Tuesday
Apr142015
by 
Bishop Hill
Bishop Hill The Salby lecture
Apr 14, 2015 Climate: Sceptics Climate: carbon budget Murry Salby's recent lecture in London can now be seen on YouTube.
Apr 14, 2015 Climate: Sceptics Climate: carbon budget
Reader Comments (179)
It's all very well for rabbitses to defend their burrow mortgage payments and point at this or that aspect of the science which may or may not be solid, but there are giant holes in the narrative deeper than their own burrows.
James Lovelock in the Guardian on Climategate and its implications
on CRU scientists
I was utterly disgusted. My second thought was that it was inevitable. It was bound to happen. Science, not so very long ago, pre-1960s, was largely vocational. Back when I was young, I didn't want to do anything else other than be a scientist. They're not like that nowadays. They don't give a damn. They go to these massive, mass-produced universities and churn them out. They say: "Science is a good career. You can get a job for life doing government work." That's no way to do science.
I have seen this happen before, of course. We should have been warned by the CFC/ozone affair because the corruption of science in that was so bad that something like 80% of the measurements being made during that time were either faked, or incompetently done
on computer models
I remember when the Americans sent up a satellite to measure ozone and it started saying that a hole was developing over the South Pole. But the damn fool scientists were so mad on the models that they said the satellite must have a fault. We tend to now get carried away by our giant computer models. But they're not complete models. They're based more or less entirely on geophysics. They don't take into account the climate of the oceans to any great extent, or the responses of the living stuff on the planet. So I don't see how they can accurately predict the climate.
on predicting temperatures
If you look back on climate history it sometimes took anything up to 1,000 years before a change in one of the variables kicked in and had an effect. And during those 1,000 years the temperature could have gone in the other direction to what you thought it should have done. What right have the scientists with their models to say that in 2100 the temperature will have risen by 5C?
The great climate science centres around the world are more than well aware how weak their science is. If you talk to them privately they're scared stiff of the fact that they don't really know what the clouds and the aerosols are doing. They could be absolutely running the show. We haven't got the physics worked out yet. One of the chiefs once said to me that he agreed that they should include the biology in their models, but he said they hadn't got the physics right yet and it would be five years before they do. So why on earth are the politicians spending a fortune of our money when we can least afford it on doing things to prevent events 50 years from now? They've employed scientists to tell them what they want to hear.
on scientists
Sometimes their view might be quite right, but it might also be pure propaganda. This is wrong. They should ask the scientists, but the problem is scientists won't speak. If we had some really good scientists it wouldn't be a problem, but we've got so many dumbos who just can't say anything, or who are afraid to say anything. They're not free agents.
http://www.guardian.co.uk/environment/blog/2010/mar/29/james-lovelock
I recommend this BBC Horizon programme which uses comedian David Mitchell to ridicule the science of dark matter / energy and its cheerleaders.
http://www.bbc.co.uk/iplayer/episode/b05n8jqs/horizon-20142015-10-dancing-in-the-dark-the-end-of-physics
Watch for results from the LHC which will suggest the existence of dark energy, extra dimensions, parallel universes because results don't match expectations. Something else just disappeared down the rabbit hole. It's the same game. Add another factor that explains why you're wrong, shovel more coal into the gravy train and chase it down. Follow that unicorn, driver. It's got my name on it.
Before exhaling further, Shub and dung should compare the mass of biospheric carbon with the amount in carbonate rocks: now as in the Creteaceous , the biosphere weighs less than the amount of limestone in Crete, let alone Albion.
Russell, any clown who claims an increase in CO2 in the atmosphere would suck life out of the biosphere should make the comparison.
Please watch the Horizon programme and note the comedy music all the way through. They don't only rip the p* out of the science. They also rip the p* out of the scientists.
This would be a wonderful exercise for climate science. It would be SO easy.
Shub,
I said no such thing. Try reading it again or - as is more likely - keep repeating something that is not true.
Eli
"Now some, not Eli to be sure, are quite impressed with Salby and his take that the rise in CO2 comes from the oceans. Assume this to be true, then one would expect that the increase in CO2 in the southern hemisphere, which is mostly ocean, would lead that in the northern hemisphere, which is mostly land,, but in fact, the opposite is true and the lag matches the interhemispheric mixing time."
So are you claiming that the response time constants are different in the two hemispheres? I find that idea very, very strange. How do the CO2 molecules know where they are? And do we now have second-order effects in play?
Eli
"Others, again, not Eli to be sure, assume that the rise in CO2 comes from the oceans and not from combustion of fossil fuels. Burning of fossil fuel consumes oxygen, and hey, what do you know, the concentration of oxygen in the atmosphere is falling. Of course, since oxygen makes up 20% of the atmosphere and the increase in CO2 concentration has only been tens of ppm in the last couple of decades, the decline in oxygen concentrations would also be small in absolute numbers, but as Ralph Keeling has shown the decline is consistent with the rise in CO2 concentrations coming from burning fossil fuels."
O2 levels have been declining for a while; to convince me I'd have to see a negative, second-order effect.
Man-made climate change is the biggest fraud ever inflicted on us.
The IPCC came up with the idea of an earth energy balance and they produced a diagram to show energy transfers. This diagram is wrong and it has now been removed from the climate change debate.
