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Thin Soup and a Thin Story

Filed under: — david @ 2 May 2007 - (Türkçe) (Български)

A firm called is getting a lot of airplay for their bid to create a carbon offset product based on fertilizing the ocean. In certain parts of the ocean, surface waters already contain most of the ingredients for a plankton bloom; all they lack is trace amounts of iron. For each 1 atom of iron added in such a place, phytoplankton take up 50,000 atoms of carbon. What could be better?

Phytoplankton biomass does not last forever, any more than tree biomass does. The trick therefore is to get the carbon to sink out of the surface ocean into the depths, generally in the forms of snot and poop. Once it reaches a depth of a kilometer or so, it can decompose to CO2 again but the water will be isolated from the atmosphere for decades, maybe centuries.

There have been iron fertilization experiments of the ocean before, many of them, in the equatorial Pacific, the Southern Ocean, and the North Pacific. These are places where the ocean chemistry is right for iron fertilization, that is, where there is available nitrogen as nitrate or ammonia, and phosphorus. The experiments uniformly find that phytoplankton growth is stimulated by iron. But most studies have not found an increase in the rate of organic carbon sinking into deeper waters.

If could be, however, that a sustained fertilization will allow the snivelers and the poopers time to get their acts in gear and start exporting carbon more efficiently. This was the conclusion of a recent analysis of natural iron fertilization by the Kerguelen Plateau in the Southern Ocean (Blain et al, 2007). Previous iron fertilization experiments were generally single-pulse additions of iron dissolved in acid. The iron lasted a few days before sinking out on particles or mixing down. If iron were released into the ocean in the form of floating time-dissolving pellets, the steady stream of iron would probably be a more effective fertilizer than the single dumps were.

Once the CO2 concentration of the upper ocean is depleted by growth and sinking of phytoplankton, the timescale for gas exchange with the atmosphere is about a year for a one-hundred meter ocean mixed layer, typical of the tropics. Tropical surface waters, one could argue, will still be at the surface a year from now, so there is plenty of time for them to replenish their CO2 concentration by sucking it out of the atmosphere.

The problem with the tropics is that if tropical surface waters are destined to remain at the surface for a while, they are also probably destined to ultimately scrounge the iron they need, to use the available nitrogen and phosphorus. The water might duck into the thermocline for a few decades, but it will ultimately resurface and be subject again to photosynthetic plankton and iron fertilization from falling dust. Marinov et al (2006) showed that a stimulation of phytoplankton production in one part of the ocean usually acts to depress production elsewhere. So what’s the point of paying for a carbon offset to fertilize a water parcel now, when nature would fertilize it soon anyway? That’s against the rules of offsets; it has to be something that wouldn’t happen anyway.

The one part of the ocean where fertilization of the ocean does not depress the fertility elsewhere is the deep Southern Ocean. Here the water sinks to the abyss, rather than taking a leisurely tour through the upper ocean. But now the practical picture looks different. Instead of the benign tropics, you have sea ice, waters mixed to hundreds of meters down (bad for phytoplankton) and total darkness for much of the year. Fertilize that!

Modelers have long ago concluded that iron fertilization of the ocean can play only a small role in managing the carbon cycle in the coming century. Part of the issue is that the Southern Ocean also covers only a very small area of the surface ocean, just a few percent. Model experiments where the Southern Ocean is completely fertilized show a drawdown of maybe 15 ppm by the year 2100 [Zeebe and Archer, 2005]. We could change a light bulb and do better than that.

Perhaps however the total potential drawdown from ocean sequestration is the wrong question to ask. The total rate of biological export production in the ocean is probably of the order of 15 Gton C / year, and the fertilization enhancement could be at most maybe 1 Gton C / year. That can’t slay the 7 Gton C / year fossil fuel CO2 dragon all by itself, but could it help? Nowadays we’ve given up the idealistic search for a single solution, and we’re building the future out of wedges [Pacala and Socolow, 2004], or what the more dignified IPCC Working Group III calls a “portfolio of solutions”. Would carbon offsets by fertilizing the ocean be at least realistic?

The tropics I think would be fraud as a basis for carbon offsets because the fertilization would have happened anyway, eventually, naturally. I guess I could imagine the concept working as advertised in the deep Southern Ocean. Not so easy to fertilize down there, but if you manage to fertilize it, you will accomplish something that wouldn’t have happened anyway.

But the change in carbon chemistry of the ocean and ultimately the atmosphere need to be transparently documented, also, if we are to trade carbon offsets based on iron fertilization. Documenting a change in carbon content of surface waters might be possible in the tropics, but it would be a nightmare in the Southern Ocean, probably impossible to do reliably. Ocean chemistry data is generally cleaner than land data, less susceptible to local variability. In tranquil, well-behaved parts of the ocean like near the Galapagos, it would be probably easier to document changes in the carbon content of the upper ocean than it would be on land. On the other hand, the ocean moves around a lot more than the land does, in general. The Southern Ocean, in particular, is a maelstrom. Tracking a plume of fertilized water to measure the change in carbon content would be a mite trickier.

Southern Ocean surface water also has a harder time changing the CO2 concentration of the atmosphere, because it gets mixed into the interior so quickly. Ultimately it would take centuries to bring the atmospheric CO2 to a new equilibrium value. You would have to wait until your fertilized water filled up the entire deep ocean. I think the long time scale also means that a ton of carbon removed from Antarctic surface waters does not translate to a ton of carbon removed on some reasonable timescale from the atmosphere. The efficiency is much lower than that, and difficult to document.

I would put ocean fertilization on the avoid list, along with planting trees. It’s too hard to pin down the actual amount of CO2 removed from the atmosphere by your actions. It’s also not a long-term solution, since the ocean leaks. Humankind would have to keep fertilizing the ocean indefinitely in order to preserve the claimed CO2 drawdown. If you’re concerned about climate change, build a windmill. Ocean fertilization does not seem to me suitable to be the basis for a reliable financial commodity, or a practical tool for geo-engineering climate.

David Archer

Blain, S. Effect of natural iron fertilization on carbon sequestration in the Southern Ocean. Nature, doi:10.1038/nature05700, 2007.
Marinov, I. The Southern Ocean biogeochemical divide. Nature, doi:10.1038/nature04883, 2006.
Pacala, S. and S. Socolow, Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies. Science 305: 968-972, 2004.
Zeebe, R. and D. Archer, Feasibility of ocean fertilization and its impact on future atmospheric CO2 levels. Geophys. Res. Letters, doi:10.1029/2005GL022449, 2005.

137 Responses to “Thin Soup and a Thin Story”

  1. 51
    David B. Benson says:

    Re #52: Chuck Booth — Send the old trees to the landfill…

  2. 52
    richard ordway says:

    Re. #41 Sebb wrote: [On another tack to mitigation - does anyone have any insight or data on man-made albedo? The albedo of cities is higher already, what if we mandated white roofs?]

    I was at an NREL (National Renewable Energy Lab in Boulder, CO) briefing about nine years ago (~1996) and this idea (“painting all the Earth’s dark surfaces white”) was discussed then as part of an informal possible solution to combat AGW (human-climate change).

    (Yeah, they were up on the peer-science and were worried enough at that time to be thinking about this.)

    Some think tank people there, were suggesting it informally as just one part of a multi-pronged solution along with and part of several combined options…

    I believe they were running informal computer simulations of it using their own personal PCs, they stated.

    The possible solution came in five combined parts:

    1. Convert printing presses (“almost all on Earth) to make tiny mylar balloons, to reflect sunlight.

    2. Put space mesh into space with the space shuttle to reflect sunlight.

    3. Seed oceans with iron to increase CO2 “eating plankton”.

    4. Put fleets of aircraft into the high troposphere to run on “dirty” settings which emit aerosols which reflect sunlight.

    5. …and of course the “ole paint all the Earth’s dark surfaces white” idea.

    If I remember correctly, their initial calculations showed (in those days), that all these methods combined together might just be effective…

    …but they did tell me that they were worried of the possible “unintended” consequences.

  3. 53
    Steve K says:

    I’m dismayed to see so many people pouring out so much negativity, so prematurely. Look folks, here’s the reality: nobody really has enough data to make any judgements about any of this. To say “this can’t possibly work because the mathematical models say it can’t work” is just nonsensical. No serious field ecologist would take such a acomment seriously. The ONLY way to know anything about this process is to *try* it in situ and then *compare* it to your models.

    If the Planktos people want to risk their money going out and doing a 2-year study of this question, then by all means let them do it. Watch them carefully, make sure they are doing good science, and make them document everything with solid data. Make them prove it. But they should be encouraged, not discouraged.

    If their process can be made to work, then fine, the human race has been shown a very powerful new tool and can go through the long political and social decision-making process of deciding how much of it should be allowed. If it doesn’t work, then that’s the end of the idea.

    But above all, we must allow people to try new things. If we don’t have experimentation and novel work, then we’ll NEVER solve our climate problems.

    [Response:In principal I agree with you about attempting the impossible. But how can they ever document that they've changed the CO2 concenration of the atmosphere? I don't want to see people misled, and money misguided, by unverifiable claims of sequestering CO2 from the atmosphere. David]

  4. 54
    David B. Benson says:

    Re #51: Some comments seem to have been deleted, so the numbering is off by, currently, 2.

