There is quite a bit of buzz surrounding a talk and pending paper from Prof. Murry Salby the Chair of Climate, of Macquarie University. Aussie Jo Nova has excellent commentary, as has Andrew Bolt in his blog. I’m sure others will weigh in soon.
In a nutshell, the issue is rather simple, yet powerful. Salby is arguing that atmospheric CO2 increase that we observe is a product of temperature increase, and not the other way around, meaning it is a product of natural variation. This goes back to the 800 year lead/lag issue related to the paleo temperature and CO2 graphs Al Gore presented in his movie an An Inconvenient Truth, Jo Nova writes:
Over the last two years he has been looking at C12 and C13 ratios and CO2 levels around the world, and has come to the conclusion that man-made emissions have only a small effect on global CO2 levels. It’s not just that man-made emissions don’t control the climate, they don’t even control global CO2 levels.
Salby is no climatic lightweight, which makes this all the more powerful. He has a strong list of publications here. The abstract for his talk is here and also reprinted below.
PROFESSOR MURRY SALBY
Chair of Climate, Macquarie University
Atmospheric Science, Climate Change and Carbon – Some Facts
Carbon dioxide is emitted by human activities as well as a host of natural processes. The satellite record, in concert with instrumental observations, is now long enough to have collected a population of climate perturbations, wherein the Earth-atmosphere system was disturbed from equilibrium. Introduced naturally, those perturbations reveal that net global emission of CO2 (combined from all sources, human and natural) is controlled by properties of the general circulation – properties internal to the climate system that regulate emission from natural sources. The strong dependence on internal properties indicates that emission of CO2 from natural sources, which accounts for 96 per cent of its overall emission, plays a major role in observed changes of CO2. Independent of human emission, this contribution to atmospheric carbon dioxide is only marginally predictable and not controllable.
Professor Murry Salby holds the Climate Chair at Macquarie University and has had a lengthy career as a world-recognised researcher and academic in the field of Atmospheric Physics. He has held positions at leading research institutions, including the US National Center for Atmospheric Research, Princeton University, and the University of Colorado, with invited professorships at universities in Europe and Asia. At Macquarie University, Professor Salby uses satellite data and supercomputing to explore issues surrounding changes of global climate and climate variability over Australia. Professor Salby is the author of Fundamentals of Atmospheric Physics, and Physics of the Atmosphere and Climate due out in 2011. Professor Salby’s latest research makes a timely and highly-relevant contribution to the current discourse on climate.
Salby’s talk was given in June at the International Union of Geodesy and Geophysic meeting in Melbourne Australia. He indicates that a journal paper is in press, with an expectation of publication a few months out. He also hints that some of the results will be in his book Physics of the Atmosphere and Climate which is supposed to be available Sept 30th.
The podcast for his talk“Global Emission of Carbon Dioxide: The Contribution from Natural Sources” is here (MP3 audio format). The podcast length is an hour, split between his formal presentation ~ 30 minutes, and Q&A for the remaining time.
Andrew Bolt says in his Herald Sun blog:
Salby’s argument is that the usual evidence given for the rise in CO2 being man-made is mistaken. It’s usually taken to be the fact that as carbon dioxide concentrations in the atmosphere increase, the 1 per cent of CO2 that’s the heavier carbon isotope ratio c13 declines in proportion. Plants, which produced our coal and oil, prefer the lighter c12 isotope. Hence, it must be our gasses that caused this relative decline.
But that conclusion holds true only if there are no other sources of c12 increases which are not human caused. Salby says there are – the huge increases in carbon dioxide concentrations caused by such things as spells of warming and El Ninos, which cause concentration levels to increase independently of human emissions. He suggests that its warmth which tends to produce more CO2, rather than vice versa – which, incidentally is the story of the past recoveries from ice ages.
Dr. Judith Curry has some strong words of support, and of caution:
I just finished listening to Murry Salby’s podcast on Climate Change and Carbon. Wow.
If Salby’s analysis holds up, this could revolutionize AGW science. Salby and I were both at the University of Colorado-Boulder in the 1990′s, but I don’t know him well personally. He is the author of a popular introductory graduate text Fundamentals of Atmospheric Physics. He is an excellent lecturer and teacher, which comes across in his podcast. He has the reputation of a thorough and careful researcher. While all this is frustratingly preliminary without publication, slides, etc., it is sufficiently important that we should start talking about these issues. I’ll close with this text from Bolt’s article:
He said he had an “involuntary gag reflex” whenever someone said the “science was settled”.
“Anyone who thinks the science of this complex thing is settled is in Fantasia.”
Dr Roy Spencer has suspected something similar, See Atmospheric CO2 Increases: Could the Ocean, Rather Than Mankind, Be the Reason? plus part 2 Spencer Part2: More CO2 Peculiarities – The C13/C12 Isotope Ratio both guest posts at WUWT in 2008. Both of these are well worth your time to re-read as a primer for what will surely be a (ahem) hotly contested issue.
