Forget CO2 and Milankovitch cycles, new study says dust in the wind drives climate

From the Universitat Autonoma de Barcelona  a suggestion that ocean CO2 sequestration  is driven by iron laden dust blown into the oceans that cause phytoplankton blooms, resulting in the ocean as a CO2 sink. It’s another take on the proposed experiment from a  couple of years ago where a researcher wanted to drop a barge of powdered iron into the ocean to watch what happens. It was actually tried, and was reported to be a failure.

Dust in the Mediterranean

Dust in the Mediterranean - Image NASA

Climate in the past million years determined greatly by dust in the Southern Ocean

A group of scientists led by researchers from the Universitat Autònoma de Barcelona (UAB) and the Swiss Federal Institute of Technology (ETH Zürich) has quantified dust and iron fluxes deposited in the Antarctic Ocean during the past 4 million years. The research study published in Nature evidences the close relation between the maximum contributions of dust to this ocean and climate changes occurring in the most intense glaciation periods of the Pleistocene period, some 1.25 million years ago. Data confirms the role of iron in the increase in phytoplankton levels during glacial periods, intensifying the function of this ocean as a CO2 sink.

Dust, formed by particles of soil, plants, etc. affects the climate by altering the energetic balance of the atmosphere and provides iron and other micronutrients necessary to marine organisms. Scientists considered that dust fluxes deposited by the wind into the Antarctic Ocean increased during glacial periods and that iron fertilisation may have stimulated marine productivity, contributing significantly to the CO2 reduction in the atmosphere during the most recent Pleistocene glacial periods (in the past 800,000 years). However, the magnitude of these effects and their role in the evolution of the climate system had remained unclear.

Records of the period studied in this research work – the longest and most detailed up to date on the Southern Ocean – reveal a sharp increase in dust and iron inputs during the Climate Transition of the Middle Pleistocene Epoch (1,250,000 years ago) in which fluxes tripled. This transition marked a global climate change with the beginning of glacial periods lasting 100,000 years, in comparison to the gradual intensification of glacial cycles occurring in the three million years immediately before, when periods lasted 41,000 years.

For the first time results show the close connection between the highest levels of dust deposited in the Antarctic Ocean and the lowest concentrations of CO2 in the atmosphere, which gave way to the appearance of the deep glaciations typical of Earth’s recent history. The study indicates that the dust most probably played a key role in fertilising microscopic algae of the Southern Ocean, emphasising its role as a CO2 sink. These microorganisms grow uptaking the CO2 found in the atmosphere and when they die they sink releasing carbon into the depths of the ocean.

For Antoni Rosell Mele, ICREA researcher at the Institute of Environmental Science and Technology of UAB, and Alfredo Martínez Garcia, currently researcher at EHT Zürich who earned his PhD at UAB, the research carried out offers new clues on the causes behind the most intense glaciations of the Pleistocene Epoch, particularly on how interactions between dust with oceanic biology influence CO2 and the climate. It also allows scientists to understand how future changes in atmospheric circulation and the superficial biology of oceans can make the Antarctic Ocean change the efficiency with which it captures and removes carbon dioxide from the atmosphere.

There are in fact initiatives to fertilise the Southern Ocean with iron with the purpose of reproducing the natural process observed during glaciations and reduce today’s levels of CO2 in the atmosphere. It is an issue which has generated much controversy. “Although our data indicates that this process occurred naturally during glacial periods, we must take into account that ocean circulation was completely different to what it is now, and this made the role of iron fertilisation more efficient in capturing carbon dioxide from the atmosphere. There are also several unknown aspects of what could happen to marine ecosystems if iron were artificially added in large quantities, and therefore its commercial application continues to be unviable at the moment”, researchers conclude.

###

Researchers from the universities of Edinburgh and Princeton also participated in the research.

Caption: http://www.uab.es/uabdivulga/img/UAB_InvestigadorsPolsAntartic.jpg

Reference:

Martinez-Garcia, A.; Rosell-Melé, A; Jaccard, S.L.; Geibert, W.; Sigman, D.M.; Haug, G.H. (2011). “Southern Ocean dust-climate coupling during the past 4,000,000 years”. Nature, doi: 10.1038/nature10310.

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64 Responses to Forget CO2 and Milankovitch cycles, new study says dust in the wind drives climate

  1. polistra says:

    Wouldn’t iron dust, and the movements of iron-bearing bacteria on the ocean surface, be influenced by the magnetosphere? Could this be a secondary path for sunspot influence?

  2. ‘Wayward Son’ wanted for questioning….