    Worse, I didn’t think through what happens to the old trees in the landfill: methane production. So that would have to be a deep landfill…

  5. 55
    Alvia Gaskill says:

    22: Pumping deepwater to simulate upwelling would be very energy costly. Another idea “floating around” is that of using thousand meter drain pipes vertically suspended in the ocean to take advantage of wave action that would in theory bring the upwelled nutrient laden water to the surface. This is in conjunction with a plan to entice small zooplankton known as salps to eat and produce waste pellets that would be more likely to settle to the bottom. This was discussed in the thread about the Branson prize a while back.

    32: In deleting my duplicate post on the iron vs. diatoms issue, both posts were deleted including the links to the articles. I will repeat this from memory as best I can.

    [Response:I apologize, I was trying to clean up and I screwed up. David]

    A 2004 study off the coast of Alaska found that not only was iron a limiting nutrient, but so was silica, since diatoms make up about half the phytoplankton and use the silica in their cell walls. Once the silica is used up, either more has to be added at a ratio of 5000:1 or the diatom population crashes and the phytoplanton population that survives is diatom depleted. My existing post says this could create an imbalance in the ocean ecology and cause problems of an unknown nature in the food chain. The Planktos representative mentioned that 2 supertankers of iron would be sufficient to do the job, but this would also require 10,000 supertankers of silica, a hard to manufacture chemical in the quantities required.

    Finally, a symposium at NAS this past week included a disturbing presentation from a zoologist from Oregon who said that changes in coastal wind patterns appear to be altering existing upwelling currents, creating excessive algal blooms that result in anoxic areas of thousands of square miles. Too much fertilizer not a good thing.

  6. 56
    Steve K says:


    Your response seems to me a perfect example of the problem…people prematurely judging things based on guesswork, instead of hard data. You are basically saying: “don’t even let them make the attempt”.

    You say, for example “But how can they ever document that they’ve changed the CO2 concenration of the atmosphere?”

    My response is: “I don’t know how they are going to document it. Maybe they will find a way that is convincing. Maybe they won’t. But we’ll never find out if they don’t try it, will we?”

    As to your concerns about money, again, if they are willing to use their own money and risk it to try this, then that looks like a net gain for science no matter what. If they fail, then we’ve learned something useful. If they succeed, then we’ve also learned something else useful.

    What I don’t understand is why so many people seem so determined to make pre-judgements about the scientific validity of this, and so many other proposed solutions.

    [Response:Maybe they will find a story that will convince people who don't know any better. But if there were a way to document real CO2 drawdown from the atmosphere in a way that would convince someone who is scientifically literate, say by a model calculation that showed significant CO2 drawdown, or by some new measurement technique or strategy, then they could describe that now, it wouldn't require new field work. Field work is not the issue. In the absense of some convincing refutation of model calculations that fertilizing the ocean will have minimal impact on atmospheric CO2, it is my obligation as a scientist who has studied and published on this problem to say that the emperor ain't wearing any clothes. David]

  7. 57
    Phil Scadden says:

    I would appreciate some pointers to papers on why CaCO3 precipitation would be bad thing. Shell carbonate is surely a long term sink for CO2 and I have colleagues in paleoclimate speculating that foraminifera precipitation may have been a major factor in the cooling through the Tertiary. Marine people here have also been wondering if closing fishing and especially trawling on areas with high shellfish productivity might earn CO2 credits.Ca++ is surely not the only buffering agent at work. Thanks

    [Response:CaCO3 is chemically a base. When it is removed from seawater, it tugs the reaction

    2 HCO3- < --> CO3-- + CO2 + H2O

    to the right, increasing the availability of CO2 to degas to the atmosphere. David]

  8. 58
    Alex Rau says:

    Yet another red flag among many on Planktos: look at the financial backers of the company. Planktos is financed by a company called Solar Energy Limited. The only other investment of Solar Energy Limited is in a company called D2Fusion, which is … a cold fusion commercialization company. This does not lend alot of credibility to their operations, scientifically or otherwise.

  9. 59
    ray ladbury says:

    I suspect this post will be controversial, so I’ll apologize in advance for any feathers ruffled. My intent is to spur discussion of mitigation, not offend.
    I think that climate change may well represent the gravest threat human civilization has faced (well, maybe except for human stupidity). I also believe that we are very close (decades away) from being unable to reverse the trend. I presume that most people who frequent this site share these sentiments to some extent. The question is what we are willing to do to counter that threat. If we are market-oriented capitalists, are we willing to accept more regulation? If we favor a more controlled economy, are we willing to accept that the market may provide part of the answer? If we oppose nuclear power for safety or anti-proliferation reasons, are we willing to at least look at the possibility that nuclear power can help meet rising energy demand and keep the economy healthy while lowering ghg emissions. Are we willing to try the occasional crazy idea (like fertilizing the oceans or painting the newly denuded south pole white in a couple hundred years)? Are we willing to put much of scientific endeavor on hold for a century while we deal with this threat?
    The reason I ask these questions is because skeptics and laymen who do not understand science will judge the seriousness of the situation in part by what we scientists are willing to do to counter the threat. Many of them do not share our sense of urgency. Many of them do not understand opposition to nuclear power, etc. To them an absolute refusal to consider nuclear power as an option is seen that concern over global warming does not rise above the fear of nuclear power. To them, unwillingness to embrace the occasional crazy idea may imply that the situation is not truly grave. When people do not judge risks on their merits, they tend to judge them comparatively.

  10. 60
    C. W. Magee says:

    Re David’s comments on verification:

    Verifying whether iron-seeded carbon is sequestered in the deep waters beneath seeding areas should be possible by looking at the change in 14C bomb-spike mixing rate in those areas.

    Surface water and atmospheric CO2 is enriched in 14C as a result of 20th century atmospheric thermonuclear weapons testing. As surface waters mix into the deep ocean, the 14C content gradually increases. Sinking climatologically significant amounts of surficial, 14C enriched CO2 should increase the 14C penetration rate into the deep ocean. If Planktos is serious about proving their sequestration, all they need to do is contract a 14C lab to test the ocean waters and sea floor detritus beneath their seeding areas, to compare modelled and observed 14C enrichments. We don’t need to be skeptical about their claims; in the words of a great cold warrior, we can trust, but verify.

    Does anyone know if they have made arrangements with any 14C labs to verify their seeding experiments? Has anyone asked?

    [Response:Interesting idea, but my impression is that the 14-C distribution of the subsurface waters of the ocean are only slightly impacted by sinking organic material. An easier, more sensitive, and totally analogous measurement would simply be dissolved oxygen or nutrients (nitrogen and phosphorus). Of course, the water column time-integrates the biological impacts on oxygen etc, so an even more direct measurement is the sinking flux of particles, measured in sediment traps. David]

  11. 61
    Greg Simpson says:


    That got me thinking (along with other, I see). Some quick calculations lead me to believe that a 200 km x 200 km bin, 100 m deep, filled with cut down trees, would sequester enough carbon to make a difference. If kept dry, they should last centuries (furniture does). Keep the bin filled with argon and that time period should be much longer. Of course, numerous smaller storage areas would be more practical.

    All this is useless while we keep burning coal and other fossil carbon in large amounts, but this technique could be used to draw down carbon dioxide levels more rapidly than would naturally occur after we cut our emissions to a sustainable level.

    There are probably better ways to achieve the same ends, but I don’t think we have to wait centuries for the natural balance of atmospheric gases to be restored if we’re willing to spend a lot of money to fix it.

    [Response:Farm waste could just be flushed down into the deep ocean, There could be some gigatons there, I once heard it said. David]

  12. 62
    Chuck Booth says:

    Re # 58 [a 200 km x 200 km bin, 100 m deep, filled with cut down trees, would sequester ...]

    Why not just ship them to outer space – it would probably be cheaper, and would not take up 40,000 sq km of the earth’s surface.

  13. 63
    Phil Scadden says:

    re: 56. So that reaction is implying that for every C02 removed from seawater by a CaC03 precipitate, another C02 is released to the atmosphere? But with the whole carbon cycle operating, isnt it still preferable to have the permanent C02 removal? Certainly longer term that absorption by trees.

    [Response:Permanent removal of carbon into sedimentary rocks in a natural world has to wait for weathering reactions of igneous rocks. The relevant reaction is

    CaSiO3 + CO2 < --> CaCO3 + SiO2]

    where CaSiO3 is a simple igneous rock, and CaCO3 and SiO2 are sedimentary rocks. This reaction takes hundreds of thousands of years to consume CO2. It would be done artificially, neutralizing fossil fuel CO2 captured from a smokestack. There is a paper Rau and Caldeira, Energy Conversion and Management 49 (1999) 1803-1813, 1999, about this idea. David]

  14. 64
    Tosh says:

    A few comments have picked up on the idea of ‘dead zones’ – basically anoxic (oxygen depleted) conditions. See

    as the link explains, algae blooms can deprive other organisms of essential oxygen in the water, creating widespread deaths of marine organisms.

    Sounds like planktos may have a few justifiably angry antagonists to any projects it tries to get off the ground. May planktos fail spectacularly. Lets get back to real solutions please.

  15. 65
    Lynn Vincentnathan says:

    Or we could turn off lights not in use, etc.

    I’m reminded of the TV movie (in the 1970s or 80s), THE DAY AFTER, re all-out nuclear war. After the movie they had panel of experts talking about what to do if all the nukes go off — civil defense, etc, subways as bombshelters, etc. Doctors, gov people, & engineers spoke. Triage, logistics…the works.