I’m pretty sure Australian bloggers John Cook at Skeptical Science and Tim Lambert at Deltoid are having conniption fits right about now. And, I’m betting that soon, the usual smears of “denier” will be applied to Dr. Salby by those two clowns, followed by the other usual suspects.
Smears of denial and catcalls aside, if it holds up, it may be the Emily Litella moment for climate science and CO2 – “Never mind…”
incidentally, the author of that article, in ch5 estimates that 121GT of carbon are emitted underwater. That is an estimate of some 139,000 underwater volcanoes inferred from typically sized oceanic plate volcanoes.
However, its an estimate. Perhaps there isn’t a data source that says how much enters the atmosphere. I can’t imagine it all stays in the ocean. The oceans would be an acid bath, surely, if that were the case.
M. D. Smith,
I like your answers to John Finn, but he is not likely to accept them being a “true believer”. You can use this physical evidence to illustrate your sink and stopper analogy. The frigid water of the Arctic ocean is our greatest sink for CO2. Each year when it is dark and heat is radiating to space, the Arctic freezes over and stoppers the sink (and also slows the rate of heat loss). CO2 concentrations rise at a rapid rate as the stopper is being closed. Once closed, the rate of rise decreases to the long term rate that CAGW claims is from our burning fossil fuel but is more likely the rate of delivery from the equator. When the sun comes up and starts to melt the ice, CO2 concentrations decrease rapidly and reaches a minimum at the same time that the area of the ice stopper is a minimum. This observed behavior in the Artic will give you an inverse SST (skin surface temperature) – CO2 concentration correlation.
Fred H. Haynie,
I agree with the arguments in your presentation. What do you think of the similarity of the variations in global sea ice and CO2 rate of change (double peak)? Coincidence?
http://www.climate4you.com/images/NSIDC%20GlobalArcticAntarctic%20SeaIceArea.gif
http://www.woodfortrees.org/plot/esrl-co2/from:1995/derivative
Fred H. Haynie says:
August 7, 2011 at 11:38 am
Right. I used the maximum slope I could find the in seasonal data to find that the rate of exchange between oceans and atmosphere must be faster than 7.2 years (otherwise this slope could not be reached). I suspect it is actually much faster than that.
There is a process that explains the dCO2/dT relationship. Like I said, this fast rate precludes accumulation of too much anthropogenic CO2, the drain size at the source / sink is too big to allow it. I think the rate I’ve described can be used to determine the value of the resistor in the circuit, if you will. Haven’t got all the way there. There appears to be a very free flow between atmosphere and ocean, with just the net effect visible.
Anyone have any ideas on how to develop this?
P Wilson says:
August 7, 2011 at 10:50 am
“Thanks for the link Slioch, but i meant objective and authoritative data.”
That is what I provided you with.
What you were looking for was spurious data that supports what you want to believe.
Well I don’t know how many times I have mentioned here (at WUWT) that it is just 800 years since the Mediaeval Warm Period, when Temperatures were warmert than they are now.
Also related to this and other climate fictions, is the interminably related; including here at WUWT by presumably informed PhD Physicists, misinformation that the ordinary neutral atmospheric gases, such as N2, O2, Ar, even H2, DO NOT radiate an infra-red continuum thermal spectrum of Electro-Magnetic Radiation, due to simply the atmospheric Temperature. Atmospheric LWIR emissions can ONLY come from resonance emissions from polar GHG molecules, since neutral and homo diatomic molecules have no electric dipole moment, and therefore cannot radiate EM radiation in accordance with Maxwell’s equations for the electro-magnetic field.
Well it is time to call such theory what it is; hogwash !
Neutral gases can; indeed must, and do emit a continuum thermal spectrum due solely to the Temperature of the Atmosphere.
The origin of such radiation is no mystery. According to Maxwell, any varying electric current covering any non-zero distance, must result in the radiation of EM waves, that travel at the speed of light (c). Well a varying current (di/dt) is also an accelerating electric charge (d2Q/dt^2).
Neutral gas atoms, or homo-diatomic molecules such as N2 contain electric charges (electrons and protons). Such a (gas) molecule, or atom is in free ballistic flight subject only to the gravitation force, so the acceleration is very modest.
However eventually, the atom or molecule, will undergo collision with another, and at ordinary atmospheric Temperatures, the result is an elastic scattering; not unlike the rebound of a billiards cue ball. During the time that the molecules are in collision, so that their electrons and protons, can feel each other’s Electric fields, the charges are undergoing acceleration and according to Maxwell, they must (and do) radiate.
Of course, the electron charge and proton charges are equal in magnitujde, so their forces are comparable. The key ingredient is that the proton to electron mass ratio is almost 1000, and the typical atmospheric gas atom has about the same number of neutrons as protons. As a result the nuclear to electron cloud mass ratio is about 2000:1, so the net repulsive forces that eventually push the atoms or molecules apart again,result in the electon cloud accelerations being around 2000 times the nucleus accelerations. So for all practical purposes as far as EM radiation is concerned, the positively charged nuclei, barely accelerate at all, compared with the electrons. The result is EM radfiation from the accelerated electrons, with only about 0.05% cancellation due to the nuclear acceleration.
