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Science

A New Ice Age? 449

Posted by michael
from the it's-all-fun-and-game-until-it's-too-late dept.
barakn writes "Scientists have savaged the new movie The Day After Tomorrow, which depicts global warming causing a new ice age and freezing New York solid. The movie follows on the heels of a report to the Department of Defense in February, written by two guys who are not climatologists, about the implications of global warming triggering the growth of ice sheets in the northern hemisphere. There is a plausible theory which suggests that melting ice may release enough fresh water to halt circulation of warm water from the Gulf Stream, thus significantly cooling Europe and the east coast of North America. Note that this theory depends on melting ice, not growing ice, which may be one reason scientists find the ice age scenario so hard to swallow. New satellite evidence suggests a part of this circulation may already be slowing down. Those on the North American west coast will not have to worry about ice sheets, but changes in Arctic ice could mean the western drought will be permanent. For those of you who would rather do something before it's too late, iron seems to work, but the long-term ecological implications are still unknown."
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A New Ice Age?

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  • by Amiga Lover (708890) on Saturday April 17, 2004 @08:05AM (#8890952)
    Wait... so you're telling me that a movie writer is being loose with the truth?

    What is the world coming to!?
    • by mabinogi (74033) on Saturday April 17, 2004 @08:07AM (#8890960) Homepage
      Actually, that makes me wonder if he was actually too close to the mark for the scientists to handle...

      You don't see scientists getting up in arms about movies like The Core, or Armageddon so why are they all defensive about this one?
      • by Ralconte (599174) on Saturday April 17, 2004 @08:09AM (#8890969)
        Ah, movie science, so you haven't been here, have you? http://www.intuitor.com/moviephysics/
        • I think some people have a hard time seperating science fiction from science fact as science fiction slowly becomes science fact (at least in hard sci-fi as opposed to science that's been twisted to be implausible by dramatic licence).
        • by PHPhD2B (675590) on Saturday April 17, 2004 @09:23AM (#8891243)
          Ah yes, the intuitor guy. An engineer* who seems to wish he's a scientist. And instead of educating himself further he puts up a web site with some equations (mostly 7th-11th grade physics ones) and keeps talking in "I don't think a real scientist would ..."

          And his silly attempts at savagery shows that he never quite GETS it - check out his "review" of The Core. It completely has eluded him that "The Core" is a funny little 50s type sci-fi movie, not a documentary.

          * I'm an engineer myself but I've been trained to actually find the truth, not make surmises about what I *think* scientists would say our do - I'd go ask some of them!

          • > Ah yes, the intuitor guy. An engineer* who seems to wish he's a scientist.

            The thing I find ironic with people who complain about how movies are unrealistic, is that they never seem to stop to think "This *movie* is unrealistic." It's SurReal to begin with! The Movie isn't real - so why aren't they complaining about that?!

            Oh wait, what they *really* mean, is that their suspension of disbeleif wasn't maintained. For Christ's sake already -- Movies were made to be enjoyed -- Do you *really* need to
      • by Teppy (105859) * on Saturday April 17, 2004 @08:12AM (#8890984) Homepage
        Scientists are up in arms because this movie was written by paranormal talk show host Art Bell [coasttocoastam.com] and alien abductee Whitley Strieber [unknowncountry.com].
      • by WIAKywbfatw (307557) on Saturday April 17, 2004 @08:17AM (#8891002) Journal
        Maybe because climate change caused by global warming is potentially (note, I said potentially) a man-made disaster waiting to happen, whereas drilling down to the Earth's core isn't actually happening and being hit by an asteroid the size of Texas is highly unlikely for the immediate future.

        The attitude of a lot of people here on Slashdot with regards to global warming amazes me. This is something that could possibly devastate society as we know it, perhaps not for us, but for our children or our children's children, but there's a great many people who either dismiss it as never going to happen or something that can be easily controlled without any major shifts in lifestyle or attitude.

        Someone once said "This is a fragile ball we're living on. It's a miracle and we're destroying it." That's a hell of a lot closer to the truth than any politician, especially any politician who's made a killing from exploiting fossil fuels, will ever admit to.
        • by SerpentMage (13390) <ChristianHGross@ ... o.ca minus punct> on Saturday April 17, 2004 @08:27AM (#8891030)
          Sure global warming may be happening... BUT and this is probably why the slashdot people are laisse faire, maybe it is part of the overall scheme of things by none other than mother nature.

