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

 



Forgot your password?
typodupeerror
×
Earth Science

Plan to Slow Global Warming By Dumping Iron Sulphate into Oceans 407

ananyo writes "In the search for methods of geoengineering to limit global warming, it seems that stimulating the growth of algae in the oceans might be an efficient way of removing excess carbon dioxide from the atmosphere after all. Despite attracting controversy and a UN moratorium, as well as previous studies suggesting that this approach was ineffective, a recent analysis of an ocean-fertilization experiment eight years ago in the Southern Ocean indicates that encouraging algal blooms to grow can soak up carbon that is then deposited in the deep ocean as the algae die. Each atom of added iron pulled at least 13,000 atoms of carbon out of the atmosphere by encouraging algal growth which, through photosynthesis, captures carbon. The team reports that much of the captured carbon was transported to the deep ocean, where it will remain sequestered for centuries — a 'carbon sink' (abstract)."
This discussion has been archived. No new comments can be posted.

Plan to Slow Global Warming By Dumping Iron Sulphate into Oceans

Comments Filter:
  • Ending badly? (Score:5, Insightful)

    by eisonlyme ( 1877576 ) on Thursday July 19, 2012 @11:39PM (#40707689)
    I always worry about these ideas, they seem good in theory, but in reality you can just end up with a cane toad problem..i.e. when the algae has covered all the oceans we have no pollution...but also no fish....
    anywho...maybe we can just set fire to the algae if it gets out of control...
    • Re: (Score:2, Funny)

      by Anonymous Coward

      No, what we need is gorillas. They'll kill the snakes, then die off in the Winter.

      Problem solved.

    • Re:Ending badly? (Score:5, Interesting)

      by ShanghaiBill ( 739463 ) on Thursday July 19, 2012 @11:50PM (#40707759)

      .. maybe we can just set fire to the algae if it gets out of control...

      Or we can try this on a trial basis, and scale it up if it seems to be working. When the algae sinks, carrying the carbon to the bottom of the ocean, it takes the iron with it. So when we stop putting the iron in, the amount of algae returns to normal, so it is unlikely to "get out of control." Sure, there might be some side effects, but there will probably be even bigger side effects if we do nothing. And the side effects are not all bad: it should increase the amount of fish that can be sustainably harvested.

      • Re:Ending badly? (Score:4, Insightful)

        by phantomfive ( 622387 ) on Friday July 20, 2012 @12:08AM (#40707859) Journal

        And the side effects are not all bad: it should increase the amount of fish that can be sustainably harvested.

        Indeed, it could overall be a GOOD thing for the overall biosphere.

        As you said, I'd suggest trying it in a small region first, and if no negatives are found, try it in a slightly larger area.

      • Re:Ending badly? (Score:5, Informative)

        by Anonymous Coward on Friday July 20, 2012 @12:16AM (#40707917)

        And the side effects are not all bad: it should increase the amount of fish that can be sustainably harvested.

        The 2 side effects mentioned in the article both kill fish. Toxic algal blooms poison fish, either causing them to grow abnormally or death. Depleted oxygen levels does the same thing to the fish as it does to you, suffocation.

        • In many places of the world, nutrient-rich deep-ocean water rising to the surface causes natural algal blooms. Algae eating fish like sardines flock to them and breed up in huge numbers, and form the basis for many of the world's fisheries.
          Indeed, practically all fish either eat algae, or eat marine life that eats algae.
          So fertilising the oceans is just as likely to produce schools of fish and new rich fisheries to harvest as fish kills. In reality, it would probably cause both: overpopulation of fish that

      • Or we can try this on a trial basis, and scale it up if it seems to be working. When the algae sinks, carrying the carbon to the bottom of the ocean, it takes the iron with it.

        Well, it's not that simple. The algae we cause to bloom consumes nutrients that would have been consumed by other algaes. Nor is the ocean bottom dead - dumping that massive amounts of iron and algae into them is not going to be without effect.

