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Is the ocean carbon sink sinking?

Filed under: — david @ 1 November 2007 - (Español)

The past few weeks and years have seen a bushel of papers finding that the natural world, in particular perhaps the ocean, is getting fed up with absorbing our CO2. There are uncertainties and caveats associated with each study, but taken as a whole, they provide convincing evidence that the hypothesized carbon cycle positive feedback has begun.

Of the new carbon released to the atmosphere from fossil fuel combustion and deforestation, some remains in the atmosphere, while some is taken up into the land biosphere (in places other than those which are being cut) and into the ocean. The natural uptake has been taking up more than half of the carbon emission. If changing climate were to cause the natural world to slow down its carbon uptake, or even begin to release carbon, that would exacerbate the climate forcing from fossil fuels: a positive feedback.

The ocean has a tendency to take up more carbon as the CO2 concentration in the air rises, because of Henry’s Law, which states that in equilibrium, more in the air means more dissolved in the water. Stratification of the waters in the ocean, due to warming at the surface for example, tends to oppose CO2 invasion, by slowing the rate of replenishing surface waters by deep waters which haven’t taken up fossil fuel CO2 yet.

The Southern Ocean is an important avenue of carbon invasion into the ocean, because the deep ocean outcrops here. Le Quere et al. [2007] diagnosed the uptake of CO2 into the Southern Ocean using atmospheric CO2 concentration data from a dozen or so sites in the Southern hemisphere. They find that the Southern Ocean has begun to release carbon since about 1990, in contrast to the model predictions that Southern Ocean carbon uptake should be increasing because of the Henry’s Law thing. We have to keep in mind that it is a tricky business to invert the atmospheric CO2 concentration to get sources and sinks. The history of this type of study tells us to wait for independent replication before taking this result to the bank.

Le Quere et al propose that the sluggish Southern Ocean CO2 uptake could be due to a windier Southern Ocean. Here the literature gets complicated. The deep ocean contains high concentrations of CO2, the product of organic carbon degradation (think exhaling fish). The effect of the winds is to open a ventilation channel between the atmosphere and the deep ocean. Stratification, especially some decades from now, would tend to shut down this ventilation channel. The ventilation channel could let the deep ocean carbon out, or it could let atmospheric carbon in, especially in a few decades as the CO2 concentration gets ever higher (Henry’s Law again). I guess it’s fair to say that models are not decisive in their assessment about which of these two factors should be dominating at present. The atmospheric inversion method, once it passes the test of independent replication, would trump model predictions of what ought to be happening, in my book.

A decrease in ocean uptake is more clearly documented in the North Atlantic by Schuster and Watson [2007]. They show surface ocean CO2 measurements from ships of opportunity from the period 1994-1995, and from 2002-2005. Their surface ocean chemistry data is expressed in terms of partial pressure of CO2 that would be in equilibrium with the water. If the pCO2 of the air is higher than the calculated pCO2 of the water for example, then CO2 will be dissolving into the water.

The pCO2 of the air rose by about 15 microatmospheres in that decade. The strongest Henry’s Law scenario would be for the ocean pCO2 to remain constant through that time, so that the air/sea difference would increase by the 15 microatmospheres of the atmospheric rise. Instead what happened is that the pCO2 of the water rose twice as fast as the atmosphere did, by about 30 microatmospheres. The air-sea difference in pCO2 collapsed to zero in the high latitudes, meaning no CO2 uptake at all in a place where the CO2 uptake might be expected to be strongest.

One factor that might be changing the pressure of CO2 coming from the sea surface might be the warming surface waters, because CO2 becomes less soluble as the temperature rises. But that ain’t it, as it turns out. The surface ocean is warming in their data, except for the two most tropical regions, but the amount of warming can only explain a small fraction of the CO2 pressure change. The culprit is not in hand exactly, but is described as some change in ocean circulation, caused maybe by stratification or by the North Atlantic Oscillation, bringing a different crop of water to the surface. At any event, the decrease in ocean uptake in the North Atlantic is convincing. It’s real, all right.

Canadell et al [2007] claim to see the recent sluggishness of natural CO2 uptake in the rate of atmospheric CO2 rise relative to the total rate of CO2 release (from fossil fuels plus land use changes). They construct records of the atmospheric fraction of the total carbon release, and find that it has increased from 0.4 back in about 1960, to 0.45 today. Carbon cycle models (13 of them, from the SRES A2 scenario) also predict that the atmospheric fraction should increase, but not yet. For the time period from 1960 to 2000, the models predict that we would find the opposite of what is observed: a slight decrease in the atmospheric fraction, driven by increasing carbon uptake into the natural world. Positive feedbacks in the real-world carbon cycle seem to be kicking in faster than anticipated, Canadell et al conclude.

There is no real new information in the Canadell et al [2007] analysis on whether the sinking sink is in the ocean or on land. They use an ocean model to do this bookkeeping, but we have just seen how hard it is to model or even understand some of the observed changes in ocean uptake. In addition to the changing ocean sink, drought and heat wave conditions may change the uptake of carbon on land. The infamously hot summer of 2003 in Europe for example cut the rate of photosynthesis by 50%, dumping as much carbon into the air as had been taken up by that same area for the four previous years [Ciais et al., 2005].

The warming at the end of the last ice age was prompted by changes in Earth’s orbit around the sun, but it was greatly amplified by the rising CO2 concentration in the atmosphere. The orbits pushed on ice sheets, which pushed on climate. The climate changes triggered a strong positive carbon cycle feedback which is, yes, still poorly understood.