From the “Astronomy on line” web site I found this simple statement:-
“”””” Thermal Radiation – Back to Table of Contents
Did you know that any object that contains any heat energy at all emits radiation? When you’re
camping, if you put a large rock in your campfire for a while, then pull it out, the rock will emit
the energy it has absorbed as radiation, which you can feel as heat if you hold your hand a few
inches away. Physicists would call the rock a “blackbody” because it absorbs all the energy that
reaches it, and then emits the energy at all frequencies (although not equally) at the same rate it
absorbs energy.
All the matter in the known universe behaves this way.
Some astronomical objects emit mostly infrared radiation, others mostly visible light, others
mostly ultraviolet radiation. The single most important property of objects that determines the
radiation they emit is temperature.
In solids, the molecules and atoms are vibrating continuously. In a gas, the molecules are really
zooming around, continuously bumping into each other. Whatever the amount of molecular
motion occurring in matter, the speed is related to the temperature. The hotter the material, the
faster its molecules are vibrating or moving.
Electromagnetic radiation is produced whenever electric charges accelerate—that is, when they
change either the speed or direction of their movement. In a hot object, the molecules are continuously
vibrating (if a solid) or bumping into each other (if a liquid or gas), sending each other
off in different directions and at different speeds. Each of these collisions produces electromagnetic
radiation at frequencies all across the electromagnetic spectrum. However, the amount of
radiation emitted at each frequency (or frequency band) depends on the temperature of the
material producing the radiation. “””””
I can’t think of any group of Physicists, whose view on EM radiation Physics is as all encompassing as the Astronomy community. The EM radiation spectrum is their laboratory.
Compared to Astronomers, climate physicists are babes in arms; so I’ll take the Astrophysics field’s word for it, that atmospheric gases do indeed radiate a thermal continuum EM LWIR spectrum, as a part of the energy flow in the earth atmosphere.
GHG molecules that produce and absorb LWIR radiation due solely to molecular resonance processes, are not all that atmospheric LWIR radiation is all about.
So the amount of CO2 remaining in the atmosphere is related to the size of the drain into the sink. It can be a giant sink, but if the drain size is small (low flow rate), then emissions will accumulate in the atmosphere and should be detectable. But we can see from the data that the ocean is both a source and a sink. And we know from the data that the reaction rate is very high, dwarfing emissions. So we must conclude that the the size of the opening to this source / sink is very large. This is the part that is unmistakeable in the data. If that is true, then the total accumulation MUST be mostly related to temperature and the ocean’s equilibrium level.
You’re missing the mechanism for the sink – carbon dioxide is heavier than air, takes work to get it to rise in air and will always displace air to sink to the surface, and, readily joins with water to form carbonic acid, i.e. rain. It’s a constant turnover, ‘accumulation’ doesn’t factor in, the term/concept here is residence time.
I used the maximum slope I could find the in seasonal data to find that the rate of exchange between oceans and atmosphere must be faster than 7.2 years (otherwise this slope could not be reached). I suspect it is actually much faster than that.
http://www.c3headlines.com/2009/09/the-liberal-attack-on-science-acorn-style-the-ipcc-fabrication-of-atmospheric-co2-residency-time.html
Note though, the IPCC line is the ‘propaganda’ line; when delving into the actual figures produced by the IPCC, hidden in the morass of information, the figures are different:
Edim,
“I agree with the arguments in your presentation. What do you think of the similarity of the variations in global sea ice and CO2 rate of change (double peak)? Coincidence?”
The double peak in the global sea ice is the results of adding opposing cycles of different amplitude that are slightly out of sink. I have found in curve fitting the CO2 annual variation that there are possibly two cycles with different shapes operating at the same time. One has the modified triangle form cos(2*PI*t+b)+cos(2*(2*PI*t+b))/4+cos(3*(2*PI*t+b))/9. The other has the sawtooth form sin(2*PI*t+c)-sin(2*(2*PI*t+c))/4. Together, these two functions can give you the double peak. In multiple regression analysis, the coefficients for these two functions vary systematically with latitude, but not longitude. The maximum amplitudes are at Arctic sites. There is hardly any amplitude around 10S. In the southern hemisphere, the direction changes and a much smaller maximum amplitude shows up around the edge of the ice. The climate behavior at the poles are poles apart in many ways.
well slioch, i’m not going in for this tit for tat “my source is more impartial than yours”. or even a compromise that 121GT per annum is too much whilst 145MT is too little, Since your link comes from the said source, the British Geologic survey under that guise of certainty in what is obviously an unresearched field, with the title of “volcanic contribution to carbon cycle” subheaded “sustainable and renewable energy”, it comes form the same hymn sheet that Schmidt and consensus bearing climate scientists opt for – assuming that you’re referring to point 7 in the contents of the British geological survey paper. I assume its therefore a fairly recent document What is amiss is that terrestrial and submarine volcanoes emit large amounts of *fossil fuel* c02 when they are not active or erupting, so they are not measured, and this process is continual ,and goes back a long period in time -that might go some way to understanding why there’s such a huge reservoir of c02 in the oceans – assuming that a heck of a lot of it has the identical isotope of anthropogenic co2, then any appraisal of aerial co2 is pure guesswork.
as an addendum, I don’t think that guesswork from a consensus, which makes assumptions from a position of a lack of knowledge or research is what goes on between the mantle and the oceans, or inferences from non-consensus scientists are going to provide real data from natural c02 sources from the earth,
Fred,
I understand where the double peak in global sea ice comes from. My question is if this double peak causes the same in dCo2? Probably not.
