Bishop Hill A new look at the carbon dioxide budget
Jul 30, 2013 Climate: carbon budget As readers are probably aware, I don't spend a lot of time on new hypotheses about global warming. Apart from intermittent looks at Svensmark's cosmoclimatology work, I've tended to concentrate on mainstream science and its relationship with policy, as well as a lot of "meta" stuff like peer review.
However, I was recently sent a paper by reader David Coe that piqued my interest. It seemed to me to be put together pretty well, and was about an area of the science that I knew nothing about. Being somewhat wary about this kind of thing though, I've sought expert opinion, and this suggests that at least some of what is said is good and new and interesting. So I am going to post the paper up, with the caveat that it is only a discussion paper and parts of it may be wrong. Readers are cordially invited to throw stones at it.
The paper is written in four parts, which I will post at a rate of one every 3-4 days.
Here is the first part, which sets out the problem.
Reader Comments (122)
Now that the discussion has arrived at a fascinating impasse about the 2nd law law of thermodynamics, Boltzmann and the structure of the CO2 molecule, could everyone please tell us your estimate for climate sensitivity to 2 decimal places.
I was going for 2.67 until I remembered Jasper Kirkby . Now I am back to 0.02.
Paul Matthews
"Convection is a much more effective method of heat transfer than conduction. Cold water from the polar regions sinks. That cold water doesn't come from melting ice caps, it's just cold polar water.
It's like having an air conditioner at one end of a room, in a flat where the flat below you has the heating turned on!"
That is just the point. It takes energy to remove energy when that removal is against all the temperature gradients. Where is the energy source to drive the "air con" that is the poles? Cold polar water has to be chilled by something especially if that cold water is to become the refrigerator of the deep ocean. We are talking about huge amounts of energy.
Michael Larkin
The linear relationship exists between the increase in observed atmospheric CO2 levels in ppm and the rate of CO2 emissions in ppm/yr. The implication is that if the emissions could be stabilised at current levels, not reduced, then the atmospheric CO2 levels would stop increasing. This of course has a huge impact on all government policies involving climate change.
@David Coe
A useful and informative start. I particularly welcome your drawing attention to the seasonal CO2 variation (1.3), for the following reason:
You write: "During the summer months, when plant growth is active, CO2 absorption by photosynthesis is high and atmospheric CO2 levels fall." I can find its like in many sources, but they all rest on an unsound assumption.
Seasonal CO2 level will *not* fall if CO2 is in excess - as arguably is the case in the oceans.
The observed fall is most simply explained as the aggregate response to a limiting nutrient. I've as yet found no plausible alternative argument.
As part of the IPCC's brief is the "environmental...impacts" of "climate change" from "continued growth...of greenhouse gases", the absence of substantive discussion of this inference is notable.
I think your open question on the persistent source of the CO2 needs also to address its sink.
"Cold polar water has to be chilled by something"
Nope - you've got thermodynamics inverted here.
Things need energy to remain warm. Lack of energy at the poles results in things getting colder. Ocean current provide inputs of warmer water. Lack of energy prevent the water from getting colder. The colder water sinks and flows away from the poles at close to freezing.
No energy source is required to do the cooling - this isn't a fridge!
David Coe, is this the correct you?
I read physics at Wadham College Oxford.
I am Managing Director of CODEL International, a company based in Bakewell, which manufactures equipment for monitoring atmospheric pollution.
Oops - "Lack of energy ensures that the water gets colder." not what I said before.
David Coe,
OK. So you seem to be saying that if the rate of emissions is currently X ppm/yr, then if we keep it at X, atmospheric concentration will stay at at its current value of ~400ppm.
If that's the case, then every year, X ppm would seem to have to disappear from the atmosphere into sinks. And if we increased it to X+Y ppm/yr, but then stabilised emissions at that higher value, would X+Y ppm disappear into sinks?
Sorry if my questions are naive, but I want to be sure.
AlecM
"The oceans are cold because they are the obverse of the Hadley cells which take heat from the tropics, transfer it to Space then precipitate the moisture near the poles. Rain is cold and the water which falls as snow at the poles loses even more heat to Space.