Now industrial activity is pushing on atmospheric CO2 directly. The question is when and how strongly the carbon cycle will push back.

Canadell, J.G., C.L. Quere, M.R. Raupach, C.B. Field, E.T. Buitehuis, P. Ciais, T.J. Conway, N.P. Gillett, R.A. Houghton, and G. Marland, Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks, Proc. Natl. Acad. Sci. USA, doi 10.1073, 2007.

Ciais, P., M. Reichstein, N. Viovy, A. Granier, J. Ogee, V. Allard, M. Aubinet, N. Buchmann, C. Bernhofer, A. Carrara, F. Chevallier, N. De Noblet, A.D. Friend, P. Friedlingstein, T. Grunwald, B. Heinesch, P. Keronen, A. Knohl, G. Krinner, D. Loustau, G. Manca, G. Matteucci, F. Miglietta, J.M. Ourcival, D. Papale, K. Pilegaard, S. Rambal, G. Seufert, J.F. Soussana, M.J. Sanz, E.D. Schulze, T. Vesala, and R. Valentini, Europe-wide reduction in primary productivity caused by the heat and drought in 2003, Nature, 437 (7058), 529-533, 2005.

Le Quere, C., C. Rodenbeck, E.T. Buitenhuis, T.J. Conway, R. Langenfelds, A. Gomez, C. Labuschagne, M. Ramonet, T. Nakazawa, N. Metzl, N. Gillett, and M. Heimann, Saturation of the Southern Ocean CO2 sink due to recent climate change, Science, 316 (5832), 1735-1738, 2007.

Schuster, U., and A.J. Watson, A variable and decreasing sink for atmospheric CO2 in the North Atlantic, J. Geophysical Res., in press, 2007.

680 Responses to “Is the ocean carbon sink sinking?”

  1. 101
    Dan W says:

    Rod B (88) Carbonaceous rocks were at one time a huge carbon sink (when they were laid down). Now as they decompose they once again release their carbon. Mankind is facilitating this decomposition by mining, grinding and spreading limestone on our fields to neutralize the PH of the soil. This is one of the reasons agriculture is considered to be so “carbon intensive”.

  2. 102
    Les Porter says:

    Basically I am way way way late in deciding to post here once again.

    But here is the conversational part: and then we get to the main course below.

    Yes. After the last ice age and everyone of them, we saw an increase in atmospheric CO2. We do not know exactly where it ALL came from, but a warming ocean must account for a very very large part of it. That is, that within the boundless deep turns again home. That was the 800+/- year lag to the CO2 rise when the ice went off. It brought CO2 hanging around in the cold air at 180-190 ppmv (or less) to nearly 300 ppmv for some interglacial eras. Roughly as much as we have now pumped into the air, that is: 384 minus 300 equals 84 ppmv. So right now, with 384 ppmv in the air, can we expect additional ocean release in less than 800 years (200-400) that is now still entrained in the ocean? I believe (like an act of faith) that when the ocean reaches a punctuated equilibrium with the CO2 heated air, we will have experienced vast amounts of ocean embedded and buffered CO2 released to the air. But none of us will be around to validate that conjecture I posit on faith alone.

    Main Course:

    But. Initially when I read Sarah’s query and David’s response, I was concerned. David’s post is great and has the scientific conservative tone of an active player in the field.

    Then Sarah . . .

    #7 sarah Says:
    1 November 2007 at 5:24 PM

    I read this site regularly, although I have no science background. So I’m pretty hesitant to comment. But this especially sounds so dire. How much do you, as scientists steeped in this research, feel that human life on this planet has a fragile future at best? (I realize this is a broad question, so if it’s not applicable, please delete it.)

    [Response: Don’t despair. If nothing else, it’s unproductive. The technology exists to cut CO2 emissions to safe levels at reasonable cost. David]

    OK. Don’t despair (yet.) I agree. But the next statement which alludes to affordable technology and emissions at safe levels — disturbs me as it should many — and I see it did.

    What on earth is the safe level of CO2 emission? USDA published a figure once saying the average human exhales 900mg of CO2 — and annually if you captured that CO2, extracted the C from it and used some vapor deposition form of layering it in diamond form you would end up with almost a cubic foot of diamond for every person. In other words, and I did a post on it, you exhale enough CO2 to make a cubic foot of diamond.

    But the only safe emission level has got to be what is capable of sustaining a relative balance of C to maintain the temperature range for life on the planet. Right now, with the excess — it looks like the biological geological limit is the rough depth of the sawtooth in say the record from Mauna Loa.

    That is why REALCLIMATESOLUTIONS.ORG needs to get into the act and explain how we get back to whatever stable level we need to arrive at for life species to be at a sustainable level — not the IPCC 450, 550, 700 or more levels “pleasant” to business interests.

    This stuff IS going to be in the air for millenia unless real efforts are made to remove it, let alone stabilize it. Yeah, I’d like to see the real effort in removal and sequestration. Coupled to a bio-neutral level of emission.

    If you ever read Larry Niven, the difficulty of civilization is getting rid of the heat. Here the CO2 is part of that heat problem

    Obviously the interplay between ocean and earth is climate. Tectonics is slow to push chips here and there, so for long periods of time the fluctuating interplay between land and sea reaches an equilibrium — until something like us can interfere with it.

