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Global Warming Stopped By Adding Lime To Sea

Antiglobalism writes "Scientists say they have found a workable way of reducing CO2 levels in the atmosphere by adding lime to seawater. And they think it has the potential to dramatically reverse CO2 accumulation in the atmosphere, reports Cath O'Driscoll in SCI's Chemistry & Industry magazine published today."

20 of 899 comments (clear)

  1. Calcium hydroxide, not the fruit by Reality+Master+201 · · Score: 5, Informative

    You'd think it'd be obvious, but at slashdot, you actually do need to point that out to people.

  2. Re:Anonymouns Coward by jeiler · · Score: 5, Informative

    The process of making lime generates CO2, but adding the lime to seawater absorbs almost twice as much CO2. The overall process is therefore 'carbon negative'.

    RTFA. FTW. My acronyms are more powerful than your anonymity.

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  3. Re:Anonymouns Coward by vidarh · · Score: 5, Informative

    RTFA. The article claims this process sequesters twice as much CO2 as is released during the production of lime.

  4. Re:Ocean of Acid by paazin · · Score: 5, Informative

    And then all these fish die because of too much acid in the water! Epic Fale.

    Uh, not really - Calcium Oxide reduces the acidity of water: Calcium Oxide

  5. Re:Ocean of Acid by wile_e_wonka · · Score: 5, Informative

    This is why we RTFA:

    There are potentially huge environmental benefits from addressing climate change and adding calcium hydroxide to seawater will also mitigate the effects of ocean acidification, so it should have a positive impact on the marine environment.

    Lime is an alkalide.
    Read more here: http://en.wikipedia.org/wiki/Calcium_oxide
    Also here: http://www.cquestrate.com/

  6. I Am A Chemist by PatrickThomson · · Score: 5, Informative

    And this appears to work. I'm sure some not-rtfa'ing people above me will have got in with a quick "making lime generates carbon dioxide hur hur" but the process already takes this into account. By increasing the pH of the seawater, they claim that it will absorb two moles of CO2 for every mole released in the manufacture of lime. I'm not an environmental chemist so I can't comment on the adsorption gradient of seawater, but if they think it'll work then it'll work.

    Carbon dioxide dissolves in water:

    CO2 + H2O H(+) + HCO3(-)

    As does Calcium Oxide (lime)

    CaO + H2O Ca(2+) + 2 * OH(-)

    Hydroxide and protons naturally combine to form water - it's another equilibrium but the constant is something like 10**-7 (that 7 is the pH of water)

    H(+) + OH(-) H2O

    i.e. at pH 7, there will be ten million times as much water as either of the other two.

    I'd imagine that various equilibrium constants shift around to prove that there's a net increase in the absorption of carbon dioxide from air. It's pretty elementary science - so elementary, I've forgotten how to do it. by simply ascribing a token amount of competence to the scientific background of the people in TFA, it can be shown that they probably know what the hell they're talking about.

    Also, there's no doomsday scenario where a drop of lime juice makes the ocean boil pure CO2 and kill us all. As far as I can see.

    --
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    1. Re:I Am A Chemist by Mr.+Underbridge · · Score: 4, Informative

      I'm a chemist too, and read the article, but there were no technical details upon which to judge it. However, I'm pretty leery of screwing with the pH of the ocean, since ecosystems need a pretty stable pH range to thrive. The problems I'd see involve ocean current circulation - namely, how fast can you put the CaO in locally such that it disperses worldwide and generates pH advantages without screwing the pH locally such that it creates ecosystem problems?

      I still have this niggling fear that they're just setting up a feedback loop, because they're not looking at the whole picture. They're making CaO by sticking CO2 into the atmosphere, putting CaO into the ocean, which drops the pH and sucks up some CO2. My thinking is that they've probably used the existing amount of CO2 in the air to determine the rate of CO2 absorption (which they can't do), and that the pH decrease in the rainwater will balance the pH increase of the ocean - which works only until it rains and they re-mix. In other words, when this reaction cycle completes, the pH of the ocean is ultimately the same.

      My intuition is that this won't work, since in the end every mole of CaO they create will ultimately recombine and be re-sequestered as CaCO3 in the ocean. The question is where we want the sequestered CaCO3 - on land or in water? It seems to me if the CaCO3 is in an arid environment as it currently is, that's better than in the ocean where it could actually retard further carbon sequestration through reverse-reaction with acid.