    There was this little old philosopher on the end of the dais. At last he spoke: “You don’t understand, we can’t let this happen in the first place.” My friend & I agreed that he was the only one who made sense.

  16. 66
    William Astley says:

    Re: Increased Biological Production in Current Near Lifeless Areas of Ocean to Remove CO2. Process active in the Past?

    The below article explains that increased biological production in the ocean, due to iron and phosphate in dust is hypothesized to have cause an increase in biological production in regions of the earth�s ocean which are currently almost lifeless due to a lack of nutrients. The increased biological production is the hypothesized reason why the CO2 levels during the glacial periods dropped from around 280 ppm to 180 ppm.

    Review article in Nature “Glacial/interglacial variations in atmospheric carbon dioxide” by Sigman and Boyle (2000)…man_nat_00.pdf

    The 100ppm drop in CO2 during the Glacial cycle is not primarily due to colder oceans. The following is an explanation of why colder oceans alone can not account for a 100 ppm drop in CO2. (Summary from the paper. See paper for details).

    As there is a vast amount of fresh water in the glacial period, in the new ice sheets, the ocean becomes Salter (3%). Salter water can hold less carbon dioxide (6.5 ppm less for a 3% increase in salt content). Colder water can hold more carbon dioxide, however, the deep ocean is already an average of 4C and will freeze (salty or not) at around -1.8C. The estimated maximum drop deep in deep ocean temperature is 2.5 C. The surface subtropical oceans were estimated to have cooled by about 5C. (Note vast areas of the high latitude oceans were covered by ice, during the coldest period and could hence no longer absorb carbon dioxide.)

    The reduction in carbon dioxide, due to colder oceans, is estimated to be max. 30 ppm. Now as vast areas of land which are currently forested, were covered by the glacial period ice sheets, the temperate forest is no longer using carbon dioxide which adds carbon dioxide to the atmosphere. In addition, during the glacial period large sections of tropical rain forest changes to savannah (About a third of the tropical forest changes to savannah. The planet is drier when it is colder), as savannah is less productive that tropical forests that change also adds carbon dioxide to the atmosphere. The Nature article estimates the temperate forest change and the increase in savannah, adds 15 ppm of carbon dioxide to the atmosphere.

    The net for this calculation is therefore = – 30 ppm + 6.5 ppm + 15 ppm = -8.5 ppm.

    As there is 100 ppm to explain the above are not the solution. The above article explains that increased biological production in the ocean, due to iron and phosphate in dust is hypothesized to cause an increase in the biological production in regions of the earth�s ocean which are currently almost lifeless due to a lack of nutrients.

  17. 67
    Hank Roberts says:

    >ship them into outer space
    Chuck, google “pound low earth orbit” for reality check.

  18. 68
    Timothy Chase says:

    Ray Ladbury (#58) wrote:

    The question is what we are willing to do to counter that threat. If we are market-oriented capitalists, are we willing to accept more regulation? If we favor a more controlled economy, are we willing to accept that the market may provide part of the answer? If we oppose nuclear power for safety or anti-proliferation reasons, are we willing to at least look at the possibility that nuclear power can help meet rising energy demand and keep the economy healthy while lowering ghg emissions. Are we willing to try the occasional crazy idea (like fertilizing the oceans or painting the newly denuded south pole white in a couple hundred years)?

    I hope no one minds if I get on my soapbox…

    I am a moderate conservative – not that far from what many would call a “liberatarian.” Ideals of 1776, that sort of thing. I have studied totalitarianism and totalitarian ideologies. I believed in maintaining a strong nuclear deterrent. I believe that few things are as efficient as a free market. And I would say yes to all of the above.

    The longer we wait, the more draconian the measures that will be necessary as conditions get much, much worse and as we will have fewer and fewer resources at our disposal, and will become more divided over what little is left. The more draconian the measures, the more likely that we will slip over the edge into some form of totalitarianism with no respect for individual liberty – and with no free market to fall back on. And one thing I know quite well is that totalitarianism is extremely inefficient, poor at science, and generally more concerned with the elimination of freedom of thought and of improving the lives of its citizens. If we descend into that, I believe there is little hope of our being able to respond to this crisis.

    If someone values individual liberty and freedom of thought, now is the time to act with urgency. If we wish to be able to respond to this crisis, we must do so now. For the sake of liberty, freedom and even humanity itself, we cannot let this wait. The window of opportunity is rapidly closing, and unless we act soon, in time, darkness will be all that we have left.

  19. 69
    Timothy Chase says:

    Regarding what not to cut back on…

    There is much science which I would not cut back on, whether it is in terms of the study of alternate forms of energy (or the study of photosynthesis which shows some promise of raising the efficiency of commercial photovoltaics from around 20% to the 95% that plants achieve) or molecular biology (which may offer alternatives to current industrial methods by harnassing the power of bacteria – and which may offer hardier plants with which to feed people) or climatology. I am not a climatologist. However, I realize that our models are becoming much more powerful, and climatology can give us the power of foresight in dealing with what lies ahead. In a certain sense, science is what got us into this mess, but it is also the only thing which can get us out.

  20. 70
    PHE says:

    We must be very careful with the concept of carbon offsetting. It must not be a substitute for reducing general air pollution and emissions (especially in urban environments), or for improving energy efficiency. However significant the impacts of climate change may be, general air pollution (which causes smogs, allergies, asthma, etc.) currently has greater impact on human health. It is too easy to spend a few extra dollars (as little as $20 or $40) to ‘offset’ an air flight, or annual car use, etc, and therefore satisfy your conscience that you are ‘doing your bit’. Reducing your carbon footprint can be a useful metric for reducing energy use and pollution, but is no solution on its own.

  21. 71
    Jacob Tanenbaum says:

    I am curious what the effects of fertilization would be on the PH of the surface layer of the ocean. Would this process drive the PH of the water down? If so, would it affect the ability of some sea creatures to form shells?

    [Response:No. Fossil fuel CO2 itself causes these problems, but fertilizing the ocean would if anything shift the pH back toward the basic, and stimulate CaCO3 production. David]

  22. 72
    Nick Gotts says:

    Re #59 “The question is what we are willing to do to counter that threat. If we are market-oriented capitalists, are we willing to accept more regulation? If we favor a more controlled economy, are we willing to accept that the market may provide part of the answer? If we oppose nuclear power for safety or anti-proliferation reasons, are we willing to at least look at the possibility that nuclear power can help meet rising energy demand and keep the economy healthy while lowering ghg emissions. Are we willing to try the occasional crazy idea (like fertilizing the oceans or painting the newly denuded south pole white in a couple hundred years)? Are we willing to put much of scientific endeavor on hold for a century while we deal with this threat?”

    I’d go along with most of that. Quibbles:
    (1) I’d say “market mechanisms” rather “the market” have a role – “the market” is an object of worship, perceived by its devotees as axiomatically virtuous and fair, and outside human control.
    (2) “rising energy demand” should not be considered a given – I’d add to Ray’s list “If we are pro-nuclear power, or pro solar/wind/whatever, are we prepared at least to consider that there may be no way we can go on increasing energy use without unacceptable environmental costs?”

  23. 73

    [[Why don't we just use atmospheric water generators (essentialy very large dehumidifiers) to suck some of the water vapor out of the atmostphere.. You know, the same water vapor that is responsible for 90% or so of the actual Greenhouse effect. ]]

    Wouldn’t work. The amount of water vapor in the air is controlled by the ambient temperature and the relative humidity. The missing water vapor would be replaced by evaporation from the oceans in less than a month. BTW, water vapor provides about 66% of the clear-sky greenhouse effect, not 90%.

  24. 74

    [[what if we mandated white roofs?]]

    Urban areas are only 1-2% of land space to begin with, so the effect would be minimal. Might help with air conditioning costs locally, though.

  25. 75

    [[Re # 58 [a 200 km x 200 km bin, 100 m deep, filled with cut down trees, would sequester ...]
    Why not just ship them to outer space – it would probably be cheaper, and would not take up 40,000 sq km of the earth’s surface.

    Wait a minute… why don’t we build wooden satellites and spaceships? Yeah! Of course, re-entry might be a problem… but we could coat them with ablatives… and of course, gas could get through the wood, so there’d be a leakage problem… but we could paint the wood… And wooden spacecraft would be lighter, thus requiring less fuel to lift off. I meant this sarcastically but now I’m beginning to wonder. Of course, it couldn’t easily be done on a scale large enough to affect GW.

  26. 76
    Ray Ladbury says:

    Nick, First, given that over half of humanity uses very little and that they are bound to demand rising standards of living, I see no way that energy demand will fall this century. First, consider China: The government knows that its continued existence is jeopardized unless the Chinese economy grows at 8% per year for the next 25 years of so–that’s just to keep unemployment were it is. India is even more dependent on economic growth. Neither economy is at a stage where economic growth can be severed from energy demand growth. Brazil does not have the same population pressures, but it’s economy is fragile. African countries have not even reached take-off yet. My question is this: How do we keep people in these regions from burning coal or firewood or charcoal if it is the only means they have of putting food on the table? Could demand be cut back in the US, Europe, Japan and Korea. Probably. However, people will never vote themselves out of a job. Moreover, combatting climate change will not be cheap–it will take a healthy global economy just to pay for mitigations.