    • Re:Ending badly? (Score:5, Interesting)

      by aXis100 ( 690904 ) on Thursday July 19, 2012 @11:55PM (#40707783)

      It's not a new thing - iron dust has been blowing into the oceans for millenia.

      Recent urban development around our coastlines have significantly reduced this natural nutrient source, so projects like this are really just restoring balance.

    • Re:Ending badly? (Score:5, Insightful)

      by Black Parrot ( 19622 ) on Thursday July 19, 2012 @11:55PM (#40707785)

      I always worry about these ideas, they seem good in theory, but in reality you can just end up with a cane toad problem..i.e. when the algae has covered all the oceans we have no pollution...but also no fish....

      anywho...maybe we can just set fire to the algae if it gets out of control...

      The underlying problem is, people are willing to consider anything - except addressing the cause of the problem.

      • Re:Ending badly? (Score:5, Interesting)

        by phantomfive ( 622387 ) on Friday July 20, 2012 @12:14AM (#40707901) Journal

        The underlying problem is, people are willing to consider anything - except addressing the cause of the problem.

        The underlying problem is too hard to solve with current technology. According to Hansen et al, we need to get the CO2 levels down to 350ppm if we want to be safe. This means, not only must we immediately stop adding CO2 to the atmosphere, we also need to remove some of it.

        So think of all the things you do that add CO2 to the atmosphere (of course breathing doesn't count because it is net neutral). That is pretty near everything. Imagine if we stopped all that immediately. Not only would we have to switch over to nuclear, we'd also have to stop driving. And flying. Good luck at that, it would be economic suicide.

        No one is willing to do that, so the only proposals are things like Kyoto, which did little, or Copenhagen, which would have done nothing.

        • "No one is willing to do that, so the only proposals are things like Kyoto, which did little, or Copenhagen, which would have done nothing."

          It's not that they're UNWILLING to do that, at all. It's that it would be so enormously expensive, they want SOLID proof before going down that road. Evidence that has so far not been forthcoming.

          Seriously: the cost of sequestering enough carbon dioxide to prevent 0.5 degree C warming over the next hundred years, has been estimated to be about the same as the cost of completely eliminating world hunger, even after considering inflation.

          Which is the better investment?

          I'm not saying that it's not a g

        • The underlying problem is too hard to solve with current political will. Nobody is suggesting we change everything overnight but considering we burn 5 billion tons of coal/yr and that every fuctioning coal plant on the planet has been built (and in many cases rebuilt) since I was born, 50yrs is plenty of time to convert to renewables. If it wasn't for vested interests this would happen in a similar way to how the current FF infrastructure was built (hardly noticable to the casual observer). If you want more
        • Re:Ending badly? (Score:5, Interesting)

          by khipu ( 2511498 ) on Friday July 20, 2012 @01:46AM (#40708409)

          The underlying problem is too hard to solve with current technology. According to Hansen et al, we need to get the CO2 levels down to 350ppm if we want to be safe. This means, not only must we immediately stop adding CO2 to the atmosphere, we also need to remove some of it.

          Hansen is someone who spreads FUD to gain notoriety. Read the IPCC instead. It contains a lot of scary imagery too, but ultimately, you can find a simple cost/benefit analysis, which sums it up:

          http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains5-7.html [www.ipcc.ch]

          For increases in global average temperature of less than 1 to 3ÂC above 1980-1999 levels, some impacts are projected to produce market benefits in some places and sectors while, at the same time, imposing costs in other places and sectors. Global mean losses could be 1 to 5% of GDP for 4ÂC of warming, but regional losses could be substantially higher.

          Limited and early analytical results from integrated analyses of the global costs and benefits of mitigation indicate that these are broadly comparable in magnitude, but do not as yet permit an unambiguous determination of an emissions pathway or stabilisation level where benefits exceed costs.

