Tuesday
Aug062013
by 
Bishop Hill
Bishop Hill A new look at the carbon dioxide budget - Part 3
Aug 6, 2013 Climate: carbon budget In Part 1 of his paper, David Coe set out the failures of the IPCC model of carbon dioxide control to predict key observables in the ocean-atmosphere system. In Part 2 he outlined a new ocean control model that might better explain the observations. In Part 3 of his paper he looks at how this new model performs in practice.
The paper is attached below. Once again, the data for the figures is available too.
Reader Comments (29)
My brain hurts ;(
And mine.
But I still reckon it is a useful addition to the corpus of knowledge. No doubt the usual suspects will be along to debunk it. I would be happier if someone other than the usual suspects tried to pick holes in it in the interests of genuine scientific advance.
The obsession with "it must be CO2 because we
can't think of anything elsewant it to be" deserves more serious examination.Very impressive. But what are the implications for future CO2 concentrations given (different) projected emission trajectories?
Many thanks.
I see a new paper out, reported on Climate Depot, claiming the CO2 sensitivity as ''close to 0''. So we are getting closer to the truth.
What falsifiable predictions could be made based on this model?
Bloke, here's one:
That's from page 8. I was about to ask how easy it is likely to be to measure the isotope ratio (of C13 to C12 variants of CO2) in the deep ocean.
From page 14:
Disaster seekers, dig here? Let's not forget that it's right that science should look out for such things. But it must be decent science. It would be ironic but not unexpected if the faking of one looming disaster for political reasons led to another real problem being almost completely bypassed.
Thanks for all this David. I take it that although Gregg's oceanic photosynthesis figures help you to explain O2 levels you don't have any handle on the reasons for the decrease he reports? And that with only one paper to go on the uncertainty in this area has to be marked?
PBL
"But what are the implications for future CO2 concentrations given (different) projected emission trajectories?"
The implications for the prediction of future CO2 levels are significant suggesting a current overestimation of global heating by at least a factor of two and possibly much more. I am afraid you will have to wait until Part 4 for the detail.
Richard Drake
"I take it that although Gregg's oceanic photosynthesis figures help you to explain O2 levels you don't have any handle on the reasons for the decrease he reports? And that with only one paper to go on the uncertainty in this area has to be marked?"
I am afraid I don't, Richard. The only data I have been able to source is that by Gregg. I have also not been able to identify measurements of O2/N2 ratio since 2000, although that may be down to my lack of available time and resource (the day job keeps getting in the way). If anyone knows of such data please let me know. It could be most enlightening.
I'm sorry if I sound pernickety, but I take issue with your use of the term "control system". The equations do not seem to me to describe control, as it is widely understood. Rather they are 1st order mixing elements. Any true control system, i.e.: with feedback is determined by a 2nd oder DE. I would have to say that "control theory" is somewhat abused in climate science. See
http://judithcurry.com/2011/10/10/climate-control-theory-feedback-does-it-make-sense/
@ John Marshall
for climate sensitivity to actually physically exist changes in CO2 must be the dominant cause of changes in global temperature
if this is not true it's meaningless
climate scientists seems to have forgotten that My Ohm didnt just define his law
he actually experimented and observed for a given resistance twice the voltage was required for twice the current to flow in a circuit
in climate science they've done away with these boring time consuming details
“A persistent reduction in oceanic phytoplankton could have far reaching consequences. What are the reasons for this reduction..”
Bit of a bugger if it’s too many whales - what would Greenpeace do then..?
RC Saumarez
The sudden imposition of say a large slug of CO2 into the atmosphere will produce a positive bias to the partial pressure differential between atmosphere and ocean. This will result in a flow of CO2 from atmosphere to ocean until the equilibrium is re-established. This is a form of controlling action.
The seasonal 'global' SST temperature cycle drives the annual change in atmospheric CO2, due to different exchange coefficients between the warming and the cooling phase of a seasonal SST cycle.
This is a rather nice study on the 14/13/12C levels of DOC and DIC in marine sediments.
http://rtc.sfsu.edu/komada_lab/documents/GCA_2013.pdf
The only criticism one can make is that it would have been nice if they could have got further from the coast as terrestrial inputs make the data a combination of terrestrial/aquatic inputs.
This is a rather nice study on the 14/13/12C levels of DOC and DIC in marine sediments.
http://rtc.sfsu.edu/komada_lab/documents/GCA_2013.pdf
The only criticism one can make is that it would have been nice if they could have got further from the coast as terrestrial inputs make the data a combination of terrestrial/aquatic inputs.
@David Coe
That is damping - it is not control
Together, these papers mark a very important contribution that deserves much closer scrutiny. A niggle and a possible 'validation'.
The niggle is part three seasonal variation. Mauna Loa CO2 peaks in NH spring and troughs in NH fall. This is very powerful evidence that land based photosynthesis is mainly responsible, since much more land is NH. Does not invalidate the model, but makes the land/ atmosphere box predominant for seasonality.
