Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Biotech Science

Reduce CO2 With Phytoplankton Seeding 54

Posted by timothy from the chain-of-events dept.
JediJeremy writes "Nature has this article on a team of scientists who want to reduce the amount of CO2 in the atmosphere by increasing the amount of phytoplankton in the oceans. Phytoplankton thrive on iron, so the scientists are going to conduct a study to better grap the affect of an increase of iron in the water will be. They plan to dissolve an iron sulphate solution in a 150-200 square-kilometer patch of the Southern Ocean, near Antarctica to maximize the containment of the iron. The major flaw in the plan is it will only work if the phytoplankton die and sink to the bottom of the ocean, taking the CO2 with them, otherwise, the carbon will be reintroduced into the ecosystem. Interesting idea, but big design flaw."
This discussion has been archived. No new comments can be posted.

Reduce CO2 With Phytoplankton Seeding More

Reduce CO2 With Phytoplankton Seeding

Comments Filter:
  • Unless there's some kind of magic alchemy going on, there isn't any more carbon on Earth now than there was a billion years ago. Not much of a design flaw in that respect.

    But at the very least it would be putting it go good use: Plankton feeds fish, humans eat fish. Can't be all bad...

    On the other hand, you could conceivably harvest the plankton and turn it into fuel of some kind, or stuff it in an abandoned mine like they're trying to do with gaseous CO2 already.
    =SMidge=

    • Re:Design flaw? (Score:4, Informative)

      by Radical Rad ( 138892 ) on Monday January 26, 2004 @08:54PM (#8095665) Homepage
      or stuff it in an abandoned mine like they're trying to do with gaseous CO2 already.

      I haven't heard about plans to store it in a mine. I have heard several times about sinking it to the bottom of the ocean. That seems like a bad idea to me though. What if something disturbed the ocean like an asteroid strike or nuclear blast? If a lot of CO2 came to the surface at once (in addition to the methane currently locked in ice) it could asphyxiate millions depending on how much was released. Similar things happen frequently in volcanic regions. A CO2 eruption in Camaroon in 1986 killed thousands of people and animals. http://www.geology.sdsu.edu/how_volcanoes_work/Nyo s.html [sdsu.edu]

      • Re:Design flaw? (Score:5, Informative)

        by Smidge204 ( 605297 ) on Monday January 26, 2004 @09:33PM (#8096059) Journal
        If you have asteroid strikes reaching the bottom of the oceans or nuclear blasts in just about any form, CO2 probably ain't your biggest problem.

        Here's a reference to the abandoned mine storage [abc.net.au] concept.
        =Smidge=

      • I didn't hear about mines, I thought it was... (Score:5, Interesting)

        by Tau Zero ( 75868 ) on Monday January 26, 2004 @11:02PM (#8096690) Journal
        ... exhausted oil and gas wells and other deep aquifers. These have the known geological stability to be able to hold gases for aeons, and a great many of them have pipes running into them already.

        The previous responder's link [abc.net.au] identifies "abandoned mine shafts" as one of the several possibilities, but I suppose those mines would have to be very deep and have few fractures, else the CO2 would leak right out again.

        FWIW, one of the advantages of using "spent" oil wells is that you can't recover all of the oil just by pumping. CO2 is a nice non-polar solvent and it dissolves the remaining oil stuck in the pores of the rock, so you can circulate it and boil off the CO2 from the stuff you bring back up, leaving oil as the bottoms. This might not be economical to do for its own sake, but if you are already paying for the CO2 disposal the oil recovery would be icing on the cake.

        • It doesn't matter how leaky the mine is, because CO2 is heavier than air: It just sinks lower into the cracks.
            1. If the area is dry, there is nothing to keep the CO2 from just seeping up through the soil.
            2. If the area is wet, there is nothing to keep the CO2 from dissolving in the groundwater and percolating to a place where it can seep up through the soil, seep into springs or streams where it can bubble off, etc.

            That said, I've read that there have been enough experiments with the pumping of "sour gas" (containing H2S) into deep disposal without any obvious leaks (and they WOULD be obvious) that we can be certain t

      • Re:Design flaw? (Score:3, Informative)

        by SEWilco ( 27983 )
        The ocean bottom already has much more carbon than we might add to it. That carbon is recycled through volcanoes and methane/oil deposits when an ocean plate is subducted and melts.