  3. Dave N says:

    Beat me to it, Independent :-)

  4. Bill Illis says:

    The dust in the ice cores are the highest at periods when the glaciers stop advancing and/or are starting to melt-back – not just when an interglacial warm-up is starting but there are lots of periods when a temporary peak low/peak advance is reached and a warming trend starts.

    I have always assumed the dust was due to the loess left-behind as the glaciers are melting-back. When the loess drys out (and no vegetation is growing yet to stablilize it yet) and the wind blows (and there is likely very strong winds next to continental glacial fronts) – huge dust storms result. In addition, there is much less rainfall and vegetation during the ice ages so even the deserts are three times bigger than today.

    The glaciers are melting back at up to 5 kms per year so that leaves behind a huge amounts of small-grained sand and clay deposits covering hundreds of kilometres. A great cold sand, dried-out mud desert.

    There is less correlation of the dust to CO2 levels that the dust to these peak melt periods. I’m more inclined to blame changes in ocean temperature for the changes in the CO2 levels which is much more closely tied one-for-one-with-an-800-year-lag than the dust numbers.

  5. Ben says:

    The Treasure of the Sierra Madre Wind scene video clip:

    “Oh laugh, Curtin, old boy. It’s a great joke played on us by the Lord, or rate, or nature, whatever you prefer. But whoever or whatever played it certainly had a sense of humor. Ha! The gold has gone back to where we found it! This is worth ten months of suffering and labor!”

    Caution: Ending spoiler…

  6. ” Since the startup of Sea Water Reverse Osmosis ( SWRO ) Desalination during 1980, Middle East desalination systems are dumping Millions of Tons of Ferric Chlorode ( FeCl3 ) , pre treatment chemicals along with Sulphuric Acid ( H2 SO4 ) to Oceans & Seas. This had already created algal bloom many times in the mouth of ARABIAN GULF “

  7. Doug in Seattle says:

    Still stuck on CO2 as the driver of climate rather than a indicator.

  8. eyesonu says:

    @ Independent
    September 1, 2011 at 5:09 pm

    Truly an all time classic!

    I can’t get it out of my mind. I think the dog is now getting tired of multiple replays.

  9. Stephen Wilde says:

    Why not just accept that cooler ocean waters absorb more CO2 from the air and reduce atmospheric CO2 content along with the coolness reducing the level of activity of the entire global biosphere?

    There seems to be a desperate need to find new ways of avoiding the inconvenient implications of the most likely scenarios.

  10. Smokey says:

    Independent,

    Shouldn’t someone call the Green Police to report all that CO2 on the stage?

  11. charles nelson says:

    I have always been fascinated by Australia’s role in SH climate. It seems to alternate between being a vast sink of water/water vapour with vast inland seas river and lakes (as at present) then dries out to a baking hot arid and DUSTY continent. These wildly diverging states surely influence its role as a component in the SH climate system.
    I’m sure someone will englighten me.

  12. Keith says:

    For the first time results show the close connection between the highest levels of dust deposited in the Antarctic Ocean and the lowest concentrations of CO2 in the atmosphere, which gave way to the appearance of the deep glaciations typical of Earth’s recent history. The study indicates that the dust most probably played a key role in fertilising microscopic algae of the Southern Ocean, emphasising its role as a CO2 sink.

    Because they’ve got it arse about face, as per usual. Colder => drier, drier => dustier. Also, colder => more oceanic CO2 absorption. That’s what the evidence actually points to in the real world.

    In their world, dustier => less atmospheric CO2, less atmospheric CO2 => colder. Does their study have anywhere near the resolution to demonstrate a reversal of the usual order?

  13. RockyRoad says:

    Let me get this straight–they’re saying, whatever the mechanism, that a reduction in CO2 caused the last Ice Age?

    And we’re trying to limit, I say limit CO2 in the atmosphere?

    Is somebody nuts? (Or perhaps they just have an insatiable fetish for glacier skiing!)

  14. Grey lensman says:

    This is a very important post, well done. The very first link shows the shortage of deep simple scientific thinking. The experiment worked because at the very top of the chain is the whale and dead whales sink to the bottom as do the plankton that are not eaten. Plus look at the general growth of life.

    Secondly the dust. Natural Geographic did a program on the Bahamian Blue Holes. They discovered that a massive dust storm, rich in Iron enveloped the Islands about 12,000 years ago. This at the time of the Younger Dryas period. This resulted in the extinction of many species of animals on the Islands, the arrival of humans and the extinction of the Clovis culture on the mainland.