          The idea that we should dump vast quantities of iron into the ocean in order to mitigate a potential problem that amounts to little more a slight reduction in global GDP is ludicrous. Algal blooms and tinkering with iron content of the ocean is far more dangerous than rising CO2 levels, Hansen's cataclysmic fantasies notwithstanding.

          • This. The falling sky proponents love to pretend that it's all a done deal yet the entire model fails to adequately account for previous warm periods, nor the fact that CO2 is merely plant food. (photosynthesis, how does it work?)

            Even if you accept the premises that 1) the climate is warming and 2) that human produced CO2 is to blame, taking the entire thing a step farther to say that we can effectively mitigate the problem by radical geoengineering means is a step way beyond credibility. That we SHOULD d

            • Re:Ending badly? (Score:4, Insightful)

              by zolltron ( 863074 ) on Friday July 20, 2012 @09:39AM (#40712035)

              This. The falling sky proponents love to pretend that it's all a done deal yet the entire model fails to adequately account for previous warm periods, nor the fact that CO2 is merely plant food. (photosynthesis, how does it work?)

              Even if you accept the premises that 1) the climate is warming and 2) that human produced CO2 is to blame, taking the entire thing a step farther to say that we can effectively mitigate the problem by radical geoengineering means is a step way beyond credibility. That we SHOULD do such a thing is absurd in the extreme.

              The law of unintended consequences patiently waits.

              You think it's a bad idea to seed the oceans with iron, because our interfering with the natural ecosystem might have unintended consequences. So instead, you're suggesting that we should do nothing to stop our interfering with the natural ecosystem by pumping huge amounts of CO2 into the air.

              Seems consistent.

            • by tgibbs ( 83782 )

              The falling sky proponents love to pretend that it's all a done deal yet the entire model fails to adequately account for previous warm periods, nor the fact that CO2 is merely plant food. (photosynthesis, how does it work?)

              In fact, modern climate theory quite well account for climate over the period for which we have reliable information on both global temperature and drivers of climate such as solar radiation and CO2, including the impact of "natural experiments" such as volcanic eruptions. Estimating cli

        • What they've said is "We shouldn't have done this." Ok, fair enough, nothing wrong with that but that isn't a solution. Telling someone that what they did to cause a problem shouldn't have been done is all well and good, but doesn't solve the problem, it isn't really that useful.

          It would be like going to the doctor because you'd broken your arm and having him say "Well you really shouldn't have fallen off your bike, had you not done that, your bone wouldn't be broken. You shouldn't ride your bike at all in

      • Fundamentally nobody is willing to do what it takes to deal with carbon emissions...it's perceived as too expensive.

        On the other hand, geoengineering solutions (if they work) would be cheap. I heard an estimate that a fleet of small autonomous ships spraying seawater into the air (to seed clouds and increase albedo) would cost ~6 billion. That's nothing in comparison....there are individuals that could afford that.

    • Re:Ending badly? (Score:5, Insightful)

      by Anonymous Coward on Thursday July 19, 2012 @11:57PM (#40707791)

      The basic problem I can see is that the ocean is a complex set of currents that moves nutrients around. Dumping a compound into the ocean at one point to encourage algae blooms may sequester carbon in that location but it also locks up other nutrients as well that would have normally travelled to another part of the ocean. Now maybe such an action will disturb the proliferation of jellyfish somewhere but it's more likely that the missing nutrients will simply impede the growth of algae in another location where, instead of simply dying and sequestering carbon at the bottom of the ocean (from which it will eventually bubble up as methane at some future time) the algae would have provided the base of some local food chain. SO, in short, we lock up both carbon and nutrients in some normally unused part of the ocean while starving another part of the ocean for nutrients.

      Yeah, terraforming is an interesting science but it's a risky one when you only have one test case and every bit of life you know of in the universe lives in that single test case.

