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New Study Shows Three Abrupt Pulses of CO2 During Last Deglaciation

Posted by samzenpus on from the it's-getting-hot-in-here dept.

vinces99 writes A new study shows that the increase of atmospheric carbon dioxide that contributed to the end of the last ice age more than 10,000 years ago did not occur gradually but rather was characterized by three abrupt pulses. Scientists are not sure what caused these abrupt increases, during which carbon dioxide levels rose about 10 to 15 parts per million – or about 5 percent per episode – during a span of one to two centuries. It likely was a combination of factors, they say, including ocean circulation, changing wind patterns and terrestrial processes. The finding, published Oct. 30 in the journal Nature, casts new light on the mechanisms that take the Earth in and out of ice ages.

"We used to think that naturally occurring changes in carbon dioxide took place relatively slowly over the 10,000 years it took to move out of the last ice age," said lead author Shaun Marcott, who did the work as a postdoctoral researcher at Oregon State University and is now at the University of Wisconsin-Madison. "This abrupt, centennial-scale variability of CO2 appears to be a fundamental part of the global carbon cycle."

Previous research has hinted at the possibility that spikes in atmospheric carbon dioxide may have accelerated the last deglaciation, but that hypothesis had not been resolved, the researchers say. The key to the new finding is the analysis of an ice core from the West Antarctic that provided the scientists with an unprecedented glimpse into the past."

24 of 132 comments (clear)

  1. Abrupt, but like 100 years abrupt? by Anonymous Coward · · Score: 5, Insightful

    "However, the researchers say that no obvious ocean mechanism is known that would trigger rises of 10 to 15 ppm over a timespan as short as one to two centuries."

    We're way, way, way beyond 10 to 15 in 200 years.

    1. Re:Abrupt, but like 100 years abrupt? by saloomy · · Score: 4, Interesting

      Sounds like they really just don't know.
      It likely was a combination of factors, they say, including ocean circulation, changing wind patterns and terrestrial processes.

      But at least they are studying and learning.
      "This abrupt, centennial-scale variability of CO2 appears to be a fundamental part of the global carbon cycle. "Previous research has hinted at the possibility that spikes in atmospheric carbon dioxide may have accelerated the last deglaciation, but that hypothesis had not been resolved, the researchers say.

      The earth has been from +14 to -6 degrees on average from where it is today. Historically speaking, were in the "colder than usual" range of the bell curve today, and thats with using ice cores to detect CO2 levels and temperature histories. Its not like we had a thermocouple hooked up to a server recording that data for millions of years. These deductions are best effort conclusions on data that only tells a very broad stroke of the story.
      What upsets me is how demonizing the argument about Global Warming / Climate Change is. The earth will change its temperature. That will happen with or without us, just look at the historical record. Earths temperature isn't stable. And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today, unless you believe the earth is 6000 years old!
      They were a part of the global carbon cycle, and buried during mass extinction events and processes that sequestered them to where they are today. It isn't science to say "for sure this and for sure that". Its science to say: "To the level of our current understanding...". Thats it. You can't know for certain, just like they didn't know for certain that the earth was the center of the universe, even though it was proselytized. Its not OK to attack the character of an individual when they are skeptical of your conclusions. All of science works better when there are those who are skeptical. It refines your proof if you are right, or betters your understanding if you are wrong.

      As for the problems associated with climate change, it will happen. For those of us living where it will flood, there will be a new continent to live on, once it unfreezes (again!).

    2. Re:Abrupt, but like 100 years abrupt? by CaptainDork · · Score: 3, Insightful

      Science, shmience.

      Ken Ham is a crackpot, without character, on the order of Fred Phelps.

      --
      It little behooves the best of us to comment on the rest of us.
    3. Re:Abrupt, but like 100 years abrupt? by quantaman · · Score: 3, Interesting

      Sounds like they really just don't know.

       
        It likely was a combination of factors, they say, including ocean circulation, changing wind patterns and terrestrial processes.

      Actually they do know, they just don't know precisely.

      You're basically implying their knowledge is zero, the truth is they've already ruled out countless possibilities, they just haven't gotten all the way to the truth.


      "This abrupt, centennial-scale variability of CO2 appears to be a fundamental part of the global carbon cycle. "Previous research has hinted at the possibility that spikes in atmospheric carbon dioxide may have accelerated the last deglaciation, but that hypothesis had not been resolved, the researchers say.

      The earth has been from +14 to -6 degrees on average from where it is today. Historically speaking, were in the "colder than usual" range of the bell curve today, and thats with using ice cores to detect CO2 levels and temperature histories. Its not like we had a thermocouple hooked up to a server recording that data for millions of years. These deductions are best effort conclusions on data that only tells a very broad stroke of the story.