    The case for Iron seeding and the link to particulates having a major effect on climate, is very clear. As is the selective ability of modern science.

  15. Ray says:

    It is still our fault because all we are is dust in the wind…

  16. John says:

    There was a study in Science magazine in the late 1990s which found that at the beginning of the last ice age, areas in Patagonia got drier and windier, and about 50 times more dust from Patagonian deserts blew into the south Atlantic ocean. Over a period of several thousand years, the steady supply of iron on the dust particles provided the nutrient which limited growth of phytoplankton in its absence. Gradually, CO2 levels were reduced, as the remains of phytoplankton and their grazers fell to depth. Some of this detritus (containing carbon and oxygen) ended up in the seabed, but most were consumed by bacteria, and the carbon was released as CO2 in the deep ocean. After several thousand years, the oceans contained enough additional CO2 that atmospheric levels were reduced by 40 ppm. That isn’t actually very much, in comparison to the roughly 110 ppm increase that we’ve seen in the last 200 years, but it is nonetheless remarkable.

    Iron seeding experiments aren’t failures; they show that in parts of the southern ocean which are iron limited, the addition of iron can stimulate huge amounts of phytoplankton growth, followed by explosions of their grazers, zooplankton.

    The reason that seeding southern oceans with iron won’t be a panacea for increased CO2 emissions is that if we were to try to reduce atmospheric CO2 by enough to make a difference, in decades rather than in millenia, we would create dead zones in the Antarctic, places without enough oxygen for species to live. The bacteria need oxygen to consume the detritus falling from the ocean surface. Over a thousand years, however, iron seeding would be a workable idea.

    Better to see if we actually have a big problem, and if we do, then come up with a better solution. The current rate of warming is currently far below the IPCC projections for the amounts of GHGs and black carbon and ozone and methane that have been emitted in the last 100 years or so.

  17. John from CA says:

    Where’s Anna these days — best of the WUWT comments?

    When Sun’s Too Strong, Plankton Make Clouds
    http://www.nasa.gov/vision/earth/environment/0702_planktoncloud.html

    LOL, they are now discovering iron dust bloom implications on cooling? Is the entire Scientific community functioning in a different timeframe or are they all deaf to their own research?

  18. David Falkner says:

    These microorganisms grow uptaking the CO2 found in the atmosphere and when they die they sink releasing carbon into the depths of the ocean.

    Ok. Then what happens to the carbon? The ocean circulation patterns takes it up and dumps it out to the atmosphere? It sits in a neat little package? Oceanic carbon gnomes play carbon tennis? It sinks to the ocean floor, never to be released? And if these phytoplankton blooms capture carbon and then release it into the ocean, why are PH levels neutralizing when the blooms are at a lesser state?

    Also, what’s the explanation for the failure of the experiment where they tried to seed the phytoplankton with iron?

  19. JinOH says:

    So true – excellent tune. ;)

  20. John from CA says:

    So let’s see if we can put 2 and 2 together without the need for a computer model that pooches the result.

    What exactly is the Universitat Autonoma de Barcelona study suggesting and which of the moronic Green groups do we need to tie to their beds so they don’t Pooch the Puppie and destroy our planet with stupid schemes?

  21. Paul S says:

    I remember my biology teacher at high school in 1984 telling us that it had been suiggested that dumping a ship load of iron oxide in the ocean could cause an ice age due to the sudden increase in phytoplankton. This is obviously an old and unoriginal idea.

  22. Grey lensman says:

    David said

    Quote

    Ok. Then what happens to the carbon?

    Unquote

    Over time, as climate is, it forms chalk, limestone and marble or coal or some oil.

    It’s rocket science

  23. Rational Debate says:

    Geoengineering by dumping iron into the ocean is just begging for a nasty emergence of the Law of Unintended Consequences. Sure, too little iron can be limiting – but in most biological systems, too much iron strongly promotes inflammatory responses which wreak havoc on organs and systems, and then causes death.

    Meanwhile, these guys are already behind the times – some new players are in town. 8-) Well, ok, they’re NOT new to town, they’ve been here but gone unrecognized and I’m sure many more are just waiting for discovery. I was about to post the following article to tips & notes, but seems applicable here too…

    Up from the depths: How bacteria capture carbon in the ‘twilight zone’
    September 1, 2011 http://www.physorg.com/news/2011-09-depths-bacteria-capture-carbon-twilight.html

    Located between 200 and 1,000 meters below the ocean surface is a “twilight zone” where insufficient sunlight penetrates for microorganisms to perform photosynthesis. Details are now emerging about a microbial metabolic pathway that helps solve the mystery of how certain bacteria capture carbon in the dark ocean, enabling a better understanding of what happens to the carbon that is fixed in the oceans every year. They appear in the September 2, 2011, edition of Science.

