Follow Slashdot blog updates by subscribing to our blog RSS feed


Forgot your password?
Earth Science

A Hidden Loop In the Carbon Cycle Discovered 310

Googlesaysmysiteisdangerousanditisn't! writes "A recent article in Science says that researchers in China and the US have found massive carbon uptake in the world's deserts. The effects of this are huge. 35% of the Earth's land surface is desert, and the uptake equates to 5.2 billion tons of carbon sequestered each year. This is more than half of the carbon released by humans. In these 'dry oceans,' the grains of sand allow the carbon dioxide to enter and react with alkaline soil to become carbonates. Another scientist suspects that biotic desert crusts, alkaline soils, and increased precipitation may be driving the uptake."
This discussion has been archived. No new comments can be posted.

A Hidden Loop In the Carbon Cycle Discovered

Comments Filter:
  • Obviously (Score:5, Funny)

    by mnemocynic ( 1221372 ) on Wednesday August 06, 2008 @09:13PM (#24505195)
    The solution is obviously to cut down more trees and make more deserts, right?
    • Not just a joke (Score:5, Interesting)

      by EmbeddedJanitor ( 597831 ) on Wednesday August 06, 2008 @09:49PM (#24505453)
      Forests soak up a lot of carbon, but then drop a lot of leaves. When the leaves rot they give off CO2 and methane. Methane is far worse as a green house gas than CO2 - by a factor of over 20.
      • by Nymz ( 905908 ) on Wednesday August 06, 2008 @10:19PM (#24505675) Journal
        "Each year, the Rainforest is responsible for over three thousand deaths from accidents, attacks or illnesses." - Rainforest Schmainforest [] and now forests are rotting and giving off greenhouse gases. We must act to stop these forests from further encroaching upon our Earth-friendly deserts, it is time we cleaned them up.
      • Methane doesn't stay in the atmosphere as long as CO2.

        • Re: (Score:3, Informative)

          by TapeCutter ( 624760 ) *
          Yes, but unfortunately one of the byproducts of methane decomposition is CO2.
        • Re: (Score:3, Funny)

          by Anonymous Coward

          Methane doesn't stay in the atmosphere as long as CO2.

          You've obviously never been in the same room as me! :)

      • by TheLink ( 130905 )
        So chop trees down, make furniture, paper, packaging out of them, landfill the discards then grow more trees.

        Simple :).

        Not so simple - work out a way to do it efficiently so that you only need to use the equivalent of a small percentage of trees chopped down to provide energy and resources for all that.

        Once you worked that out, you're carbon negative.
      • Re:Not just a joke (Score:5, Insightful)

        by Max Threshold ( 540114 ) on Wednesday August 06, 2008 @11:38PM (#24506231)
        Trees are still much better CO2 scrubbers than other plants. Rush Limbaugh is fond of pointing out how much CO2 is absorbed by suburban lawns, but most of it goes back into the atmosphere when the lawn is cut. By contrast, most of the carbon sequestered by trees is not in the leaves, but in the woody parts. And it remains sequestered for hundreds of years, or longer depending on what happens to the tree when it dies.
        • by fredmosby ( 545378 ) on Thursday August 07, 2008 @01:14AM (#24506681)
          ... but most of it goes back into the atmosphere when the lawn is cut.

          That really depends on what the homeowner does with the grass after it is cut. If it goes in a land fill most of the carbon probably stays underground. If if goes into a compost heap then more of the carbon goes back into the atmosphere.

          Although I personally think laws waste a lot of resources (especially in LA where I live).
      • Re:Not just a joke (Score:4, Informative)

        by MrCreosote ( 34188 ) on Thursday August 07, 2008 @12:21AM (#24506425) []

        Wild untouched forests store three times more carbon dioxide than previously estimated and 60% more than plantation forests, a world-first study of "green carbon" and its role in climate change shows.

      • Re:Not just a joke (Score:5, Insightful)

        by meringuoid ( 568297 ) on Thursday August 07, 2008 @03:36AM (#24507259)
        When the leaves rot they give off CO2 and methane. Methane is far worse as a green house gas than CO2 - by a factor of over 20.