      Interesting but I'm not sure how it's relevant.

      What upsets me is how demonizing the argument about Global Warming / Climate Change is. The earth will change its temperature. That will happen with or without us, just look at the historical record. Earths temperature isn't stable.

      You're arguing a strawman, no one has ever argued that climate is completely stable without us. The claim is that we're undergoing an extreme and dangerous rate of change due to human causes.

      And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today, unless you believe the earth is 6000 years old!

      Ahh, I get it.

      AGW deniers are often associated with Young Earth Creationists (YECs) because the religious right and YECs are fairly well represented in the AGW denier community. Therefore you compare AGW proponents to YECs, and if any show outrage at the comparison you can say they're hypocritical because of how people associate YECs with denialists.

      They were a part of the global carbon cycle, and buried during mass extinction events and processes that sequestered them to where they are today. It isn't science to say "for sure this and for sure that". Its science to say: "To the level of our current understanding...". Thats it. You can't know for certain, just like they didn't know for certain that the earth was the center of the universe, even though it was proselytized. Its not OK to attack the character of an individual when they are skeptical of your conclusions. All of science works better when there are those who are skeptical. It refines your proof if you are right, or betters your understanding if you are wrong.

        As for the problems associated with climate change, it will happen. For those of us living where it will flood, there will be a new continent to live on, once it unfreezes (again!).

      And again I'm not sure what the point of this section was other than to accuse the researchers of not doing science... and then promptly follow that up with a deliciously ironic complaint that people shouldn't "attack the character of an individual when they are skeptical of your conclusions".

      --
      I stole this Sig
    4. Re:Abrupt, but like 100 years abrupt? by crioca · · Score: 2

      And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today, unless you believe the earth is 6000 years old!

      Okay, I don't think you understand the issues that climate change presents; for the Earth to sustain a healthy biosphere with 7+ billion humans we've had to develop a lot of infrastructure to make effective use of it's resources. Changes in the climate will require us to devote resources to re-configuring our infrastructure, the faster it happens, the more resources we'll need to devote, which will impact living standards. We do not know exactly how high the cost will be, but we do know that it will be cheaper if we act now.

    5. Re:Abrupt, but like 100 years abrupt? by Truth_Quark · · Score: 2

      Historically speaking, were in the "colder than usual" range of the bell curve today, and thats with using ice cores to detect CO2 levels and temperature histories.

      *sigh*

      Using ice cores, we're much warmer than usual.

      Earths temperature isn't stable.

      So we should warm the earth much faster than it warms naturally, and upwards from the top of an interglacial when all the existent species on the planet, plus all our infrastructure have never co-existed with the new temperature?

      Surely we can do a bit better than "Earth's temperature isn't stable, so everything might be all right". Why don't we use that science thing that has been so good for our species? We can look at what will happen to which species, and what will happen to regional climate under global warming and ocean acidification.

      And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today, unless you believe the earth is 6000 years old!

      So you're saying that if we return those carbon atoms to the biosphere, then because they were there in the carboniferous era, current species will be all right?

      That's a bold and unproven claim that goes against current estimates of extinction risk.

      Do you have a little bit more evidence or detail, or (god forbid) a scholarly paper that supports your claim that "because carbon is in the ground it must be safe to burn it"?

      Great.

      They were a part of the global carbon cycle, and buried during mass extinction events and processes that sequestered them to where they are today.

      Not generally, no. The Carboniferous had about 50 million years of build up of wood, because nothing could break down the newly evolved bark. Not a mass extinction event. Just a lot of dead trees lying on the ground. It's not cyclical, and it won't happen again until trees evolve Kevlar coating.

      Its not OK to attack the character of an individual when they are skeptical of your conclusions.

      How the hell did you get "attack the character of an individual" from the GP post? :

      "However, the researchers say that no obvious ocean mechanism is known that would trigger rises of 10 to 15 ppm over a timespan as short as one to two centuries."

      We're way, way, way beyond 10 to 15 in 200 years.

      There's no attack there. There's the observation that current atmospheric CO2 concentration rise is an order of magnitude faster than rapid increases at the end of the last interglacial.
      It didn't mention people, much less attack them. If your income was based on the proportion of climate change denial comments on slashdot, then you might feel personally attacked by it, but that's not the same thing.

      As for the problems associated with climate change, it will happen.

      It's not a step function. The lower the peak atmospheric CO2 is, the fewer the problems.

    6. Re:Abrupt, but like 100 years abrupt? by radtea · · Score: 2, Interesting

      We do not know exactly how high the cost will be, but we do know that it will be cheaper if we act now.