    Life has had a good run, and could have as much as a billion years and maybe a hundred million years on top of that before the oceans begin to be lofted fully into the air and evaporate and rise to the warming Sun, H2 to Space, O2 to CO2. . .and Venus gets a sister. (not sure how long Venus’ H2SO4 clouds will last. They may be gone with a warming Sun by then. (Some students think it will take as much as 2 billion years to get rid of Earth’s climate moderating water.) I do not think we can push the runaway greenhouse now with anything monkeys can do. But we could make life difficult for a few millions of years, by carelessly pushing this, then that, species to the point of extinction. Many sapiens will die too. The MIT meeting on tinkering with the climate is not in anyway realistic unless huge means of rapidly removing and sequestering the atmospheric CO2 are initiated. We need to do nothing to increase the CO2.

    For the record. The ocean sink is something likely to be filled and reversed if the ocean surface gets too, too warm — reaching the new equilibrium. Think of as a credible mechanism. You guys ought to talk it up.

  3. 103
    Ray Ladbury says:

    Re 89. Steve Reynolds, perhaps you can think of a motivation other than mendacity for a scientist repeating arguments he knows to be false (e.g. we can’t predict weather, so we can’t predict climate), for smearing the entire scientific community with the epithet “alarmist” while providing not one single example of a climate scientist attributing a particular weather event to climate change, and worst of all, painting those advocating mitigation of climate change as favoring continued poverty for the third world. I find this last particularly galling, having myself pointed out that development and climate mitigation are just two facets of the same problem–developing an economy that is both economically and ecologically sustainable.
    So if you can think of a lesser charge than mendacity for Christy to plead to that encompasses his rejection of evidence-based science, I’ll be happy to listen.

  4. 104
    Daniel C. Goodwin says:

    Re: 94 liking Biopact

    Some people like the idea of gobbling up the third world’s few remaining arable acres for the cultivation of biofuel crops. Not me. Look up the word “exacerbate” – it is not a synonym of “solve”.

  5. 105
    David B. Benson says:

    Daniel C. Goodwin (96) — The acres either are not arable or else are not required. Biopact’s total approach is actually most thoughtful.

    In any case, those growing and processing biofuel crops now have a cash income, something they (often) had not had before. Largely it is a win-win situation, although there are some troubles with this concept, principally in Southeast Asia.

    You really ought to read what Biopact has to say about themselves before just simply posting based on your mistaken assumptions.

  6. 106
    Pekka J. Kostamo says:

    RE 91: I understand the interest in raindrops as a mechanism of removing CO2 from the atmosphere.

    The raindrops have a large air/water surface area, so some of the atmospheric CO2 surely is absorbed and transported to the oceans, in addition to the direct air/sea interaction.

    Anyway, the 100 million year old carbon we burn does not disappear; it circulates and does its tricks.

  7. 107
    Pekka J. Kostamo says:

    About adaptation to climate climate change. It is frequently proposed that people with the probable problem of rising sea levels must just move somewhere else to live.

    Adaptation is easier if decisions are taken in good time. So let us right now make moving a bit easier for them. Let us terminate all visa and passport requirements and frontier formalities.

    This is not politically difficult. More real freedom for everyone, less big and unproductive government for the taxpayers to support. Who could possibly vote against it?

    That exists now in the USA, and that is the stated goal of the European Union.

  8. 108
    CobblyWorlds says:

    #28 on re Dr Christy,

    Very, very disappointing…

    He states:
    “The recent CNN report “Planet in Peril,” for instance, spent considerable time discussing shrinking Arctic sea ice cover. CNN did not note that winter sea ice around Antarctica last month set a record maximum (yes, maximum) for coverage since aerial measurements started.”

    NSIDC note that “The area covered by antarctic sea ice has shown a small (not statistically significant) increasing trend.” Whereas they say about the Arctic: ” This trend is a major sign of climate change in the polar regions and may be an indicator of the effects of global warming.”

    That’s only up to last year. More up to date data increasingly paints a different picture from that which Christy seeks to portray:
    Antarctic anomaly:
    Arctic anomaly:
    Comparing the 2 makes Christy’s statement look disingenuous to me. And that’s without labouring the perennial ice issue.

    Yes climate’s always changing, so what is the alternate theory that explains at least the warming of the last 30 years? At the same time as we have global warming, we have an agent which, under the best available theory, we expect to cause global warming. Without an alternate theory he’s just asking us to accept that the warming is a coincidence in favour of a handwaving “natural causes”.

    Anyway, here’s my nomination for Quote of the Week…
    “We discount the possibility that everything is caused by human actions, because everything we’ve seen the climate do has happened before.”John R Christy.

  9. 109
    Dan W says:

    Dr. Francis T. Manns (85) says:
    “I’m more concerned about te intellectual climate.”

    We worry about that too

  10. 110
    PaulM says:

    Let me blind you with this science…..Next summer, there is going to be a lot of poor people in semi-arid places who will be suffering from the heat…..excruciating heat, with no recourse except to suffer. No air conditioners, little water, and lots and lots of heat. The summer after that will get worse. More science…in Bangledesh, water will cover the city in our lifetime, with the lack of bulldozers expediting that fact. Eventually, the land masses on this planet will become red hot all over, perhaps in your grandchildrens lifetime, for you young ones. human suffering will become commonplace, like Mexico and Haiti, but all over in bulk… year.

  11. 111
    Hank Roberts says:

    > this planet will become red hot all over, perhaps in
    > your grandchildrens lifetime

    If you’re right, the grandchildren will live til the sun becomes a red giant and expands to reach Earth. That would be good.