The diagram shows that more energy arrives at the earth's surface than arrives from the sun. The reason for this is that it is assumed that the Stefan-Boltzmann law applies to the earth's surface and in the atmosphere. They assume that the earth's surface radiated more energy than it does and if this is true the earth's surface temperature would be low. To overcome the error the greenhouse effect was invented. This says that energy is reflected back to the earth's surface and the result is that energy is created from nowhere.
The politicians are such fools that they cannot work this out, but why would they when they make massive amounts of money from it.
The O2 argument is equally weak. Reduced or increased photosynthesis sends the oxygen upwards and the carbon downwards, both on land and in the ocean. It could be many centuries before the two meet up again. Short term changes may be meaningless.
Second, the stoichiometry of redox reactions oxidizing C/reducing O2 in the environment is not fixed either. Did one mole of CO2 arise from
C(coal, carbohydrate) + O2=CO2, or
CH4 (methane from any sources) + 2 O2=CO2 + 2 H2O ??
Bugs Rabett knows this very well, and aTTP ought to by now. But if either of them were told that next year's salary was going to be, very roughly, $/€/£ 1 million, +/- 1 million, then they would probably start getting a little bit antsy.
I'm not entirely happy with Salby either, for several reasons. He's indulging in a bit of what the alarmists usually do every day.
The data still provides plenty of room for everybody to be wrong.
And the truth will likely be somewhere in between. :)
Well, at least Ken Rice is not one of those 'many dumbos who just can't say anything or who are afraid to say anything'. But is he a free agent?
Perhaps he's buying his freedom touting his soul and his science on skeptical blogs.
======================
Good to see he's run off without answers.
Anyone know who removed and disabled the comments on the Youtube version of the video? Strange, as it was going so well and there was some real momentum building. Almost as if someone didn't want to allow any criticism of the presentation, but I'm sure that can't be right, can it?
If you were able to, I would most likely say it was you.
Re no comments on Youtube - not quite sure why, but there's plenty of discussion on Wattsup .
Capell: So are you claiming that the response time constants are different in the two hemispheres? I find that idea very, very strange. How do the CO2 molecules know where they are? And do we now have second-order effects in play?"
Nope, just that if the oceans were the largest source of the excess CO2 you would see the concentration in the Southern Hemisphere being larger than that in the North, e.g. if Salby were correct the CO2 concentration in the Southern Hemisphere would lead that in the Northern.
Capell:O2 levels have been declining for a while; to convince me I'd have to see a negative, second-order effect."
Since O2/N2 has only been measured since ~1990, Capell would have a hard time, but yeah maybe you could see that in the ~25 years that the data is good enough
http://ossfoundation.us/projects/environment/global-warming/myths/images/atmosphere/ralph-keeling-curve.png
Eli will mark you down as convinced in that case
Eli
Bigger ocean area, bigger CO2 source, bigger CO2 sink . . .
O2/N2 has only been measured since ~1990 . . . wait another 25 years . . .well, what's your point then?
I'll mark you as a silly buntie.
Michael Hart: When the CO2 mixing ratio increases by 100 ppm, the concentration goes from 300 to 400 pm. The process will consume 100 ppm of Oxygen molecules, and the oxygen mixing ratio will go from 200000 ppm to 199900. This is harder to measure, but Ralph Keeling has done it.
If Salby is right then there should be NO change in the oxygen mixing ratio because volcanoes are not the result of combustion. The Ralph Keeling curve is exactly evidence that increase in CO2 is a result of combustion.
So think of this as a skeptic test. At the start of this thread commenters were demanding evidence. Eli provided strong evidence. Why are you denying it.
Yes, I'd quite like to know the answer to this too.
I was wondering if somebody could explain IPCC AR5 figure 2.1(b) to me. It is a graphical presentation of "Instantaneous growth rates for globally averaged atmospheric CO2" expressed in ppm/year.
http://www.climatechange2013.org/images/figures/WGI_AR5_Fig2-1.jpg
The figure looks almost identical to RSS data set and absolutely nothing like human emissions from burning fossil fuels. The highest increase in any year was 1998. This seems like to much of a coincidence to me and on the surface would support what Salby is saying. Am I missing something?
Dave O,
Well, that figure is illustrating the problem with Salby's analysis. The bottom panel shows the growth rate (ppm/yr). The variability is indeed driven by temperature. The global average temperature is not constant over a single year because the two hemispheres aren't the same. The global average temperature is also varies due to various internal cycles like ENSO events. Atmospheric CO2 does respond to changes in temperature, so 1998 does indeed show a response to the large ENSO event. However, if you look at that lower figure there is an offset of 1ppm/yr to 2ppm/yr. That's the bit that is us. In other words, without our emissions we would expect the growth rate to vary but to average to 0. Additionally, Salby's analysis correlates growth rate with temperature. However, a correlation is insensitive to an offset (the 1ppm/yr to 2ppm/yr) so all his analysis does is illustrate that there is a correlation between temperature and CO2 growth rate on short timescales, but can say nothing about what is causing the offset (the 1ppm/yr to 2ppm/yr which is us).
I saw my name mentioned a few times here...
I have listened the different items which Dr. Salby proposed in his different lectures and was present last year in London when he spoke in the Parliament.