    As to markets, there is nothing magical about them. They work for the same reason scientific consensus does–they de-emphasize and even punish extreme or wildly incorrect views and they reward being right. Yes, they can be manipulated, but they eventually punish the manipulations, too (dot-com and housing bubbles come to mind). The problem with markets is that they tend to focus near term (5 years or less, unless you’re Warren Buffett) and they don’t work if people don’t at least understand the risks. It is, however usually much easier to manipulate a government than it is to manipulate a market. That is why lobbying firms have offices on K Street rather than Wall Street.

  27. 77
    Chris Shaw says:

    Didn’t this principle work on a truly massive scale for billions of years during the Precambrian?

    The limestone and dolomite deposits and iron oxide sandstones from the precambrian are massive. There was a lot of iron in the early oceans that took billions of years to get rid of.

    All that oxygen in our atmosphere today came from biological processes which must have been much more productive in the ancient past.

  28. 78
    Sebb says:

    I was at an NREL (National Renewable Energy Lab in Boulder, CO) briefing about nine years ago (~1996) and this idea (“painting all the Earth’s dark surfaces white”) was discussed then as part of an informal possible solution to combat AGW (human-climate change).

    Maybe it would take “all the earth’s painting capacity” to paint the earth’s dark surfaces white overnight, but the first question is how quickly you want to make the change. If you have forever any painting capacity will do. We paint 65 million cars every year as it is – what if they were all painted white? You would still have to net out the reflectivity of a car painted another color, but I’m using very rough estimates of the percentage that are already white, the percentage that are replacing junked white cars, and the percentage that are left in the sun during the day. Maybe a net increase of 50 million square meters of bright white each year with no net ‘unintended consequences’. OK, that IS less than .003% of the area of September arctic sea ice lost since 2001, compared to the average of the 1979-2001 period – a white to dark change that’s going the wrong way. Then assuming a 10 year car-life (no increase in white junking) a decade of this would produce 0.03% of the sea ice lost….not impressive, but may be more effective nearer the equator…..up to 0.05%….still looks pretty insignificant.

    Meanwhile there must be some standard positive (or negative) cooling calculation that is done in the models for ground level albedo – I wonder what it is for white paint versus black car paint? And what the ounces of CO2 equivalent per sq ft per year is? Be interesting to compare car roofs, house roofs, concrete (OK, very energy intensive, I know) versus blacktop etc etc for such casual calculations….

    More importantly : the A/C impact of white roofs on houses – one estimate I saw of cooling via evaporation of spray on a black rubber roof I think was high (thousands of killowatt hours in a year), but did reduce a significant percentage of the household energy consumption. That evaporation technique could be replaced with a white rubber roof (was a flat roof) for significant reduction in home energy consumption in hot affluent A/C-using climates.


  29. 79
    Timothy Chase says:

    Ray Ladbury (#76) wrote:

    As to markets, there is nothing magical about them. They work for the same reason scientific consensus does–they de-emphasize and even punish extreme or wildly incorrect views and they reward being right. Yes, they can be manipulated, but they eventually punish the manipulations, too (dot-com and housing bubbles come to mind). The problem with markets is that they tend to focus near term (5 years or less, unless you’re Warren Buffett) and they don’t work if people don’t at least understand the risks. It is, however usually much easier to manipulate a government than it is to manipulate a market. That is why lobbying firms have offices on K Street rather than Wall Street.

    I am in large agreement with this assessment.

    However, in defense of markets, I would say that to the extent that they have been permitted to act, as a result of their decentralization which is capable of coordinating economic activity on a level and efficiency that greatly dwarfs anything a centralized economy would ever be capable of, they have demonstrated an almost magical ability to expand the range of economic activity, raising living standards over time, increasing the capacity of our civilization to support more people, and thereby increase the atmospheric level of greenhouse gases at a rate… well, I suppose there are drawbacks.

  30. 80
    Larry says:

    Two thoughts for you today.

    Our GHG problem is short-term, but most changes that claim to be solutions are long-term. As today’s IPCC report makes clear, there are many things we can do, but I remain unconvinced that doing them will result in much beyond delaying CC by a handful of years. If that’s true, and even if you accept the 3% of world GDP cost figure they marshal, moderate delay doesn’t seem worth the expense, especially if you’re a developing nation, for whom every iota of GDP growth is more than precious. To truly stop CC, we have to get GHG back to 1890 levels, not 1990 levels.

    RE planktos. They may be crazy, but there is a larger, longer-term idea here. It is that unlike the land, the oceans remain hunting grounds (using nets rather than bullets.) Eventually, and probably this century, we will treat them as agricultural areas. That is, we will apply human ingenuity and technology to increasing their productivity radically, as we have learned to do on land. Iron seeding and today’s fish-farming seem like the equivalent of the early days of agriculture, before the green revolution, no-till, etc. We may hope that sustainability and large-scale carbon capture are part of this new picture.

  31. 81
    FishOutofWater says:

    Good point, David, but the ocean is oxidizing, so that when plankton dies the carbon oxidizes back to CO2, closing the cycle, leaving no net change. Generally, in the open ocean where fertilization would increase productivity, carbon is not removed by sedimentation.

    There are good reasons why models show that fertilization is ineffective.

  32. 82
    Chuck Booth says:

    Re # 67
    Surely you’re not suggesting that loading millions of trees on to rocket ships and sending them to deep space is any less feasible than storing those trees in a 4000 cubic km grave (maybe several of them?) until the threat of global warming has passed?

    I think Barton P.L. (#75) spotted my tongue planted firmly in my cheek.

  33. 83
    Hank Roberts says:

    Sinking wood below the depth where oxygen is available is indeed a way of preserving it for a very long period.

    The Black Sea, the deep Mediterranean, and the deep ocean in places all could serve as such a repository. Even places in the Great Lakes are sources of well preserved wood from a century ago, from ships that sank with loads of big trees. You can look this up.
    One example of many:
    … shipwrecks are better preserved in the anoxic layer than in the oxic …
    1991 The oxidation of H. 2. S in Black Sea waters. Deep-Sea Research 38(Suppl. …

    The “ocean” isn’t all the same, isn’t “oxidizing” — there are organisms eating plankton in the shallow layers, dead or alive —- the deep ocean sediments show the steady accumulation of plankton calcite/aragonite and silica shells over time.

    Look at any of the sediment core papers published, look for photographs. The idea of boosting plankton may not make sense for a variety of reasons, but stay with the facts in this argument, please. Chasing wild theories that lead to statements with no basis in the field work is just recreational typing.

  34. 84
    Timothy Chase says:

    Carbon Sequestration and the Kitchen Sink…

    I ran across a different approach to carbon sequestration – something which shows the potential for locking carbon in the soil and enriching it for thousands of years, reducing deforestation, reducing forcing by nitrous oxide, and which appears to be economical. Or in otherwords, it sounds a little too good to be true. I think it might be nevertheless….

    Birth of a New Wedge
    By Kelpie Wilson
    Thursday 03 May 2007

    International Agrichar Initiative 2007 Conference
    April 29 – May 2, 2007
    Terrigal, New South Wales, Australia

    Hoperfully a few of our mates from down under will be able to share with us a few of the details they might come across…

  35. 85
    James says:

    Re #82: [... less feasible than storing those trees in a 4000 cubic km grave (maybe several of them?) until the threat of global warming has passed?]

    I don’t see that tree storage is all that infeasible: after all, it’s been done, hasn’t it? Seems like a simple one-line description of coal formation to me :-)

    But of course there’d be a certain circular futility in such a plan: while one set of humans are digging up the millions of years old buried trees and burning them, another set are busily burying new trees to remove the CO2 that the first group created.

    [Response:I've heard the idea (from Gregory Benford at a meeting) that fossil fuel burns at a higher temperature than biomass does, hence by the steam-engine laws of thermodynamics the energy can be extracted more efficiently. An argument to burn fossil fuel and sequester biomass. David]

  36. 86
    FurryCatHerder says:

    [[Re # 58 [a 200 km x 200 km bin, 100 m deep, filled with cut down trees, would sequester ...]
    Why not just ship them to outer space – it would probably be cheaper, and would not take up 40,000 sq km of the earth’s surface. ]]

    Wait a minute… why don’t we build wooden satellites and spaceships?

    Okay, I know some people are getting a bit … weird … with their science, but before anyone runs off and makes a 200km x 200km forest dumping site, a 75 mile by 75 mile (120km by 120km, for those of you using new money …) PV farm would replace all of our current electric supply.

    Math –

    180w per square meter
    3.717 trillion kilowatt hours per year
    4 hours per day average insolation
    365 days per average year

    (mumble mumble mumble)

    3.717×10^15 WH/yr / 180W/m^2 / (365 * 4)H/yr = 1.414×10^10 m^2

    (some PV company is going to be RICH!)

    1.414×10^10 square meters = 1.189×10^5 meters square = 118km square.

    Looking at gigawatt nukes instead yields

    3.717×10^15 WH/yr / (1×10^9 W/H * 365 d/yr * 24 H/d * 70% uptime) = 606 nukes

    With 10×10^6 km^2 area, that’s one nuke for every 16,500 km^2. In old money, that’s one new GW nuke every 80 miles, north by south, east by west.


    A far more practical solution is to quit wasting so much of the stuff.