      I give them points for trying, and I don't have enough details to prove it won't work, but I think this is an example best illustrated in the Simpsons, where Homer makes his money by selling grease...that he gets from bacon he cooks...that Marge buys at a higher price.

  7. Re:And finally... by D+Ninja · · Score: 5, Informative

    A solution to nasty-tasting seawater! Lemonade oceans FTW!

    Except...it's lime.

  8. Re:This scares the hell out of me by TMB · · Score: 5, Informative

    > I'll leave out the fact that temperatures globally have been flat for several years now

    Wise move, since it's an incorrect statement.

    http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lrg.gif

    [TMB]

  9. Re:Natural carbon sequestration via coral? by Red+Flayer · · Score: 5, Informative

    On a chemical level, how does this differ from growing coral?

    Well, coral (and shellfish) can sequester carbon, but this only works as long as the water is sufficiently non-acidic. The problem is that as atmospheric CO2 is absorbed into the oceans, some of it becomes carbonic acid -- and the acidification of the water means that corals, and shellfish shells, dissolve.

    One nice effect of adding lime is that it lowers the acidity of the water, thereby allowing coral and shellfish to continue sequestering carbon.

    --
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  10. Re:Oh yeah! Interference FTW. by lyml · · Score: 5, Informative

    You actually need both things... Because all of it has an impact.

    That bicycle? It produced as much or more pollution as the car burning the gasoline to produce it unless you're making it entirely out of wood. The same goes for most of the other ones you brought up.

    By themselves, they don't accomplish much of anything- and actually in some cases are worse than the "fixes" we've done in the past (Something else you mentioned...).

    You've got to take in an even bigger picture than you're doing- otherwise you're no better than the people you're tarring with that brush of yours.

    Uhm no?

    Making a bike produces a negligible amount of CO2 compared to driving a car, your statement is downright false.

  11. Re:This scares the hell out of me by Daryen · · Score: 5, Informative

    Despite the political rhetoric we have no proof as to how much human activity is contributing to any warming trends, and even less of an idea on the possible side effects of any direct intervention. Other scientists have actually proposed putting more particulate pollution into the air to create a mild 'nuclear winter' style cooling in order to offset any rising temperatures.

    I'll leave out the fact that temperatures globally have been flat for several years now, but I will point out in closing that hair brained schemes such as this one remind me of a five year old child trying to rebuild a Formula 1 engine with a pair of chopsticks. We are so very ignorant of how and why we have or can effect the climate. The sheer hubris of some people today who assume we have such great control over climate just amazes, and scares, me.

    I agree that the climate is extremely complex, and that while we cannot understand all of the factors involved, we can draw some simple conclusions about some of the effects we are having on the environment.

    You probably already know that humans produce a lot of carbon dioxide. We breathe it out, we burn things, and our agricultural and industrial processes create even more.

    You probably also know that carbon dioxide is a greenhouse gas, and that greenhouse gasses increase warming due to sunlight.

    You may or may not know that the ppm of carbon dioxide has been increasing over the years.

    I propose that you cannot prove that we aren't increasing the temperature of the planet

  12. Re:Ocean of Acid by Anonymous Coward · · Score: 5, Informative

    TFA says they did think of this years ago but the problem was back then they wanted to do it on a truly global scale and, with the exception of a few places, getting the lime out of limestone and to the ocean generally puts more CO2 into the atmosphere than the lime would help the ocean take back out of the atmosphere.

    IOW, "net negative". Somebody seems to have had the genius thought that just because it can't be done everywhere and act as a "silver bullet" for global warming doesn't mean it isn't worth getting what help it can provide by doing it in those places where it doesn't produce more CO2 than it scrubs.

  13. Re:Mitch said it best by Free+the+Cowards · · Score: 4, Informative

    I'm kind of surprised you know enough to know that it sounds like him but haven't heard it. It's from his CD, Mitch All Together, on the track titled, oddly enough, Saved By The Buoyancy Of Citrus.