        Look up "carbon budget" to find estimates of where the planet's carbon goes. However, that is also a Kyoto Protocol phrase so you'll have to add planet-related phrases to reduce noise.

    • Re:Design flaw? (Score:5, Informative)

      by El ( 94934 ) on Monday January 26, 2004 @09:20PM (#8095945)
      Actually, there is slightly more carbon on Earth than a billion years ago due to meteorite strikes, but the important thing is how much carbon is loose in the atmosphere (C02) versus how much is tied up in the crust of the Earth itself or in other forms. Lately we have been decreasing the biomass tied up in trees (thus releasing carbon into the atmosphere), and extracting and burning hydrocarbons like they are going our of style (which in fact they are). The burning of fossil fuel has a secondary affect noone talks about -- sulpher emissions forms sulphuric acid, which then rain down on limestone and erode it at a much faster rate, thus releasing even more carbon dioxide into the air. If all the photoplankton falls to the bottom of the ocean, it'll eventually form new limestone deposits, no? Perhaps it would be more effective to prevent the limestone we have now from eroding. Ok, who's going to help me spray the Himalayas with a protective sealant?
      • I guess the increased acidic rain, not only causing your local water supply to become more toxic (increased heavy metal content (like copper, which is toxic and mercury etc..), an article recently on the BBC's web site stated that the oceans are getting more acidic....okay, I guess that's going to really screw up the planet and make the earth uninhabital...and most of the twits in power are fussing about WMD?
      • Uh... The Himalayas caused global cooling [rochester.edu] which reduced temperatures from the time of the dinosaurs to our present chilled condition. You think the Himalayas are carbonate, but actually they are silicate. Silicate weathering is removing a huge amount of carbon dioxide from the air. If ya seal them mountains y'all will warm up. If you want to cool the planet more, nuke the hills and fracture a lot more rock.
    • "The major flaw in the plan is it will only work if the phytoplankton die and sink to the bottom of the ocean, taking the CO2 with them, otherwise, the carbon will be reintroduced into the ecosystem. Interesting idea, but big design flaw."

      Phytoplankton don"t store CO2, they convert it to carbohydrates and oxygen. Plankton and algae are reponsible for 90 percnt of the oxygen in the earth's atmosphere. Where is the design flaw?

  • Earth to Scientists.... (Score:3, Funny)

    by Anonymous Coward on Monday January 26, 2004 @08:45PM (#8095551)
    Dear Human Infestation,

    Due to your short lifespans and typically self-centered insights, you may not have noticed that I've been decreasing CO2 levels through 'carbon sequestration,' as you call it, for many many millions of years. You may also note that grasses have evolved to take advantage of this. I can only assume you didn't catch the GNN broadcast notifying the rest of the galaxy of my on-going change from forest to steppe.

    Please refrain from terraforming efforts until you have at least the vaguest idea of what you are doing. Thank you for your attention.

    Scincerly,

    The Management.
    • Well, according to some carbon budget calculations we'll run out of carbon in a few hundred thousand years. Without carbon dioxide in the air, all plants will die. Followed shortly by oxygen-using life forms. I hate when that happens.

      Of course, this is a very short time in geologic time scales. Seems unlikely that it would happen now for the first time. This suggests something wrong in such a carbon budget, such as a missing carbon source or overestimated sink. The ocean bottom is one large sink for

        • Well, according to some carbon budget calculations we'll run out of carbon in a few hundred thousand years. Without carbon dioxide in the air, all plants will die. Followed shortly by oxygen-using life forms. I hate when that happens.

        Without carbon dioxide in the air, plants start to die, then decompose/rot/burn, and suddenly we'll have loads of carbon dioxide in the air...

        Unless you can figure out a way to kill all plants pretty much simultaneusly with lack of carbon dioxide, I don't see running out of

        • Nice teamwork of scientist... One scientist does the calculation of "how much carbon we have left". The next scientists announces this in some meeting and adds that "all the plants will die without the carbon dioxide" while the original scientist cringes in hte back corner thinking... 'Plants contain carbon... if we are out of carbon, we are out of plants already.'
        • If you've ever had a compost heap, you'd know that methane is what tends to be generated by rotting, and that a lot of carbon remains in the resulting black compost. (yes, methane also contains carbon)

          ...and burning will be reduced if the oxygen level is indeed reduced.