    Understanding the flow and processing of carbon in the world’s oceans, which cover 70 percent of Earth’s surface, is central to understanding global climate cycles, with many questions remaining unanswered. Between 200 and 1,000 meters below the ocean surface exists a “twilight zone” where insufficient sunlight penetrates for microorganisms to perform photosynthesis. Despite this, it is known that microbes resident at these depths capture carbon dioxide that they then use to form cellular structures and carry out necessary metabolic reactions so that they can survive and reproduce. Details are now emerging about a microbial metabolic pathway that helps solve the mystery of how certain bacteria do this in the dark ocean. (continued)

  24. Kaboom says:

    Of course the validity of their math hangs by the sinlge thread of climate sensitivity to CO2 levels, which is most likely seriously overstated and most likely non-linear. That’s after proving the effect of iron particles to trigger carbon dioxide sink events (threshold particle size, anyone?).

  25. dscott says:

    While we are speculating, if a magnetic reversal should happen, the amount of cosmic rays entering the atmosphere would increase thus causing more cloud formation. The South Atlantic anomaly is getting bigger as a precursor to the event. Add in the extra dust and you got even more cloud formation, walla an Ice Age. It is quite possible that a chain reaction is set up where an individual factor is not enough in itself to change the climate but a series of factors lined up at just the right orientation and quantity starts a cascade effect. CO2 may be a part of that cascade effect given that CO2 is one necessary ingredient for a phytoplankton bloom.

  26. David Archibald says:

    Idiotic. The deep oceans are relentlessly oxidising. The oxygen minimum is party way down the from the edge of the continental shelf. The ice age-related change in CO2 level is fully explained by the temperature change of the top 1,000 metres of the oceans.

  27. Michael Schaefer says:

    Hmmmmm –

    wouldn’t cold, dry climate conditions over a long period of time intensify duststorms and, hence, the influx of dust and Iron into the oceans, rather than vice-versa?

    I think, this study is only proof of yet-another case of muddled, mistaken cause and effect:

    It’s not dust causing cold, like stated, but cold causing dust.

  28. Michael Schaefer says:

    polistra says:
    September 1, 2011 at 5:12 pm

    Wouldn’t iron dust, and the movements of iron-bearing bacteria on the ocean surface, be influenced by the magnetosphere? Could this be a secondary path for sunspot influence?
    —————————————————————————–
    Sorry to contradict you, but Fe2O3 is not magnetic.

  29. Bob in Castlemaine says:

    It’s the aerosols from Chinese power stations that have caused the cooling “travesty”, but the science is settled.
    No it’s soot from Diesels that we must worry about, but the science is settled.
    Now it’s the iron dust that we must fear, but the science is settled.
    Seems the only thing we can be sure of is that it’s all bull dust, and that the science sure ain’t settled!

  30. John Marshall says:

    several million tons of dust from the Sahara blows onto the Arizonan basin every year to help fertility but climate?

  31. Willie S. says:

    The drift of this posting is evidently that if dust is a factor in climate change, then CO2 is not. But there is no reason why both dust and CO2 cannot be factors, and in fact any climate scientist will tell you that a myriad of factors at all times are operating to produce climate.

    And of course the science isn’t settled. We keep learning more and more. And what we are learning keeps pointing to the same conclusion: that increasing levels are atmospheric CO2 are a powerful forcing that is producing climate change.

  32. Siliggy says:

    When the planet passes through the next large cosmic dust cloud lets hope we have enough heat and CO2 to survive the sudden endothermic photosynthesis cooling and following CO2 shortage.

  33. Robertvdl says:

    Time To Cut Off Funding For Mad Scientists

  34. Andre says:

    It appears that we have some problems here, first, the dating of the iron/dust tripling is suggested to be 1.25 Ma to be causal for the mid pleistocene transition, which happened 0.9Ma – 1,0Ma, see for instance: http://earth.geology.yale.edu/~avf5/teaching/ResourcesGG523/Lect2.intro.climate.history.pdf
    (slide 14)
    I think a delay of 250,000 years is a bit tough to explain, even when accounting two sigma errors.