    I suspect you’re wrong.

  12. 112
    Ike Solem says:

    Dr. Francis T. Manns (#85) said this at gristmill:

    “The effect of implimenting Kyoto would be disaster for you and yours. This is a case of needing to treat symptoms of global warming as they occur, if they are serious enough, without invoking Big Brother government to attack complex causes. The extremist model is not the only hypothesis. There are serious scientific questions. The spectal line of CO2 that is active in absorption is saturated. Additional CO2 cannot cause more warming.

    Francis T. Manns, Ph.D., P.Geo. (Ontario)”

    That notion was shown to be wrong well over 50 years ago. See The Carbon Dioxide Greenhouse Effect, Spencer Weart,

    The early experiments that sent radiation through gases in a tube, measuring bands of the spectrum at sea-level pressure and temperature, had been misleading. The bands seen at sea level were actually made up of overlapping spectral lines, which in the primitive early instruments had been smeared out into broad bands. Improved physics theory and precise laboratory measurements in the 1940s and after encouraged a new way of looking at the absorption. Scientists were especially struck to find that at low pressure and temperature, each band resolved into a cluster of sharply defined lines, like a picket fence, with gaps between the lines where radiation would get through.(24) The most important CO2 absorption lines did not lie exactly on top of water vapor lines. Instead of two overlapping bands, there were two sets of narrow lines with spaces for radiation to slip through. So even if water vapor in the lower layers of the atmosphere did entirely block any radiation that could have been absorbed by CO2, that would not keep the gas from making a difference in the rarified and frigid upper layers. Those layers held very little water vapor anyway. And scientists were coming to see that you couldn’t just calculate absorption for radiation passing through the atmosphere as a whole, you had to understand what happened in each layer — which was far harder to calculate.

    Manns also claims that cosmic rays and sunspots are the real reasons behind the observed temperature trends. This has all been reviewed on RC, in 2004 and 2006 and 2007. Still, the same arguments keep rolling out, over and over, even after being debunked again and again.

  13. 113
    Steve Reynolds says:

    93 Daniel C. Goodwin> On the question Ray Ladbury raises, viz. whether “those who advocate addressing climate change are condemning the third world to poverty,” I’m moved to chime in that I also find this line of argument (which Ray denounces) particularly disingenuous and disgusting.

    Why is it disingenuous?

    While ‘the most severe effects of climate-change occurring in the poorest regions of the world’, the most severe economic effects of any likely effective mitigation will also be born by the people of developing nations.

    For people who believe the economic effects of mitigation will be worse than the original problem (at least in short to medium term), aggressive mitigation is not in the interest of the poor.

  14. 114
    Mary C says:

    Re 89. This is another one of those statements that begs for more information. First of all, what is the evidence that you are citing? I keep hearing the argument, but those making it never seem to get around to explaining what supports it. In what ways will mitigation efforts make life worse in developing countries? Please be specific. Beyond that, I’m another person who finds the argument disgusting and disingenuous, given that those making it have not, to the best of my knowledge, previously demonstrated much concern with the problems of the developing world nor put any energy into solving those problems. They are using the argument solely in support of an ideological position. If no effort were being made toward climate mitigation, what actions would they propose and support right now to deal with the long-standing issues they have heretofore ignored?

  15. 115
    Bob Schmitz says:

    Re # 68 Diana Wills:

    You really scare me with the last paragraph of your comment! Burning forest might add CO2, but subsequently, new growth takes it back up again. Lumber will take some carbon out of the cycle, but what is the average life time of furniture or wooden construction? Most will end up in the atmosphere within 100 years. Without forests, tropical soils deplete within years, and drying out creates irreversible changes, if the soils are not completely eroded away first.
    Although the geographical distribution of the continents was different, life was doing great in the tropics during the Jurassic and Cretaceous. One of the reasons must have been the moderating influence of forests, providing evaporation (which cools directly, and indirectly through cloud formation). A great site to learn some basics of paleo climate is

  16. 116
    Bob Schmitz says:

    Re # 81 (sorry, not # 68), Diana Wills: about the paleo tropics:

    Herrera et al. (2005), ‘Warm (Not Hot) Tropics During the Late Paleocene: First Continental Evidence, American Geophysical Union, Fall Meeting 2005.


  17. 117

    Re #56: I read all too little about ocean thermal energy conversion. There is a near-unlimited supply of it, and it already works, providing many tropical island communities with power, cooling and sweet water.

    One nice thing about this technique is that it is preferentially available to countries near the equator, where most of the future growth in energy generating capacity is going to take place, both due to population growth and industrialization.

    Unfortunately that also seems to be the reason that little research money is going into it. What is happening is mostly small and private.

  18. 118
    Dave Rado says:

    #113, Steve Reynolds, are you really trying to convince us that you sincerely believe that if US citizens and businesses start to waste less energy and use more renewable energy, that will be cause subsistence farmers in Zambia and Bangladesh to suffer, and to suffer so much that the increases in droughts and floods that they are experiencing as a result of AGW pale in comparison? And please could you explain, in that case, why the US administration gave as its main reason for rejecting Kyoto the fact that countries such as Bangladesh and Zambia were not being asked to reduce their emissions under Kyoto?

  19. 119
    Lynn Vincentnathan says:

    RE #81 & “Regarding the use of passive solar, how does that work when things really heat up and you don’t get the cold winters? Doesn’t your house end up getting way too hot?”

