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Science

Volcanic Warming Eyed in 'Great Dying' 353

Posted by michael from the learning-from-history,-hopefully dept.
gollum123 writes "AP writes on an article in the journal Science where an ancient version of global warming may have been to blame for the greatest mass extinction in Earth's history. 'In an event known as the "Great Dying," some 250 million years ago, 90 percent of all marine life and nearly three-quarters of land-based plants and animals went extinct. Researchers think the answer is Massive volcanic flows in what is now Siberia, and believe the extinctions were caused by global warming and oxygen deprivation over long periods of time."
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Volcanic Warming Eyed in 'Great Dying' More

Volcanic Warming Eyed in 'Great Dying'

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  • I knew it... (Score:5, Funny)

    by Anonymous Coward on Friday January 21, 2005 @10:31AM (#11431374)
    I should have never given Dick Cheney that time machine. I was not aware of the mischief he was capable of.

  • 16% oxygen? (Score:2, Insightful)

    by chris09876 ( 643289 )
    When people climb tall mountains, they have to deal with lower oxygen. (Some people bring oxygen with them, but some don't). ...16% oxygen in the atmosphere doesn't sound like it would kill all those people... I would have thought people/dinosaurs/creaturse would have learned to just live with the lower oxygen levels by subconsciously taking more breaths... (but I'm not a biology person)

    • Re:16% oxygen? (Score:4, Insightful)

      by garcia ( 6573 ) * on Friday January 21, 2005 @10:36AM (#11431439)
      When people climb tall mountains, they have to deal with lower oxygen. (Some people bring oxygen with them, but some don't). ...16% oxygen in the atmosphere doesn't sound like it would kill all those people...

      It might not kill people who are trained to deal with the differences in the levels. For the elderly, for those that have weakened immune systems, and for young children these changes might have consequences.

      People train at altitude for months to get their bodies prepared for thin air. I have a feeling that dinosaurs might not have had the chance (or possibly even the evolutionary ability) to make those changes over a short period of time.
      • That's a good point about people needing to train at lower oxygen levels. ...but my impression from the article is that the oxygen rate didn't decrease in a day, but happened over a couple million years as a result of the global warming
        • but my impression from the article is that the oxygen rate didn't decrease in a day, but happened over a couple million years as a result of the global warming

          As I said they might have lacked the ability to adapt to the changes over that time frame.

        • Re:16% oxygen? (Score:2, Informative)

          by Wyatt Earp ( 1029 )
          It compressed the inhabitable area on the surface while that and other things were happening that effected the oceans, and at the same time we have contiental shifts greating deserts and squeezing out the shallow seas.

          It was a triple-witching hour for extictions.

          Time of widespread regression of the seas.
          Gymnosperms (seed plants) replaced many spore bearing plants.
          Widespread accumulation of evaporites. More of Permian salt deposits than of any other age
          Waters were hypersaline
          Mass extinction at the end of t
      • If I train in a low oxygen environment my body adapts or is custom to the low amount of oxygen. I'm not really undergoing any evolutionary changes am I?

      • This is the Great Dying, about 250 million years ago. The dinosaurs died out about 65 million years ago.

      • It might not kill people who are trained to deal with the differences in the levels. For the elderly, for those that have weakened immune systems, and for young children these changes might have consequences.

        But that isn't extinction.

        People train at altitude for months to get their bodies prepared for thin air. I have a feeling that dinosaurs might not have had the chance (or possibly even the evolutionary ability) to make those changes over a short period of time.

        Sherpas [wikipedia.org] LIVE at crazy altitudes, and

    • Re:16% oxygen? (Score:2, Insightful)

      by Anonymous Coward
      N.B., The perentage of oxygen in the atmosphere doesn't change with altitude; the barometric pressure does, which reduces the amount of oxygen you can get per breath.

      • Re:16% oxygen? (Score:3, Informative)

        by Atrax ( 249401 )
        OK. yeah. sort of right. for a given value of right.