    Also compere the work to Seki et al 2010
    http://environ.lowtem.hokudai.ac.jp/saishin.pdf/Seki2010EarthPlanetarySci.Lett.Alkenone%20and%20boran-based%20Plicene%20pCO2%20records.pdf
    who do not mention the drop in their multi proxt appraoch albeit that it is visible in fig 1c and 9c as a minor event nullified by a drop of maybe 100ppmv around 5Ma

    Furthermore there is indeed a further suggestion of a CO2 drop during the mid Pleistocene transition in Hönisch et al.2009, Science 324 (5934): 1551-1554), of which van de Wal and Bintanja find a sensitivity of 0.15K for one ppmv, or roughly 30-40 degrees K for doubling CO2, attributing this to albedo feedbacks.

    http://www.sciencemag.org/content/324/5934/1551.short/reply#sci_el_12537

    Maybe they should read up on the limits of feedbacks (in other words baloney).

  35. Robertvdl says:

    Question. To have so much ice http://www.iceagenow.com/Ice-Age_Maps.htm how much snow has to fall and in what time frame ?

    During the last ice age, sea levels dropped around 450 feet.

    That means that there must have been a lot of precipitation and not only snow.

    We see the dust at the end of an Ice-age not at the beginning.
    http://en.wikipedia.org/wiki/File:Vostok_Petit_data.svg

  36. Didjeridust says:

    Just so I get this logic perfectly clear:
    Removal of CO2 from the atmosphere will make the world cooler while insertion of CO2 into the atmosphere will not make the world warmer?

  37. 1DandyTroll says:

    So, essentially, the green solution to save the planet from dangerous CO2 driven catastrophes like “that ocean CO2 sequestration is driven by iron laden dust blown into the oceans that cause phytoplankton blooms, resulting in the ocean as a CO2 sink.” is to try and enhance that very same so called negative effect of CO2 that they want to save us from in the first place. And, of course, they want to be funded by taxes trying to change the climate so they can save the planet from climate change.

    Are they still closing down insane asylums to save tax money, I wonder.

  38. Alberta Slim says:

    Speaking for Al Gore–

    “Dust and iron particles in the ocean?……. Bulls**t
    Fertilizing photoplankton?…………………….Bulls**t
    CO2 sinking to ocean depths?………………Bulls**t
    Bulls**T, Bulls**t Bulls**t…..
    Where is my Jack Daniel’s?”

  39. Bruce Cobb says:

    Willie S. says:
    September 2, 2011 at 1:15 am

    The drift of this posting is evidently that if dust is a factor in climate change, then CO2 is not. But there is no reason why both dust and CO2 cannot be factors, and in fact any climate scientist will tell you that a myriad of factors at all times are operating to produce climate.

    It all depends on how much you “need” for C02 to be a factor in order to support your playstation GCM models, doesn’t it? Of course climate is complex, but in the rush to round up the usual suspects, C02 is just an innocent bystander.

    And of course the science isn’t settled. We keep learning more and more. And what we are learning keeps pointing to the same conclusion: that increasing levels are atmospheric CO2 are a powerful forcing that is producing climate change.

    “We” aren’t learning anything if “we” just keep assuming that C02 is a climate driver. These “scientists” are simply exhibiting a rampant case of bias confirmation.

  40. Bruce Cobb says:

    Didjeridust says:
    September 2, 2011 at 3:43 am

    Just so I get this logic perfectly clear:
    Removal of CO2 from the atmosphere will make the world cooler while insertion of CO2 into the atmosphere will not make the world warmer?

    Where do you get the idea that removing C02 “will make the world cooler”? It is illogical to try to show false logic based on a false premise.
    The relationship of C02 to either cooling or warming is primarily one of correlation. Warmists always seem to have trouble with that.

  41. RockyRoad says:

    The best source of dust I can think of would be the larger volcanic erruptions–for example Yellowstone. That puts an amazing amount of rock volume at dust particle size high in the air for world-wide distribution. So whatever the iron in that dust does to the biosphere, volcanoes likely are the largest source and have the greatest impact.

  42. Robertvdl says:

    Didjeridust says
    “Just so I get this logic perfectly clear:
    Removal of CO2 from the atmosphere will make the world cooler while insertion of CO2 into the atmosphere will not make the world warmer?”

    No no Removal of CO2 from the atmosphere makes the world warmer. Just when there is more dust and less CO2 temperatures go up and with more CO2 and less dust cooling starts
    http://upload.wikimedia.org/wikipedia/commons/c/c2/Vostok-ice-core-petit.png
    http://ncwatch.typepad.com/.a/6a00d83451e28a69e201310f43617b970c-800wi

  43. Bill Illis says:

    Since I have the data, I thought I’d post up Temperatures, CO2 and Dust concentrations from the ice cores for the last 4 ice ages (dust isn’t available beyond that).