SW does penetrate the oceans but there is almost perfect equilibrium with the air as a heat sink, and that takes place at night as well. The key equilibrium is the heat which diffuses into the oceans coupled to ions acting as coupled thermal and mass diffusion, with the endothermic enthalpy of mixing."
I suspect that we might have to agree to disagree on this one. To be convinced I would need to see some energy balance calculations. Climate scientists, with a few notable exceptions, Murry Salby being one, are either reluctant or incapable of constructing mathematically based arguments with actual numbers to support those arguments. Climate science typically resorts to hand waving.
Derrick Byford
That's me!
Michael Larkin
Yes, in a nutshell. The question is what are the sinks? To resolve this dilemma we need to rethink the principles of CO2 sources and sinks. Part 2 of the paper is dedicated to that task.
Various functions might be fitted to the measured increase in the yearly averaged atmospheric CO2 with time. This is just ordinary curve-fitting, unless there is a specific reason to prefer one functional form over another. If an exponential is chosen, for example, the linear relationship pointed out by David Coe follows immediately.
Let C = p exp(qt) + r, where p, q and r are constants.
Then dC/dt = q(C-r).
I do have a tendency to make silly mistakes with simple algebra but if for once I have not, there doesn't seem to be anything very profound about Figure 1.5 other than a simple way to estimate q and r.
On the other hand I may have missed the point completely of course!
steveta_uk
If cold water sinks at the poles, then somewhere on the planet warm water must be rising to the surface. However the deep ocean is uniformly cold. At what location does it become warm so that it rises to the surface? Bear in mind that in the tropics where sea surface temperatures are in excess of 25 degC the deep ocean temperatures must exceed those temperatures to upwell.
All the temperature gradients will tend to warm the deep ocean. To chill it requires energy. A refrigerator is exactly what is required.
Mark Well
You have it exactly right. The question is what do the constants q and r represent? Without association with real world parameters the issue becomes, as you suggest, a curve fitting exercise and is thus meaningless. Ask yourself what the physical interpretation of the differential equation dC/dt = q(C-r) might represent.
David Coe,
Thank you very much for your patience--you're a scholar and a gentleman. I really am looking forward to further instalments. All sorts of questions are buzzing round in my mind right now, but perhaps I'd better wait for the next one, since you might answer them there.
Michael Larkin
Thank you. I look forward to further discussion.
Michael Larkin and David Coe,
If you haven't already read Hansen's parting gift to sceptics when he retired fro NASA, you might find it interesting.
http://iopscience.iop.org/1748-9326/8/1/011006/pdf/1748-9326_8_1_011006.pdf
Especially figure 3 and page 3, where he indicates that the carbon sinks and atmospheric fraction due to supposed anthropogenic CO2 are headed in the "wrong" way from what the IPCC/consensus says they should be.
I'm still picking my jaw up from the floor as a result of seeing such a frank admission, which makes me wonder if Hansen really wrote it and knew what he was putting his name to. It is also a little light on how exactly this was arrived it, but I'm sure those poorly understood carbon-isotope fractionations will be in the thick of it.
In fact I am still digesting it because I must still hold myself to be very cautious about what I read in this field, especially if it appears to confirm what I had long suspected, i.e. that they really don't have much clue what is going on. I'm sure carbon-cycle models are no less susceptible to "tuning" than all the other models and their frenzied couplings.
David Coe, see here:
http://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Thermohaline_Circulation_2.png/800px-Thermohaline_Circulation_2.png
David Coe reply the Steveta_uk.
We have a refrigerator. It's the strongly endothermic enthalpy of mixing of saline surface water and near fresh melt water from the poles. The whole point of this is that the decrease of entropy as the cations cause water to order, Na+ increases the relaxation time from 10^-12 to 10^-8 s, means Gibbs free energy increases dramatically whilst temperature remains constant.
The working fluid of the fridge is air then water advection driven by SW energy and its conversion to much higher radiation entropy LW energy to Space. This is a slowly evolving part of Climate Science because few in the subject understand it. along with a very poor understanding of radiative physics..