Ferdinand:
To quote the nightmare of someone else, “I’m back”.
I am now looking at your points to me at August 7, 2011 at 1:06 am
You say;
“Please Richard, the influence of temperature on the CO2 rate of change is known for decades. It is acknowledged by sceptics (Dr. Spencer and many others and now Prof. Salby) as well as by warmers. My information is from a “warmer” I respect for his scientific integrity: Pieter Tans, head of the NOAA unit which runs the baseline stations where CO2 is measured.”
Firstly, your statement is misleading. The people you cite do NOT agree on “the influence of temperature on the CO2 rate of change”. Indeed, Salby concludes that temperature probably governs atmospheric CO2 concentration in his presentation which is the subject of this thread.
You choose to accept the work of Tans (whose integrity I have never questioned).
But I choose to accept the empirical data. It shows the exchange of CO2 between ocean surface layer and the air can be much faster than is needed to provide all the observed rate of rise in atmospheric CO2 concentration since measurements began at Mauna Loa in 1958. Michael D Smith gives a very good explanation of this in this thead at August 6, 2011 at 5:34 pm .
However, that information is short-term. If CO2 were to be released from the ocean surface layer over a long period then the surface layer may become depleted in CO2. In that case, the rate controlling factor would be how fast CO2 is supplied to the surface layer from deep ocean, but that supply rate is not known.
So, if the short-term ocean/air exchange rate can be sustained then the observed temperature changes could be expected to have provided the increase to atmospheric CO2 concentration which is observed at Mauna Loa since 1958.
But
if the short-term ocean/air exchange rate denudes the ocean surface layer of CO2 then large exchange rates may only occur for one or two years and then CO2 supply from deep ocean would limit the rate at which atmospheric CO2 concentration could rise. If that possibility is true, then the CO2 in the ocean surface layer is sufficient for annual fluctuation in-and-out of the ocean and occassional ENSO fluctuations, but only the rate of CO2 supply from deep ocean could enable the increase to atmospheric CO2 concentration which is observed at Mauna Loa since 1958. However, as I said, we do not know that supply rate. It could be sufficient to permit the observed rise in atmospheric CO2 since 1958. Alternatively, the supply rate from deep ocean may be so little that – for all observable purposes – it could be considered to be zero.
Hence, I stand by my statement that said, “The temperature changes could be the cause of all or none of “the variability in sink rate / increase speed”.
Then you repond to my having disputed your assertion that
““temperature changes largely compensate each other over 2-3 years”.
by saying;
“Simply make a 3-years moving average. I haven’t done that, but have a look at the 21 year averaging of the temperature record:
ftp://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_emiss_increase.jpg
Over time you see flat periods and periods where the average temperature increases. That means that the short term responses in both directions fully compensate each other in flat periods and there is a residual plus in upgoing periods.
Sorry, but that is a ‘non sequitor’.
You said the effects of temperature “largely compensate” over 2 to 3 years.
You now try to justify that by claiming the “short term responses” compensate within 2 to 3 years. Well, they are “short term”, but so what?
Importatly, you admit “there is a residual plus in upgoing periods”.
That “residual plus” is the rise in atmospheric cO2 concentration since 1958 that we are talking about”!
I say we need to determine its cause which is probably the temperature rise.
You say you know it is caused by the anthropogenic emission.
It is not reasonable to reject temperature change as a cause of the rise in atmospheric CO2 concentration because “temperature changes largely compensate each other over 2-3 years” when only the short term changes do that and the longer term changes are the possible cause of the rise.
Richard
PS I apologise that I could not give this reply until now but I am sure you know why.
Myrrh says:
August 7, 2011 at 1:59 pm
Thanks for the info. So it looks like I’m on the right track that the turnover must be much faster than the maximum seasonal slope in CO2 would indicate (maybe this is where the 4x factor comes from). I’ll read up and see what comparisons I can make. If turnover is that fast, I’m sorry, but there isn’t a snowball’s chance of accumulating much CO2 in the atmosphere. We just don’t have enough supply to do that, we can’t burn it fast enough. Unless we make some severe restrictions on ocean mixing, like it only affects the first few meters.
Agree rain is a good way to scrub CO2, but it only works in one direction. The rate is large in both directions. Surface absorption must be really efficient too.