    Ken’s house (#78) stays pretty cool in the summer. Summers do get very hot in Chicago’s far suburbs. And the sun is more overhead then, so it doesn’t go through his southern facing solar absorbing windows. Plus he has removable awnings, and deciduous trees that are bare in the winter, allowing sun in, and shady in the summer. His northern side has high, small windows, and is bermed almost up to them (but you can hardly tell, because of the beautiful shrubbery on the berms); this not only helps keep it warm when it’s cold, but cool when it’s hot outside.

    Finally his air-tight design & great insulation helps to keep cool, as well as warm, air in. (He also has a 4-stage filter system to bring outside, super-purified air in — 5 min every hour — so it is an extremely healthy environment.)

    My only thinking on this is after the 70s energy crunch, why haven’t ALL homes been built this way????!!!!

  20. 120
    Ray Ladbury says:

    Steve Reynolds,
    While Christy at least has his missionary background as support for his concern for the developing world, Lomborg and his fellow yuppie-scum seem to reserve their concern for when it can justify inaction on climate change. However, I see no evidence that Christy’s concern with the plight of the poor extended beyond his quest for their souls. In any case, anyone who has examined the problem in any detail has concluded that we cannot just look at current CO2 emissions, but must look at where they are growing most rapidly and where their growth is expected to pick up (first and second derivatives, if you will). This was the failure of Kyoto–it did not look at China and India, where economic growth was moribund when the treaty was initiated.
    Economic aid to develop green energy and transport infrastructures in developing countries will pay significant dividends both for their development and for stabilizing climate. Development is a part of the equation for sustainability, not a competitor.
    The entire argument that states that we must allow development, so we must do nothing about climate is false on technical grounds, false on economic grounds, false on humanitarian grounds and false on historical grounds.
    You state that the consequences of climate change will be less than the consequences of addressing it in the near term. However, climate consequences extend into the distant future and it is unwise to suppose that these threats can be met by simple technological fixes–particularly if we don’t allow time for those fixes to be developed. I can only presume that Christy posits a fiath-based solution.

  21. 121
    Nick Gotts says:

    Re #113 Steve Reynolds “While ‘the most severe effects of climate-change occurring in the poorest regions of the world’, the most severe economic effects of any likely effective mitigation will also be born by the people of developing nations.”

    I think we need argument rather than mere assertion here. Since poor countries (“developing nations” is for many of them a pusillanimous euphemism) produce much less greenhouse gas emission per capita than rich ones, any international agreement on reducing emissions (and without such an agreement, there’s no way they will be reduced) is bound to require greater reductions of rich countries. The latter are also far more dependent on high-energy and other high-emission practices. So why will the people of poor countries be more affected?

  22. 122
    pete best says:

    OFF TOPIC (slightly) – The dilemma of reporting climate change in the media.

    Two articles reported in the Telegraph (a co called right wing intelligensia newspaper in the UK) reports two climate articles.


    One story deals with the reality of climate change with a BAU and the other denies it is happenning completely.

    The battle of hearts and minds still goes on let alone implementing the solutions.

  23. 123
    Steve Reynolds says:

    Steve L> This has nothing to do with the science, but surely this is fascinating enough to warrant some discussion at another location (perhaps Steve R has a suggestion for an appropriate forum).

    I agree; RC is not the place for this discussion.

    I suggest:

    Fergus is certainly not on my side of the issue, but I think he welcomes discussion of economics and philosophy.

  24. 124
    Chuck Booth says:

    Re # 41 Eli Rabett “pCO2 is awful… How about changing over to Pco2 or some such.”

    Physiologists have long denoted CO2 partial pressure as PCO2 (with subscript 2). It is the chemists and chemical oceanographers who for some reason adopted pCO2. They also give their pCO2 values in units of microatmospheres, which I find annoying. But, then, I’m stuck in the world of torr (or mm Hg) and kcal, having never quite made the transition to S.I. units.

  25. 125
    SecularAnimist says:

    Joe Duck wrote: “Unfortunately many economic analyses suggest that mitigation costs are so great they’ll hurt development in the poor countries far more than they’ll help them with benefits from less pollution and less AGW.”

    With all due respeect, that is false. It is simply not true that “many economic analyses” suggest that. Nearly every economic analysis of the question strongly suggests the opposite. The overwhelming consensus of national and international organizations that work to overcome poverty in the developing world is that their efforts will be undermined and defeated by the effects of anthropogenic global warming, and that dealing with global warming is an absolutely essential requirement for improving human well-being in the developing world. The support that you claim for your opinion (“many economic analyses”) does not exist.

    Steve Reynolds wrote: ” … the most severe economic effects of any likely effective mitigation will also be born by the people of developing nations.”

    You offer no evidence to support the assertion that “the most severe economic effects” of mitigation will be to “developing nations”. In fact there is no such evidence and there is no reason to believe that this will be true. On the contrary, there is plenty of evidence and plenty of reason to believe that (1) the economic harms of global warming will hit developing countries and the poor especially hard, undermining and defeating all efforts to overcome global poverty, and indeed this is already happening; (2) developing countries and the poor lack the resources to deal with or adapt to the effects of global warming which will multiply the harm and the human suffering it will cause; (3) developing countries and the poor stand to economically benefit from a global effort to mitigate and reverse global warming through the development and application of energy efficiency, clean renewable energy and organic agriculture technologies.