      But, I did see reports of the earlier test case and the motivation behind it. It wasn't really all about saving the planet as much as it was about creating a measurable amount of carbon credits that had a solid monetary value. That was the real motive, creating a way to manufacture carbon credits for sale. The test was done to see if they could find the ratio of carbon sequestered per ton of iron compound dumped into the ocean. That way they could dump a known amount of iron in the ocean and then sell a calculated amount of carbon credits on the carbon credit exchange.

    • Its no worse an idea than say ocean trawling or deep sea oil drilling.

    • Re:Ending badly? (Score:5, Informative)

      by Jane Q. Public ( 1010737 ) on Friday July 20, 2012 @01:03AM (#40708143)

      "I always worry about these ideas, they seem good in theory, but in reality you can just end up with a cane toad problem..."

      Mod parent up.

      Without any doubt. FAR more study would have to be done, over a LONG period of time, before any direct messing with the ecology should be attempted.

      I live near a lake that was once called, by National Geographic, one of the 12 most beautiful lakes in the world (and it is a rather large lake, as such things go). And there were wonderful fish in the lake; salmonids, plentiful and tasty.

      Local businesses, recognizing that fishing was a major tourist attraction, pressured the state Fish & Wildlife Commission to "improve" the fishery.

      I could go on for a long time. But suffice it to say that they did one thing that was well-intended, and supposed to help the fish population. But it had unintended consequences. Then they fooled with the ecology again, to try to fix their first fuckup, but THAT had unintended consequences. Then they did it AGAIN, to fix that one, and THAT had unintended consequences.

      The long and short of it is: they averted total disaster from their first mistakes, but the fishery is nowhere near as healthy and strong and plentiful as when they first tried to intervene. And yes, it is all directly attributable to their actions.

      BE VERY CAREFUL BEFORE YOU FUCK WITH THE ECOLOGY. THE LAW OF UNINTENDED CONSEQUENCES IS LIKELY TO BITE YOU IN THE ASS.

      We have seen this in so many different ways. These people should have their heads examined if they propose to do it anytime soon. Long-term study is needed, even if things get bad. Anyone who tries it before thorough long-term studies are done is probably deserving of being taken out and shot.

      • I really should have included the time scale: they have been trying to correct their original mistake now for 30 years, and haven't managed to do it.
  • Far-fetched (Score:5, Insightful)

    by LordLucless ( 582312 ) on Thursday July 19, 2012 @11:45PM (#40707727)

    Seems no more far-fetched than the current plan, which is assuming world leaders of developed and developing nations can all agree to limit the economic function and development of their respective countries, and not fall into a prisoner's dilemma.

    • Sad but true.

      Kyoto etc. might have worked if there was a crash research program into viable clean sources of power (eg fusion) and battery tech back in the 90s. As it is, there wasn't, we have no reasonable way of both (1) keeping our lifestyle and (2) meeting Kyoto targets.

      _Something_ has to be done; if the idea in TFA is based on sound science, why not give it a go. Start slow, maybe, but at least try.

      • The sad thing is, even if we'd met Kyoto, it would have made little difference to the overall human CO2 emissions. Kyoto wasn't anywhere near enough to turn things around, and anything more would have caused economic damage.
    • by asa ( 33102 )

      The current plan seems to be "do nothing big enough to stop a massive extinction event, but do lots of little things around the edges that make people feel better while we all slip past the point of no return."

      I'm not enthusiastic about most of the geoengineering ideas floating around today, but I suspect we're going to end up needing some of them. In that light, lots of experiments now to understand as much as we can before we're forced to use one or more of them seems prudent.

      We won't do the right thing.

      • I don't understand this. If you believe that the consequences of AGW are on the scale of catastrophic mass extinction events then you should be very enthusiastic about geoengineering. If the entire species is going to die, I'd be pretty enthusiastic about anything that might help.

        What I guess I'm saying is that there is a disconnect (or at least I perceive one) between the urgency of AGW when it comes to pleas for emissions reductions on the one hand, and the tepid response to these sorts of projects. I do

        • "What I guess I'm saying is that there is a disconnect (or at least I perceive one) between the urgency of AGW when it comes to pleas for emissions reductions on the one hand, and the tepid response to these sorts of projects."