        True, but CH4 + 3O2 -> CO2 + 2H2O, which won't take long in an oxygen-rich atmosphere, and just gives us carbon dioxide back; the same carbon dioxide that was absorbed when the leaves grew in the springtime. Meanwhile the tree on the ground has grown over the course of the year, and locked up a bit more carbon in the form of wood.

    • Re:Obviously (Score:4, Informative)

      by Captain Splendid ( 673276 ) <capsplendid&gmail,com> on Wednesday August 06, 2008 @10:28PM (#24505759) Homepage Journal
      The solution is obviously to cut down more trees and make more deserts, right?

      Sure, as long as you don't skimp on the sandworms.
    • by jo42 ( 227475 )

      cut down more trees and make more deserts

      And what is going to product the oxygen [that we need to exist]?

  • PDF (Score:2, Insightful)

    by Anonymous Coward
    How about a PDF warning on that link, editors?
    • Re:PDF (Score:5, Insightful)

      by MyLongNickName ( 822545 ) on Wednesday August 06, 2008 @09:31PM (#24505315) Journal

      It is called the status bar. It shows you what a link is pointing to.

      • by tknd ( 979052 )
        If he uses a mac, safari doesn't show the status bar by default.
        • by bucky0 ( 229117 )

          And if you're using a mac and sticking to the defaults, the default pdf viewer doesn't crap out and lock your browser process while loading.

    • by zobier ( 585066 )

      You can set Firefox to prompt you to save a PDF instead of opening it with a plugin.
      Flash I will sometimes tolerate, but I won't let Acrobat Reader any where near my browser.

      Tools > Options > Applications > Adobe Acrobat Document > Always ask

  • by PC and Sony Fanboy ( 1248258 ) on Wednesday August 06, 2008 @09:14PM (#24505215) Journal
    Does this mean that all the salinization that has been going due to irrigation because america grows FRUIT in the desert is actually a good thing?

    Does this mean that scientists now think that we don't have enough deserts?

    I'm all for global warming (it is cold up here in canada), but I'm pretty sure we've got enough desolate landspace...
  • so the MVP is not Kobe...but Gobi?
    (or the sahara if u'r in africa)

  • by Dripdry ( 1062282 ) on Wednesday August 06, 2008 @09:23PM (#24505265) Journal

    Ok. So they've found a massive carbon sink that was unaccounted for. Great!

    They also say that due to changing conditions, including increased precipitation, there is more uptake occurring.

    Does this process ever reach a point where it stops? Is there only so much carbon that can be converted/sequestered? If conditions change enough, will this huge carbon sink disappear rapidly, adding a HUGE amount of carbon to the atmosphere?

    This is fascinating, but it still feels to me like this situation could be as fragile as any others we've discovered around the globe.

    • Re: (Score:3, Insightful)

      by zappepcs ( 820751 )

      I think that this is just an indication that we TRULY do not understand how the global climate actually works. There have been billions of years of fluctuations and change to get the Earth to where it is now. We have no idea how most of that worked and only a vague idea of what is happening now. In the search to figure out why temperatures are rising globally, several things have been named as contributory causative factors. There is NO definitive proof that x, y, or z has caused global warming, only that i

      • There is in fact little understanding of how the position of the Earth/solar system in the plane of the Milky Way affects solar radiation et al and thus how it affects planet temperatures. Desert sand is not the cure, it is a possible cure. There are others, like cutting down on human CO2 emissions etc.

        While there's definitely a lot of things that affect us directly which we know very little about (such as gravity), I really don't think the position of our solar system within the Milky Way has much effect o

        • Re: (Score:3, Interesting)

          by zappepcs ( 820751 )

          I've heard one theory (no citation, sorry) that as the solar system moves in alignment with the acretian? disk of the Milky Way this affects solar sunspot activity. That would affect global climate. The thought was changes in space radiation hitting the sun affects it's activity, much as radiation is believed to cause lighting in storms. It's a theory, and sounds plausible. There just is no evidence as yet as to whether this is true and how much it would affect global climate.. The Sun has been quiet lately

      • by Aphoxema ( 1088507 ) * on Wednesday August 06, 2008 @10:15PM (#24505639) Homepage Journal

        I think a large part of greenhouse emissions being the blame is people want something they can point their finger at and put it on with the belief there is something they can do to change it.