    Moreover, since the harmful effects of anthropogenic global warming that we are experiencing now and will experience in the next several decades are overwhelmingly the result of fossil fuel use by the rich, industrialized world — in particular the USA — the rich nations of the world have a responsibility to help the developing world with any harmful economic impacts that mitigation may bring, as well as to fund technology transfer to the developing world so that the poor countries can bypass unsustainable and destructive fossil-fuel based development, have access to the technologies and tools to provide clean renewable energy needed for sustainable economic development.

    Steve Reynolds wrote: “For people who believe the economic effects of mitigation will be worse than the original problem (at least in short to medium term), aggressive mitigation is not in the interest of the poor.”

    There is no valid reason for anyone to believe that “the economic effects of mitigation will be worse than the original problem” for the developing world, or the poor, or the vast majority of human beings on this planet. The only reason I can think of that someone would “sincerely” believe this is that someone has heard it repeated over and over again by various propaganda outlets and has uncritically accepted it as fact and neglected to investigate the facts which show there is no basis for this belief.

    There is one group of human beings on this planet for whom the “the economic effects of mitigation will be worse than the original problem” and that is people who profit from the use of fossil fuels. A “business as usual” approach — with fossil fuel consumption increasing and accelerating until it eventually peaks and declines due to depletion of supplies — stands to bring trillions of dollars of profits to this group of human beings. They do not want that flow of profits to be “prematurely” ended because the world embarks on a program to rapidly phase out the use of fossil fuels and migrate to clean renewable energy sources, which is at the heart of any global warming mitigation agenda.

    Of course, most people are not going to shed tears over the prospect of Exxon-Mobil losing some of its multi-billion-dollar annual profits as income and wealth shift to manufacturers of wind turbines, photovoltaics, biofuel systems, etc, so rather than bring their case honestly to the public, the fossil fuel profiteers promote bogus talking points about how “the poor” will suffer from addressing global warming.

  26. 126
    J.S. McIntyre says:

    re 119

    Short, cynical answer: Because they consume less energy, and thus cut back on profits. If you question this, remember what Enron did to California at the very beginning of this century.

    This may sound extreme (but then, so is the long term outlook for the effects of climate change on the biosphere we depend upon for sustenance) but I’ve felt for a long time that regulations should have been put in place long ago that maintained all new single-family homes and rental properties should be constructed with an eye on passive energy-saving architectural principles, and that they should be mandated to have a “plug-‘n’-play” set-up for hooking up energy alternatives like solar and wind, leaving the owner with the option to install panels or windmills.

    The irony is readily apparent – if we had these things put in place even a decade ago, we’d be much further along with a response to AGW, and have the beginnings of an infrastructure in place to expand upon rapidly.

  27. 127
    Figen Mekik says:

    Carbonate rock refers to limestones (CaCO3) and dolomites (MgCO3); carbonaceous means mostly made of organic carbon, like coal or black shales.

  28. 128
    J.S. McIntyre says:

    Lawrence Brown.

    A short note of thanks for your recommendation made elsewhere of the Nov/Dec issue of The Bulletin of the Atomic Scientists. Very good read, expanding on something I read in Field Notes From a Catastrophe.

    There are several pieces in the mag re Climate Change worth reading; interesting, sobering reads that address some of the discussion brought up here. And the discussion with Bruce Smith regarding the viability of nuclear power as a response to climate change is very clear in showing why this is probably not a very good idea.

  29. 129
    Hank Roberts says:

    > carbonate, carbonaceous

    Yeah, without knowing Rod’s “some sources” it’s hard to figure out where the confusion is arising.

    Rod, in 88 you

    > re-ask a question. Some sources describe …

    What source?

  30. 130
    DanW says:

    Thank you for that clarification Figen Mekik.

  31. 131
    Mary C says:

    Re 81. Diane, take a deep breath. There are a number of good books out there on passive solar for heating; you might find it worthwhile to take a look. At you’ll find an interesting blurb about one of those books; the write-up gives a brief background on solar heating and passive cooling.

    You’re right that use of passive solar for heating in cold weather can be responsible for overheating in hot, but there are well-known and understood design principles that allow passive solar to work both efficiently and comfortably during cold seasons while preventing overheating in hot seasons. For example, I have a sun porch on my house that has windows on the east, west, and south. In spite of the fact that the porch is poorly insulated and distressingly leaky (yeah, I know, mea culpa), it stays fairly warm in all except the bitterest cold weather. When we bought the house, the porch would get hot, hot, hot and uncomfortable in the summer. A little effort with various means of shading has mostly solved that problem and I believe we can do more. You can see a very basic illustration of the difference in the way the sun strikes a house between winter and summer and what it means for passive solar at

    There are some great resources out there for using the sun for our energy needs: passive solar for heating through building design, solar collectors, solar hot water heating, and photovoltaics for electricity. If you can find an energy fair in your area, you can learn a lot about how all these things work and what is available right now. Some of the products are still prohibitively expensive in the short term, but I believe that situation is changing and will continue to do so. Of course, the question is whether it will happen as fast as we need it to or not, especially given the current lack of leadership and the committed efforts of vested intersts.

    As for temperatures getting warmer and doing away with cold winters–I don’t know that anyone is predicting tropical climates in the north in the near future. (Are they?) Where I live, at a little over 40 degrees latitude north, average monthly temperature from December through March ranges from a high of 39.4 degrees to a low of 26.1. Even if the atmosphere warmed up by 20 degrees in the next few years, I’d still need heat to keep my house livable during those months, although not as much as currently, of course. Still whatever amount of heat I need has to come from somewhere–better that it come from passive solar to the greatest extent possible than from continued use of fossil fuel. Better insulation and other conservation measures and better use of sustainable energy sources could make a big difference in how much CO2 we release into the atmosphere. No one effort is going to solve the problem, but, seriously, every little bit helps.