The mass of CO2 is meaningless at normal temperatures on earth. Diffusion will mix CO2 (and any other gas, even Xenon) to an even distribution so fast you won’t believe it. It can’t “settle out”, it’s constantly being bounced around and mixed by the property of having temperature. The molecules will be a long way away from where they started before you know it. I could see gravity taking over at something near absolute zero, but, really, for all practical purposes, gravity has nothing to do with it. I don’t remember the substance, but the science teacher opens a bottle of something smelly with a very small molecule size, and you could smell it in the back of the room in a few seconds. The lightest molecules do diffuse the fastest, but they ALL diffuse too fast to prevent rapid mixing.
Agree the IPCC has their foot on the scale. I loved Susan Solomon’s study saying the effects will last thousands of years… Right. If we could only find enough carbon to burn.
Busy week, but I’ll work on some equations and see if I can figure out what the maximum human signal that could be registered would be given the turnover rates. The rest must be temperature. There is a very slightly rising rate, so maybe that is related to both increasing emissions and ocean equilibrium pushing back, and from there, we might be able to deduce mixing depth. It’s a stretch, probably too many unknowns. It’s no wonder they have have to press on the scale so hard, with fast turnover, AGW implodes. Again.
Edim,
“I understand where the double peak in global sea ice comes from. My question is if this double peak causes the same in dCo2? Probably not.”
Proximity of the CO2 measuring sites to the sinks affects the amplitude of both the observed cycle types but not the same. I don’t think you will be able to see double peaks in the Southpole CO2 data; and possibly not in any of the southern hemisphere data.
Ferdinand Engelbeen says:
August 7, 2011 at 8:37 am
Huh? In 1998 atmosphere increased by 5ppm. Anthropogenic emission was 3ppm. Where’d the other 2ppm come from if not from El Nino warming of the Pacific? Moreover, where did it go if it didn’t remain resident in the atmosphere? I believe this demonstrates the ocean can be a net source of CO2 in any given year. The question this raises is whether it can be a net source over 50 years. Or 250 years. Salby believes it can and the only thing standing in the way of Salby’s hypothesis is C12/C13 ratios which are held up by climate boffins as confirmation that accumulation is anthropogenic in nature. I never found the C12/C13 ratio a credible confirmation and now there’s some support for my lack of confidence of it in the literature.
Again this is not to say CO2 rise over the past 250 years is NOT anthropogenic in origin. I’m just saying there’s nothing to prove or disprove that claim. There is correlation, compelling correlation IMO, but correlation is not causation.
Rainwater has the ability to wash CO2 out of the atmosphere, and may be an important mechanism in the ocean – atmosphere exchange.
Rough estimate of CO2 in rainwater is on the same order as the TOTAL annual CO2 atmosphere exchange.
From a global water balance, I found an estimate of total global rainfall that came to about 100,000 Gt/yr (as H2O) over land, and 400,000 Gt/Yr over the oceans. CO2 is fairly soluble in water, and the colder the water, the more CO2 it can hold. The CO2 in ‘natural’ rainwater lowers the pH from neutral 7 to around 5.7. Since the observed pH of rainwater is similar to calculated pH at CO2 saturation, that suggests that rainwater, if not saturated with CO2, is fairly close to holding as much as it can. At saturation, the dissolved CO2 in water would be 0.23 g CO2/100g water at 10 deg C, at 15 deg C dissolved CO2 is 0.20 g/100g and at 20 deg C the dissolved CO2 would be 0.18 g/100g.
Global average air temperature is around 15 deg C, but that varies widely over the planet, and of course the temperature of rainwater in the top of a cloud may not be the same as an average ground temperature. Just to get a rough idea of the magnitude of CO2 in rainwater, I did a couple calculations using the CO2 solubility at 20 deg C (warmer, holds less CO2) and at 10 deg C (colder, holds more CO2). Rainfall over land calculates as 49 to 68 Gt CO2/yr (as Carbon so we can compare to the atmospheric CO2 estimates). And for the ocean rainfall, it comes to 183 Gt/yr to 252 Gt/yr (as carbon). The land rainfall could end up ’stored’ in a river or lake, go into the soil or plants, or could splat on a parking lot and re-release the CO2 to the air when the water evaporates. My guess is the ocean rainfall could most likely be incorporated into the ocean and the CO2 with it (there is way more CO2 dissolved in the oceans than ‘free’ in the atmosphere).
So how much is that compared to CO2 estimates in the atmosphere? For CO2 in the atmosphere (around 380 ppm at the time I did the calculation) it was estimated that the atmosphere contained about 750 Gt (Gt =gigatons, CO2 expressed as equivalent amount of Carbon). The amount of CO2 that is cycled into and back out of the atmosphere is estimated to be on the order of 150 to 220 Gt per year due to a variety of natural (volcanism, forest fires, vegetation decay, ocean offgassing, etc) and man-made (burning organic fuels, etc) sources. The man-made CO2 totals come to about 6-8 Gt (as carbon) each year, which is only about 3 to 5% of the total emitted CO2. Atmospheric CO2 is also removed via plant growth, absorption into the oceans, etc. The net increase in atmospheric CO2 appears to be around 1.5 ppm per year, which is about 3 Gt/yr (as carbon).