David Coe
As a sceptic I mustn’t say this, but if the CO2 increase really is man-made, despite everything, then obviously it is simply governed by the requirements of human civilisation and the exponential really is only curve-fitting.
Regarding the ocean, I think it is correct to say that there could easily be a slow circulation even at constant temperature. The circulation would be driven by buoyancy and also by the rotation of the Earth together with friction at the sea bed. I would guess that rotation would in principle have exactly opposite effects in the Northern and Southern hemispheres if it were not for the skewed axis of rotation and the different sea bed geometry. I suspect that a couple of other recent comments (that I haven’t properly understood) might be referring to the buoyancy mechanism.
"I have sought expert opinion"
Please get back to us after you have found it.
Michael Hart,
"Especially figure 3 and page 3, where he indicates that the carbon sinks and atmospheric fraction due to supposed anthropogenic CO2 are headed in the "wrong" way from what the IPCC/consensus says they should be."
Yes, I quickly spotted fig 3, and now I'm confused, because I don't see a straightforward linear relationship between CO2 emissions and what he calls the "airborne fraction". What I see is CO2 emissions increasing whilst atmospheric concentrations, if anything, seem to be on a slight downward trend. Have I got that right, or am I missing something?
steveta
I am aware of the principles of thermohaline circulation outlined in the Wiki link that you provided. I simply dispute the story. If I am right then oceanographers have got it wrong for the past 60 years. I am not wishing to appear arrogant. If I am wrong then no doubt I will end up with egg all over face. I am simply trying to broaden the debate with what are, I believe, new ideas based upon simple observations and questions. Please keep shooting because these ideas need testing.
AlecM
I don't dispute the mechanism that you describe. I just don't believe it to be sufficient to achieve the observed effects.
"The 4 deg maximum density applies to pure water. Sea water has a maximum density at less than 0 degC. In any case the issue is about what happens to the 6.8 x 10^17 kj of energy inputted annually into the oceans by conduction through the seabed. Why does this not warm the ocean?"
It does, very slightly, the cold, salty, well oxygenated polar water that fills the deep ocean eventually (1000-2000 years) upwells ánd is replaced by new very slightly colder water. Note that the deep ocean for obvious reason always contains the heaviest water available. This style of thermohaline circulation is perhaps the most striking characteristic of the current "ice-house" climatic regime that began with the opening of the Southern Ocean about 35 million years ago.
Under the previous "hot-house" regime the heaviest water in the ocean was warm, very salty, oxygen poor, tropical water from the equatorial Tethys ocean. At that time the deep ocean were warm enough for comfortable bathing, but low in oxygen (occasionally even anoxic).
I am surprised that although Beck is mentioned, no-one has mentioned Jaworowski's critique of ice core measurements of CO2.
http://www.21stcenturysciencetech.com/Articles%202007/20_1-2_CO2_Scandal.pdf
There is a good explanation of ocean temperature here, by the late Dr Robert Stevenson, an oceanographer who spent 50 years at his trade:
http://www.21stcenturysciencetech.com/articles/ocean.html
If the sea were not water but a combination of water and mercury the mercury would settle to the deepest points. In just the same way cold brine is denser than warm brine and will settle to the deepest points. The levels will stratify. Cold brine is constantly being produced at the polar regions and sinking under warmer water that comes from tropics. It stands to reason that the deepest oceans will have the coldest fluid available. The sun only warms the top of the ocean even in the tropics. Water 5 miles down at the equator receives as much solar energy (i.e little) as water deep at the poles. Heat from Earth's crust is trivial in comparison to cold currents - you said 10,000 years per degree. Perhaps it is just enough heat keep temperature at 3 rather <0.
This is an interesting topic but what does this have to do with the price of spuds - or CO2 climate change for that matter? Is it related to Trenberth missing heat topic?
"At that time the deep ocean were warm enough for comfortable bathing"
Comfortable? At 9000 PSI?
Does your Figure 1.5 have an error of a factor of 10? It shows 1 ppm of emissions creating 5 ppm concentration.
Can you provide your data sources for us to check?
