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Science

Volcanic Warming Eyed in 'Great Dying' 353

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'

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  • by Anonymous Coward on Friday January 21, 2005 @10:37AM (#11431452)
    Difference there is that Bush can help do something about global warming, but is too content keeping the petrol companies satisfied (and his pocket lined) to care about the bigger implications and the impact on the rest of the world. For a president who claims he has global interests at heart, it seems to be a particularly limited spread of interests.

    Ancient global warming was obviously unavoidable.
  • 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:[OT] Your .sig (Score:0, Interesting)

    by Anonymous Coward on Friday January 21, 2005 @10:54AM (#11431643)
    Luck is the residue of design -- Branch Rickey
  • by Engineer-Poet ( 795260 ) on Friday January 21, 2005 @10:58AM (#11431690) Homepage Journal
    The picture is quite a bit more complicated than that: when science provides so many facts (so much "truth"), it appears that human nature's "confirmation bias" leads people to entrench their positions based on the selection of those facts which support what they want. (You might notice the absence of such entrenched interests regarding asteroid strikes.)

    I suggest you read the papers here [cspo.org] and here [cspo.org] before continuing. Actually, I suggest that EVERYONE ON SLASHDOT read those papers; they will open your eyes.

  • 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.
  • by Engineer-Poet ( 795260 ) on Friday January 21, 2005 @11:10AM (#11431795) Homepage Journal
    There are human populations living at altitudes where the partial pressure of oxygen is about half that at sea level (Peru [uic.edu], Tibet [case.edu]). Even more interesting, the two populations seem to have two different adaptations to the altitude and there may be another adaptation original to Ethiopia [cwru.edu]. I doubt that we'd have any difficulty engineering ourselves with the physiological changes required to handle such conditions even if they occurred over the next century.

    The rest of the ecosystem would probably not be so flexible.

  • Re:Proves once again (Score:3, Interesting)

    by Illserve ( 56215 ) on Friday January 21, 2005 @11:27AM (#11432003)
    And yet, postulating the existence of an entire civilization based on absolutely zero evidence is kind of... pointless. At least in the God-existance debate we have spiritual texts.

  • by north.coaster ( 136450 ) on Friday January 21, 2005 @11:38AM (#11432132) Homepage

    Tim Cahill discusses this in his short book Lost in My Own Backyard : A Walk in Yellowstone National Park [amazon.com] (which is a great book, BTW). The Yellowstone caldera is believed to be 30+ miles wide. It has exploded several times, and in more recent times has been erupting about once every 600K years. The fact that the last explosion was 640K years ago can lead to some sobering thoughts.

    Some claim that the next eruption is overdue, a fact that the USGS disputes [usgs.gov].

  • by Mant ( 578427 ) on Friday January 21, 2005 @11:52AM (#11432291) Homepage

    Global warming definitely happens naturally. That doesn't mean the current global warming is natural, or entirely natural, or that we can do nothing to stop it.

    The consensus of scientific opinion seems to be moving more and more towards the current warming happening much faster than historical ones, and mankind being partially responsible.

    Problem is, by the time we wait for conclusive evidence, it may be too late.

  • Re:Proves once again (Score:1, Interesting)

    by Anonymous Coward on Friday January 21, 2005 @12:03PM (#11432413)
    it will outlast humans by a long shot, nothing we will do will kill it

    Earth will probably outlast anatomically modern humans, but what we could become may outlast it.

    Even better, what we could become might preserve it; make the solar system something of a national park. Keep feeding the sun fuel so it doesn't go poof.

    And why not? Is that too far out there?

    Well lets compare humans to the other lifeforms of this planet. The most powerful individual animal on the planet would probably be the blue whale (maybe some dinosaur as well, but we speculate much more about them)- in order of how many kilograms it as an individual could heft.

    Now lets take a human animal, by comparison we can lift only a small fraction of what the whale can lift. However, lets take a look at the most powerful thing a human has ever created...oh, say...a hydrogen bomb - just humor me.

    How many times more powerful than the strength of a blue whale is an individual megaton hydrogen bomb?

    And how much water can that whale displace? compare that to the aqueducts and dams from the ancients until today.