          That's easy to explain: even many of the people who profess that CO2-based climate change is "proven", still don't actyally believe it enough that they want people messing with their environment.

          I have seen this, very widespread, and it is very telling to me.

          • What I meant to say is: they say they believe it, and they preach it, but whenever someone proposes a solution that might mess with their lifestyle they are all "no, no, no".

            That's not just NIMBY, it's "I don't truly believe".
    • by khipu ( 2511498 )

      No "prisoner's dilemma" involved for the politicians: voters in the US and Europe would be tearing their politicians apart over the costs of global warming mitigation. Just look at all the belly-aching over the current recession.

  • Before we have to drop giant blocks of ice in the ocean...

    • Before we have to drop giant blocks of ice in the ocean...

      Done [go.com]. Too soon to see if this one will help. The previous, and larger ones didn't seem to change much.

    • This is genius! Want to team up and cash in selling snowcones in support of project "iceage"? :)

    • "Before we have to drop giant blocks of ice in the ocean..."

      If you mean like asteroids, the amount of energy they added at impact would far surpass the amount they subtracted from their inherent coldness.

  • We could find a way to trigger a super volcano. This would also help to curb global warming.
    We could create a nuclear winter by setting of several giant nuclear weapons over the countries of choice. This would also reverse global warming.
    There are lots of things which we could do, but doesnt mean we should.
    Considering that we do not know the extent of the oceans impact on global weather patterns, we may do well enough to leave them alone until we do.

  • Since everything we do destroys something on the planet, I'm gonna go ahead and call this one right now. Algea blocks sunlight below, kills seabed plants in shallow areas and kills...I dunno, Nemo or something in deep water by lowering the temperature, making automatic frozen fishsticks.
    This did sound like one of the better theories for fixing the problem extremely quickly and cheaply when I heard about it on TV though.
    • by robbak ( 775424 )

      Nemo is a shallow water fish.

      And ice floats, so no frozen deep-water fish. And we desperately need to make the oceans a little cooler - and get the CO2 out of them.

      Don't get me wrong: the only good solution is to stop pouring CO2 into the air. But, given that humanity is too dumb to do that, this seems like the nearest thing to a workable solution I have heard. Do enough of it, and we might get ourselves some oil, but we might have to wait until the 20,000th century.

  • Algae Blooms (Score:5, Insightful)

    by Albinoman ( 584294 ) on Friday July 20, 2012 @12:27AM (#40707967)

    Yes, let's try to create massive worldwide algae blooms, cause the one's were getting already have been fantastic.

  • by SeaFox ( 739806 ) on Friday July 20, 2012 @12:28AM (#40707975)

    The team reports that much of the captured carbon was transported to the deep ocean, where it will remain sequestered for centuries — a 'carbon sink'

    This line reminded me of plans to store radioactive waste in remote areas, keeping us safe from it for centuries.

    Nobody seems to have a lot of faith in those plans I notice.

  • Surfer is eaten alive by sentient algae blob. Story at 11!

  • by SharpFang ( 651121 ) on Friday July 20, 2012 @12:31AM (#40707991) Homepage Journal

    Let's convert carbon dioxide to methane,that's sure to help...
    Excessive growth of algae (influenced by global warming and fertilizers washed down to the sea from farmlands) is a part of the problem, not the solution.

    The problem with algae is that while, true, they convert CO2 to oxygen, they do so, by growing - building their own mass.
    There's only so much of ocean surface where they can grow by absorbing light. The excess algae not receiving enough light die and rot. And they produce methane by rotting.

    I'm pretty sure as greenhouse effect gas, methane is quite a bit stronger than carbon dioxide...

    • I'm pretty sure as greenhouse effect gas, methane is quite a bit stronger than carbon dioxide...