Roger A. Pielke Sr @RogerAPielkeSr (8minutes ago on Twitter)
Question - If heat were being sequestered deeper into the ocean than assumed by the IPCC, wouldn't CO2 also be sequestered at those depths?
He doesn't know. Same as Hansen is obviously uncertain about various issues in his paper.
I hope someone is keeping track of climate sensitivity through these exciting debates. I reckon it's between 0 and 100 . In fact I am sure of it.
David Coe
Offhand I can think of four ways in which geothermal heat entering the deep ocean can reach the surface and be radiated/ convected away.
1) The thermohaline circulation circulates water into and through the deep ocean. The main inputs are localised in the Greenland Sea and around Antarctica. The displaced water rises in a more diffuse manner , particularly in the Indian Ocean, North Pacific, and Carribean.
2) Cold currents such as the Humboldt current off Peru and Chile bring deep ocean water to the surface in response to local weather, and seabed contours.
3) In the Pacific ENSO brings cold, deep water to the surface during La Nina events.
4) A large proportion of the geothermal heat release is at volcanoes and hydrothermal vents. In both cases the temperature increase is enough to disrupt the normal temperature stratification below 700M and allow convection to carry heat upwards to mix into shallower layers.
First post to the Bish.
Why is the ocean so cold is a question I posted to RealClimate a while back. Dr. Schmidt's answer was "The answer is contained in the GCM's." Regarding the number for flux from the core, I would dispute this. I estimate it to be above 0.15, not 0.06.
Here is a quick and dirty estimate
0.84 kJ/kg.K Heat Capacity of Basalt
800 k temperature at bottom of crust
275 k temperature at bottom of ocean
525 k delta T
5000 m distance
1.7 W/(m.K) Thermal conductivity of basalt
0.1785 W/m² Rate of addition of heat to the ocean
David Coe
May I ask who this paper is aimed at?
If it is aimed at fellow sceptics it should go down well because it is telling them what they want to hear, in a style already familiar from spin-sceptic blogs such as Bishop Hill.
If it is intended to be read by non-sceptics , may I suggest a change of style.
Consider this paragraph.
"Papers in scientific journals and in IPCC assessment reports suggest that ocean currents
transfer warm waters to the polar regions, where they are chilled and descend into the
ocean depths to be slowly transported to the equatorial regions where they unwell as warm
water back to the surface again. If you like fairy stories this one is just for you!"
You simplified a considerable amount of theoretical and empirical oceanographic research into a straw man and dismissed it with one sarcastic comment. At that point I, a non-sceptic, classified the whole paper as spin-sceptic propoganda and stopped taking it seriously.
Yes I was , but I found there were some aspects I did not understand. As I looked at each one, it lead to others, which lead to others in turn.
Also, there are a lot of warmist arguments that if you inject a pulse of CO2, the individual molecules are quickly absorbed, but they are replaced by others, so the increased level of CO2 persists much longer. I think they are wrong, but any paper would need to explain how they are wrong and I have other things to keep me busy.
There is a paper by Gavin Cawley (an SkS blogger) Gavin C. Cawley, "On the Atmospheric Residence Time of Anthropogenically Sourced Carbon Dioxide", Energy & Fuels, volume 25, issue 11, pages 5503–5513, 2011.
http://pubs.acs.org/doi/abs/10.1021/ef200914u
http://www.skepticalscience.com/essenhigh_rebuttal.html
I think his reasoning is wrong, but I have not pursued it. I had a cordial discussion with Dr Cawley and he clarified some points for me, but I did not take it further.
I haven't read the paper yet but the exclamation marks and shoutiness means that for me the thing falls at the first hurdle.
It comes across like Alec M on valium. Sorry but there it is.
EM
You're letting your cynicism out again.
I thought the purpose of this paper, and of 'publishing' it here was fairly straightforward. Somebody has a new idea (not something that the warmists are comfortable with) and is asking for critical comments — which he has been getting.
The idea that everyone who reads/writes here instantly applauds everything that doesn't toe the Mann-Jones Line simply marks you out as a follower of the Truro Troll.
Likewise the idea that this is a perfectly formed piece of research is patently at odds with the facts as both Montford and Coe have said.