      Absolutely. The difficulty is that "action" has to get past a fence of anti-science, anti-technology, anti-capitalist nutjobs who say on the one hand that a) we face a civilization-ending event and b) we must not use various well-known and ready-to-go solutions to the problem, but instead must embark on an unproven revolutionary program that "changes everything!"

      Nuclear power, carbon taxes, and research in to carbon sequestration are the obvious immediate responses to climate change.

      The first two are practical, proven and ready-to-go. The latter is a backup plan.

      Instead we have left-wing idiots protesting oil pipelines, because that's where the donation dollars come from.

      With regard to carbon taxes: we have to tax something to fund government. Even righties who just want to use government money to bomb brown people generally agree with that. We can tax income, or we can tax carbon emissions. Who but a raving anti-wealth socialist would want to tax something good and wonderful like income when we can tax some basically nasty like carbon emissions instead?

      --
      Blasphemy is a human right. Blasphemophobia kills.
    7. Re:Abrupt, but like 100 years abrupt? by chmod+a+x+mojo · · Score: 3, Informative

      And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today, unless you believe the earth is 6000 years old!
      They were a part of the global carbon cycle, and buried during mass extinction events and processes that sequestered them to where they are today.

      Ummm, close, but no. It was sequestered over hundreds of million years to billions of years but the bulk of the carbon from the carbon cycle is tied up in a few places, neither of which has anything to do with mass extinctions. The huge bulk of CO2 ( currently ~400PPM atmosphere, ~60*atmosphere dissolved in the oceans, and ~10,000*oceans+atmosphere is tied up in rocks ) is tied up in the carbonates, I.E. limestones and dolostones. Coals come from swamps, and oil comes from mostly shallow-ish marine bacteria that had periodic blooms and die-offs that settled into the sediments on the seafloor and got buried.

      --
      To err is human; effective mayhem requires the root password!
    8. Re:Abrupt, but like 100 years abrupt? by jandersen · · Score: 2

      What upsets me is how demonizing the argument about Global Warming / Climate Change is

      Well, I suspect that somebody has an interest in derailing the discussion and avoiding a proper, level-headed, scientific discourse. The blame falls on both sides, but I don't think those involved in climate research are at fault; they do, after all, come out at regular intervals with corrections and amendments to their previous work, something we don't see much of from the other side.

      The earth will change its temperature. That will happen with or without us, just look at the historical record. Earths temperature isn't stable.

      This is well known and has been for more than a century. What is new is that we are contributing significantly to the warming, and that we may be in danger of initiating a very abrupt climate change; this will most likely result in major extinctions as well as causing big problems for ourselves - with 6 billion (or is it 7 now adays?) people on the planet to feed and shelter, that is not something we need.

      And for all those who argue we are burning too much fossil fuels, those carbon atoms weren't created into existence in the ground as they were today,

      True. They were extracted from our atmosphere at a time when the sun was significantly cooler than now. Returning it all to the atmosphere now would definitely not be a good idea.

      All of science works better when there are those who are skeptical. It refines your proof if you are right, or betters your understanding if you are wrong.

      Very true - but the word 'skeptical' has been hijacked by people who are not honestly skeptical. Skeptical means that you have considered the fact and reached a different conclusion, and it implies that you are willing to change your conclusion if you gain better insight. In that sense ALL scientists are skeptical.

    9. Re:Abrupt, but like 100 years abrupt? by Stuarticus · · Score: 2

      "Carbon sequestration". Yeah, the problem we have is all this carbon we are digging up and burning is causing trouble so we need to find a way of sequestering it after we burn it. Do you see the stupid part in this plan?

      --
      If you think someone isn't free to have a different definition of "freedom" you may be a tyrant.
  2. Correlation does not imply causation by laing · · Score: 4, Interesting
    How do we know the CO2 spikes caused the warming? Perhaps the CO2 resulted from increased biological activity occuring as a result of the warming.

    This sort of confusion happens a lot in science.

    1. Re:Correlation does not imply causation by DiamondGeezer · · Score: 5, Informative

      It happens a lot in science. Have you actually read "The Structure of Scientific Revolutions"? Clearly not.

      --
      Tubby or not tubby. Fat is the question
    2. Re:Correlation does not imply causation by Layzej · · Score: 3, Informative

      How do we know the CO2 spikes caused the warming? Perhaps the CO2 resulted from increased biological activity occuring as a result of the warming.

      I would think increased biological activity would have sequestered CO2 rather than released it, but you could be right that the CO2 was a result of the warming. At the same time, we know that CO2 is a greenhouse gas, so (all else being equal) increased CO2 would result in higher temperatures. That's just physics. So possibly there is a feedback loop here.