        It's the equivalent of teaching newtonian gravity at high school so that later you can learn einsteinian gravity at university, and then demolish the whole thing in your PhD thesis.

        the fringes of the atmosphere are thinner in oxygen than the lower reaches. of course for practical purposes (Everest/Chomolungma) there's less difference in percentage than higher up, and pressure is the overriding factor.

        OK, OK, I'm Anal Retentive. sue me.
    • Those people are just going up for a short period of time. Try doing your day to day things holding your breath 80% of the time. You are not going to die from the lack of oxygen but you wouldn't be effective.
    • Lower Oxygen levels may not kill you, but higher Carbon Dioxide certainly can. The reason has to do with how lungs function. When you breathe, the partial pressure of Oxygen in your blood is lower than that in the atmosphere. Hence, Oxygen flows from the air you breathe into your blood. The reverse is true for Carbon Dioxide. It flows from the blood to the air because the air has a lower partial pressure of CO2 than the CO2 in the blood. If the CO2 content in the air is too high, you can't get rid of t
    • Actually no. Your metabolism slows down to the point that you can't maintain body temperature. While lack of oxygen doesn't help with decision making, most people die of the cold WAY before oxygen debt kicks in at altitude. (The blood of people who live at altitude actually develops a high concentration of hemoglobin to compensate, but there are upward limits of what this adapation can adjust for.)

      The other thing to remember is that tweaking the partial pressure of oxygen effects how well oxygen is absorb

    • I would have thought people/dinosaurs/creaturse would have learned to just live with the lower oxygen levels....

      They're talking about the die-off before the Dinosaurs, not after.

    • "Subconsciously taking more breaths"? That's pretty funny, no offense intended.

      If you want a sense of how a change like this could radically change favored adaptations, think about grazing mammals that evolved to take advantage of grasses. As grasses became more prevalent, animals who could eat grass well exploded in population. Big niches got to be dominated by some pretty mundane-seeming adaptations to the digestive process. Seems like a subtle edge, doesn't it?

      Reading the article, the folks making th

  • Teh (Score:5, Insightful)

    by JPelorat ( 5320 ) * on Friday January 21, 2005 @10:34AM (#11431418)
    From the learning-from-history dept??

    WTF are we supposed to learn from this, "Don't set the fucking volcanos off"?

    If only the US had signed the Krakatoa-Pompeii Treaty, we wouldn't be getting fucked to death by these massive volcanic flows!!
    • Whoever modded the parent as troll really is an idiot, or, perhaps, doesn't know what "Troll" means (of course, the two aren't mutually exclusive).

    • Re:Teh (Score:4, Interesting)

      by HiThere ( 15173 ) * <charleshixsn@@@earthlink...net> on Friday January 21, 2005 @06:22PM (#11436703)
      Well, one variation of the meteor impact idea has it that the Deccan Trapps (??) were on the opposite side of the world from the impact, and in a rather critical state. The meteor impacted (in Yucatan?) and the shock waves were focused through the earth (with the mantel temperature/density creating a lensing effect) onto them, setting them off. I don't remember whether or not they had already been going through a cycle of eruptions, but this set them all off at once. Violently. So you got fire, tsunami, and darkness all at once, quickly followed by freezing.

      According to this, most of those who lived through this process either lived in the arctic areas, and could adapt by moving towards the equator, or spent part of their life hibernating or encysted...and could do so out of season when necessary.

      I've never seen this complex proven, but it would certainly explain why both the meteor impact people and the volcano people keep coming up with good arguments.

  • All this time (Score:5, Funny)

    by Fr05t ( 69968 ) on Friday January 21, 2005 @10:35AM (#11431425)
    "90 percent of all marine life and nearly three-quarters of land-based plants and animals went extinct"

    And all this time I thought it was nine-tenths of all marine life, and 75% of land-based life that went extinct.

  • More like the "Great Baking" (Score:4, Funny)

    by GillBates0 ( 664202 ) on Friday January 21, 2005 @10:36AM (#11431431) Homepage Journal
    The good part is that once we get the earth sufficiently heated up, we won't have to cook anymore!