        The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.

        Unfortunately, awareness isn't a terribly useful thing especially for the masses. When people learn part of the information, the wrong parts of the whole idea gets heavily associated and then it becomes misinformation.

        Ironically, we need less Al Gores and interest groups and treehuggers trying to get 'the word out', we need more university graduates being interested in the study.

        Since people can't simply be told there's nothing to worry about yet, they're going for second worst and being fed and recycled the idea that it is everyone's responsibility to ... and that by doing ... it will make things better.

        • by Splab ( 574204 )

          Wouw, so you are saying that since we can't prove we are the ones causing climate changes we should just keep on burning coal, wasting resources etc?

          How about, yes we don't know whats causing it, but the amount of crap we are emitting into the atmosphere can't be good, so perhaps - just perhaps - it would be smart to live a bit cleaner, take the bike rather than car, turn of those items on stand by. If we are lucky; being a bit cleaner about our living could potentially help down the road.

        • by Moraelin ( 679338 ) on Thursday August 07, 2008 @03:13AM (#24507143) Journal

          Actually, I'm getting the idea that for some people the goal isn't even to point fingers at something, but to point fingers at someone. Subtle but important difference.

          Actually, even that is the superficial version. The longer one is that a bunch of people need not just to feel superior to you all, but to be a part of some grand cause that's never done or achievable. The last part is the more important one. It's what makes such grandiose tactually an _easy_ way out.

          The quote which comes to mind, and kinda sums it all up, is, "It is easier to be a "humanitarian" than to render your own country its proper due; it is easier to be a "patriot" than to make your community a better place to live in; it is easier to be a "civic leader" than to treat your own family with loving understanding; for the smaller the focus of attention, the harder the task."

          So people seek some grandiose cause to fight for, so they don't have to acknowledge that they don't achieve the small ones.

          And again, it better be something so grand that nobody actually expects any given individual to achieve anything tangible. In a "small" task, like, say, "I want to finally get out of debt", or "I'll take some lessons and try to find a better job", or "I'll finally have a talk to my son about starting fights at school", there are very clear criteria as to whether you achieved anything or not. And at some point you have to admit that you didn't. It's not a very motivating thought. Worse yet, it might involve some personal effort and change. Good grief.

          On the other hand, "saving the world" (from whatever global threat, from MS to global warming to God's wrath) is _easy_. It's a task nobody really expects you to achieve. So you can just moan and bitch a little about how the _other_ people should change, then be smug that you did your part. If it didn't achieve anything, it's because everyone _else_ didn't immediately drop everything and do as you said. Or even if they did, and it didn't actually work, hey, it's still their fault not yours: they didn't do enough, or didn't really understand you.

          Big surprise that people choose the latter, eh? They're easy.

          And it's not even something new. Since the dawn of time people have got into such grandiose fights to save others from whatever. For a long time, mostly from worshiping the wrong gods, or from worshiping them all wrong, or from some moral/philosophical detail that will doom us all. Mostly because they didn't have some scientific doomsday scenario, so God's Wrath was the best threat they had. Now they can do better.

          • Re: (Score:3, Insightful)

            by NickFortune ( 613926 )

            As Larry Niven once pointed out, there is no cause so right that you can't find a fool fighting for it somewhere.

            What you say about human is probably entirely accurate, and I have no doubt it describes many people on both sides of the debate.

            Still, I can't help feeling that it's drifting away from the point. The issue is climate, not psychology.

        • by Urkki ( 668283 ) on Thursday August 07, 2008 @03:20AM (#24507175)

          The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.

          But you see, we are constantly changing something! We are adding carbon to the carbon cycle of the biosphere, and adding a lot of it, and increasing the carbon release rate. That's a change, and we're doing it, and there's no way we'll stop doing it, so option of "not changing anything" is out. But there is the uncomfortable option of trying to change our planet and biosphere as little as possible...

        • Re: (Score:3, Insightful)

          by fbjon ( 692006 )
          Don't complain too much. If all we manage to do is reduce pollution, I'm totally fine with that. I'm also fine with people taking more responsibility for what they do and consume, regardless of any effect it has on global warming.
        • by speedtux ( 1307149 ) on Thursday August 07, 2008 @07:16AM (#24508055)

          The real problem isn't nature, and to your point, the real solution isn't changing anything, it's dedicated research.