Note that these estimated rainfall CO2 values are about the same size as the total carbon cycle estimates of 150 to 220 Gt per year. This does not necessarily mean that the estimates (theirs or mine) are incorrect.The rainfall CO2 may show up in other parts of the global estimates such as an overlap of the land rainfall CO2 ending up in the plant growth CO2 estimates. Similarly we know that as ocean water warms, it releases CO2, and since we don’t have very good measurements of that released CO2, it could be that rainfall is just returning some of that unmeasured CO2 to the ocean for a ‘net’ value much lower than my calculation. And of course, my estimates include assumptions about CO2 saturation in rain water, and about the temperature of rain water. Snow or other frozen forms of precipitation may not hold much, if any CO2.
Still, even if my estimates are 10 times too high, there is potentially still a lot of CO2 in rain water. It appears that rainwater has more than enough capability to remove all man-made CO2 on an annual basis. However, whether it stays removed is regional and situational.
Dave in Delaware says:
August 7, 2011 at 4:19 pm
Here is something for you to think about. Cold water is the best sink for CO2. As sea water warms as it crosses the equatorial Pacific, it not only releases CO2 into the atmosphere, it evaporates a lot more water at the same time. That vapor rises and cools and forms clouds. That cold cloud water absorbs CO2. Some of those clouds tower into the stratosphere and the water freezes and releases CO2. Some falls as rain into warmer air. Some of that rain evaporates and releases CO2. The rest returns to the ocean. This cycle may occur many times before it finally delivers CO2 to the frigid polar waters where it sinks in brines caused by freezing ice. A side note, these many evaporation/condensation/freezing cycles will tend to fractionate C12/C13 leaving more of the lighter in the stratosphere and returning the heavier to the ocean. Now see if you can figure out those rates.
@Fred Haynie
interesting cycle description, had not considered fractionation in the atmosphere.
I have been thinking more about long term Thermohaline circulation – We often hear about CO2 being absorbed and drawn down in the frigid polar waters, but seldom mention of where that circulation comes back up to the surface in the Indian or Pacific oceans, perhaps on the order of 800+ years later.
The returning waters will be very cold and under pressure, so they bring extra CO2 when they surface (extra as compared to an equal volume of ‘surface’ ocean). And from what I have read, the deep ocean CO2 is enriched in C12 (lower C13, even less C13 than you would get from fossil fuels). So the returning deep ocean CO2 would tend to dilute out the atmospheric C13, similar to a fossil fuel, but from a ‘natural’ source. Much like Prof Salby has described in the lead article here.
There would also be an ENSO link – more cold upflow off the coast of South America in some phases of ENSO (CO2 released at lower surface pressure), followed by warming of those waters as an El Nino sloshes back across the Pacific, potentially releasing more of that returning deep ocean CO2.
P Wilson says:
August 7, 2011 at 8:55 am
Furthermore, there is no fingerprint by which we may distinguish fossil fuel CO2 from volcanic CO2.
Sorry, here your reference (even if he is a geologist) is wrong. Most of all active volcanoes and vents emit CO2 with high 13C content (zero +/- 10 per mil). That is because many volcanoes recycle oceanic carbonate deposits which have that 13C/12C ratio. Magmatic CO2 indeed is lower in 13C/12C ratio, and that can be used to know the origin of the CO2.
But the main point is: can volcanoes be the origin of the recent increase in the atmosphere? Hardly: the mass balance gives an increase in the atmosphere which is less than the human emissions. That means that regardless what volcanoes do, even if they emit 100 times more CO2 than humans, all the natural emissions, including volcanoes, are more than compensated by natural sinks, wherever that may be.
Further, there is no indication of increased volcanic activity over the past 150 years, compared to any period before, to the contrary.
And last but not least: any increased natural activity, including volcanoes, should follow the human emssions at an incredible fixed rate, as that is what is observed.
Myrrh says:
August 7, 2011 at 1:59 pm
Again and again, so many are confusing residence time with excess decay time. Residence shows how long any CO2 molecule (whatever the origin) resides in the atmosphere, before being exchanged with another molecule from the oceans or vegetation. The exchange rate or throughput is inflow (or outflow) / mass in the atmosphere. That is more or less known: 150/800 GtC, or near 20% of all CO2 in the atmosphere is exchanged with other reservoirs per year. That gives a residence time of about 5 years.
That doesn’t give us any clue how long it takes to remove an extra amount of CO2 injected into the atmosphere (whatever its origin, human, volcanoes, warming oceans,…).
The excess decay rate is governed by the sink rate, which currently is only 4 GtC/year. That means that of the 800 GtC carbon currently in the atmosphere (of which 200 GtC extra since 1850), only 4 GtC/year is removed. But humans emit 8 GtC per year! Thus even if we stop all emissions today, the reduction of the extra amount of CO2 needs far more time than the 5 years residence time (but far less than the hundreds of years from the IPCC), about 38 years half life. See:
http://www.john-daly.com/carbon.htm
Richard S Courtney says:
August 7, 2011 at 2:26 pm
Firstly, your statement is misleading. The people you cite do NOT agree on “the influence of temperature on the CO2 rate of change”. Indeed, Salby concludes that temperature probably governs atmospheric CO2 concentration in his presentation which is the subject of this thread.