There are several important points where he goes wrong:
- The mass balance:
Humans emitted about twice the amounts as measured as increase in the atmosphere.
That implies that nature as a whole is a net sink over at least the past 55 years of accurate data.
No matter how you torture the data, it is impossible that nature had much contribution to the increase, or the increase in the atmosphere would have been larger than the human contribution alone.
Only the increase in temperature since the LIA gives an overall contribution of ~6 ppmv out of the oceans (that is the equilibrium change between oceans and atmosphere for 0.8°C warming).
- The phase analyses:
His phase analyses shows a good correlation between temperature (rate of change) and CO2 rate of change with a lag. That only shows the cause of the variability. That doesn't say anything about the cause of the increase if you have, as in this case, two influences: temperature with a huge variability and little trend and human emissions with no measurable variability (in the atmosphere) and a huge trend. As the mass balance shows: all variability is in the sink rate, not the source rate...
- The residence time:
All "proof" from rapid decay of some extra CO2 injection from Salby and several others is based on the residence time: that is the average time any CO2 molecule resides in the atmosphere before being exchanged with a CO2 molecule from another reservoir. That doesn't change the total amount of CO2 in the atmosphere and says absolutely nothing about how long it takes to reduce an extra shot of CO2 above equilibrium back to equilibrium. The residence time is about 5 years, the e-fold decay rate of extra CO2 is over 50 years...
It is like comparing the turnover of capital/goods through a factory (residence time) to the gain or loss of the same capital at the end of the year...
For more discussion, see WUWT...
For more arguments why humans are responsible for the CO2 increase, see my web page:
http://www.ferdinand-engelbeen.be/klimaat/co2_origin.html
"If Salby is right then there should be NO change in the oxygen mixing ratio because volcanoes are not the result of combustion. The Ralph Keeling curve is exactly evidence that increase in CO2 is a result of combustion."
Doesn't follow. If you oxidize X amount of carbon to CO2 you would expect a corresponding reduction in oxygen. Fine, but that says absolutely nothing about what proportion of the net annual increase of CO2 in the atmosphere is due to that process alone. Didn't they teach critical thinking as part of your illustrious education?
No need to mention the massive assumptions regarding biota and all other oxidization processes going on across the planet, as a quintessential rabbit you'll step on any old rusty gin. Back in the day my grandfather ran 2,500 of those on contract and had a hard time keeping up with the freight to local butchers.
BTW, where does Salby say the increase is coming from volcanoes? Admit it; you haven't even looked at his arguments let alone considered the phase relationship of the lag spectrum, which being a mere rabbit you probably won't see the significance of anyway. That requires a little more than 2+2=5 bob-tailed logic, even with an increased carrot ration to see in the dark.
You have provided no evidence. Like 97% of climate science, merely alarmist conjecture. The uncertainties are monumental and piled one on another. No surprise the fag packet one chimed in, perhaps he thinks you're still dissing Plimer too.
Myxomatosis was introduced to the big rusty red continent in the southern hemisphere (and the UK) years ago, no use for gin traps thereafter. Or so you'd think. Indeed as a kid like many others at the time, I bred rabbits for pocket money (Californian bucks and New Zealand does, perfect for selling on via the local rabbit farm). A while ago there was a hint the industry was making a comeback in the UK. Looks like the demand is still there - 3,000 tonnes of dressed meat per year is a lot of bunnies.
Should you wish to kit out you lab with a few gin traps for self-discipline Eli, I can probably rustle up a few working examples from somewhere. "Defiance" was a good brand IIRC.
"His phase analyses shows a good correlation between temperature (rate of change) and CO2 rate of change with a lag."
Wrong, didn't listen and take it in either.
Anonymous,
From Janice (I did listen to the first 10 minutes, that was more than enough to be sure that it were the same arguments).
At 7:20 in his speech:
"Human CO2 and Net CO2 Emission records are incoherent. That is, net global CO2 emission evolves INDEPENDENTLY OF HUMAN EMISSION."
10:05 – Correlation of .93 (net global CO2 emission and surface properties).
where "surface properties" in general is temperature and drought.
10:55 – Temperature (the main surface property driver) correlation: .80.
Further (I have repeatedly listened to it now):
11:05 – Integrating thermally-induced CO2 emission backward, i.e., subtracting therm. CO2 for each preceding year (year x-1) from current CO2 (year x), repeating this going back to 1980, gives an accurate estimate of net natural CO2 (since most net natural CO2 emission is thermally induced).
Here he assumes that the full CO2 year by year increase (variability + offset) in de/increase is thermally induced (thus all natural), not easily to decipher, but that is what he really does.
Of course that shows that the whole in/decrease is from natural causes as he simply uses not only the variability but includes the offset, while the offset of the curve is for 95% what humans introduced...
Englebeen
Your web pages on this subject are very good.
On the subject of residence time you 'vote' for five years, close to Salby's figure of 8 years from the post NTBT decay of N14. If that's the case then after five residence times (25 years, 40 years if you assume 8 years residence time), assuming you dump human CO2 into the atmosphere at a constant rate, you reach saturation in the atmosphere from that source at about five times the annual tonnage dump rate. This is exactly the same as adding radioactive material all with the same half life to a single radioactive dump and determining the radioactivity from the total dump.