  32. 132
    Gareth says:

    Re: #119 (Lynn) and earlier comments re low energy housing…

    Try Googling “passivhaus”: a German design system for housing that uses no energy for heating or cooling. Passivhaus UK might be a good place to start…

  33. 133
    David B. Benson says:

    Here is a slightly different take on the main topic of this thread:

    which illustrates the necessity of immediate action with excellent graphics.

  34. 134
    John Mashey says:

    Re: solar houses and such now shows the results of the 2007 university competition to build good-looking & efficient solar-powered homes.

    The top 4 of 20, from around the world were:
    #1 Technische Universitat Darmstadt
    #2 U of Maryland
    #3 Santa Clara University
    #4 Penn State

    7 of the 20 teams got 100% on Energy Balance.
    This was a pretty serious evaluation.

  35. 135

    Re:#128, J.S.’s comments. I also found the articles in the latest issue of the “Bulletin” timely and important. Chris Mooney does a thorough job of exposing the foot dragging by the current administration, and the interview of Dr. Smith points up the enormous risks associated of using nuclear fission as an alternative energy source.

    James comment #84, shows that common sense has to go along with the use of improved technologies.What’s the point indeed of lighting up the sky at night? It gives cause to wonder whether, if we develop practical and affordable cars that get 80 miles per gallon, will drivers quadruple their mileage? This is why conservation is an important element, that ought to go hand in hand with improved efficiency.

    BTW David gaves a good primer on the factors that effect the PH of the oceans, on RC, a few years ago that’s pertinent to his introductory post.

  36. 136
    Steve Reynolds says:

    125 SecularAnimist> You offer no evidence to support the assertion that “the most severe economic effects” of mitigation will be to “developing nations”. In fact there is no such evidence and there is no reason to believe that this will be true.

    I have tried to point to such evidence (supported by 4 Nobel Prize winning economists), but apparently RC does not want you to see it; they censored my post.

    SecularAnimist> There is no valid reason for anyone to believe that “the economic effects of mitigation will be worse than the original problem” for the developing world, or the poor, or the vast majority of human beings on this planet. The only reason I can think of that someone would “sincerely” believe this is that someone has heard it repeated over and over again by various propaganda outlets and has uncritically accepted it as fact and neglected to investigate the facts which show there is no basis for this belief.

    The only reason that you can think of is incorrect. Please ask your question at the Fergus Brown site so I can answer without being censored.

  37. 137
    Rod B says:

    Hank, one of my sources of carbonaceous rocks:

  38. 138
    Joe Duck says:

    Mary C and SecularAnimist re: Mitigation Costs:

    My suggestion of a consensus among economists is based on my understanding of the work of Yale Economist Robert Mendohlson, a leader in this field who has extensively reviewed and published on this topic. I’ve emailed him for some clarification, but I think Steve Reynolds has this right.

    Secular a challenge in the way you address this above is that we all use fuels, and we could all cut that amount down. Almost everybody agrees that we should cut CO2 and GHG emissions, and everybody agrees we should not completely ban all energy use tomorrow.

    The question is this: What is the optimal balance with respect to mitigation? Almost all scenarios show that GDP will initially take a hit from massive mitigation – this is the large “cost” to the economy. The benefits depend a lot on how seriously climate change will hurt economies and also on assumptions about discount rates and such. Thanks to econ analyses we now know the folly of a pure Kyoto style approach (high cost, low benefits) and indicates why we need to look at the economics as we take steps to mitigate GHGs.

    Also – the risk to developing countries argument I (and Steve) make above is based partly on the inevitable GDP hit they’ll likely take during crucial development stages and also assumes that if we suboptimally allocate resources to AGW mitigation we will have less to devote to helping poor countries in other respects. This latter point is weaker than the GDP argument but it is better than begging the question about prioritizing taxes and funding for important things. Many would suggest that expensive mitigation has a lower ROI than poverty assistance.

  39. 139
    James says:

    Re #131: You should also note that solar heating doesn’t have to be passive. Passive solar generally needs to be designed in, as it’s an expensive remodel. Active solar collectors can be much less expensive, and can be retrofitted to most houses. Do a search on something like “solar space heating”.

  40. 140
    dhogaza says:

    I have tried to point to such evidence (supported by 4 Nobel Prize winning economists)

    Economists have a notoriously low track record in their ability to predict the costs of environmental regulations.

    I prefer science to ummm whatever economics is. Whatever it is, it is clearly not science.

  41. 141
    Hank Roberts says:

    OK, Rod, the source you gave includes the same answer Dave gave:
    “Carbonate – Silicate Cycle
    … Time scale for this cycle is millions to hundreds of millions of years, so not a major concern of humans… ”

    Accelerating that — mixing CO2-rich exhaust gas with ocean water and crushed limestone — has been proposed as a way of sequestering carbon in the ocean — giving the ocean a dose of calcium bicarbonate:
    Caldeira And Rau: Accelerating Carbonate Dissolution To Sequester Carbon Dioxide — Geophysical Research Letters, Vol. 27, NO. 2, Pages 225–228, January 15, 2000

    That was 7 years ago, I didn’t search for subsequent papers citing it to see what’s become of the idea; followups probably belong in the Geoengineering thread.