Not only does Salby agree with the influence of temperature on the CO2 rate of change, it is the very base for his notion that that also influences the total CO2 concentration, based on the fastest rate of change seen in the record.
And there he goes wrong.
But I choose to accept the empirical data. It shows the exchange of CO2 between ocean surface layer and the air can be much faster than is needed to provide all the observed rate of rise in atmospheric CO2 concentration since measurements began at Mauna Loa in 1958.
That is true and false and also what Salby expects: any temperature increase (or decrease) has a longer term influence on CO2 levels. But that can’t be right, because it violates Henry’s Law. If we start with a steady state equilibrium between atmosphere and ocean surface, then an increase of 1 degr.C gives an increase in equilibrium partial pressure of the oceans of 16 microatm. The oceans surface (the “mixed” layer) therefore emits more CO2, until the atmosphere also reaches an extra 16 microatm increase. At that moment a new equilibium is reached and the flows back and forth between the atmosphere and the mixed layer are equal.
16 microatm (~ 16 ppmv) extra in the atmosphere needs only 32 GtC, or the equivalent of four years human emissions.
Moreover, despite the temperature increase of the oceans, the atmospheric increase was 100 ppmv (80 ppmv since Mauna Loa started), far higher than expected from the oceans temperature increase. Thus the oceans are not the source of the extra CO2 in the atmosphere, they are a net sink. That is measured as an increase of total CO2 (CO2+-bi-carbonates, DIC) in the ocean’s mixed layer by millions of ships samples and a few long term series (Bermuda and Hawaii).
That “residual plus” is the rise in atmospheric cO2 concentration since 1958 that we are talking about”
Over the longer term, we see that the period 1945-1975 was slightly cooling, the period 1975-2000 was warming and the period 2000-now is flat. Despite that, there was a steady increasing increase of CO2 in the atmosphere over all three periods, whithout any visible influence of the residual temperature decrease/increase/flat level. But the increase in the atmosphere follows the accumulated emissions at an incredible constant ratio…
That is a strong indication that the longer term (2-3 years) trend is caused by the emissions, where temperature has a huge influence on short term variations around the trend, but hardly any on the trend itself.
P Wilson says:
August 7, 2011 at 3:40 am
….
Since oceans regulate CO2 in the air to the most minute degree, any real increase is due to warmer oceans releasing more. There is no justification in reading human activity into an increase
Since the start of the satellite era in 1979 MSU temps have risen by ~0.4 deg – less over the oceans. How much has SST risen? Certainly no more than 0.4 deg. Let’s be generous and call it 0.4 deg. In 1979 atmospheric CO2 levels were ~336 ppm; In 2010 they were ~390 ppm. That’s an increase of more ~54 ppm in the last 30 years. Let’s call it 50 ppm.
Now then, we know temperature and SST, in particular, influences the CO2 growth rate in the atmosphere. We can see this in Michael Smith’s graph (posted earlier). Ferdinand Englebeen reckons the short term relationship is ~4 ppm/deg C. This looks to be about right. The net growth over an El Nino year can be as much as ~2 ppm more than over a La Nina year. Ferdinand also cites a longer term relationship of ~8ppm/deg C – a figure which is supported by Law Dome data (the most reliable ice core data).
If ocean warming were responsible for the post-1979 increase in atmospheric CO2, the relationship would need to be ~125 ppm/deg C i.e. (50/0.4). Things are no better if we look at the longer term. The post-1900 CO2 increase is ~100 ppm. Temperatures have risen ~0.7 deg over the same period of time. This yields a relationship of ~143 ppm/deg C . These figures are so far removed from reality they are simply not credible. To show how ridiculous they are, consider CO2 levels during the recent interglacial period.
Even if we accept Richard Courtney’s leaf stomatal CO2 level of ~330 ppm, this still leaves us with a bit of problem with the previous ice age when temperatures were ~5 deg lower. Using any of the relationships based on modern observations implies a fall in CO2 concentrations of at least 625 ppm – leaving us with a CO2 level of around MINUS 300 ppm .
It’s complete nonsense and the whole episode is destroying the credibility of genuine climate scepticism.
The logic of is claiming that the 3% of CO2 which humans put into the atmosphere accumulates over time to 30%, while the 97% of CO2 which nature adds to the atmosphere does not accumulate and in fact shrinks to 70% of the total is [snip]….
You’re (completely) failing to understand what’s happening. Many people use the bath-tub analogy to explain the concept but I’ll use the CO2- atmosphere mode using simple numbers.
Imagine a pre-industrial time where there are 600 units of CO2 in the atmosphere. During the annual carbon cycle, 120 units are emitted from the biosphere and 120 units are absorbed. Some points to notice here:
1. Co2 in the atmosphere remains in equilibrium at 600 units.
2. The average life-time of a unit in the atmosphere is 5 years (this ties into earlier discussions).
Suppose we now introduce a new (non-naural) source of CO2 which adds 2 units a year (less than 2% of the natural emissions). The carbon cycle continues whereby 120 units are emitted and 120 units are absorbed but the atmospheric level has increased to 602 units. After 10 years the level is 620 units and after 100 years it’s 800 units. Another point to notice.