    I think it can be simplified to the concept of leverage. with a big enough lever you can lift the world.

    Humans are much more than the sum of their parts. we are an example of the exponential nature of intelligence. We are in fact only a small part the body in which we inhabit.

    What this power granted to us is used for is the question. But I think compared to the anchients we are making positive progress.
  • Re:Vulcanism (Score:2, Interesting)

    by CODiNE ( 27417 ) on Friday January 21, 2005 @12:29PM (#11432719) Homepage
    Except that the earth is only about 4000 years old and fossils were put there to test our faith, right?

    Only if you're a fundie.

    If however you HAVE been taught such a thing, or similar... there's a few scriptural points you may want to consider.

    1) A "day" in the bible can sometimes mean different spans of time.

    Even in modern English we use the word day in a figurative sense. "Why back in MY day we didn't do things that way." I'm sure you can think of many other examples. Just quickly using the KJV here (because I know it's pretty well accepted) Gen.2:4 says, "These are the generations of the heavens and of the earth when they were created, in the day that the LORD God made the earth and the heavens" So which was it? The earth made in 6 days or one day? Clearly the term day was not meant to be taken literally here, if you insist that it is literal, then you have to explain an apparent contradiction... the answer would be that one of them was figurative and all the rest literal.

    Also an interesting point came to mind since the parent poster chose 4,000 years as how long we've supposedly been on earth. As far as I was aware most people who believe in a literal 6 days of creation believe that we've been around just a bit over 6,000 years not 4,000 years. Of course he's probably remembering roughly 4,000 years of biblical history before Jesus was born. That 6,000 year time period and some scriptures I can't remember at the moment (ya know "1 day is for God 1,000 years and 1,000 years but a day") leads some to believe that we are now nearing the seventh "day" of earthly creation which would be a time of rest and peace on the earth. You may or may not think that's relevant, I just figured it was kind of interesting and related to the topic of "days".

    Another point related to days is... by what sense of time is God governed? Prior to creating the physical universe we live in, the scriptures say that heaven and the angels were already around... so what sense of time did they go by? 24-hour earth days? In a place where the sun never sets so to speak? Bazillions of angels who never sleep? A God who never tires? It seems unlikely.

    2) Heb.6:18 "it is impossible for God to lie". James 1:13 depending on your bible it is either "God does not put people to the test" or "He himself tempts no one" I'm paraphrasing here since the sentence structure varies. My point is... God is not a deceiver, he would not purposely set his own creation up in a way that would contradict his own teachings.

    3) The devil did it! Okaaay... you mean before he actually rebelled against God by inciting Adam and Eve to eat some of the forbidden fruit? The very act that got A & E kicked out of the garden permanently? Or was it after this that he made all those fake fossils? I just get the feeling that if he made the bones first he wouldn't have had access to A&E. Besides this... you REALLY should study the fossil record more since it actually supports your faith quite well since it basically aligns with the idea of creation much better than the idea of slow change in animals over millions of years. There's been many distinguished scientists, who were also evolutionists who admitted that the fossil record did NOT (at least then) support their views. Shouldn't we be curious as to their findings? Christians involved in science is a good thing... it helps keep the common theories based on fact rather than conjecture. Many would like to see overwhelming evidence for their belief in evolution but it just hasn't happened yet. Wouldn't it be a good idea to scrutinize and verify their findings? That would really help BOTH sides since we both want to know the truth.

    4) Faith is based on knowledge. Heb.11:1 "Now faith is the substance of things hoped for, the evidence of things not seen." If you have a copy of Strong's or Vines... take a look at the meaning of those two words "substance" and "evidence" that are in other translations may be "as
  • by Gar the Great ( 852060 ) on Friday January 21, 2005 @01:43PM (#11433512) Homepage
    So we know the ferocious potential of lava flows now. Why can't we use active lava domes to destroy nuclear waste? Wouldn't that do the trick? I always wondered this, but was too afraid to ask the teacher for fear of being laughed at. Sad, I know, but does anybody know the potential for this type of thing?
  • 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.

Remember, UNIX spelled backwards is XINU. -- Mt.

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