          Perhaps you confused carbon dioxide from fermentation with rotting.
          Drink beer and save the world!

          However, I did say "some". Feel free to select from the various estimates. The planet does what it does whether we understand it or not.

          • Well, by rotting yes, scratch that over from my previous post, my bad.

            But normal decomposing produces a lot of carbon dioxide. Only if there's a lack of oxygen you get significant amounts of methane. If a compost produces a lot of methane, it's not properly maintained. You don't want things to rot in a compost, you want them to decompose.

  • To REALLY decrease the CO2... (Score:5, Funny)

    by Ugmo ( 36922 ) on Monday January 26, 2004 @08:58PM (#8095720)
    ...they should combine this 'seeding the ocean with iron' with eliminating SUV's.

    This is how you do it: You build giant wood chippers with the ejection shoots aimed out over the ocean.

    Then line up all the SUV's in the USA and make people drive them into the chippers.

    The steel from the SUV's will shoot out and fertilize the plankton.

    To be humane you can let the drivers jump out at the last minute. Unless they're too busy talking on their cell phones to jump.

    Hey, I'm sure the plankton could do with elements other than iron for fertilizer. ;)
    • How much iron is there in one of the new SUVs? Aren't they all made out of used beer cans (i.e. aluminum) and plastic (i.e. hydrocarbons) now?
      • Uh.. If you're trying to drop carbon on the ocean bottom you don't think dropping hydrocarbons would help?
        It just won't affect the plants which are the intended goal of the project.

        And the carbon emissions of SUVs are limited by their high price and the higher cost of fueling a low-MPG SUV (15-20 city MPG SUV [edmunds.com], 20-30 city MPG sedan [edmunds.com] [Should the 40 city MPG Ford Escape SUV be included or not? Show your work.]).

  • Smetacek and 48 colleagues... will monitor the growth of phytoplankton from a helicopter...for a period of eight to ten weeks.

    (49 scientists + boat + chopper) * 10 weeks = enough CO2 to give all these newly spawned (hatched? divided?) planktons serious eating disorders.

    Why do you have to come down here and tip all that FeSO4 in my backyard? What, Baltic wasn't big enough? Too shallow? No happy snaps with penguins?

  • Carbon Cycle in National Geographic (Score:3, Informative)

    by eht ( 8912 ) on Monday January 26, 2004 @10:34PM (#8096501)
    National Geographic just did an article about the Carbon Cycle [nationalgeographic.com] in their February issue. They stated that this has been tried, but it's been found that most phytoplakton die and decay on the surface without falling to the ocean bottom.
    • Unfortunately, your link does not take one to the entire article.

      I recall that one such iron-seeding experiment was done in the tropics. One would almost expect the results to be different in the arctic, because cold arctic waters are where the coldest deep-ocean water is formed. If that water is sinking, it seems likely that it would tend to take dead algae with it. (On the other hand, the fact that many Antarctic waters are relatively fertile suggests that there are upwelling currents there which account

  • stop breathing ^_^

    Have a nice day!
  • The theory was tested by some scientists near the antarctic and while it worked a little the cost of actually doing it is prohibitive. This does not take into account the affect creating billions more of the wee beasites would have on the marine life cycly. Hell the person who first discovered the photopankton advised against this method of using them because of the way negative effects it could have (like feeding alge growth that kills fish). Check out the latest issues of Discover and Scientific Amerian f

  • Old theory on a new scale (Score:3, Informative)

    by (0d0 ( 633681 ) on Tuesday January 27, 2004 @01:49AM (#8097469) Journal
    This has been looked at before (as stated in the article) but only on a much smaller scale. The difference with this project is that they intend to cover a larger area and to watch it for a longer period of time. However, a couple of months will not be long enough to truly judge what sort of side-effects this method may generate.

    There is the question of whether the phytoplankton will fall to the ocean bottom and actually remove the CO2 from the system, but this is really less of an issue, I think, because there are many "outs" that the carbon can take to actually fall to the ocean floor. At every step in the food chain things die and float to the bottom or are consumed and excreted and float to the bottom. the general theory is that X% of the biomass will always fall to the ocean floor. If you increase the biomass by a factor of Y, you should see a y-fold increase in flocculation of carbon.