If you stop adding radioactive material to the dump, the total radioactivity will decay and after five half lives it will be close to zero.
Of course with atmospheric CO2 this analogy might fail because whereas radioactive decay is a always constant unaffected by the surroundings (unless, of course they're highly radioactive), but the CO2 has not completely disappeared from the total earth system, it's just gone somewhere else and it may be that that sink will saturate - or not.
But, if you stop adding CO2 to the atmosphere and the sinks remain the same, it was disappear after five residence times. The system can't tell the difference between 'natural' CO2 and anthropogenic CO2.
Capell,
No, you need to read what Ferdinand said again (and he said it extremely well - I may have to use it myself one day). I'll even repeat the key point
Capell,
There are two problems with the residence time, which renders then unsuitable to predict the decay of an extra injection of CO2 in the atmosphere.
1. Residence time and e-fold decay rate are the same if the subject is reduced one-way. That is the case for radio-activity and for e.g. the use of CFC's in the atmosphere, which didn't exist in pre-industrial times and slowly disappear in the deep oceans and by UV light in the stratosphere.
In the case of the bulk of CO2 (99% 12CO2), the residence time indeed is ~5 years, but that is only a cycle: what is removed in one season is coming back in the next season and nothing happens with the total quantity in the atmosphere: 20% of all CO2 in the atmosphere is simply exchanged with CO2 from other reservoirs. The residence time = amount in the atmosphere / throughput = 800 GtC / 150 GtC/year = 5.3 years.
The main exchanges in this case are temperature driven.
The only way that an extra injection of CO2 in the atmosphere can be removed is if there is a difference between the inputs and outputs over a full cycle. The main driver in that case is the increase of the CO2 pressure in the atmosphere: more pressure increases the output into the oceans (and plant stomata) and decreases the input from the ocean upwelling zones. That is a complete different "residence time" for an extra amount of CO2 above the temperature driven equilibrium. To make a differentiation, we may call it the e-fold decay rate: In that case the formula (for a linear process, which the CO2 cycle seems to be) is driving force / result = 110 ppmv / 2,15 ppmv/year = 51.3 years. Or a half life time of ~40 years for an excess amount of CO2 above equilibrium.
Two completely different decay rates. One that says that from the original "human" CO2 molecules 20% / year disappears in other reservoirs (rather permanently in the deep oceans), the other how long it will take to remove the extra CO2 injection from humans as mass out of the atmosphere.
Many skeptics, including Salby, Humlum, Pettersson,... use the residence time in their calculation, which thus has nothing to do with the time needed to remove some extra CO2.
On the other side, the IPCC uses much longer decay rates, according to the Bern model (a composition of several decay rates into different reservoirs), but that includes a fast saturation of the deep oceans, for which is not the slightest sign.
2. The 14C decay rate:
That is a special case: the 14C bomb spike decay rate could be a nice tracer for the decay rate of an extra injection of total CO2, but again, while its decay is partly in the deep oceans to return over ~1000 years (if not completely diluted by the rest of the ocean waters). What returns today is the 14C level of ~1000 years ago which is not zero, but still 45% of the 1960 spike.
For the excess CO2 already in 1960 we have the following situation: ~41 GtC goes into the deep with ~99% 12CO2 and 100% of the 14C spike (10^-22 in mass of 12CO2...), but what comes out is ~40 GtC (97.5% in mass) again with ~99% 12CO2 and only 45% of the 14C spike.
See: http://www.ferdinand-engelbeen.be/klimaat/klim_img/14co2_distri_1960.jpg
That makes that the e-fold decay rate of the 14C bomb spike is at least a factor 3 shorter than for an excess 12CO2 spike...
Engelbeen
Keeping the labelling 1 and 2 (the latter being the 14C rate) for the two processes you see operating at any one time in this exchange between atmospheric CO2 and the various CO2 sinks, I can well understand the bulk concentration process you describe in (1) as that was the modification/saturation of the sinks that I mentioned in my previous post.
But let's consider what happened in the year 1963, the year of the test ban treaty. We know that a certain proportion of the 14C CO2 molecules were swept from the atmosphere into the carbon sinks and never returned. As you postulate, reasonably, they could have been captured into some deep-ocean circulation. Equally, they may have been captured into biomass. But also in that 1963 atmosphere there would have been 'natural' CO2 molecules and anthropogenic molecules. They didn't have a 14C label, but isotropically they were identical to the 14CO2 molecules. I can't imagine for one moment that you'll postulate any different capture process for these molecules, so some of these molecules would have disappeared into the same sinks as the 14CO2 molecules in the same proportion as the 14CO2 molecules 'suffered'.
Now move forward to some time in the future. Those CO2 capture process still occur, but since the overall CO2 concentration levels have changed in your model (2) the bulk CO2 residence time has been changed by virtue of the greater concentration in the system. The annual source/sink interchange increases the residence time to what we observe (variously) today as somewhere between 50 and 200 years. But the 14CO2 are still being flushed from the system at the same old residence time of 8 years. The exponential decay of 14CO2 molecules has carried on, unchanged in logarithmic slope for nearly 50 years - it's what first-order, linear differential equations do. And it still applies that 14CO2 molecules are isotropically the same as natural 12CO2 molecules and anthropogenic 12CO2 molecules, so why should we think that the present day residence time is anything other than that of the 14CO2 molecules?