    --
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  14. Re:Sure... by GameboyRMH · · Score: 4, Informative

    A budding GW denier eh? Well don't give up! Learn more and get right back to us with your next poorly-researched knee-jerk conclusion!

    http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/

    --
    "When information is power, privacy is freedom" - Jah-Wren Ryel
  15. Re:Sure... by hardburn · · Score: 5, Informative

    It's a way of hardening the water, which in turn increases its ability to absorb CO2 without increasing the acidity of the water. The basic chemistry is used by aquarium hobbyists to keep their acidity stable.

    Many fish keepers go to great lengths to keep their water in a tight range to mimic their fish's natural environment as close as possible, but empirical evidence suggests that fish can tolerate a wide range of hardness and acidity provided that changes are made slowly. Additionally, it should increase the growth rate of coral.

    However, many types of fish may only breed within a given hardness range, so this may end up being a big problem.

    --
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  16. Re:Nevermind the obvious unknowns here by JakeD409 · · Score: 4, Informative

    Not sure exactly what will happen, but it will probably involve the United Nations Convention on the Law of the Sea.

  17. A slight correction... by Fallen+Andy · · Score: 4, Informative
    Slaked Lime = Calcium Hydroxide

    Quick Lime = Calcium Oxide

    Andy

  18. Re:Sure... by digitig · · Score: 5, Informative

    It isn't GW denying, it's that CO2 probably accounts for less than 25% of the greenhouse effect. If we're looking to manage the greenhouse effect ("manage" because if we overdo it we get a global cooling problem) then it's no good just looking at CO2. The fact that the effects of greenhouse gasses are often quoted in CO2 equivalent tends to mislead people into thinking that CO2 is the only gas that matters.

    --
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  19. Re:Sure... by ninjagin · · Score: 4, Informative

    Huh?

    I hate to parse, but I don't recognize any of those statements as having come from environmentalists.

    Let's keep around the old trees and kill the young ones.

    This overstatement is soooo very hyperbolic, it'd be amusing if it wasn't so pathetic. Old growth forests just don't exist anymore in the US, at least not to any appreciable degree. We've already cut down all the old trees. As a rule, environmentalists are against clearcuts and for sustainable forestry (more expensive to log, but keeps trees of various ages in a given acreage, offers a diverse understory, allows for some logs to lie where they fall and includes fire as part of the natural cycle). That said, it's recognized even by the environmentalist groups that Boise Cascade and other wood & pulp products producers either own or lease their lands outright and can ultimately tree-farm and clearcut to the extent they desire.

    You can't clear out any of the underbrush, and we have to stop wild fires right away! (See California)

    Wow. What a broad brush you've got there. Brush clearing has always been okay, even on public lands. Some states contract out for it, and others use -=gasp=- FIRE to clear it out. It's taken as a given that any property owner needs to clear brush from their houses. Did it every occur to you that natural wet-dry cycles can leave a lot of dry scrub when drought eventually sets in? In CO, we've got millions and millions of dead trees from pine bark beetle. Do you think those dead trees are all going to sit there? Hell no, the state's already permitting for logging most of it out, on millions of acres, as they should.

    You can't have nuclear power plants, the waste contaminates the environment. (Breeder reactors anyone?)

    I'm pretty sure that one of the founders of the Sierra club has come to endorse nuclear energy. Regardless, the main environmetalist objection to nuclear energy hasn't been in waste disposal anyway (almost all nuclear waste from power plants is held on-site) -- it's been with the way uranium is mined and what the tailings and ore processing leachfields do to rivers & the water table. Think this is whining? It's not. My state (Colorado) already has a superfund site to show for it... Uravan. Breeder reactor development got squashed 25 years ago, and it's only now being talked about again. Maybe the discussion is ready to re-open. I dunno.

    Yep, it's those annoying enviro-hippies. They only exist to make things difficult. They just don't have any other reason for what they do other than being annoying. Oooooh, and they're sooooo annoying. Sooooo annoying that the entire US government has been able to ignore them for eight years. Ooooooh, they're soooooo powerful. Soooo scary! Like martians! Like clowns! BooogaBoogaBooogaBoogaBoooga!

    Scared yet? Didn't think so. If you look closely at the issues you'll see that there's a balance to be struck between competing goals. The best outcomes are the ones that nobody's entirely satisfied with, but let things go forward. We can't achieve those outcomes if folks sit back, re-enforce their stereotypes, point fingers and blame blame blame, as you do.

    Jeezus, what bunch of hand-wringing whiny pussies conservatives have become.

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