  37. 87
    FurryCatHerder says:

    [Response:I've heard the idea (from Gregory Benford at a meeting) that fossil fuel burns at a higher temperature than biomass does, hence by the steam-engine laws of thermodynamics the energy can be extracted more efficiently. An argument to burn fossil fuel and sequester biomass. David]

    Two words: Thermal depolymerization.

    Once we identify a sufficient waste stream of “available biomass”, we start recycling it using thermal depolymerization. Whatever’s leftover, we sequester. Trees, tires, sea critter shells, whatever.

    The end result is renewable energy from now until forever, with a gradual decline in atmospheric CO2. We get to have our cake and eat it, too.

    The output is light crude, natural gas, solid carbon and trace minerals. Cost per barrel is competitive with what’s coming out of the ground today and the feedstock is anything with long chain carbons. The technology is very straightforward and the outputs can be utilized tomorrow by existing fossil fuel infrastructure.

  38. 88
    david kubiak says:

    Belated response dump

    Regarding charges I’ve been concealing my Planktos affiliation: anyone who has put a cursor over my name on this blog might guess such sly deception was not the first thing on my mind.

    Regarding David’s comment inserted in my first post on the collapse of plankton and primary production in the Pacific, i.e., “changes in dust deposition are not the primary culprit.”, would just ask that he read the excerpts from the reports cited, e.g., NASA: “Reductions in NPP in the South Pacific were associated with a 35 percent decline in atmospheric iron deposition” and BBC/Nature: “The amount of carbon absorbed by plant plankton in large segments of the Pacific Ocean is much less than previously estimated, researchers say. US scientists said the tiny ocean plants were absorbing up to two billion tonnes less CO2 because their growth was being limited by a lack of iron.” There are of course other factors in play but a lot of scientists obviously see a major role for iron deficiency.

    Regarding the iron source: we’re primarily depending upon natural hematite deposits which if you google the word you will see are available everywhere. We are even reaching out to a French company that has developed a process that removes the tons of it that accumulate (like inorganic cholesterol) inside the pipes of public water systems. Since the only processing is essentially running the material through a modern version of a ball mill, very little energy is used in its preparation. Transport is the primary emission producing factor and in total each ton of hematite delivered should entail something like 10~ 20 tons of CO2 emissions. Once distributed in iron-depleted pelagic waters, each iron molecule can fix approximately 100,000 molecules of C in plankton biomass. (The enduring authority on these ratios is “Iron uptake and growth limitation in oceanic and coastal phytoplankton. Sunda W.G., Huntsman S.A., 1995. Marine Chemistry 50, 189-206 which reports Fe:C uptake ratios of 1:40,000 to 1:400,000 with a 1:119,000 average). We expect approximately 20% of this to sink below 500 m where it will be isolated from the atmosphere for centuries, which means that by weight each ton of iron replenished will sequester approximately 20~25 thousand tons of CO2 or roughly a thousand times more than the iron preparation/delivery generate. The other 80% of the carbon biomass is contributed as a free soup kitchen to the local surface critters and fisheries, so most will eventually get respired and end back up in the atmosphere.

    Regarding Chuck Booth’s question about oxygen production: There is actually still a surprising range of opinion in the scientific literature on this ranging from the numbers you cite to those quoted by CIESN below. Most of the numbers we hear range from 50 to 70% and we just thought it prudent to average them.

    Health and climate change: Marine ecosystems. Epstein, P. R., T. E. Ford, and R. R. Colwell. 1993. The Lancet 342: 1216-19.
    Center for International Earth Science Information Network (CIESIN)
    Plankton interact with climate by taking in CO2, by absorbing and scattering solar heat, and by emitting dimethylsulphide that seeds clouds, which cool the earth’s surface through precipitation and sunlight reflection. These biotic feedbacks help to modulate the earth’s temperature, the salinity of its oceans, and the composition of its atmosphere.
    By harnessing photosynthetically active radiation marine microflora produce twice as much carbohydrate (60 billion tonnes annually) as terrestrial plants. Phytoplankton produce 70% of atmospheric oxygen, that in turn generates protective ozone in the stratosphere.

    Regarding Alan’s skepticism about the krill collapse: Please see this Science Daily report on a paper from Current Biology:

    “Numbers of Antarctic krill have dropped by about 80% since the 1970′s. The most likely explanation is a dramatic decline in winter sea-ice. Krill feed on the algae found under the surface of the sea-ice, which acts as a kind of ‘nursery’… It is not fully understood how the loss of sea-ice there is connected to the warming, but could be behind the decline in krill.”

    Ditto from the British Antarctic Survey annual report: “A BAS -led team has pooled krill abundance data and shown that krill have declined by 80% in the last 30 years… Krill are a pivotal species in the Antarctic ecosystem and this shift in the food web is already affecting higher predators that depend on them as a food source. BAS scientists have also quantified how the growth of krill is related to the amount of food available in the water (chlorophyll concentration) and water temperature.”

    Regarding Jenn’s question about toxic responses: As far as we can judge from the lit we’ve seen on pelagic plankton, lethal blooms have rarely been reported. Nitrogen-fixing phytoplankton like trichodesmium do secrete some nasty molecules like monarch butterflies to discourage predators, but the ammonium they generate also nourishes many other plankton species so the overall biological effect is quite positive. Darwin even remarks on the effect in his Beagle voyage journal: “The line where the red [trichodesmium bloom] and blue water joined was distinctly defined. The weather for some days previously had been calm, and the ocean abounded, to an unusual degree, with living creatures.”

    In any case, the two main types of harmful algal blooms (HAB) that humans are familiar with are largely coastal shelf phenomena, like the red/brown tides of cyanobacteria, microflagellates, and dinoflagellates which secrete neurotoxins that can seriously disable or kill mammals (including us); and the river mouth “dead zone” blooms that are caused by industrial pollution and agro-chemical run-off. These deadly eutrophic blooms are sort of like the Al Qaeda of the plankton world, a nasty micro-minority that we ourselves artificially created with really stupid shortsighted policies, yet whose lethal activities give a bad name to all their benign productive brethren around the world.

    So considering this and the fact that none of the previous 10 international ocean iron seeding trials reported any toxic effects at all, we are not expecting any harmful reactions whatever in the open ocean. Nevertheless, we will be seeding these pilot blooms far out to sea in areas where they cannot drift to land, tracking speciation throughout their evolution, and monitoring all their biological effects. And since each of our six projected blooms will only be 2~3% the size of most wind-seeded pelagic blooms (and less than 0.003% of the ocean surface), and last 4~6 months at best, we are talking about very limited pilot project scale events.

    Regarding doubts about CO2 drawdown and potential efficacy: would just ask readers to consider two facts:
    a) Early experimental trials did report dramatic drawdowns. Just consider this one report from the National Science Foundation regarding one small attempt:

    Iron ‘Fertilization’ Causes Plankton Bloom
    Scientists link iron to climate change
    National Science Foundation
    October 9, 1996

    New results by National Science Foundation (NSF)-funded researchers, published in this week’s science journal Nature, confirm earlier experiments that indicated a strong biological response to added iron. But this time the effects lasted longer, and large changes were observed in the air-sea transfer of gases involved in climate processes.
    On an oceanographic research cruise called “IronEx II,” led by scientists from Moss Landing Marine Laboratories (MLML) in California, 37 scientists from 13 institutions in the U.S., England, and Mexico “fertilized” with iron a patch of ocean waters some 800 miles west of the Galapagos Islands. Nearly one-half of one ton of iron was added to the experimental patch, increasing surface water iron concentrations by 100 parts per trillion. The experiment was tracked for 18 days.

    Iron-starved plant plankton, called phytoplankton, native to the region responded rapidly; the amount of plankton began to nearly double each day. Working around the clock, scientists performed continuous measurements and over-the-side sampling operations. “Within one week, about two million pounds of phytoplankton had grown, representing a thirty-fold increase,” says scientist Kenneth Coale of MLML. “At the same time, the rapid growth of these plankton began to ‘draw down’ carbon dioxide in surface waters. After 10 days, the concentration of carbon dioxide had dropped 20 percent over the initial values.”

    The waters in which this experiment were conducted are representative of about 20 percent of the ocean’s surface area. They are called High Nitrate, Low Chlorophyll (HNLC) waters. “The experiment strongly supports the hypothesis that these waters do not grow more plant plankton because they lack iron,” says Don Rice, director of NSF’s chemical oceanography program, which funded the research along with the Office of Naval Research. Tiny additions of this nutrient to HNLC waters have the potential to cause rapid plant growth and a “draw-down” in the concentration of atmospheric carbon dioxide. This experiment may have pulled more than 2,500 tons of carbon dioxide from area waters before the patch was broken up by ocean currents, according to Coale. “It demonstrates that changes in iron supply to HNLC ocean regions play an important role in regulating atmospheric carbon dioxide and climate.”

    The tiny size of the bloom led to quick dispersal leading later teams to experiment with up to 8 tons of iron so the blooms would not be destroyed by wave diffusion or quickly grazed to death. The critical point about all these trials and data sets is that none of them were long enough to record the really productive stages of the blooms. Natural blooms last 4~6 months with most of the productivity (and carbon export) occurring during the mid-point of the bloom.