Let's see what the rest of it says before being over-critical of the style which, yes, would need a bit of tidying ahead of serious publication.
Why are the deep oceans so cold if 6.8x10^17 KJ flow through them annually?
I may be thick but
Volume of the hydrosphere = 1.33x10^9 Km^3
Assume that one third of this is in deep oceans:
=.44x10^8 Km^3
=.44 x10^17 m^3
=.44 x10^20 Litres
1KJ will raise the temperature of a liter of water 0.23 dec C
=> 6.8x10^17 KJ will raise the tempearture by 0.015 deg C.
Yes, CO2 levels have been rising as have C emissions, so there will be a correlation regardless of causation, just as there was with temperature between 1975 and 2000. Plotting the change in CO2 as a function of annual C emissions provides an indication of the uncertainty in the relation. There is in fact a significant slope of 0.2 ppm CO2 per 1000 million tons of C emissions, but the R^2 is not that impressive, at 43% (see Dropbox graph linked below, CO2 data from NASA Scripps, emissions data from Oak Ridge).
The simple plot doesn't take into consideration the lifetime of CO2 in the atmosphere, however. The C-14 curve from the bomb testing provides a clear residence time of about 14 years as I recall. Much discussion of that with Willis Eschenbach, Nick Stokes, Ferdinand Engelbeen and others at the WUWT blog. Martin A might be interested in that.
https://dl.dropboxusercontent.com/u/75831381/CO2%20%20change%20with%20C%20emissions.pptx
Mike Jackson:
But this is serious publication. I don't have any criticisms of the style either. Let's get used to the way science is now going to be done. One can tell from the responses of David Coe to critics from various directions that this is the real thing. Surely it's obvious by now that serious searches for truth are going to use more informal language - whether it's the precision irony of a McIntyre or the more acerbic (yet frequently hilarious) Eschenbach. And humour has always advanced understanding.
A worthwhile effort at so many levels. I'm learning and that remarkable condition looks set to continue. Think how much in just one day, compared the old ways.
And "shear fluke," though only wrong by one letter, seemed highly suggestive. Where's Dr Freud in his slip when we need him?
I seem to recall a transmission band in water down near 10 degrees C but I could be wrong. The uniformity with depth is a clue to something odd.
"And "shear fluke," though only wrong by one letter, seemed highly suggestive. Where's Dr Freud in his slip when we need him?"
A reference to the amazing dismissal of Radiosonde balloons?
The explanation is convective circulation. The water in the top layer of the tropics is warmed and rises, flowing across the surface towards the poles. This inevitably results in water from below being lifted up. Because the water is flowing upwards at a constant rate, and heat conducts downwards at a rate that slows with depth, there is a point where the flow rates balance. Below that point, temperature is dominated by its ultimate source at the poles. The answer to the question of where the geothermal heat goes is that it rises along with the rest of the water and is radiated to space at the surface. The circulation is fast enough - on the order of a few thousand years - that the resulting temperature rise is small.
I think this is the equivalent problem for climate science as was the photoelectric effect for quantum theory. So far there is no explanation from any GCM model that even come close to explaining as to why Earth's climate favors this value. Science must explain exactly what determines why such low levels of CO2 exist in the atmosphere.
One hint is that ~ 300ppm seems to optimize radiative cooling from the atmosphere.
see graph here
The peak for atmospheric OLR occurs for ~ 300ppm which just happens to be that found on Earth naturally. Can this really be just a coincidence ? It is almost as if convection and evaporation act to generate a lapse rate which maximizes radiation cooling by CO2 to space. If this conjecture is true in general, then any surface warming due to a doubling of CO2 levels would be offset somewhat by a change in the average environmental lapse rate to restore the radiation losses in the main CO2 band. In this case the surface temperature would hardly change.
More fundamental is the question – what causes CO2 concentrations to be ~300 ppm in the first place ? Maximum entropy increase is ensured by maximum radiation loss to space and for CO2 today that just happens to coincide with 300 ppm ! Could it really be possible that planetary thermodynamics drives the carbon cycle ?