Possible 'validation'. It is well known that much marine biosynthesis is trace iron dependent (leading to the ocean fertilizer bioengineering idea). It has recently been shown that in a number of phytoplankton species iron uptake is very pH sensitive, lower pH meaning lower uptake hence less photosynthetic activity. A possibly verifiable 'predicted relationship would be the measured average decline in pH to Coe's inferred decline in biome activity. A difficulty lies in the large diurnal and annual swings in ocean pH at given sites and across sites, perhaps requiring more data to statistically wash than presently exists. A second difficulty is that the strength of the effect is species dependent, so knowledge of mixed layer change in relative ocean populations of phytoplankton is necessary for sound calculation. Based on Coe's analysis,these would seem meritorous oceanography research projects.
Page 8.Concerning the postulate that the diffusion coefficient is inversely proportional to molecular mass:data for chemically similar solutes shows only a negative 0.43 dependence.This changes the ratio 1.023 to 1.01,which is much lower than the 1.063 required to validate the model.
Aug 6, 2013 at 4:06 PM | RC Saumarez
"That is damping - it is not control"
Whatever you want to call it, David Coe's definition is consistent with the argot in the field of control systems.
David - Will get back to you when I have had a chance to look over carefully.
@Bart,
It most certainly isn't. Where is the feedback?
I have no intention of having an argument with you on this thread but this is not control in the accepted sense.
Somehow I feel the decrease in phytoplankton is linked to overfishing, but just how is beyond me.
Behold the Noble Null, H0, natural oceanic variation, which must be thoroughly and unambiguously falsified with hard data, observations, before the Anthropogenic H1 gets a look-in. Fat flaming chance of that!
David, an edit note: the 1st para on p.20 has some duplicated lines.
Correction, p. 18 has the duplicated lines.
quote
Somehow I feel the decrease in phytoplankton is linked to overfishing, but just how is beyond me.
unquote
Scenario 1: oil and surfactant pollution reduce wave action, reduce wind entrainment and thus currents with their associated nutrient-rich upwelling, reduce bubble production, lessen the rate of mechanical CO2 pulldown. Fewer phytos because less nutrient in a stratified ocen, less pull down of CO2. Starving phytos yield to C4 metabolism types or, if they can, switch to C4 which discriminates less against heavier C isotopes and leaves a light isotope 'signal' in the atmosphere.
Scenario 2: Land use increases, increasing dissolved silica run-off. This advantages the diatoms which pull down less CO2, pull down relatively more heavy isotopes. CO2 in atmosphere goes up, with a light isotope 'signal'.
JF
There is a danger in perhaps reading too much into the observation of reduced phytoplankton activity. The evidence for this comes from just one paper (Gregg) and from a ten year (1990 to 2000) period of O2/N2 ratio measurements. Have we given up measuring this parameter, or have more recent results not been published? Has the reducing trend reversed? Did the data not fit the IPCC narrative. I simply do not know. What I desperately need is further data on atmospheric O2/N2 analysis.
RC: clearly you should stick to debating topics that you have prior knowledge of. I would recommend you phrase future responses regarding control theory in the form of questions, rather than accusations, lest you continue to demonstrate not only a lack of knowledge regarding the subject, but an unwillingness to learn the same.
Mark
As I am late in this discussion and only have read part 3 and not yet part 1 & 2, only some reactions on that part for now:
- seasonal variations are a result of oceanic and (land) vegetation reactions on temperature, mainly from the mid-latitudes. The growth and decay of vegetation is the dominant factor, as the drop in CO2 is accompanied with a peak in 13C/12C ratio. CO2 fluxes from oceans and vegetation are opposite of each other. The change in the SH is less pronounced and partly caused by the influx of NH air for near-equator stations. Global average ~5 ppmv/K
- the interannual variations are from both the oceans and vegetation. In this case working in parallel, as tropical vegetation temporarely (1-3 years) releases CO2 for higher temperatures (and drought). Global average ~4-5 ppmv/yr in the first year.
- the multidecade to multimillenia variations show a quite linear ratio of ~8 ppmv/K over 800 kyrs, where oceans and vegetation (area) proceed again in countercurrent, but then the oceans are dominant.
About the isotope ratio's: The deep oceans are at 0 to +1 per mil d13C, the ocean surfaces at 1-5 per mil, the latter depending of the biological uptake and decay, part of which is dropping out into the deep.
The isotopic fractionation sea-air is -10 per mil, the reverse is -2 per mil, in average (for fluxes in balance) thus -8 per mil.
The global balance in the atmosphere over the Holocene in the atmosphere is -6.4 +/- 0.2 per mil d13C, since ~1850 dropping to -8 per mil in full ratio with human emissions. A similar drop can be found in coralline sponges for surface waters:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
The drop in the sponges follows the drop in the atmosphere with 1-3 years.
That the d13C drop is less than expected is a matter of exchanges with the deep oceans: what goes in returns over ~1000 years. Therefore the human "fingerprint" is diluted with old 13C rich waters. That can be used to estimate the deep ocean - atmosphere exchanges:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/deep_ocean_air_zero.jpg
The same happened with the 14CO2 bomb spike: the decay rate of 14CO2 in the atmosphere is over 3 times faster than of an excess amount of 12CO2, because what returns from the deep oceans is less than halve the amounts of the 14CO2 bomb spike which goes into the deep.
About the oxygen measurements:
These are extended by Bender e.a. to 2002:
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf
Fig. 3.9 is completely at odds with the observations, which show an average pCO2 from the atmosphere some 7 microatm above the pCO2 of the oceans. See Feely e.a.:
http://www.pmel.noaa.gov/pubs/outstand/feel2331/exchange.shtml