          But we are changing something: we are emitting CO2 into the atmosphere, and our emissions are growing exponentially. That can't go on: either we stop voluntarily, or we run out of fossil fuel, or we get a climate catastrophe; there simply is no third possibility.

          When you are saying that we shouldn't "change anything", you are actually advocating continuing a massive global change, a massive experiment with global climate. People like you are playing word games: you simply redefine what amounts to deliberate and massive change as "no change" by reframing the issue.

      • by mmurphy000 ( 556983 ) on Wednesday August 06, 2008 @10:29PM (#24505775)

        Until we know *MUCH* more about global climate control knee jerk reactions should be kept to a minimum.

        Depending on how you define "knee jerk", I disagree.

        Reducing overall usage of oil is a good thing for many reasons outside of the potential environmental benefits, including:

        • Reducing the world's dependency on a non-renewable resource that, depending on who you ask, may be running out (or at least getting increasingly difficult to extract in the desired quantities for reasonable costs)
        • Reducing the world's dependency on a resource that, in many cases, lies in areas with political turmoil (e.g., Middle East)
        • For the countries that establish relative expertise, serving as a source of innovation-based new jobs

        So, if it's "knee jerk" for the US to ratchet up CAFE requirements (and the equivalents for trucks and trains) so we become best-in-breed at fuel efficient transportation, or for the US to increase investing in alternative energy sources, then I'm all for "knee jerk" reactions.

        • by demonlapin ( 527802 ) on Wednesday August 06, 2008 @10:42PM (#24505857) Homepage Journal
          CAFE is crap for really reducing emissions; it gave us the SUV as family vehicle (because station wagons, the former family machine, were subject to CAFE as cars, but SUVs, as light trucks, were not). You want higher fuel efficiency, tax the hell out of gasoline and diesel the way the Europeans do. Simple and easily enforced.

          CAFE is just another bureaucratic boondoggle, though it does have the merit that those who can afford larger cars subsidize the purchase of econoboxes.

          • by Kupfernigk ( 1190345 ) on Thursday August 07, 2008 @03:55AM (#24507347)
            In fact you are right, and the net result is interesting. In Europe we pay about the same PER MILE for fuel as you do in the US, even though it costs twice as much per gallon. The high tax causes most of us to buy fuel efficient cars, our smaller city streets (built before cars) encourage us to use smaller vehicles. But our road deaths are no worse than the US and often much better.

            The problem with CAFE was that it was indeed a boondoggle - the mandated efficiency improvements were actually less than were achieved automatically by European taxation levels, and as you note it was easily evaded with the "light truck" class.

            Taxation of fuel is sensible because it is a tax on actual consumption. Most people are able to reduce their consumption by varied means - aggregated journeys, car shares, vacations closer to home, reducing acceleration, using mail order more - without changing their vehicles.

          • Re: (Score:3, Interesting)

            by mmurphy000 ( 556983 )

            CAFE is crap for really reducing emissions; it gave us the SUV as family vehicle (because station wagons, the former family machine, were subject to CAFE as cars, but SUVs, as light trucks, were not).

            That's a matter of rewriting the CAFE law. It's not like SUV-as-light-truck is some fundamental constant in the universe.

            You want higher fuel efficiency, tax the hell out of gasoline and diesel the way the Europeans do. Simple and easily enforced.


            • That gives slow, indirect impetus to car manufacturers to
        • Please don't misunderstand me, reducing usage of fossil fuels (if they are still classified as fossil fuels) is absolutely a good thing, but it will NOT fix global warming and should not be thought of as THE cure. It hurts us all to pay higher taxation to fix something tomorrow that is not really broken when we can slowly fix it over 10-15 years at a much reduced cost and more sustainable pace. One recent headline statement I saw was "Why are we supposed to believe that 31 mpg is awesome?" There are many th

          • There is also a problem with say, North America makes changes, but growing nations like China and India do not. They will replace our former gas guzzling ways and the sum total is a zero balance.