  42. 142
    mg says:

    140# dhogaza – yes, it is not clear that any of the so-called schools of economic theory (neoclassical, institutional, etc) address the matter of economic phase transition, which is the sort of thing that is being approached now. the challenge for economists is to present a framework that describes the mix of both first-order phase transitions and continuous phase transitions as the unsustainable emissions ‘bubble’ that is the current world economy and that has developed since the industrial revolution goes pop. it is difficult enough to describe and analyse phase transitions for physical systems; much harder therefore for a system whose signalling systems are ungrounded and whose structures have deliberately cut off so many of the earth’s feedback signals to it.

  43. 143
    Mike Donald says:

    #55 Hank Roberts Says:
    2 November 2007 at 2:43 PM
    Mike McDonald wrote:
    > And I bet you Christy never admitted the mistake ….
    Mike, you lost your bet.
    Before posting your belief, use the “Search” box at top of the page:

    Hank – thanks for the realclimate link which states that Christy+Spencer first introduced their error in 1998. Then Christy gave testimony, based on the erronous data, to the Senate in 2001. Then apparently the error was sorted out in the latter part of 2005. Are we saying that this uncorrected work was hanging about the web for – how many years? Seems like my bet was pretty safe for a certain amount of time.

    Has Christy gone back to the Senate and said “You know that stuff I said back in 2001…?” The realclimate link did say “it will be interesting to see if this is now corrected.”

  44. 144
    Roly Gross says:

    Re the John R Christy debate (#28), is this the same guy that has just co-authored a paper claiming that cirrus cloud cover decreases during tropical warming cycles?

    The science seemed interesting but I found the comment by one of the other authors rather suspect “Until we understand how precipitation systems change with warming, I don’t believe we can know how much of our current warming is manmade. Without that knowledge, we can’t predict future climate change with any degree of certainty.”

    And he also had a pop at climate modelling “Let’s see if climate models can get this part right before we rely on their long term projections.”

    Is this just more ‘cuckoo science’ or an interesting discovery?

  45. 145
    Fernando Magyar says:

    Re #138,
    On a somewhat lighter note:

    Two economists find themselves locked in a basement. They’re not sure what time it is, because it’s dark and they can’t read their watches. They think it’s nearly dinner time, cause they’re starting to feel hungry. But they’re not worried; they are not starting to panic – because they know that their demand will create sandwiches for them!

  46. 146
    Mike Donald says:

    It looks like the bet’s still on.

    I took your advice and did a bit of researching about Christy. He has his own little page on exxonsecrets and in the Guardian from this year (2007) I found:-,,2032361,00.html

    “The film (TGGWS) also maintains that manmade global warming is disproved by conflicting temperature data. Professor John Christy speaks about the discrepancy he discovered between temperatures at the Earth’s surface and temperatures in the troposphere (or lower atmosphere). But the programme fails to mention that in 2005 his data were proved wrong, by three papers in Science magazine.”

    It looks like Christy forgot to mention that too. I missed his condemnation of TGGWS as well. Or corrections to what he said in the film.

    I found the transcript of TGGWS at:-

    [[ Professor John Christy ] What we’ve found consistently, is that in a great part of the Planet, that the bulk of the atmosphere is not warming as much as we see at the surface, in this region. And that’s a real head-scratcher for us, because the theory is pretty straight forward. And the theory says that if the surface warms, the upper atmosphere should warm rapidly. The rise in temperature of that part of the atmosphere is not very dramatic at all, and really does not match the theory that climate models are expressing at this point.]

  47. 147
    Nick Barnes says:

    Steve Reynolds @136: I doubt very much that RC censored your post. They have been having intermittent problems with their software over recent months; comments often go missing without a trace. This happens to me about one comment in three.
    If they wanted to censor you, why would they allow you to post at all?

  48. 148

    Re #144: For Roy W. Spencer, see this:

    For the paper, it is in Geophysical Research Letters, i.e., legit. Let’s see how it holds up. It would be good to see a RC review of this.

  49. 149
    Lynn Vincentnathan says:

    RE mitigation costs, here’s a method that might help:

    1. First enact all purely money-saving measures, such as conservation (turning off lights not in use, cutting motor in drive-thrus, buying next house close to work, reusables, reduce); buying GreenMountain 100% wind-powered electricity, which saves a couple of bucks a month over conventional, dirty-powered electricty. And other such measures that purely save, with absolutely no up-front costs at all.

    2. Then once one has saved some $$ from that, plow that into low-cost, money-saving measures — CF bulbs, low-flow showerheads (which cost $6, but save $100 or more per year on water & energy to heat it), etc.

    3. Then once one has saved $$ on 1 & 2, then plow that into more expensive money-saving measures….maybe a SunFrost refrigerater, which really costs big, but also saves big.

    4. Then once one has saved big $$ on 1, 2, & 3, start plowing that saved money into things that pay for themselves, but do not go on to save more $$, AND into things that cost, but do not pay for themselves over time — like plug-in hybrid cars (which should be available by then).

    That way a person without a dime to spare (probably because of his/her energy/resource waste/inefficiency) can do it, which means everyone can do it. The rich can do it faster by investing their surplus, but even the poor can do it this way.

    Net loss: zero
    Net gain: life on earth

  50. 150
    Lynn Vincentnathan says:

    RE censorship on RC (#136), I’ve been censored in the past, but what I’ve found is if I tone down the rhetoric, make it polite and appealing to logic and reason, and make it more on-topic, it get accepted.

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