    Click here for an explanatory graphic of normal bloom duration vs. bloom experiments to date

    As the graphic shows the average experiment only lasted 22 days and the longest SOFeX experiment only lasted 50. And according to the NASA report on the two SOFeX sites,

    “SOFeX-S: Due to the high concentration of silicic acid and sufficient iron, this bloom kept on blooming and blooming — it was still “healthy” when the research vessel monitoring it had to return to port. As the diatoms were still healthy, not many of them died and sank to deeper waters, to the carbon flux exported from the bloom (measured by instrumented traps deployed beneath the bloom) was underestimated…

    “SoFeX-N produced a bloom that was somewhat more unusual. Rather than being composed primarily of diatoms, this bloom was a mixture of about 50% diatoms and 50% phytoplankton that did not make shells out of silica… Another significant result was that this bloom also showed no signs of slowing down when the experiment was over when ships had left the sites of the blooms.”

    In other words, all the modeling and speculation based upon the data at hand is likely discouraging for a simple reason – the ocean scientists did not have enough funds (ship time is expensive!) to stick around. The incredible results of the Kerguelen bloom study just published and cited above, that show results “one or two orders of magnitude” larger than the iron seeded blooms are being spun to suggest that only Mother Nature can accomplish this feat. What is misleadingly downplayed is that they measured the bloom and sequestration effect for a full three months or more than 4 times longer than the average iron seeded bloom. Look at the bloom duration chart again and I think you will see what is going on…

    In closing, would just like to say that people are perfectly entitled to oppose this work ideologically, but that should be a separate conversation from the scientific discussion, and in this field especially they are getting dangerously mixed up.

    Even the very positive results recounted in the NSF report above are spun in a final comment that states “Calculations for the equatorial Pacific, reported in the Nature papers, indicate that iron fertilization there would not significantly counteract the projected future increase of atmospheric carbon dioxide.” First no one has suggested the equatorial Pacific was the only or even best site for this work, but more importantly it turns out they used a catastrophic CO2 “projection” of over 700 ppm (vs. 380 ppm today) to make sure the effect looked hopeless in the extreme.

    One of the most infuriating aspects of this “debate” (not here gratefully, but plentifully elsewhere) are the charges that Planktos is pretending that this work will “solve global warming” or conversely that since it obviously won’t, it shouldn’t be tried at all. We obviously think this is one important piece of the answer and if workers in this field heed the Precautionary Principle and stop cold at restoration levels, we believe plankton power can safely play a significant climatic role – a primus inter pares role, if you will, among the other “wedges” promoted by Gore and the Princeton Carbon Mitigation Initiative. We still need unprecedented (and as yet politically unimaginable) source reductions, but while those wars are going on, we feel this ocean work is still a critical mission, too. I don’t know what it will take to get people to care about the accelerating loss of ocean life, but condemnation of attempts like this to slow or reverse it just because they are funded by offsets just seems the triumph of ideology over commonsense. And when ideologues contaminate science, it leads to disastrous environmental policy. After 6 years of this government that should now be pretty damn clear.

    Finally, just noticed that is now on record in the blogosphere as uniformly opposing this work.

    Polluting to save the planet: RealClimate disapproves
    Posted by Gar Lipow at 10:17 AM on 04 May 2007
    RealClimate, a blog run by leading climate scientists, thinks Planktos’s scheme to dump iron particles in the ocean to make plankton bloom and sequester carbon is “thin soup.”

    Now I can see that Dr. Archer is not favorably disposed, but given the rather reasonable discussion going on here, was just wondering if among the other “leading climate scientists” the disapproval was as seamless as Mr. Lipow shouts…?

  39. 89
    James says:

    Re #85 Response: [I've heard the idea (from Gregory Benford at a meeting) that fossil fuel burns at a higher temperature than biomass does, hence by the steam-engine laws of thermodynamics the energy can be extracted more efficiently. An argument to burn fossil fuel and sequester biomass.]

    I’d need to see the math on that. I suspect it leaves out the energy costs of coal mining & transport, and biomass burial.

    In any case, it seems that it’d be a marginal net benefit at best. Far more effective to leave the coal in the ground, sequester some biomass, and burn uranium :-)

  40. 90
    Chuck Booth says:

    Re # 88 There is actually still a surprising range of opinion in the scientific literature on this [global oxygen production by marine phytoplankton]

    I have no idea where Epstein et al got their figure of 70% – they don’t cite any reference – and I have certainly never seen any published values near that level. All of the papers I have seen (and I keep an eye out for this very estimate) put the number below 50%. In trying to promote a plan to use phytoplankton to remove CO2 from the atmosphere, I think it would be prudent to be conservative, rather than unreasonably optimistic, about the rate of marine phytoplankton primary production.

    If it turns out that the marine phytoplankton really do produce 60%, or 70%, of atmosphere’s oxygen each year, I would argue that makes a stronger case to not screw around with it – it is too essential to our existence on the planet. In other words, if it ain’t broke, don’t fix it.

    [Response:When phytoplankton or trees photosynthesize, they produce oxygen. But when they are ultimately respired, the oxygen is reconsumed. Almost all of the photosynthesis on land or in the ocean is balanced by respiration, so it makes little difference to atmospheric O2 what the balance of photosynthesis is between the land and the ocean. In order to leave behind O2, the organic carbon has to be buried someplace. Most burial happens in the ocean. Another fact to consider about atmospheric oxygen is that it has a lifetime, and therefore a response time to some perturbation, of several million years. David]

  41. 91
    Chuck Booth says:

    Re # 88 I find it curious that david kubiak wants the focus to stay on the science, rather than emotional responses, but when the researchers who conducted the fertilization experiment he cites cautioned against interpreting the results as a possible cure for global warming (perhaps because that study doesn’t offer a mechanism for sequestering the new phytoplankton biomass in the deep ocean?), kubiak dismisses this caveat as “spin.” Likewise, he dismisses Gar’s scientifically-based criticism of Planktos’s plan as “shouting.”

    Re: David Archer’s comments on my post (#90).

    I raised the point about the relative importance of phytoplankton oxygen production because david kubiak cited what seems to me to be an unrealistically high value, presumably because he feels it strengthens is his argument that highly productive phytoplankton are the key to CO2 remediation. I’ll be quite honest: I’m against large-scale geoengineering projects of this sort. Is this an emotional, knee-jerk response? Perhaps, but not entirely – it is also a result of having read about scientific experiments having unintended consequences (e.g., introduction of the cane toad in Australia to kill the beetles destroying sugar cane; or failing to appreciate how complex ecosystem processes really are (all too common in biomanipulation field studies).
    Even if ocean fertilization turns out to be a feasible (from an engineering standpoint) mechanism to reduce atmospheric CO2 (i.e., there is an easy way to transport the plankton biomass to the deep sea), I would be very concerned about unanticipated consequences to nutrient cycles and food chains in the surface waters of the ocean.

  42. 92
    david kubiak says:

    Breath-taking issues:

    Regarding Mr. Booth’s oxygen questions: I tried to point out that there is still obviously a controversy around these numbers but that crediting the plankton with 60% is not an unrealistically high value. If, as he says, he does keep an eye out for this estimate, may I direct it to the following recent statements:

    Perhaps not the most erudite source, but here’s Channel’s Joel Block responding to one listener in November, 2005: “Scientists believe that phytoplankton contribute between 50 to 85 percent of the oxygen in Earth’s atmosphere. They aren’t sure because it’s a tough thing to calculate. In the lab, scientists can determine how much oxygen is produced by a single phytoplankton cell. The hard part is figuring out the total number of these microscopic plants throughout Earth’s oceans.”

    More respectable perchance is Ali Khounsary, Ph.D. from the gov’s Argonne National Laboratory writing on an ANL webpage entitled World Oxygen Sources: “It is true that most of the earth’s oxygen production, PERHAPS as much as 90%, is from the sea plants through photosynthesis within the top 100 m of the ocean water where there is enough sunlight for the process to take place ”

    Or this from NASA: “It is estimated that phytoplankton, the plant forms of plankton, photosynthesize more than all other land and marine plants combined; some scientists place the figure at 90% of all photosynthesis on Earth. This means they also produce most of the oxygen breathed by humans and other animals.”

    And less breathily from a 2005 NASA report entitled: “The Mathematical Ocean: Deriving Planetary Health from Tiny Ocean Plants” – “There are many trillions of phytoplankton in the sea, and together they convert huge quantities of carbon dioxide (CO2) into living matter. In that process they release a major percentage of the world’s oxygen into the atmosphere.”

    And yes, there are other sources that say 45~50%, but between 90% and 45%, it doesn’t seem like a 60% average is over-reaching or spinning to “strengthen my argument”. Indeed, I too really am curious about the obvious imprecision in this rather vital statistic and wonder what the hell is going on. Sincerely, if you can find an unimpeachable source or consensus on this estimate, I would truly like to know.

    But whichever estimate is correct, the point is that we – collectively as a “civilization” – already have screwed around with this life-sustaining ecosystem – as Dr. Behrenfeld’s 12/06 Nature announcement of a 50% plankton die-off in the central Pacific attests. The plankton system is broke – not that our little pilot blooms are going to fix it, but they at least represent a careful effort to study the dynamics that could bring them back.

    Regarding the “spin” in the NSF article: it’s not that they cautioned against the redemptive potential of iron restoration. Given the size and duration of their experiment, that conservatism was natural. It was the fact that they disparagingly compared the potential mitigation effect they deduced with an apocalyptic future 700 ppm+ atmospheric CO2 scenario – a “projection” that tripled the current 120 ppm global warming increment we’ve accumulated since the start of the Industrial Revolution. In other words, it’s rather like fundamentalists saying, “so, ok, maybe condoms can stop a couple hundred million unwanted births a year, but that is totally insignificant relative to the future 15 billion population explosion that we project.”