    Mmmm baked vegetable and meat medley.

    The sad part is that we'll be part of the main course....I'll have Geek au gratin please with a side of elephant home fries.

    • about the sig... the human body is composed of at least a trillion, upwards to anywhere near 10 trillion cells... noone has carefully cross-sectionend a human into individual cellular layers to count each cell so it's just a rough approximation but it's a hell of a lot more than a billion, that's for sure... a gopher has more than a billion cells, and I'm pretty sure someone has chopped up one of those to count each individual cell*...

      *= or just because they'd watched too many caddyshack movies in a row.

  • Yesterday we had the great freeze... (Score:5, Interesting)

    by bwcarty ( 660606 ) on Friday January 21, 2005 @10:38AM (#11431460)
    now we have the great dying.

    This bit o' work by Robert Frost seems appropriate now:

    Some say the world will end in fire,
    Some say in ice.
    From what I've tasted of desire
    I hold with those who favor fire.
    But if it had to perish twice,
    I think I know enough of hate
    To say that for destruction ice
    Is also great
    And would suffice

    Slashdot...News for Nerds. Stuff about death.

  • Ok, I RTFM... (Score:5, Interesting)

    by His name cannot be s ( 16831 ) on Friday January 21, 2005 @10:42AM (#11431507) Journal
    From the article:
    Studying a 1,000-foot thick section of exposed sediment, Ward's team found evidence of a gradual extinction over about 10 million years followed by a sharp increase in extinction rate that lasted another 5 million years.

    Huh?

    A Gradual extinction over 10 million years? Yeah, That's gradual all right.

    The best part is the "sharp" increase over five million more years. So what he's saying is that a hell of lot of stuff died over 15 million years? Wowfuck.

    If we've got 10 to 15 million years of fossil fuel to burn, I say screw it.

    "Dear? you can turn up the heat now"

    feh.

    • Re:Ok, I RTFM... (Score:5, Insightful)

      by GoofyBoy ( 44399 ) on Friday January 21, 2005 @10:48AM (#11431578) Journal
      Um ... these are in geological terms.

      30 miles/hour is fast or slow depending on what sort of transportation you are talking about (walking vs. car vs. jet plane). 10 million is sharp vs 1100 million.

    • At present, the more common position is that the majority of the extinctions occured during less than 1 million years. So by contrast, Ward's position is quite slow.

      Actually a number of scientists are arguing for two short pulses of extinction seperated by approximately 10 million years, with the second one being especially severe. So that would be consistent with Ward's time frame though not with his view of it being one extended event.

    • It doesn't mean it took 10 million years for one species to become extinct. I means over a 10 million year period, species were become extinct, as you go through the time period, less and less are left. Then for 5 million years the numbers of species surviving drops quickly.

      Unless some very drastic happens (humans hunt it to extinction), most species die out over time.

      I have no idea what you mean by "we've got 10 to 15 million years of fossil fuel to burn". This is sediment, not fuel. We don't have near

  • Vulcanism (Score:5, Informative)

    by Atrax ( 249401 ) on Friday January 21, 2005 @10:43AM (#11431519) Homepage Journal
    It's certainly not the first time Vulcanism* has been implicated in a mass extinction - the Deccan Traps [nodak.edu], for instance, have been implicated in the KT event that is thought to have wiped out the dinosaurs 65 Million Years ago. There's even a school of thought that says the Chicxulub [arizona.edu] event may have triggered a major convulsion in the Traps - double jeopardy, if you will.

    Except that the earth is only about 4000 years old and fossils were put there to test our faith, right?

    * I nearly typed 'vulvanism', but that's a different story.
    • If you would have stuck with vulvanism you could still be correct. Certainly, as a species, humans are doing many things that could lead to mass extinction. Ironically, an obsession with vulvanism is one of them.
  • Did dinosaurs drive cars and use cans of aerosal hair spray? How did global warming occur if it wasn't their fault? Must have been due to methane gas release (flatulence sp?).