    It is pretty clear that CO2 is tied to temperature and not to Dust. Try again boys.

    http://img9.imageshack.us/img9/5009/iceagesdusttemps.png

    The decline in CO2 when an ice age starts (from 275 ppm to 200 ppm within 20,000 years and thus represents the vast majority of the change in CO2) is not associated with any Dust peaks at all. The Dust occurs in the coldest periods and also when those cold periods are transitioning to warmer periods – at times when CO2 levels are going back up again, not being drawn down.

  44. Nuke Nemesis says:

    For those of you trying to figure things out, the one thing you can take away from this is the science is far from settled. Additionally, it also shows the claim that all other factors except CO2 were eliminated as possible causes of the recent warm period.

  45. Ulric Lyons says:

    @Bill Illis says:
    September 1, 2011 at 5:45 pm

    “The dust in the ice cores are the highest at periods when the glaciers stop advancing and/or are starting to melt-back..”

    Good. This can be seen at a seasonal scale. Larger dust storms from desert areas will occur on strong spring warming bursts AFTER colder winters.

  46. This theory is as RIDICULOUS as the man made global warming CO2 theory.

    Any dust would be the result of climate change not the initial cause.

  47. Agan their premise is wrong, which is co2 concentrations DO NOT drive the climate. Idiots!

  48. Thierry says:

    It is more logical to think that the climate drives the dust in the wind, not the other way around.
    Colder climate = more powerful polar mobile highs (MPHs) originating from the poles and migrating towards the equator = more powerful tropical moisture streams (thus charged in dust) migrating towards the north on the leading edge of the MPHs.
    Why does nobody read Marcel Leroux books on the Climate dynamics where he explains why et how MPHs are the real climate drivers…

  49. It just keeps going on and on, the complete utter ridiculousness these idiots keep coming up with for causes of climate change. This is PATHETIC.

    They are beyond clueless. It is the sun, it is Milankovitch Cycles for the major glaciations, combined with a prolong solar minimum which sets the tables for the items that control the climate to phase into a cold mode, which independent of Milankovitch cycles, is enough to cause the small climatic cycles and sometimes abrupt climatic changes..

    Those items being

    SOI INDEX- LA NINA VERSUS EL NINO

    VOLCANIC ACTIVITY
    AO/NAO/.AAO ATMOSPHERIC CIRCULATIONS TO NAME SOME
    PDO/AMO

    COSMIC RAYS -CLOUDS

    EARTH’S MAGNETIC FIELD STRENGTH

    With all the above, if the degree of magnitude is strong enough and long enough then all of those factors will conspire to increase earth’s albedo through more low cloud cover,greater snow cover and more precip. which causes the temperature to change. Sometimes thresholds are met which explains the abrupt climatic changes.

    Their Asinine theory, of dust versus co2 , does nothing to explain the many abrupt climatic changes that have constantly impacted the earth ,never mind change to climate itself. This is beyond stupid!

  50. Bruce Cobb says:

    “The study indicates that the dust most probably played a key role in fertilising microscopic algae of the Southern Ocean, emphasising its role as a CO2 sink. These microorganisms grow uptaking the CO2 found in the atmosphere and when they die they sink releasing carbon into the depths of the ocean.”
    Only some do. Most simply become part of the oceanic food chain. How much of a carbon sink even the ones that sink to the ocean floor are is debatable, since some of that would wind up being outgassed. The real carbon sink, as with green growth on land, lies in the period where biomass is increasing. Once that plateaus, though, there is no more sink effect, merely recycling.

  51. Crispin in Waterloo says:

    Several posters above have mentioned a claim that the iron fertilisation experiments (one done in the 80’s that I recall) were ‘failures’. Well it depends on what you are looking for as a success. If the test is of the basic idea that iron-limited growth can be corrected/enhanced by adding iron, it is a spectacular success each and every time it is tried.

    It is interesting to see the Greenie reaction to the first test which I think was about 1983 or 4 – can’t remember exactly. At that time a few tons of powdered iron was spread over a small patch of ocean. The CO2 absorbed over the next couple of days was huge – more than expected. The iron:CO2 ratio was huge.

    The Greenie reaction was apoplectic and a campaign mounted to oppose the use of such a simple and cheap techinque. The reason? “It will mean that people will think they can continue polluting the air by burning coal.”

    If that is not clear enough, let me explain. They said that coal combustion causes ‘pollution’ which in those days meant mercury and lead and uranium and ash raining down from ther sky downwind of coal fired generating plants without emission (dust) capture equipment installed. Real environmentalists had by then created an awareness of emissions from coal stations and were referring to the continuation of those emissions being made possible by the removable of CO2 from the atmosphere in an easy and cheap manner.