Apologies for radio silence for the last few hours. Life keeps getting in the way. I make no apologies for the style of the paper. I have absolutely no intention of submitting this or any other paper for peer review, a process that I view as totally discredited. In which case I feel no constraint to conceal my contempt for for the quality of the science of countless papers that I have studied from the references in the IPCC assessment reports. I am more than content to argue my case with the readers of this blog, for whom I have much respect. Scientific truth is the one thing that can never be stifled. If my postulate, which will hopefully become clearer in part 2, is correct then I will be able to successfully argue my case. If not then some of you learned readers will assuredly put me right.
On the question of temperature of the deep ocean, several possible causes have been described in these comments. As is common throughout climate science and oceanography none of them offer quantifiable proof of their correctness. The whole process appears to be plagued with qualitative hand waving. This is the equivalent of design on the back of a fag packet. Please lets get down to detail. Only by doing so will we learn the truth.
"So far there is no explanation from any GCM model that even come close to explaining as to why Earth's climate favors this value. Science must explain exactly what determines why such low levels of CO2 exist in the atmosphere."
I understand science's answer is "the rise of the Himalayas".
In the long run, the total amount of carbon in the oceans depends on geology. Some is used up in erosion, some is released when carbonate rocks are subducted and released in volcanoes, some is deposited or dissolved on the sea bed, and yes, the formation and burning of fossil fuels. If you look at the geological record, you'll see it's not constant and it's not in any sort of equilibrium. But it's very, very slow.
In the short run, the primary determinant of CO2 is the ocean surface temperature, which determines the balance between atmosphere and ocean. You have a roughly fixed total amount of carbon in the oceans/atmosphere/biosphere, and it sloshes from one reservoir to another. CO2 is less soluble in warm water, so it is released from the oceans in the warm tropics, and dissolved again in the cold polar waters. If the temperature rises, more is released and less absorbed. The recent rise in temperature can explain about 10% of the rise in CO2.
It goes up and down because of temperature, but the average it varies around is set by the total amount of carbon in the system, which is an accident of history. The recent rise of the Himalayas has increased the amount used up in erosion, and caused the CO2 level to plummet.
Arguably, 280 ppm was getting dangerously low, and we have saved the world from slow-moving disaster on a timescale of tens of millions of years. Maybe the next dominant species to come along will be grateful.
Man's search for meaning takes a new turn. :)
Jul 30, 2013 at 6:22 PM | John Eggert
Here's a paper on the subject of heat flux from earth's core:
http://www.mantleplumes.org/WebDocuments/Hofmeister2005.pdf
The figure given in the paper is 63 mW/m² (see Table 2 on page 170).
Using that figure it is possible to calculate a trend in ocean heat content of 0.7 x 10²² J/decade which is close to the NODC Northern Hemisphere 0-2000m trend in ocean heat content but only about 10% of the Southern Hemisphere 0-2000m trend. Since 0-2000m is hardly the deep ocean, it is only of interest to note that the calculated figure for heat flux from the core is of a similar order of magnitude to other ocean heating effects.
bit O/T but dumb question again
but talking of geology - re - "the rise of the Himalayas" - Jul 30, 2013 at 10:38 PM | Nullius in Verba
"In the long run, the total amount of carbon in the oceans depends on geology. Some is used up in erosion, some is released when carbonate rocks are subducted and released in volcanoes, some is deposited or dissolved on the sea bed, and yes, the formation and burning of fossil fuels. If you look at the geological record, you'll see it's not constant and it's not in any sort of equilibrium. But it's very, very slow."
I have always wondered how long it will take for oil/coal seams etc to be subducted & lost forever to mankind (and womankind) in the earths hot layer below, only to be erupted at some distant epoch (same effect as burning them now Shirley) ?
lesson learnt would be to use it or lose it maybe ?
ps. thanks to David Coe & you Bish for putting his ideas out there & comments from all.
Jul 30, 2013 at 12:45 PM | David Coe
...
Now you're talking ... the SCAM has been treated too politely; BS is BS just like a spade is a spade.
As we say on the golf course, "You da Man !" LOL.