    It certainly couldn't have been caused by nature...

  • The Earth may have had 10%s of CO2 until photosynthesis was underway and 1%s into the era of the dinosaurs (its .01%s now). This is determined from paleosoil chemistry and rock types. Its probably not too bad if it takes hundreds of thousands or millions of years to reach these levels. Life can adapt easily. Its a different case if only a few centuries or generations and much harder to adapt.
  • Nobody get outta here alive.

    Discuss.

  • There must be a scientific version of Andy Warhol's aphorism: "theres a new theory every fifteen minutes". Whether its geology, astronomy, or medicine they cant seem to agree on a story.

    Actually I am just being cynical. Some fields are finally showing convergence, such as cosmology where the evidence is starting to agree with each other. I suggest a lot of this "newest, greatest theory B.S." is publicity mongering by institutions trying get more grants.
    • Gee whiz - ya think?

      Remember how the new "Ice Age" was comming? That was brought to us by the same group of hippies screaming about "global warming"

      Until we get the political agendas out of mass media "Science", I ain't buying it
      • Sorry but the "Ice Age is coming" climatologists were distinctly a minority in the 70s even at the peak of their popularity in popular culture. Scientist change their minds because that's the way science works. You get new information and experiments and you attempt to understand it in the framework of current theories. If the current theories don't explain the new data, you develop new ones. This is opposed to religion which claims to have the one truth, even if it doesn't fit the experimental data.

  • Sounds like Yellowstone (Score:5, Informative)

    by InterStellaArtois ( 808931 ) on Friday January 21, 2005 @10:58AM (#11431685) Homepage
    This is interesting, as just last night I was reading about something similar in Bill Bryson's "A Short History of Nearly Everything" ...

    To summarise, Nebraska is well known for its ash deposits - mined for cleaning products like Ajax - but no-one knew where it all came from.

    Then in 1971, Mike Voorhies found a mass grave of prehistoric bones - sabre-toothed deer, zebra-like horses etc. - all killed by something big 12 million years ago. They were all buried under volcanic ash up to 3 metres deep.

    One problem - no-one knew where all the ash came from.

    Now Yellowstone was known to be pretty active, with its geysers, boiling mud-pools etc. but they couldn't find a caldera, ie. an actual volcano cone anywhere in the park.

    But fortunately NASA were testing some high altitude photography techniques and decided to take some pictures of Yellowstone, thoughtfully dropping some copies off at the Visitor Centre. It was then that they realised that in fact Yellowstone is ONE BIG CALDERA - i.e. a 'superplume', 9000 square kilometres of crater left from some humungous explosion a long time back.

    In Bill Bryson's words, "imagine a pile of TNT about the size of an English county and reaching 13 kilometres into the sky, to about the height of the highest cirrus clouds, and you have some idea of what visitors to Yellowstone are shuffling about on top of".

    He goes on, "The Yellowstone eruption of two million years ago put out enough ash to bury New York State to a depth of 20 metres ..."

    And then there's the last supervolcano eruption in Toba, in northern Sumatra, 74,000 years ago. Studies of ice cores in Greenland show that at least 6 years of 'volcanic winter' followed, and that humans probably were at the brink of extinction, with maybe only several thousand of us at any one time for thousands of years after (which maybe explains our relative lack of genetic diversity).

    Yes, volcanoes are more than fire and magma - every now and then there're some *really* big ones.

  • Forgive me if this is off-topic, but does any geologist here know why we have volcanic flows whereas when we refer to icebergs we have floes. The reason for the spelling difference isn't immediately apparent in any of the dictionaries.

    I'm a graduate student, forgive me for this triviata.
    • Simple. Ice Floe is a term the Norwegians used to descibe thick chunks of ice. That's just their word for it, and it was so helpful we used it verbatim.