I am not saying, by the way, that there cannot be multiple residence times operating at the same time. There may be (almost certainly are) several different capture processes going on at the same time all with different time constants.
Engelbeen
Just a minor point: adding more and more anthropogenic CO2 to the atmosphere must, of course, dilute the 14CO2 proportion, but this effect will be very small.
Engelbeen
I've just discovered the lengthy discussion on this subject on the WUWT blog. That's proving very useful.
Ferdinand, that's science. You have Salby's claim (at least one of them), and you have a counter-explanation. The facts can be weighed up and an actual decision can be made. Ironic, that you if you ask for an explanation like this, you should be banned from a blog.
The larger point is, you should be able to explain why in your words, if you've come to believe something or disbelieve it. If the best you can do is copy and paste others' explanations or emit grunts, you are no better than the person asking the questions.
Capell,
The main difference is in the deep oceans.
What goes into the ocean surface is about 10% of the change in the atmosphere, due to ocean carbon chemistry. That is for all isotopes. As the exchange rate between ocean surface and atmosphere is very rapid, the ocean surface was already saturated with the extra 14C and only is an extension of the atmosphere in the sink rate.
The biosphere carbon cycle is also modest: some 60 GtC is going in and out per year, where most is seasonal growth and decay. That too is rapid and less than 10% of the atmosphere. The more permanent storage is much smaller: ~1 GtC/year or ~0.1%/year of the atmospheric CO2 content.
Thus although there are huge exchanges, the distribution of changes in isotopic ratio and/or some total CO2 mass changes in the atmosphere are distributed over the ocean surface and vegetation, but that has little influence on the isotopic composition or mass of CO2 in the atmosphere.
Different story for the deep oceans: what goes into the deep oceans is the result of the CO2 pressure in the atmosphere and isotopic composition of 1963 to start with the maximum 14C peak. There is some difference in absorption speed between the isotopes (which makes that the isotopic composition changes at the air-water border and reverse), but let us forget that for the moment.
The CO2 pressure above the temperature controlled equilibrium at that time (~25 ppmv) pushed 1 GtC extra in the deep ocean sinks and 100% of the 14C peak value, in total ~41 GtC going into the deep, of which ~99% 12CO2, ~1% 13CO2 (somewhat diluted already by fossil low-13CO2) and a trace of 14CO2.
At the upwelling site, some 40 GtC comes back in the same year, again ~99% 12CO2, ~1% 13CO2, but somewhat richer in 13CO2 than what did sink. But only with 45% of the concentration of the 14CO2 peak which did sink near the poles.
Do you see the problem? From the 12CO2 mass, some 97.5 % returns the same year, from the 13CO2 mass some 98% returns the same year, but from the 14CO2 trace "mass" only 97.5 x 45% returns the same year, less than halve what was absorbed.
That makes that the disappearance of any 14CO2 peak out of the atmosphere into the deep oceans is much faster than for a total CO2 peak, as most of the main two isotopes return to the atmosphere with near the same quantity in the same year... No matter if the extra CO2 peak was caused by volcanoes or humans...
Ferdinand,
No, he labours the point: The "value in the blue curve" is the thermally induced component only. Total net emission is the green curve. We're not told how the blue curve was derived however.
The original claim was that CO2 concentration evolves as the integral of temperature. That comes from the phase analysis (described later in this video). Or to put it another way, the rate of change of CO2 is essentially proportional to temperature - not the rate of change of temperature as you stated. Temperature in this context means some shift over arbitrary time, the point being that a wide spectrum of lag times is involved which we cannot discern beyond the obvious seasonal cycle. It is not dT/dt.
Nowhere does Salby claim "the whole in/decrease is from natural causes". Indeed, the entire lecture is about estimating the split between thermal and anthropogenic induction. He points to the rate of increase of CO2 after 2002 remaining unchanged despite marked <u>acceleration</u> of anthropogenic production.
My annual signal plot of ML at monthly resolution shows that the Pinitubo/Hudson cooling and 1998 El Nino impart massive uncertainty on that observation before 2002. However, increased human output shows up after 2002 but does NOT accelerate. The noise is not sufficient to mask the acceleration over the following decade. Here is Salby's slide. Here is my plot with his claimed anthropogenic emission acceleration rates superimposed.
I could do an SD to characterise the noise, a linear trend etc. over the two periods but there seems little point. Assuming Salby's emissions to ppmv conversion is in the right ball-park, divergence over the far less noisy latter period is stark. There is essentially zero acceleration.
You appear to be at the opposite extreme by claiming the offset is ~95% human induced. Why then does accelerating fossil fuel use for over a decade not show up? Given temperature has increased since the LIA, one would reasonably expect some portion to be temperature induced. However, linear extrapolation of the decline from MWP into the LIA, for example, tells us nothing about thermally induced components operating over longer, unknown lag times or their origin. You've done that again in your reply to Capell above.
Much more interesting to me is the degree of fluctuation in rate of CO2 growth around those volcanic events, the accompanying 'permanent' steps in lower stratosphere cooling and timing of subsequent major El Ninos. A more involved macro equilibration might be going on over longer timescales than generally thought following major volcanic events.