    In the subsequent decades the term ‘pollution’ morphed into CO2 itself being a type of pollution. Witness the current directive to the EPA. So the Greenies know full well the implications of a simple, cheap and easy way to promote the uptake of CO2 by the ocean. All ships passing through the region can spray out a mist of iron oxide – say, ground-up old ships. Now, what is the current ‘Team’ response to this? It is to attack at every possible opportunity any plan to proceed with it. This includes the creation of apocalyptic chemistry scenarios which will turn the whole ocean into [insert armeggedon scene of choice] so no research should be allowed.

    Compare the cost of CO2 capture and storage with ocean fertilization. The article above still makes its case on the basis that CO2 regulates global temperature, something far from being convincingly proven. It still appears that CO2 is a laggard not a leader.

  52. Scott Covert says:

    How does this junk get through peer review? Didn’t someone bother to demand some sort of evidence supporting causation? At least it’s falsifiable, it might be a good High School science fair project to pick this study apart and falsify it. You might even get a guest post here, that would look good on a college application for a physics major.

  53. pat says:

    So we see huge annual fluctuations in atmospheric CO2, right? Oh wait, we don’t.

  54. Grey lensman says:

    The correct form of iron employed to seed oceans is Iron Sulphate

  55. Speaking of dust… I do recall an Asian dust storm crossing the Pacific to North America and receiving a flight advisory to that affect. And coincidental, flying on through it. It was quite hazy. I also recall how unbearable the winter was after Pinatubo. No CO2 warnings, or advisory.

    Now my question. Was that event after Pinatubo or before? Was the dust due to a cold dry Asia winter following the eruption, followed by a strong dry summer easterly wind? Is there more dust when it is colder?

    By the way, where do the crazies get the idea to seed oceans with Fe? The price of steel is already high. We need CO2 for our sodas!

  56. John Kehr says:

    Sorry, but this fails the cause and effect test.

    The differing climates (glacial/interglacial) of the past result in differing levels of global deserts. Much like the temperature of the oceans determines the atmospheric CO2 levels, the amount of global desert determines the amount of dust in the atmosphere.

    Glacial periods cause extensive desert conditions in Africa and Australia. This in turn causes higher levels of dust which cause an increase in the iron flux to the oceans. It has been shown that iron levels do cause large plankton blooms, but fail to have significant CO2 impacts (not that CO2 matters anyway).

    If the Milankovitch cycles cause the glacial / interglacial cycles, then the iron flux would be identical to the results of this paper. Much like CO2. Unless it can be shown that iron flux initiates the glacial/interglacial cycle INDEPENDENT of solar insolation, this is simply another side effect of the Milankovitch cycle.

    http://theinconvenientskeptic.com/2010/10/geo-engineering-more-about-bad-ideas-to-save-the-earth/

  57. phlogiston says:

    John Kehr says:
    September 2, 2011 at 2:45 pm
    Sorry, but this fails the cause and effect test.

    I agree. The paper fails to show causation from the dust, just correlation. However it is known from the Devonian and Carboniferous that increased plant activity can cause global CO2 to decrease. There is a feedback response from plants – in the Devonian they evolved larger and more efficient leaves, sucking up CO2 even more efficiently [1]. Possibly the recent evolution of the C4 photosynthesis in monocot grasses, which fixed CO2 more efficiently, might be a response to falling CO2 levels.

    Africa, where humans evolved, has been subject in the last few million years to large alternations in the dominant vegetation from forest to grasses, back and forth. Grass dominated periods I think coincided with glaciations and colder periods, with (possibly) less CO2.

    In any case, levels of CO2 below 200 ppm are dangerously low for the green plant based ecosystem on earth. This is a fact lurking uneasily in the background of this study, so the AGW climate community will be well advised to handle it with care.

    Plants on earth are a significant factor in climate, not only due to the gas exchange role and CO2, but also for creation and maintenance of soils (humic weathered silicates) which retain moisture on land, but also for the transpiration which drives the hydrological cycle and promotes rain far from coastlines (in Spain falling mainly on the plain etc.)

    Thus it is even possible that excessively low CO2 could impact climate through a detrimental effect on global plant metabolism and resultant disruption of the hydrological cycle.

