, as mankind is not at the moment performing any meaningful amounts of carbon sequestration. My wifes deposits represent natural emissions from all sources (whatever they are, whatever mechanisms are involved); she puts in 90 euros a month. Her withdrawals represent natural uptake into all natural sinks (whatever they are, whatever mechanisms are involved). Her withdrawals are 94 euros a month.
I think we can both agree that in this example, my wife is taking four more euros out of the jar each month than she is putting in, and so the rise of 4 euros a month in the balance is due to my activities, and is being opposed by hers.
Say I didn’t know that she deposited 90 euros a month and took out 94 euros a month. I would still know that she is spending 4 euros a month more than she saved if I observe that the balance is rising by four euros a month less than I am putting in.
The mass balance argument is similar. We don’t need to know the value of natural emissions or natural uptake to know that the natural environment is a net sink. All we need to do is observe that the annual increase in atmospheric CO2 is always less than anthropogenic emissions.
Now you can say that this analogy is too simple, in which case, feel free to extend it, provided you specify where the extensions map on to the carbon cycle. However, since the analogy already includes all natural sources and sinks and anthropogenic sources and (lack of) sinks, what else is there?
Ferdinand Engelbeen says:
September 5, 2012 at 12:26 am
“That is called the Revelle factor or buffer factor. Look that up…”
Indeed. It is the subject of the paper I linked. And, the correct figure is 30%.
“All of your reasoning is based on the premisse that only one overall process influences the temperature-CO2 changes, but that is wrong.”
The data show it is correct. There is no indication of separate processes in the dominant respose. The dominant response acts uniformly across frequency such that the derivative of CO2 matches temperature.
“Proven by millions of seawater pCO2 samples over decades: a net sink of 2 GtC/year.”
You are mistaken. Oddly, you had agreed at one point with what I explain to dikranmarsupial below, but then you slid back into misunderstanding.
dikranmarsupial says:
September 5, 2012 at 12:54 am
“No, this is not correct, the mass balance argument makes no such assumption, and it is easily demonstrated that this is not the case.”
It is easily demonstrated that it is the case. It all comes down to how powerful the sinks are relative to the sources. The faux mass balance argument depends on the sinks being weak and flaccid. The data show they are not.
This really is a trivial feedback problem. It amazes me you guys, and apparently many others, can be so far removed from reality.
dikranmarsupial:
re your post at September 5, 2012 at 8:47 am
OK, I tried. But you have ignored what I said (again). Believe whatever you want, but I see no point in my again and again explaining the same realities in different ways merely for you to ignore my efforts.
Richard
Richard, no problem, thank you for the discussion.
Bart says:
September 5, 2012 at 9:20 am
Ferdinand Engelbeen says:
September 5, 2012 at 12:26 am
“That is called the Revelle factor or buffer factor. Look that up…”
Indeed. It is the subject of the paper I linked. And, the correct figure is 30%.
It is indeed the subject of the paper but apparently you didn’t read the paper because it explicitly states: “Revelle and Suess calculated that R had a value of about 10. Because of an improved global data set we know that the Revelle factor currently ranges from about 9 in low-latitude tropical waters up to 15 in the southern ocean off Antarctica”
Bart wrote “It is easily demonstrated that it is the case. It all comes down to how powerful the sinks are relative to the sources. The faux mass balance argument depends on the sinks being weak and flaccid. The data show they are not.”
No, that is not correct. The mass balance analysis, when applied to the observations, shows that the natural environment is a net carbon sink, and that the difference between total natural emissions and total natural uptake is increasing. However this could be because natural sinks are strengthening, or because natural sources are weakening, or both natural sources and sinks are strengthening, but sinks more so than source, or that both natural sources and sinks are weakening, but sinks less so than sources. The mass balance argument does not tell you WHY the gap is widening, it just shows that it is.
As it happens, if you read the IPCC report, you will find that the mainstream view is that both sources and sinks are strengthening, but the sinks more so than the sources. Thus your assertion regarding the assumption that the sinks being weak and flaccid is the exact opposite of the mainstream view.