      Parent is right.
      According to wikipedia (because I am feeling a bit lazy,there are plenty of other sources out there).

      For example, on a molecule-for-molecule basis the direct radiative effects of methane is about 72 times stronger than carbon dioxide over a 20 year time frame[13] but it is present in much smaller concentrations so that its total direct radiative effect is smaller, and it has a shorter atmospheric lifetime

      The interesting thing is that after the shorter atmospheric lifetime that they are talking about here. Methane breaks down into CO2 (!) and Water. Which means that Methane is actually a double whammy for global warming.

  • Yep, lock up our atmospheric carbon at the bottom of the oceans where we can't get to it. Wouldn't it be better to find a way to directly capture it from the air (through electrolytic deposition or something) so that it can be used by the impending graphene and carbon nanotube industries?
    • See those mountains of coal that get shovelled into our power stations every day? Can you use that much carbon nanotubes and graphine?

  • The team reports that much of the captured carbon was transported to the deep ocean, where it will remain sequestered for centuries - a 'carbon sink'

    This sounds like a good quick patch (in the ecological time scale), but do we need that carbon? Seems like moving carbon from the Earth's crust to the deep ocean could have some long-term ramifications. I'm not sure I know enough about the subject even to qualify as an amateur, but it seems like it would be more profitable in the long run if we could grow plant

  • by hessian ( 467078 ) on Friday July 20, 2012 @01:31AM (#40708323) Homepage Journal

    Climate change is but one of the problems we face. Pollution, loss of species, erosion and depletion of natural resources are all big problems as well.

    The sad fact is that all of these have a single cause: humans, or rather, too many humans.

    As of right now, the average Chinese person emits as much carbon as the average European [todayonline.com] -- and there are many more Chinese people.

    The rest of the developing world is going to follow this pattern. Soon we'll all be emitting high amounts of carbon, but even more, each of us will require a lot of land for our lifestyles. Not just our homes, but roads, hospitals, shopping, parking, schools, storage, government buildings, etc.

    For every person we put on this earth, there's less space for the natural world and its forests and oceans which renew our air and water. Earth is finite; humans are acting like its capacity to have new humans is infinite.

    We're all in denial of how simple this is. There are too many people. We're making even more. At some point, we will have used up enough land so that pollution, species loss and loss of renewable resources makes us get a Darwin award as a species.

  • Causing an algae bloom is good now?
  • Didn't I just recently hear about the idea to seed iron to fight global warming. Right, it was the Panchaea project [wikia.com] in Deus Ex Human Revolution. Well I just hope it works out better than it did in the game though :P

  • by ddt ( 14627 ) <ddt@davetaylor.name> on Friday July 20, 2012 @03:01AM (#40708697) Homepage

    Seeing as how 1/3 of the earth is made of iron and we've assuredly been rained upon by some iron meteorites that probably popped somewhere in the atmosphere, something tells me that iron-rich moments in the ocean's history have not been unknown. Does the fossil record have anything to say on the subject?

    • by Guppy ( 12314 )

      Seeing as how 1/3 of the earth is made of iron and we've assuredly been rained upon by some iron meteorites that probably popped somewhere in the atmosphere, something tells me that iron-rich moments in the ocean's history have not been unknown. Does the fossil record have anything to say on the subject?

      Banded Iron Formations [wikipedia.org].

  • by fygment ( 444210 ) on Friday July 20, 2012 @06:12AM (#40709543)

    It will be sequestered for centuries ... a nuclear sink.

    Out of curiousity, after centuries, what happens?

  • by stigmerger ( 989244 ) on Friday July 20, 2012 @08:22AM (#40710825)

    Seriously?

    Someone is destroying your entire ecosystem, and telling you "we can't stop doing that, because we would lose money." And someone else says, "well, maybe if we cause a corresponding rapid radical transformation in ocean ecology it will offset the other catastrophe". And your answer is "hmm, yeah, that might work."

If all else fails, lower your standards.

Working...