    This graphic (ignore the irrelevant coloured lines) shows clearly that present CO2 levels are near to the low, not the high, end of the range of atmospheric CO2 levels that are favourable to life on earth.

    http://img801.imageshack.us/img801/289/logwarmingpaleoclimate.png

    Ref. 1: Beerling and Berner 2005, http://www.pnas.org/content/102/5/1302.full.pdf

  58. Robertvdl says:

    phlogiston says:
    “Levels of CO2 below 200 ppm are dangerously low for the green plant based ecosystem on earth”

    So that is why there was more dust at the end of the ice-ages . Less CO2 = less plants on land = more dust
    http://upload.wikimedia.org/wikipedia/commons/c/c2/Vostok-ice-core-petit.png

  59. phlogiston says:

    Robertvdl says:
    September 3, 2011 at 3:14 am
    phlogiston says:
    “Levels of CO2 below 200 ppm are dangerously low for the green plant based ecosystem on earth”

    So that is why there was more dust at the end of the ice-ages . Less CO2 = less plants on land = more dust
    http://upload.wikimedia.org/wikipedia/commons/c/c2/Vostok-ice-core-petit.png

    Interesting possibility.

  60. G. Karst says:

    Isn’t some 30,000 metric tons of extraterrestrial dust fall to Earth each year, mixing unobtrusively with the home-grown grime collecting on all surfaces great and small? Some excerpts gathered from http://www.thefreelibrary.com pages.

    interplanetary medium – interplanetary space including forms of energy and gas and dust affects Earth gained prominence after a pair of scientists hypothesized that waves of space particles triggered the last 10 ice ages (SN: 10/4/97, p. 220). That possibility was raised by Richard A. Muller Richard A. Muller (January 6 1944 -) of San Francisco, California, U.S., is a physicist who works at the University of California, Berkeley and Lawrence Berkeley National Laboratory.

    In Muller and MacDonald’s model, the amount of dust reaching Earth rises and falls as the plane of Earth’s orbit tilts up and down through the plane of the solar system solar system, the sun and the surrounding planets, natural satellites, dwarf planets, asteroids, meteoroids, and comets that are bound by its gravity. The sun is by far the most massive part of the solar system, containing almost 99.9% of the system’s total mass.

    This orbital bobbing, they surmised, would cause the planet to pass through a thin band of dust every 100,000 years–a period that matches the ice age cycle. Every 100,000 years or so, the planet’s temperature plummets, then rises in short thaws like the one that has graced the climate for the last 10,000 years.

    Kortenkamp and Dermott tested this hypothesis by creating a model that computes the path of dust leaving the asteroid belt and falling toward the sun. Such debris accounts for perhaps three-quarters of the interplanetary dust that reaches Earth; the rest comes from comets, say the researchers.

    Over a period of 100,000 years, Earth’s orbit gradually shifts from a nearly perfect circle to a slight oval and back again. In the circular orbit the planet travels more slowly through the dust cloud and therefore sweeps up two to three times as much debris as it does in the oval orbit, according to the model. Kortenkamp compares this to a vacuum cleaner’s picking up more dirt when pushed slowly over a carpet.

    Records of extraterrestrial dust gleaned from seafloor sediments confirm the model results in part, says Kenneth A. Farley of the California Institute of Technology California Institute of Technology, at Pasadena, Calif. Like the model, the sediments show dust increasing by a factor of 3 every 100,000 years. The problem lies in the timing. The sediments contain more dust when the model predicts that accumulations should be declining. “Something is really peculiar here,” says Farley.

    Climate researchers are skeptical that a tripling of dust accumulation triggered the ice ages. Kortenkamp and Dermott leave that question aside but speculate that the amount of dust could rise to more than 300 times modern values following major collisions in the asteroid belt. Persisting for a million years or more, these dust storms could disrupt climate and bring about long periods of extinctions. Such collisions would also eject larger chunks, which could wallop Earth in the wake of the dust waves.

    Models – go figure GK

  61. nimbunje says:

    As a teenagers we were taken just outside Wagga Wagga Australia by our school in 1976 to view a layer of wind blown soil in a gully 9 feet thick called the Brucedale layer .It was deposited during the last ice age by winds blowing from Central Australia S/E towards the Southern Ocean .The iron composition of a lot of Australian Desert soils is well known, and any Australian who has lived through a major dust storm will attest to the density such storms achieve .In a drying and fluctuating climate such as the onset of an ice age such storms would be expected to worsen and become more common ,hence more iron deposition in the Southern Ocean .

  62. RoHa says:

    During the Second World War both the North Atlantic and the Eastern Pacific got a fair amount of iron (in the form of steel-hulled ships) dumped into them. What effect did that have?

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