Michael Hart remarks above, the truth will likely be somewhere in between. But it might be elsewhere entirely. Amid this massive pile of guestimates and uncertainty (not least the ice-core record itself), the vital question is perhaps slightly clearer than it was but not by much.
Your contribution is immense and I thank you for your ever patient input. Please comment on Salby's emission to ppmv acceleration conversion (i.e. 0.275 GtC/yr^2 = 0.14 ppmv/yr^2). Strip away that differential; has he used acceleration derived from the first (very noisy) period to estimate the second? In your opinion, what is it derived from first principles?
Engelbeen
Thanks for your last reply. Yes, that does make sense. It brings both clarity and simplicity to the description of the CO2 sink mechanisms.
What is significant about Salby's paper, and those involved in the discussion across at WUWT (in which your contribution has been very significant) is that we've now departed from the IPCC's residence time of 200 years downwards to times which make observation of anthropgenic contribution saturation a possibility.
Anonymous,
If you repeatedly listen to the part where he introduces the "thermally-induced CO2 emissions", that is indeed the blue curve, but the blue curve hardly differs from the measured curve and still includes the full offset. What he describes by "subtracting the blue curve" point by point is in fact back integrating the total CO2 rate of change: "thermal" + human (or you can't match the total increase since 1980!)...
The problem to separate the increase between human and natural emissions is exactly in the offset.
If you look at human emissions and the increase in the atmosphere (all yearly averages to be comparable with the emissions):
http://www.ferdinand-engelbeen.be/klimaat/klim_img/dco2_em2.jpg
Human emissions increased from ~1 ppmv/year to ~4 ppmv/year over the past 55 years.
The increase in the atmosphere increased from ~0.5 ppmv/year to ~2 ppmv/year in the same period.
Both (and the sink rate) increased a fourfold in the past 55 years.
There are two important points here:
- Practically all increase is from human emissions, as the natural contribution is a net, increasing sink over time.
- The slope of the increase is caused by the slightly quadratic increase of total human emissions over the past 55 years, which gives a slightly quadratic increase in the atmosphere and thus a similar curve in sink rate. Taking the derivative gives three straight lines with a slope of the increase in the atmosphere about half the slope of human emissions.
If one may assume that both offset and slope of the derivative are caused by human emissions, the resulting effect of the variability is near zero (a very small offset) as it is only variability around the trend...
Thus depending how much of the offset and trend is attributed to temperature or humans, the increase is near fully from temperature increases or near fully from human emissions...
Further the bias introduced by cherry picking two smaller periods by Dr. Salby:
If you look at the full curve, the period 1976-1996 shows a negative slope in CO2 rate of change (even excluding the Pinatubo years), with maximal increasing temperature and increasing CO2 emissions. Seems rather odd if temperature is the driving force of the increase...
About using temperature or the derivative of temperature variations:
If the temperature of the earth increases with 1°C, vegetation in general will sink somewhat more CO2. The oceans will release somewhat more CO2 at the upwelling places and sink less at the sink places.
The equilibrium between ocean water and the atmosphere above it changes with 4-17 ppmv/°C, no matter if that is relative static (for the surface) or dynamic (with the deep oceans). The average in/decrease over many millennia was ~8 ppmv/°C.
If the temperature changes with a jump, the CO2 levels integrate to the new equilibrium over some time:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/upwelling_temp.jpg
If the temperature goes up and down with a sinusoid, the CO2 levels will follow with a sinusoid which lags 90° in time. That is what one can see in the combined graph of temperature and CO2 increase in the atmosphere, assuming 8 ppmv/ influence of temperature on CO2 levels.
If one takes the derivatives, both dT/dt and dCO2/dt shift back 90°, thus T changes and dCO2/dt changes synchronize, but that has no physical meaning. Integrating dT/dt gives the temperature influence on dCO2/dt which explains all the noise, but has near zero influence on the slope:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_dco2_d13C_mlo.jpg
The reverse dCO2/dt and dδ13C/dt changes prove that it is the influence of temperature on (tropical) vegetation which causes the variability. But vegetation is not the cause of the overall increase: it is a net, increasing sink for CO2 over time...
The slope of temperature since 1960 is good for a few ppmv of the total increase, while humans emitted twice the increase in the atmosphere. But even the 8 ppmv/°C looks overblown if you look at the influence of the variability around the trend...
Of course, the influence of temperature on variability and trend is the result of two different processes, where the variability has a sensitivity of 4-5 ppmv/°C, while the slope has a sensitivity of over 100 ppmv/°C if it was temperature induced, but it would be difficult to find such a natural process, which never occurred in the past 800,000 years, while human emissions more that fulfill that role...
Anyway, looking at the second (!) derivative in a very noisy year-by-year and even decadal noisy rate of change doesn't help much to give a clue in attribution of the increase to humans or natural causes. The main point again is that the variability of the rate of change in the atmosphere is fully at the sink side, not the source side and that other -longer- periods in time show increases in sink rate despite increasing human emissions. That is the result of natural variability...
Apr 14, 2015 at 12:17 PM | ...and Then There's Physics
Very stupid and naive pseudo-mass balance argument debunked here. Gavin Cawley is a computer scientist, not one of the hard sciences.