      Linq [peacelink.de]

    • Re:Flow v. Floe (Score:4, Informative)

      by Xilman ( 191715 ) on Friday January 21, 2005 @11:34AM (#11432084) Homepage Journal
      Forgive me if this is off-topic, but does any geologist here know why we have volcanic flows whereas when we refer to icebergs we have floes. The reason for the spelling difference isn't immediately apparent in any of the dictionaries.

      According to Chambers Dictionary, floe is probably from the Norwegian flo, meaning layer. The Old Norse is flO. The O character should really be a lower-case 'o' with an overbar, or a long-o, but that's not easy to represent here.

      Flow is a noun in Scottish, meaning a morasse, a flat moist tract of land, a quicksand, a moorland pool, a sea basin or sound. This one is from a slightly different Old Norse root, though rather similar to the previous. The Old Norse is flOa, meaning to flood, with Icelandic flOi, a marshy moor, and Norwegian dialect floe, a pool in a swamp.

      In Old English, the verb to flow, as appears in your example, was flOwan. I believe that the connection with this and the Scottish noun is through the Old Norse verb.

      Paul

  • Change in oxygen levels (Score:5, Interesting)

    by dragons_flight ( 515217 ) on Friday January 21, 2005 @11:00AM (#11431703) Homepage
    It is not obvious to me that changing oxygen levels would be all that destructive. We've known for a while that oxygen levels in the Triassic (following the "Great Dying") where some of the lowest in Earth's history. We have also known that oxygen concentration in the Carboniferous (50-100 Myr earlier) were some of the highest (perhaps 180% of modern value).

    In the Carboniferous, what you see (in addition to extra nasty forest fires) is an explosion of gigantism among diffusion limited organisms. Such organisms, mostly insects and amphibans, have respiratory or circulatory systems that are limited by the ability of oxygen to diffuse through them. With higher O2 levels, such animals can develop larger body plans and clearly did in the Carboniferous. By contrast, falling O2 levels would probably be an evolutionary pressure towards dwarfism and smaller body plans.

    After the Permian mass extinctions, we do see very few large animals. This might be associated with low O2 levels, but it might also be the results of an ecosystem so disrupted that it can't support large predators.

    However, it would be hard to hang the extinctions on oxygen alone since oxygen levels seem to have fallened over a much longer period of time than the extinctions, and would not have affected all organisms equally. Perhaps coupled with volcanism and global warming it is enough, but personally I doubt it. I am inclined to favor models that talk about volcanism or other causes leading to stratification and toxicity in the oceans. If you are going to kill >90% of all oceanic species, it would seem that the best bet is to make the oceans unlivable for them.

    However, this debate is likely to continue for a long time and we will no doubt hear many other theories before it is all done.
  • The "great dying" was caused by the meltdown of the core reactors of the ships that brought the ancient astronauts to the Earth. This meltdown happened because the ancient astronauts had a near-religious belief in closed-source system architecture and software that by default had very poor security.

    The few ancient astronaut advocates of the "open-source secure spacing initiative" were thought to have been killed as well, but what really happened was that they left the Earth, and colonized Titan (hence the

    • The "great dying" was caused by the meltdown of the core reactors of the ships that brought the ancient astronauts to the Earth.

      You are close, but it was no accident. God sabotaged the reactor with a bobby pin because she was mad at the astronauts for eating pork rinds (and Bill Gates paid her a bonus to do it).

  • Could you imagine if earth became like Planet Spaceball [imdb.com], with our leaders denying there's a lack of Oxygen while taking big gulps of branded bottled oxygen "PerriAir"?

  • Getting ridiculous (Score:3, Insightful)

    by bryan1945 ( 301828 ) on Friday January 21, 2005 @11:14AM (#11431849) Journal
    The average temperature during the dino age was 3-5 degrees above what it is now; they seemed to take it ok. Now we are going to blame a big volcano for global warming? How about the ash it would put up and block sunlight (hmm, cooling) and cause respiratory problems. How about all the great gasses it released, such as CO2, SO2, and whatever else volcanos belch up.