Even though the non-natural source is less than 2% of the natural source, it has, over time, increased the atmospheric concentration by 33%.
Things are a bit more complicted than I’ve just described but that’s the basic concept in a nutshell.
Dave Springer says:
August 7, 2011 at 3:27 pm
In 1998 atmosphere increased by 5ppm. Anthropogenic emission was 3ppm. Where’d the other 2ppm come from if not from El Nino warming of the Pacific?
The 1998 increase in the atmosphere was 2.6 ppmv, human emissions 3.0 ppmv. But even if the increase was higher than the human emissions, then the natural imbalance was only 2 ppmv in one year, as your figures give. In 1973, we had the same scenario, with a possible contribution by nature. All other years, nature was a (strong) sink for CO2. Averaged over 50 years, nature was a sink for about halve the mass of the emissions. Thus the true contribution of nature to the increase over the past 50 years was negative.
This demonstrates the ocean can be a net source of CO2 in any given year. The question this raises is whether it can be a net source over 50 years. Or 250 years.
It was in the period 250-110 years ago, when humans were emitting (very) small amounts of fossil fuels. It was probably not anymore in the period 110-50 years ago and it was definitely not in the past 50 years.
Salby believes it can and the only thing standing in the way of Salby’s hypothesis is C12/C13 ratios which are held up by climate boffins as confirmation that accumulation is anthropogenic in nature.
If Salby had done a little literature search about the oxygen balance, he would have known that the only other source of low 13C, the biosphere, is a net aborber of CO2, thus of 12CO2 and thus not the cause of the decline in 13C/12C ratio, leaving only fossil fuel burning as cause.
Dave Springer says:
August 7, 2011 at 3:27 pm
Ferdinand Engelbeen says:
August 7, 2011 at 8:37 am
………….
Huh? In 1998 atmosphere increased by 5ppm.
No it didn’t. The increase in 1998 was 2.98 ppm. However, the point is irrelevant anyway. Can you please get this and understand it.
We know that there is year to year variation in CO2 growth rate which is temperature driven to a significant degree.
That is not – and never was – in dispute. If there were no human CO2 emissions CO2 levels would not remain in exact equilibrium at ~280 ppm. Over a decade annual readings might be as high as 282 ppm or as low as 278 ppm; over longer periods the range could be even wider (up to 10 ppm perhaps). We know this and can explain it.
HOWEVER, we can’t explain the medium to long term CO2 trend
While we can explain much (not all) of the 2.98 ppm rise in the El Nino year of 1998 and much (not all) of the smaller 0.46 ppm rise in the Pinatubo-affected year of 1992 as results of temperature changes, we cannot explain
1. The ~24 ppm increase since 1998 (temp change ~0.1 deg)
2. The ~53 ppm increase since 1979 (temp change ~0.4 deg)
3. The ~100 ppm increase since 1900 (temp change ~0.7 deg)
Ferdinand:
Thankyou for your response (at August 8, 2011 at 1:53 am) to my post (at August 7, 2011 at 2:26 pm).
As always, I appreciate that we can forcefully disagree without being disagreeable. But, with repect, your response does not address my points.
You do make one counter-argument to me when you say;
“That is true and false and also what Salby expects: any temperature increase (or decrease) has a longer term influence on CO2 levels. But that can’t be right, because it violates Henry’s Law.”
Sorry, but, NO!
The data clearly proves that Henry’s Law is not applicable in this case. Please read what I wrote.
The fact is that the change in atmospheric CO2 concentration at times of ENSO changes proves that Henry’s Law does not apply.
We can argue until ‘the cows come home’ as to why Henry’s Law does not apply in this case, but the data proves it does not. Therefore, any calculations based on Henry’s Law (including yours) are wrong.
And you again assert;
“Over the longer term, we see that the period 1945-1975 was slightly cooling, the period 1975-2000 was warming and the period 2000-now is flat. Despite that, there was a steady increasing increase of CO2 in the atmosphere over all three periods, whithout any visible influence of the residual temperature decrease/increase/flat level.”
But there was NOT “a steady increasing increase of CO2 in the atmosphere over all three periods”, and your assertion ignores what I have written.
At August 5, 2011 at 5:34 pm I wrote to Orson Olson saying;
“You say,
“However, a NOAA illustration of the Annual Mean Growth of CO2. Note the group by decade-and no relation to human emissions.
http://www.esrl.noaa.gov/gmd/webdata/ccgg/trends/co2_data_mlo_anngr.png “
Yes, and
compare those decadal averages shifted back in time ~30 years
to
mean global temperature (e.g. HadCRUT, see
http://www.cru.uea.ac.uk/cru/data/temperature/ )
Does that suggest anything to you?”
Then (at August 5, 2011 at 6:47 pm) he replied saying that it did provide him with the obvious suggestion; i.e. he said;
“Yes. It suggests delta-T is causing rising atmospheric CO2.”
Richard