Apr 18, 2015 at 6:36 PM | Ferdinand Engelbeen
Stale assertions and poor reasoning.
"If the temperature goes up and down with a sinusoid, the CO2 levels will follow with a sinusoid which lags 90° in time."
Which means that CO2 is evolving according to the integral of temperature. That is the physical meaning. There is no way around it.
That means that the trend in temperatures is causing the trend in the rate of change of CO2. Emissions also have a trend, There is little to no room for them.
This is really elementary stuff, to one who genuinely understands the mathematical imperatives. It amazes me that there is even discussion about it. The data are very clear. No doubt about it. Humans have contributed an insignificant portion of the rise in atmospheric CO2.
Bart,
Small error in your reasoning:
A change in temperature integrates into a small, finite (8 ppmv/°C) change in CO2 level, with a 90° lag for a sinusoid.
By taking the derivatives, you shift both sinusoids 90° back in time.
That makes that dT/dt integrates into dCO2/dt,as there is again a 90° lag between the two.
As dT/dt has zero slope (even slightly negative with a small offset), it has zero influence on the slope of dCO2/dt and only a small part on the offset of dCO2/dt.
The backshift of the derivatives also makes that there is zero lag between T changes and dCO2/dt changes and thus that the trend in temperature does not integrate into the trend in the rate of change of CO2.
The integral of the temperature change over the past 55 years gives an amplitude of +/- 1 ppmv CO2 for the variability around the trend and a trend of about 5 ppmv.
Further your "debunking" of the mass balance fails completely on following point:
<I>S is a dynamic response. It is a feedback response to A, and is thereby a function of N and H</I>
where S is the sink capacity
A atmospheric increase rate
H human input
N natural input
S doesn't depend of the atmospheric increase rate, it depends of the integrated increase over time above the temperature dependent equilibrium, whatever the cause of the increase.
With the 110 ppmv atmospheric pressure above the equilibrium for the current average seawater temperature, the average sink rate is ~2.15 ppmv/year which gives an e-fold decay rate of slightly over 50 years.
If humans should stop all emissions today, the sink rate in the first year still would remain around 2.15 ppmv, decreasing over time until reaching the equilibrium again.
Thus currently nature, <I>on its own</I>, is a net sink, not a source.
Apr 18, 2015 at 9:29 PM | Ferdinand Engelbeen
This is gibberish, Ferdinand. Absolute gibberish. dT/dt does not integrate into dCO2/dt. T integrates into dCO2/dt. That is the meaning of the mathematical relationship
dCO2/dt = k*(T - T0)
No ifs, ands, or buts about it. And, since this relationship holds across the entire spectrum with no phase distortion, the trend in T aboslutely determines the trend in dCO2/dt. There is absolutely no way around it.
It is incredibly basic. You are arguing that 2 + 2 is not 4. You are wrong on a very elementary level.
"S doesn't depend of the atmospheric increase rate..."
Again, gibberish. S depends on the concentration, which is the integral of A. No matter how you slice it, S depends on A, and only by removing the influence of A entirely can you pronounce nature a net sink.
You almost get it when you say "decreasing over time until reaching the equilibrium again." Yes! In other words, S decreases. When you have reached equlibrium again, then the influence of A is gone. Only then, if you still had N - S less than zero, could you declare nature a net sink. But, S would then be smaller, so you wouldn't.
N - S would not still be less than zero. It would be positive, Because the integral relationship with temperature shows conclusively that human emissions have an insignificant effect on atmospheric CO2 level.
Only by completely eliminating the influence of H can you declare nature a net sink - I lost track of what the variables of interest were. Everything I wrote above holds mutatis mutandis. Only after the sinks have decreased back to the natural equilibrium could one declare nature a net sink.
That "mass-balance" argument is incredibly stupid, and put forward by people who are not familiar with the evolution of dynamic systems.
Bart,
You repeatedly said that a 90 deg. shift means integration. There is no 90 deg. shift between T and dCO2/dt, but there is between T and CO2 and between dT/dt and dCO2/dt:
dT/dt leads dCO2/dt with pretty the same variability, but has near zero offset and trend, thus isn't the main cause of the increase in the atmosphere, is that a problem?
Your formula
dCO2/dt = k*(T - T0)
doesn't hold: it literally says that there is no reduction in the CO2 increase rate for a small sustained shift in temperature, whatever the total CO2 increase above equilibrium is. No feedback at all from the CO2 increase in the atmosphere on the influxes and outfluxes from/to the oceans...
S depends on the concentration, which is the integral of A. which is what I said, not you. Better reread your old "proof" of debunking the mass balance argument. You wrote that the sink rate depends on the increase rate. The integral is far beyond the momentary human input and still gives a sink even if all human input would stop. Thus nature is a net sink now and for many years, even without any further human input and the mass balance argument holds anyway, whatever reasoning you try out to avoid it, our emissions don't land on the moon...
Whatever you may be sure of, I want to know if you agree with Henry's Law that a limited temperature jump of the oceans surface gives a limited CO2 increase, integrating towards a new equilibrium, as the oceans surface is a rather static part of the carbon cycle and has a rather fast exchange with the atmosphere...