            There's a problem with that logic. Let's say we can define it as some figures (pulled out of a hat) like so:
            US: 500 units
            EU: 480 units
            China: 100 units
            India: 80 units
            Total: 1160 units
            Your concern is that if we reduce, and they increase, it'll be zero sum, like this: US: 300 units
            EU: 300 units
            China: 280 units
            India: 280 units
            Total: 1160 units
            MY concern is that if we don't reduce, and they increase, it'll be much worse!: US: 500 units
            EU: 480 units
            China: 280 units
            India: 280 units
            Total: 1

      • Quote: "There is in fact little understanding of how the position of the Earth/solar system in the plane of the Milky Way affects solar radiation et al and thus how it affects planet temperatures. Desert sand is not the cure, it is a possible cure. There are others, like cutting down on human CO2 emissions etc."

        On the contrary. We know that there is an extremely strong correlation -- geologic and historical -- between earth temperatures and solar flares. Inverse correlation, actually.
      • by llZENll ( 545605 )

        We don't have to understand how the global climate works to realize humans are adding gases to the atmosphere and chemicals to the water that wouldn't be there otherwise. There is no point in tring to reverse what is happening, I don't think that is even possible, and warming may not even be due to us. But trying to work toward a lifestyle which does as little as possible to the environment should be on everyones mind.

    • by kesuki ( 321456 )

      carbonates, like calcium carbonate, don't worry we'll mine it all up and feed it to feed lot cattle while we double their size in 6 months.

      rain moves the carbonates, and makes more room for further carbonation, so more rain increases the capacity of this heat sink, to a point. if the rain is intense and short followed by weeks of heat, it works best for this process.

      it's the heat of the desert that drives the chemistry that allows formation of carbonates. and rain that refreshes the availability of oxygen

    • by Qzukk ( 229616 )

      including increased precipitation

      Does this process ever reach a point where it stops?

      Personally, I'd say it stops when it rains enough to make it not a desert anymore.

  • by BlueParrot ( 965239 ) on Wednesday August 06, 2008 @09:41PM (#24505393)

    If this is indeed the case it would seem a bit strange that it has not been detected before. I mean with all the climate change debate going on there has been quite close scrutiny of the estimates of CO2 going into and out of the atmosphere, so if this is as big a carbon sink as described it would have to mean that the other sinks ( i.e the ocean and the biosphere ) are less potent than previously assumed.

    • by Aphoxema ( 1088507 ) * on Wednesday August 06, 2008 @10:17PM (#24505659) Homepage Journal

      You'd think that exactly what you're looking for wouldn't be right in front of you until you find it is.

      Now, where the Hell are my keys...

    • You would, indeed, think that. I think the issue is that perhaps the close scrutiny of CO2 levels has unfortunately not been so close, at least up until now (or however long this paper took). The whole Climate Change/Greenhouse Gas debate is drawing so much attention and so many funds away from the work itself that it's making most of either side a moot point - we're getting close to when we'll just find out *when* it happens.

      This isn't good news for us Climate Change folks. Not only does this show that

    • by Reziac ( 43301 ) *

      Probably not detected because it's been assumed all along that desert chemistry is fairly static, due to the general lack of "input" from the usual reactives, ie. water and biomass. So... I'd guess no one ever actually LOOKED.

      Ooops... now, what other assumptions about climate, and climate change, might be completely broken??

  • Sooo... (Score:2, Interesting)

    by bsDaemon ( 87307 )

    Is this why all the oil is in the middle east?

    • Dunno what that has to do with it...

      Living in the Canadian Prairies, we have more oil than a lot of places in the world. Considering it's 'winter' here for 9 months of the year (according to Californian standards).

      My response to you is: what? *blink*

    • Re:Sooo... (Score:5, Informative)

      by Anonymous Coward on Wednesday August 06, 2008 @11:17PM (#24506117)

      No, the prolific amount of oil in the Middle East is mainly related to organic carbon [] in source rock [] deposits that formed in the marine environment. The source rocks in the Middle East are particularly widespread and productive.