    Other questions to consider are what will the effect of an iron enrichment be to other life forms in the same waters? Will the FeSO4 level be toxic to zooplankton or to certain species of fish? Without careful consideration, this process could have devastating effects.

    Fortunately, they are practicing good science in that they are testing their theories on (relatively) small scales before beginning a full regimen of iron enrichment to combat a growing problem. This will not solve our problems by any means. It is merely to stem the tide so that better environmental practices can be realized.
    • ...to stem the tide...

      I sure hope that wasn't intentional. Ick.

    • You're worried if the FeSO4 level might be toxic to zooplankton or fish? In this situation that might be good. More dead zooplankton and fish are more dead things to sink to the ocean bottom, and fewer predators to consume the phytoplankton. If the phytoplankton grow until they die of crowding and sink, that is also OK.

      I don't know if phytoplankton require iron when not growing, or if mature phytoplankton can exist indefinitely with the iron locked within their system. Do they leak iron and eventually

  • "Easy" global solution? (Score:4, Interesting)

    by Urkki ( 668283 ) on Tuesday January 27, 2004 @03:27AM (#8097806)
    I wonder what's wrong this idea:

    1. Grow trees, grass and stuff
    2. Cut the grown trees, grass and stuff
    3. Bury the cut down trees grass and stuff

    Keep doing this at same scale as we use fossil fuels, and make oil companies to pay for it (and add it to the price of fossil fuels). For extra value, turn trees into paper, use it, then bury the scrap paper.

    Now there must be something seriously wrong with this, since I haven't seen this suggested anywhere. Is it sheer scale, us using far more fossil fuels than we can practically grow and harvest plants for burial?
    • Problem 1: Shallow burial is a very short-term carbon sink. As soon as the buried biomass decomposes, its constituent elements will be released back into the system.

      Plankton can be a long-term sink. If a sufficient portion of them do sink to the sea bottom, the carbon can stay out of the system for a geologically significant period.

      Problem 2: Speed. Even with optimum fertilization, only so many plants can grow on one acre of land in a year.

      Plankton aren't as limited because they live in a three-dimension
      • I've attended talks at the Land Institute [landinstitute.org] about using restored prairie as a carbon sink. Apparently the native prairies in North America were awesome carbon sinks due to the deep root structures that the plants had. Modern crops have much shallower roots and therefore can't pull as much out of the atmosphere.

  • Just like in the books (Score:3, Interesting)

    by kippy ( 416183 ) on Tuesday January 27, 2004 @11:09AM (#8100359)
    This was done almost step for step in one of the Red Mars trilogy [amazon.com] by Kim Stanley Robinson. I think it was in either Green Mars or Blue Mars but folks back on Earth were dumping iron dust into the ocean off of Antarctica to boost the plankton population to act as carbon fixers. He presented it basicaly as terraforming on Earth.
  • Wired ran an article [wired.com] in 2000 about other groups who were using the same method to the same purpose. It's quite a bit longer and more detailed, giving a more complete picture of how it's intended to work.
  • If critters eat the phtyoplankton then they carry the CO2 and keep some it circulating within the ecosystem. More critters that live and eat the phytoplankton and critters that eat the phytoplankton increase the holding capacity of the CO2.

    Yes, some will be released back but the critters become CO2 holding containers. The more biomass of critters available, the more can be held.

    Waste, detritus and dead critters that fall to the bottom of the ocean will carry some CO2 to the depths but the key is to incr
  • Why cann't those plants convert CO2 to O2 + C?

    What is wrong with this plan? Just grow a lot of plants or the same plankton and we'll have no CO2 problem.
    • You just described the plan. The test area is a part of the ocean which is low on iron, thus phytoplankton (tiny ocean plants) can not grow well there. By adding iron, many of those tiny plants will grow. (It has been suggested that during an ice age, the dry air causes more iron-containing dust to reach oceans thus the ice causes more cooling due to carbon dioxide being removed)

      What is wrong with this plan? That is what is being studied. We don't know if the plan will work nor in what ways it can fa

      • Well, as *I* see the plan from the comments here, the plan is to take the carbon out of circulation by making plankton accomulate carbon by converting CO2 to C+O2 and then make the plankton sink to the bottom of the sea.
        What I don't understand is the second part of the plan, what is the sence in that?

Slashdot Top Deals

Ocean: A body of water occupying about two-thirds of a world made for man -- who has no gills. -- Ambrose Bierce

Close