Bart,
BTW, as you are so convinced that all increase is from temperature, there is no influence of "H", humans, on the total increase in the atmosphere, at least not in the 80 ppmv increase after 1960, thus also no influence on the increasing sinks.
Take human emissions away which are about twice the current net sink rate and according to you, the increase in the atmosphere still would go on unabated?
There are three things that are certain,
1) plant growth is greater in the summer than the winter,
2) the fizzy coke effect (aka Henry's law) is larger in the summer than then winter and
3) the atmospheric CO2 mixing ratio is LOWER in the summer than in the winter.
No bunny will dispute 1) and that means that photosynthesis will be higher in the summer, decreasing the amoung ot CO2 in the atmosphere 20 is the basis of Salby's claims and 3) can clearly be seen in the MLO record and from other stations. that monitor atmospheric CO2
IF Salby is correct, the level of atmospheric CO2 should be HIGHER in the summer when the oceans are warmer than in the winter.
Now some, not Eli to be sure, would be interested in the gymnastics to follow.
Simple. The elephant is enlarging, outgassing, and net sinking. We need more biologists touching the elephant.
Yeah, sure, I'm as blind as everyone else.
===========
Well yes, but the elephant would not be enlarging if Kim and the rest of us stopped feeding her peanuts. If Salby were right
a) CO2 would be higher in the Southern Hemisphere than the Northern because the Southern Hemisphere has more ocean, and warmer oceans than the Northern
b) Globally and regionally there would be more CO2 in the summer than the winter.
Both a and b are false, and in addition there is what Ferdinand has been pointing out. Salby is wrong and fortunately not everybunny is so dug in with Salby's crazy as Kim. Well, perhaps.
Hee, hee, the Bern Model is not adequate; you figure out why.
=========
Kim, the Bern model is probably overblown, as that includes a rapid saturation of the largest sink: the deep oceans, for which is not the slightest indication - yet. To the contrary, the current sink rate is somewhat higher than in other periods, so the sinks are doing well. But that doesn't mean much as in the period 1976-1996, sinks were working even harder...
That is just natural variability in sink capacity, which depends of temperature (El Niño), drought, light (Pinatubo),... and the increasing amount of CO2 in the atmosphere above equilibrium.
Anyway, nature as a whole is a net sink for CO2 every year of the past 55 years. One need a lot of c(r)ooked reasoning to turn a net sink into the main source of the CO2 increase in the atmosphere...
Thank you, Ferdinand. I've been reading your stuff for a decade and you are the main reason I believe that the rise is primarily anthropogenic. However, given our poor knowledge of biological sinks, and of dissolved CO2 in the ocean, isn't there a way for nature to be a net sink and for the warming to be a cause of the rise? I'm posing a hypothetical, and conjecturing that it might be so.
==================
Apr 19, 2015 at 8:26 PM | Ferdinand Engelbeen
"...it literally says that there is no reduction in the CO2 increase rate for a small sustained shift in temperature, whatever the total CO2 increase above equilibrium is..."
No, it says there is no significant reduction within the timeframe of observation. Within that timeframe, we can see what is happening, and it is very clear. That is all we need to deduce that human inputs have not been a significant influence within that timeframe.
"Thus nature is a net sink now and for many years..."
But, not once human influence is removed entirely. I do not know why you have so much trouble with this concept. The mass balance argument is stupid. Really, really dumb.
"I want to know if you agree with Henry's Law that a limited temperature jump of the oceans surface gives a limited CO2 increase, integrating towards a new equilibrium, as the oceans surface is a rather static part of the carbon cycle and has a rather fast exchange with the atmosphere..."
It isn't static. Every second of every day, new CO2 is coming in from the depths. A like amount has to be channeled back into the depths, or it will accumulate in the surface system.
You are, in effect, arguing the Skydragon's claim about the Greenhouse Effect. They say a colder object cannot heat a warmer one, and thereby conclude the GHE is phony. The mistake they make is that every second of every moment of daylight, new parcels of energy are coming in from the Sun, and they have to be dissipated, or the heat will build up. They are wrong, and you are making their mistake of treating this as a static system.
I have not yet concluded whether the change in atmospheric CO2 is driven by temperature alone choking off the downflux of CO2, or if a CO2 enriched bubble of upwelling waters has aided the process. What I do know for certain is that atmospheric CO2 is a temperature dependent process. Human inputs are not temperature dependent. Ergo, they are not the driving factor.
"...there is no influence of "H", humans, on the total increase in the atmosphere, at least not in the 80 ppmv increase after 1960, thus also no influence on the increasing sinks."
That is really twisted. No. The sinks are the reason human inputs have little effect. The CO2 has to go somewhere. That is where it is going.
Apr 20, 2015 at 4:30 AM | Eli Rabett
Winter and summer where? Not all the world is the Northern Hemisphere.
Apr 20, 2015 at 4:30 AM | Eli Rabett
"a) CO2 would be higher in the Southern Hemisphere than the Northern because the Southern Hemisphere has more ocean, and warmer oceans than the Northern"
It is higher in the Southern Hemisphere than the Northern.
"b) Globally and regionally there would be more CO2 in the summer than the winter."
There is more CO2 in the Northern Hemisphere summer than in the winter.