      The article is talking about carbonate [] (i.e. minerals with CO3 in their structure), which is completely different and is often referred to as "inorganic carbon". It's as different as algae (organic carbon) and sea shells (carbonate). They both involve carbon and both can have biological origins, but you can't generate oil from carbonate. You need molecules with plenty of H and C for that (i.e. hydrocarbon molecules).

      You can, however, find holes in carbonate rocks. In the right setting these can contain oil that has migrated into the porous rock from organic-rich source rocks nearby. Such rocks are known as petroleum reservoirs. Again, the Middle East has some spectacular reservoirs with very high porosity and permeability, allowing for plenty of space to hold the oil and to allow it to flow out. For example, the Ghawar field [], which is the biggest oil field in Saudi Arabia and the world, has limestone reservoirs with up to 35% porosity by volume -- i.e. 35% of the volume isn't rock, but open spaces filled with fluid (either oil, gas, or water). That's extraordinarily high porosity. It's full of holes like a sponge.

      So, if you want the short answer to why there is so much oil in the Middle East: 1) spectacularly prolific and widespread organic-carbon-rich source rocks, 2) highly porous and permeable reservoir rocks (some of which are carbonates, some of which are other rock types), and 3) large "trap" structures, which I haven't discussed, but basically refers to the geometry of the porous reservoir and an impermeable seal that keeps the oil/gas from leaking out.

      It has very little to do with the modern deserts that are widespread in that part of the world today. Many of the conditions necessary for the large oil deposits were set up far enough back in geological history that today's climate is mostly irrelevant.

  • by Anonymous Coward

    We [all of humanity, as in not one single person on the planet] do not even understand 1/100th of 1/100th of 1% of how our planet works. A lot of people believe that we are making a huge impact, but if you really do look at the big picture, we [all of humanity] actually take up a very small percentage of the planet. There is a lot of uncovered ground and water that works to clean up after itself and us.

    The planet is not out of balance, we are not causing that much damage and in most places where we have c

  • A nice littlle nuclear war plus aggressive deforestation should do it!

  • Misleading Summary (Score:5, Informative)

    by Conspicuous Coward ( 938979 ) on Wednesday August 06, 2008 @11:52PM (#24506285)
    TFA is far more cautious about these findings than the summary suggests. Also, no scientists are currently suggesting that these findings are likely to have a significant impact on the level of anthropogenic global warming.

    The effect could be huge: About 35% of Earth's land surface, or 5.2 billion hectares, is desert and semiarid ecosystems. If the Mojave readings represent an average CO2 uptake, then deserts and semiarid regions may be absorbing up to 5.2 billion tons of carbon a year.


    For now, some experts doubt that the world's most barren ecosystems are the longsought missing carbon sink. "I'd be hugely surprised if this were the missing sink. If deserts are taking up a lot of carbon, it ought to be obvious," says William Schlesinger, a biogeochemist at the Cary Institute of Ecosystem Studies in Millbrook, New York, who in the 1980s was among the first to examine carbon flux in deserts. Nevertheless, he says, both sets of findings are intriguing and "must be followed up." Scientists have long struggled to balance Earth's carbon books. While atmospheric CO2 levels are rising rapidly, our planet absorbs more CO2 than can be accounted for.


    Provided the surprising CO2 sink in the deserts is not a mirage, it may yet prove ephemeral. "We don't want to say that these ecosystems will continue to gain carbon at this rate forever," Wohlfahrt says. The unexpected CO2 absorption may be due to a recent uptick in precipitation in many deserts that has fueled a visible surge in vegetation. If average annual rainfall levels in those deserts were to abate, that could release the stored carbon and lead to a more rapid buildup of atmospheric CO2--and possibly accelerate global warming.

    This is not, as some posters are implying, published science that concludes the IPCC predictions are in any way likely to be inaccurate, or that carbon is accumulating in the atmosphere at a rate lower than previously thought.
    This is a news article in science detailing some interesting research showing that deserts may be absorbing more carbon than was previously thought, and that this may account for the fact that atmospheric measurements show the earth is absorbing carbon at a higher rate than can be accounted for by currently known sinks. The amount of CO2 in the atmosphere is known from atmospheric measurements, and is higher than at any time in the last 650,000 years.

"I'm not afraid of dying, I just don't want to be there when it happens." -- Woody Allen