    3. Re:Correlation does not imply causation by Crashmarik · · Score: 3, Interesting

      Hows that luminous aether working out for you ?
      http://en.wikipedia.org/wiki/L...

      Little dated ? Maybe supersymetry and string theory ?
      http://scienceblogs.com/starts...

      Magnetic Monopoles ?
      http://en.wikipedia.org/wiki/M...

      Science is about being aware of what you don't understand and just how vast it is. Pseudoscience is about certainty. Maybe you can get a corrective phrenology session to clear that up ?

  3. last glacial by Black+Parrot · · Score: 3, Interesting

    We're in an interglacial, still in same ice age.

    --
    Sheesh, evil *and* a jerk. -- Jade
  4. Correlation does not imply causation by Anonymous Coward · · Score: 4, Interesting

    " Perhaps the CO2 resulted from increased biological activity occuring as a result of the warming"

    A simpler explanation is Henry's law: http://en.wikipedia.org/wiki/Henry's_law

    "carbon dioxide from a carbonated drink escapes much faster when the drink is not cooled "

    Likewise, carbon dioxide from a carbonated ocean escapes when the ocean warms.

  5. Re:Maybe something like a permafrost melting? by PopeRatzo · · Score: 4, Funny

    Don't we have several mammoth cO2 reserves around the planet, right on the verge of finally letting go?

    Don't bring my mother-in-law into this.

    --
    You are welcome on my lawn.
  6. Volcano + Oilfield? by Anonymous Coward · · Score: 2, Interesting

    There are several catastrophic event types that, if they occurred at the location of a large carbon reserve, would result in a massive pulse of CO2 released into the atmosphere.

  7. Re:Nostradamus by Tablizer · · Score: 2

    How about we give points to both sides:

    Points to GOP: The Earth's temperature is volatile such that man-made changes to it are not really anything new or unique*.

    Points to Dems: Increases in CO2 provably cause the temperature to rise.

    * Sub-counter-point: The changes will f$ck over human society either way.

    --
    Table-ized A.I.
  8. What causation? by Namarrgon · · Score: 3, Insightful

    Who said the CO2 causes anything?

    The article and summary use the words "contributed to", which we know will be true - as a greenhouse gas, any increased CO2 will amplify and contribute to further warming. Doubtless there are other causative factors involved (e.g. Milankovitch cycles), some of which may well have occurred before the CO2 release.

    The interesting question is, what triggered the CO2 pulses?

    --
    Why would anyone engrave "Elbereth"?
  9. Causation, CO2 and Warming by Robear · · Score: 5, Insightful

    [quote]How do we know the CO2 spikes caused the warming? Perhaps the CO2 resulted from increased biological activity occuring as a result of the warming. [/quote]

    CO2 is a warming gas in the atmosphere; in the absence of any other changes, adding CO2 will warm the atmosphere. However, as the article notes, we don't know what caused the quick ramp-up of CO2, and we *do* know that other factors (both cooling and warming) were in play. We also know that over time the atmosphere warmed enough to end the ice age in question.

    What is safe to say is that CO2 has a warming effect, which could be counterbalanced *and* added to by other factors. It's the overall balance of these things that tilts the scales one way or another. CO2 is just one piece.

    But it's not mistaking correlation for causation to note that adding CO2 to the atmosphere will result in increased warming. That's just basic physics. The fact that it could be offset by something else is immaterial to your point.

    --
    French - The lingua franca of Europe!
  10. Not sure the cause by argStyopa · · Score: 2

    Was it the saber-toothed tigers and their sports cars, or mainly the mammoth families and their fucking SUVs?

    --
    -Styopa
  11. Re:Nostradamus by Anonymous Coward · · Score: 2, Informative

    No, it really has. You can do tabletop lab tests to confirm it. Earth only has one way to transfer energy to space, that makes it reaaaally fucking simple to work out the radiative transfer equations. A doubling of atmospheric carbon will provably, with utter certainty, result in ~3.7W/m^2 additional warming, commonly cited as 1 degree C global temperature increase. To what degree feedbacks (most importantly water vapor) increase this is a matter of some study, but that CO2 causes warming is exactly what people are referring to when they say "settled science". The only possible disproof would be to find another way to radiate energy, and that would be detectable by satellites. The "hockey stick" graph is neither here nor there, again, you can prove this with minimal lab equipment to your own satisfaction.

  12. Re:You cannot be serious by Layzej · · Score: 2

    "A new study shows that the increase of atmospheric carbon dioxide that contributed to the end of the last ice age more than 10,000 years ago "

    Yeah, sure it did... evidence?

    CO2 is a greenhouse gas. That's just physics. If atmospheric greenhouse gas increased (and it looks like it did) then it necessarily contributed to the end of the last ice age.