    And for the record, I wasn’t using the word “shout” to characterize Mr. Lipow’s “scientifically-based criticism” but rather his preemptive bold-face blog headlne that declared our restoration efforts are “polluting” and that RealClimate scientists uniformly agree and disapprove.

    It just seemed to be a very loud, unilateral and hopefully premature announcement about a very respected group’s unanimous opposition to an approach that still seems like it’s being discussed in good faith here.

  43. 93
    Chuck Booth says:

    Re # 92 As this is getting a bit off-topic, I’ll make one final post on this subject. I don’t know that any scientific source is unimpeachable, but I will stick to the peer-reviewed literature.

    Estimating ocean primary productivity on a global scale is certainly not simple, but methods are established, as described in:

    Biogeochemical Controls and Feedbacks on Ocean Primary Production

    Paul G. Falkowski, Richard T. Barber, Victor Smetacek
    Science 10 July 1998:
    Vol. 281. no. 5374, pp. 200 – 206 (listed as Free Access)

    …Together with knowledge of sea surface temperature, incident solar irradiance and mixed layer depths, chlorophyll data can be used to estimate NPP for any region of the ocean…Results of such calculations suggest that global oceanic NPP is ~45 to 50 Pg C per annum… This carbon flux is driven by a phytoplankton biomass of ~1 Pg C, which is only 0.2% of the photosynthetically active C biomass on Earth…

    See also the Field et al (1998) paper I cited earlier:

    Primary Production of the Biosphere: Integrating Terrestrial and Oceanic Components
    Christopher B. Field, Michael J. Behrenfeld, James T. Randerson, Paul Falkowski
    Science 10 July 1998:
    Vol. 281. no. 5374, pp. 237 – 240

    The most recent estimates of global marine primary productivity are probably found in the latest edition of Falkowski’s textbook on this subject (I haven’t read it yet):

    Falkowski, P.G. and J. A. Raven. 2006. Aquatic Photosynthesis (2nd edition). Princeton University Press. Princeton.

    As Paul Falkowski (Rutgers Univ.) is one of the world’s foremost authorities on marine primary productivity, his assessment of the potential for phytoplankton remediation of atmospheric CO2 levels is worth considering:

    The Global Carbon Cycle: A Test of Our Knowledge of Earth as a System

    P. Falkowski, R. J. Scholes, E. Boyle, J. Canadell, D. Canfield, J. Elser, N. Gruber, K. Hibbard, P. Högberg, S. Linder, F. T. Mackenzie, B. Moore III, T. Pedersen, Y. Rosenthal, S. Seitzinger, V. Smetacek, W. Steffen

    Science 13 October 2000:
    Vol. 290. no. 5490, pp. 291 – 296

    Motivated by the rapid increase in atmospheric CO2 due to human activities since the Industrial Revolution, several international scientific research programs have analyzed the role of individual components of the Earth system in the global carbon cycle. Our knowledge of the carbon cycle within the oceans, terrestrial ecosystems, and the atmosphere is sufficiently extensive to permit us to conclude that although natural processes can potentially slow the rate of increase in atmospheric CO2, there is no natural “savior” waiting to assimilate all the anthropogenically produced CO2 in the coming century… Potential remediation strategies, such as the purposeful manipulation of biological and chemical processes to accelerate the sequestration of atmospheric CO2, are being seriously considered by both governmental bodies and private enterprises. These mitigation strategies will themselves have unknown consequences and must be carefully assessed within the context of an integrated systems approach before any action is taken.

    Many of Falkowski’s papers on photosynthesis in the sea are available as PDF’s at his laboratory’s web site:

  44. 94
    C. W. Magee says:

    Re 63:
    Will deglaciation of the Himalayas and parts of Greenland increase the silicate weathering cycle by exposing glacial rock powder to chemical weathering? Has anyone quantified such an effect?

    Re Dr. Kubiak’s description of research to date:
    We don’t doubt that y’all can increase marine photosynthesis. The question is what happes to the carbon after the bloom. I hope you are able to continue your research. While we understand your need to generate interest to pay for your work, us conservative type scientists are uneasy with claims that haven’t yet been substantiated.

  45. 95
    Nick Gotts says:

    Re #76


    I think you’re doing just what you implicitly warn others against -
    placing cherished beliefs above the need to combat anthropogenic
    climate change. In your case, the central beliefs are that “economic growth” is
    in itself a good thing, more economic growth is better, and markets
    are fundamentally benign.

    I put the phrase “economic growth” in scare quotes because it is
    not clear there is anything close to a definitive way to measure the
    size or growth rate of an economy – particularly in the case of
    economies like China and India, which are still to a great extent
    based on kinship and tribute relationships rather than production for profit.
    GDP, the most widely cited measure of the former and basis for
    measuring the latter, measures the amount of monetised activity – it
    excludes subsistence farming, unpaid housework and care for family
    members, and (as measured rather than by definition) much of the
    informal economy; and takes no account of the destruction of natural
    capital through environmental damage, or human capital through damage
    to health, and social disruption.

    The extremely rapid GDP growth rates currently quoted for China and
    India reflect partly the outsourcing of manufacturing and in India’s
    case service industries by rich-country corporations to take advantage
    of cheap labour and lax environmental regulation, but above all
    the speed with which domestic economic activity is being
    monetised, a process which is benefiting the ruling elites and a
    middle class minority (admittedly, this minority is large in absolute
    terms, given the huge populations involved), at the expense of the
    poorer peasantry, landless rural workers, and urban poor. I’m not
    saying these countries don’t need economic growth, but most of it at
    present is going into prestige infrastructure – much of it of dubious quality
    and value – and luxury goods for a minority, not improving the
    desperate conditions of the poor. Many of these luxuries (cars, air travel,
    beef and other meat) are particularly destructive in climatic
    terms. Rates of 8% growth per annum for the next 25 years, as you say
    the Chinese government plans, seem to me a fantasy. The British economic writer
    and journalist Will Hutton (whose position on the left-right spectrum
    I should judge is pretty close to yours) has recently published a book
    on China, “The Writing on the Wall: China and the West in the 21st
    Century”, claiming to show that the efficiency of capital
    investment in China is both very low, and falling rapidly. (I should
    say I haven’t read the book, only articles putting forward its
    thesis, and there is much in the latter I don’t agree with. There’s a
    discussion between Hutton and Meghnad Desai at I
    would be very surprised if China gets through the next 25 years
    without large-scale social and political upheaval; and if either China
    or India does so without a considerable fall from current GDP growth

    If I’m wrong, however, they’ll do it powered largely by coal,
    not nuclear power or renewables: they both have large coal reserves,
    and cheap labour to extract it and build the relatively simple
    infrastructures needed to use it. Neither has sufficient uranium to
    fuel a large-scale increase in nuclear power, neither is likely to
    want to be dependent on uranium imports. The People’s Daily online
    ( says
    “Slightly more than 1 percent of China’s total electricity needs are
    met by nuclear power plants but this is set to surge to 4 percent by
    2020.” Some surge, eh? Dr.R.Chidambaram, Chairman of India’s Atomic
    Energy Commission says
    ( that India
    needs to expand electricity generating capacity to 900GWe, and that
    there are plans for nuclear plants to produce 20GWe by 2020. The
    Indian AEC page is full of plans for using thorium, of which India has
    plenty, but it’s quite clear these won’t be implemented for some
    decades at least. Hence my belief that the most vital area of
    technical advance in combating GHG emissions is probably carbon
    capture and sequestration.

    You say, not for the first time, that we need rapid economic growth in
    order to fund mitigation. Yet the only large region to reduce GHG
    emissions significantly during the 1990s was the former USSR – due to the
    contraction of economic activity. You are claiming, without evidence
    or argument so far as I can see, that if economies only grow fast
    enough, resources will be more readily diverted into mitigation – and
    on a scale large enough to outweigh the increased energy demand. Can
    you spell out your reasons for believing this? I think that without a
    fundamental reorientation of socio-economic and political systems,
    more growth will simply mean faster GHG emissions increase.

    Turning to markets, you claim they are much harder to manipulate than
    governments. Markets are manipulated by setting their boundary
    conditions – who is allowed to take part on what terms. Economic
    interest groups pressure governments to set these conditions to their
    advantage. You can see this quite clearly in agricultural markets -
    where both US and EU producers have ensured that competition from poor
    countries is kept out; and in the area of so-called “intellectual
    property”, where the US government, at the behest of media, software
    and similar corporations, is pressuring other governments to adopt rules which
    favour those corporations – notably, continual extensions to the term
    of copyright, and to what can be patented.

    You do put your finger on one of markets’ fundamental
    flaws – their short-termism. That is something we simply cannot afford
    in the current emergency. Among their other flaws the most important
    is that, even setting aside the ability of corporations to determine their
    institutional context by their influence over governments,
    they intrinsically give more influence to the rich than the poor – that is,
    in current terms, they privilege the preferences of those doing most
    of the damage over the preferences of those bearing most of the costs,
    at least in the short to medium term. (Incidentally, a lot of people
    did very well out of the dot-com and housing bubbles, and in the
    latter case, many are still doing so. A lot of the time, markets simply
    reward luck. I should declare an interest here: I’m one of those who
    has done well out of the UK’s still expanding housing bubble, simply
    by having parents who used a relatively small legacy to buy a house in
    suburban London in the 1960s.) Market mechanisms can be put to good use,
    but they need to be limited in scope, and kept under democratic
    control. In the current era, that control needs to be global in scope
    - to deal with many issues, but most of all climate change, we need to
    build global democratic institutions, in which so far as possible, the
    Chinese, Indian, South American and African poor have equal say with
    us, the rich. Are you ready for that?