    I do not disagree that the planet may be getting warmer, but labeling an ancient volcano as killing off most life as global warming is just sensationalistic. The crap that is getting put out as "science" when it comes to global warming is starting to push the fringe of being reasonable. Didn't some guy say that we should all stop eating meat so we cull most of the cows so their methane gasses would no longer contribute to greenhouse gasses?

    This place is getting nuts, and I haven't found any Vogon ships recently.

    • Re:Getting ridiculous (Score:4, Informative)

      by ahunter ( 48990 ) on Friday January 21, 2005 @01:26PM (#11433334)
      Er, the parent post is so ignorant I don't even know where to begin.

      Let's see...

      1. Relevance to 'modern' global warming: none. This is a hypothesis to explain one of the biggest extinctions in the history of the planet. Whatever caused it, afterwards the planet was almost a complete desert.

      2. The siberian volcano wasn't merely 'big'. It was the size of Europe! One of the biggest volcanoes to happen since life evolved on Earth. And it lasted a very long time: erupting pretty much constantly for a million years. Krakatoa wasn't even a damp fart in comparison, and it changed the climate for years. It's called a flood basalt eruption, and they are really rare.

      3. We know something happened to the oxygen levels at that time. They've never recovered: before the extinction, oxygen levels were nearly double what we have now. Afterwards, oxygen levels were as low as they are now at the top of high mountains. Modern animals, including us, would have serious problems in that environment. Imagine what problems animals used to even more oxygen would have. Yep, they'd die.

      4. The dinosaurs. Yes. Well. Guess which event preceded the dinosaurs? You don't suppose, perchance, that the reason the world was warmer when the dinosaurs were about was because of this? I mean, saying the dinosaurs were happy in a hotter climate, so it doesn't matter if it's hot is just dumb. The hot climate that the dinos lived in was what killed the creatures that came before. That made space for dinosaurs to appear.

      Or to put it another way. Polar bears are perfectly happy when the temperature is -20 or lower. So naturally, everything else would be happy if the entire world was at this temperature. Yeah, right. (And of course, polar bears would be just fine living at the equator. The dinosaurs had it hotter! SHEEEESH)

      5. The main cause of the fall in oxygen levels was supposedly a massive drop in sea levels. The most likely cause of this is supposedly global cooling caused by the volcanoes ash (there are very large carbon deposits under the sea, which would have become liberated when the sea levels dropped enough). This is what caused the global warming.

      Finally, this is not sensationalistic. This huge extinction HAPPENED. The siberian volcano also happened, at the same time. The reduction in oxygen levels happened, too. A lot of other stuff happened at this time. There's very good evidence for all of this. The question the paper is trying to answer is what caused the extinction. This has bugger-all to do with global warming in a modern context, cows or even vogons.

      This [bris.ac.uk] link describes the vulcanism in Siberia a bit better than the rather lame Yahoo article linked by the blurb.

  • From the article:

    nearly three-quarters of land-based plants and animals went extinct.

    Plants do photosynthesis, consuming carbon dioxide and producing oxygen. Why would a decline in oxygen levels kill them?

    And something else: we humans have adapted to thin-air conditions quite easily. People live in Nepal and Tibet, and it did not even take evolution. Ordinary flatlanders can move to Tibet, too, and after a couple of weeks they have adapted to the thinner air. We are mammals, with big brains and a high m

  • And all the other scarecrows? 90% of today's leading scientists agree, that it is impossible.

    There must've been some other "evil multinationals" back then. May be, those dinosaurs had a more advanced civilization, than thought?

  • I thought bush said it was the Libral Homo-agenda leading Communists that would lead to the mass dying.

    I trusted him!

    Oh wait... he's not a scientist. He's not even what most would consider a "smart" individual. He's just another stupid US president. /sarcasm

  • "Noah was here." (Score:3, Funny)

    by enigmals1 ( 667526 ) on Friday January 21, 2005 @12:48PM (#11432944)
    We Christians called it "the flood"...and it wasn't 250 mil. years ago.

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