  46. 96
    Ray Ladbury says:

    Have you ever been to India, China, or Africa? Do you really think that people will ever voluntarily choose poverty? I don’t, and I lived in SubSaharan Africa for 2 years doing development work and have traveled in India, China, and Latin America. In the end, it does not matter what I want. It does not matter what you want, or George Bush, or the UN or the EU or even the governments of China, India, etc. People will do what they need to to better their lot. If their governments support them, those governments will survive, and if not they will be overthrown. I did not say that I thought the level of growth seen in China was sustainable. I said that that was what the Chinese governement thinks they need to sustain themselves in power. I don’t see them voluntarily taking actions that will get them booted out.
    So the struggle for economic growth in the short term will continue independent of what you or I think it ought to do. We cannot change that–or if you think we can, I’d be interested in hearing your plans. What we just may be able to do is channel it into less energy-intensive and particularly less ghg intensive avenues. And if we are going to do that, then it will take investment on our part–and guess what, you don’t get money to invest if your economy is stagnating.
    Actually, it may surprise you, but I am quite a bit left of center–at least in the US political spectrum. I distrust markets, but I distrust them less than social engineering–which you must admit has a really lousy track record. And in any case, markets exist, whereas to rely on some other framework would require us to set up that framework–a process that will take time we don’t have and that can be manipulated by those seeking to enrich themselves.

    To quote you: ” Markets are manipulated by setting their boundary
    conditions – who is allowed to take part on what terms. Economic
    interest groups pressure governments to set these conditions to their

    Hmm, who are the interest groups pressuring…? Governments. It is the regulation of the market that is most vulnerable to the manipulation–and yes, I am not blind to the paradox that the regulation is essential to the reasonable functioning of the market as well. It is merely there where the need for transparency is greatest.

    So, ultimately, it does not matter what I would prefer–which if you get right down to it would be to be left alone to pursue my scientific research and launch satellites and walk my dogs and generally live a quiet life. What WILL HAPPEN is that economies in India, Africa, China and Latin America will grow–both in absolute terms and relative to the US, Japanese, Korean and European economies. Those regions (though perhaps not their poor) will have greater influence, and unless we work with them and help them achieve growth WHILE reducing greenhouse gas emissions, we will reach a tipping point where any future argument will be purely be about who gets the blame.

  47. 97
    Nick Gotts says:

    Re #96 Ray,
    I spent 4 months in Africa in 1991, trying unsuccessfully to become an environmental journalist, and saw absolutely dire poverty in rural Zimbabwe and the squatter camps round Durban. As I said, current development paths in most poorer countries are doing little for the poor in those countries. As I also said, I do not deny that those countries need economic growth, or that our governments need to work with theirs. What I do say is that fetishising economic growth as you do is disastrous, and you don’t address the point that without a fundamental change of orientation, faster economic growth simply means faster growth in GHG emissions. I don’t know what you mean by “social engineering” – passing a law, organising a political lobby or campaign, or founding a corporation, pressure group, publication or chess club, – so far as I can see, these are all social engineering. Indeed, my point about markets and governments could be expressed by saying that all markets are in large part the outcome of social engineering – the very idea of a “free market”, existing outside a framework of social institutions which results partly from conscious human decision-making, is an ideological fiction. Again, as I said, market mechanisms can be useful – but we can’t leave the major decisions about capital investment to them because if we do, those decisions will be taken to maximise profit for particular corporations, not to reduce GHG emissions. Even many of the decision-makers in big business, I believe, do or will see this – as they did in WW2.

  48. 98
    Ray Ladbury says:

    Nick, put several people with different merchandise together and you will get a market. It is human nature to trade. It is not that markets exist outside of human conventions and social institutions–they are an inate part of them. It is also human nature to act in accord with what one perceives to be ones interests–and usually ones immediate interests. I don’t trust any system or framework that expects people to do otherwise.
    I like markets for one reason: they work. They are chaotic, turbulent and ultimately uncontrollable, but they work. They can be distorted and made dysfunctional, but ultimately they punish such transgressions. That is not fetishization. It is empirical fact–and it can also be modeled. Markets do not take a short-term view. People in markets do–and if it’s wrong to take a short-term view, then those people get punished. And no, it is not a result of conscious decision making, it is a result of some pretty simple and immutable laws. Show me one command economy that has prospered. Certainly not Zimbabwe, as I’m sure you saw. Not even Tanzania, although Julius Nyerere was arguably one of the most decent men ever to govern a nation. Command economies do not work because they rely on humans to prognosticate the future, and we’re lousy at that. You advocate “deciding” on a mix of technologies to pursue to diminish our ghg emissions from energy. When you make such a decision, you prejudge future developments. So, do you go with 100% solar arrays? What if they can’t keep up with demand? Do you bet on fusion supplying an endless amount of clean energy? What if it doesn’t pan out. In a command economy, the decision-maker has a stake in proving he was right. In a market economy, anyone that stubborn winds up a pauper. And just who are you going to get to make such a momentous decision. I wouldn’t want the job and I’d distrust anyone who did want it. In any case, it’s a purely academic point. If you expect the world to come together and suddenly agree on a strategy, it won’t happen. Under rare circumstances, individuals are capable of altruism, nations are capable of only self interest.

  49. 99
    Nick Gotts says:

    Re #98 I’m not arguing for a command economy, but for negotiated coordination – which is already a large part of how capitalist societies work, particularly when there is a widely agreed common goal. It is also a major part of how large corporations work internally. The situation we are now in is at least as serious as WW2, when none of the allied governments was daft enough to leave major investment and R&D decisions to markets – if they had, the Axis would probably have won. Decisions were not immutable, and institutional provision was made for revising them. Nor has the USA left production decisions to markets since WW2 when its security was perceived to be at stake – it’s no accident that only states and the public-sector body ESA have been able to fund and develop space programmes, nor that the US military developed the key technologies for the internet (and CERN, another non-market institution, those for the web). However, both WW2 and the Cold War produced authoritarian tendencies, which is one reason for insisting on far better democratic oversight than we had then. Markets have not so far punished polluters – in fact, it is quite generally more profitable to pollute than to avoid polluting. Nor did they punish slavers or colonialists. I gave clear examples of the conscious decision-making involved in determining markets’ institutional frameworks – there’s no immutable law that says whether software can be patented, or whether there should be import tariffs on particular products. Finally, I’m not counting primarily on altruism, but on enlightened self-interest – individual and institutional. As I’ve said before, we’re in a position where all agents with more than a 20-30 year time horizon have, objectively, a strong common interest. That doesn’t make agreeing a broad strategy internationally easy, but it does in my view make it a realistic possibility. Details don’t need to be agreed, nor do all states have to make the same technological choices. For example, although as you know I’m not at all keen on nuclear power, I recognise there’s no likelihood France or Japan are suddenly going to drop it. What we need at that level and in the near future is at a minimum some agreed emissions targets (which will undoubtedly be too weak initially), and ways to monitor them. Agreements on technology sharing would be an important bonus. I think we’ll need much more later – but by then we’d be building on existing achievements, and probably in the wake of much more obvious climatic change. The best model we have is the Montreal Protocol – not perfect, and as someone noted recently on this site, the Chinese government are taking advantage of a loophole – but without it we’d already be well on the way to destroying the ozone layer completely.

  50. 100
    Ray Ladbury says:

    Nick, I am a firm believer in a role for government. However, I am also mindful that governments can be co-opted when their actions infringe on the privilege of the powerful–and even when they infringe on the privilege of the electorate. Markets are also not immune, but because they are decentralized, they have greater immunity and tend to recover more quickly (and sometimes painfully). We need to be mindful that governments respond to a variety of needs, some of which will be more pressing on the timescale of elections than controlling ghg emissions. The failure of the Clinton administration wrt Kyoto comes to mind. They were the ones who got the whole carbon trading language in there in the first place. They held firm in negotiations but buckled in the face of opposition from the Senate.
    Montreal was a cake walk compared to this. You are talking about China and India giving up their main energy resource–coal, at a time when they feel they need to dramatically increase energy consumption just to maintain order. And if India and China are not on board:
    1)any agreement will be meaningless
    2)you can kiss off any hope of the US being party, as well.

    Economic growth in developing countries is the only hope we have of getting at least some of the poor out of poverty. Economic growth in developed economies is the only hope we have of maintaining influence and channeling growth in developing economies. Not to mention that a prosperous economy will be more likely to be able to pay for the R&D and mitigation needed to get through this period. That is not fetishization. That is reality. Leaving aside the question of whether it would be desirable for humans to learn to live in an economy without “growth” per se, nobody knows how to do it and prosper. When growth stops, social welfare declines, as does influence on the world stage. Also, I draw a distinction between economic growth and growth of resource consumption. I think it is possible to have the former without the latter, since economic growth is just the increase in the total value of goods and services produced. Produce goods and services people are willing to pay for and your economy grows even if you don’t produce more of them.

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