          When that little warming period and ice age hit, which was not caused by humanity, would the arguments not be the same? EG would the green people would be saying to stop burning all of those fires to heat homes?

          Frankly I think the only real way of stopping global warming is to kill off about 2/3 of our planet. There are just too many of us.

          Let me give you an example. Germany, which is trying to be green installed a huge number of wind powered generators in the North Sea. They have just found out that because of all those generators the coast is getting 10% more sunshine and 10% less rain. I then ask the question, are we not dammed if we do and dammed if we do not?

          So unless you are ready to volenteer your life in the name of "humanity" nothing much is going to change.

          BTW I do not agree with your quote as planet Earth has withstood worse things than humans and continued. What might not survive are the humans!
          • by bankman (136859) on Saturday April 17, 2004 @09:29AM (#8891268) Homepage
            BTW I do not agree with your quote as planet Earth has withstood worse things than humans and continued. What might not survive are the humans!

            Reminds me of Hoimar von Dittfurth who once said, and I paraphrase, that "mankind shouldn't be so arrogant to believe that it can destroy the earth. The earth will have destroyed us long before that." Like you, I completely agree.

          • by the argonaut (676260) on Saturday April 17, 2004 @09:42AM (#8891321) Homepage Journal
            BTW I do not agree with your quote as planet Earth has withstood worse things than humans and continued. What might not survive are the humans!

            Unfortunately, we seem to have the attitude that if we're going down, we're taking every other living thing with us.
          • by Tesla Tank (755530) on Saturday April 17, 2004 @10:33AM (#8891593)

            Although I agree with you that we don't know if global warming is suppose to happen right now anyway, the rate of change is what's alarming the scientists. Records going back hundreds of years give us a pretty good image of the weather pattern we're suppose to receive. The amount of extreme weather occurances and unprecedented warming of land inside the arctic circle is why scientists are concerned. The rate of change is simply beyond anything nature alone could do.

            So yes I do agree with you that globam warming and ice ages are normal. Maybe we're suppose to have global warming anyway. But the rate that this is happening is alarming. And it leaves us little time to prepare ourselves to find ways to adapt to the new climate.

            • by Anonymous Coward
              Remember that 30 years ago, we were all concerned about the next ice age. Global cooling was the fear. Then the conditions in the Pacific Ocean flipflopped in 1977 and we started warming. These flip flops occur roughly every 30 years or so (the previous ones were 1947 and 1923). The 1923 started warming, the 1947 one started cooling. The problem is that these circumstances occur over spans on the order of human lifetimes...
              • by Anonymous Coward on Saturday April 17, 2004 @12:08PM (#8892121)
                "Remember that 30 years ago, we were all concerned about the next ice age."

                This was something whipped up by the media. Global warming has been under discussion in the scientific community for about 100 years. (Yes, really). On the back of work on nuclear winter scenarios in the early 1970s there was some speculation that particulate matter from coal burning might cause a local cooling in some parts of the globe that would offset it. It is no longer believed that this is the case, and was only an possible theory for a brief period. However the media really grabbed onto the theory and keep bringing up.
  • It occurs to me... (Score:2, Interesting)

    by clifgriffin (676199)
    That every global warming prediction scientists have made in the last 30 years has fallen flat on its face.

    According to them, we should be all dead by now.

    Personally, I'm not sweating anything. There is plenty of evidence that our toxic output is not the largets or the deadliest on this planet, and thankfully things pretty much clean themselves.

    I refuse to forget how many times popular science has been wrong.
    • by Lumpy (12016) on Saturday April 17, 2004 @08:13AM (#8890991) Homepage
      I refuse to forget how many times popular science has been wrong.

      there is your answer... "popular science"

      it diesnt say accurate science, or proper science or even real science... but popular science...

      they only print that which is "popular" at that time. Many times their articles are complete bunk and sensationalized to the point of being redicilous... and they have ALWAYS been that way.

      Popular science is for the Lay person that likes to be entertained... go grab one of the real science journals for accurate information.
      • by Anonymous Coward
        It can't be "accurate science" or "proper science" or "real science" because there is no control, nor is there any way to run any experiments to actually measure any cause-and-effect relationships.

        Could the warnings of global warming armageddon be true? Yeah, but so could the warnings of global cooling armageddon from the 1970s.

        And even if either guess is true, there's no way to be sure that the problem was caused by man.

        Now, all that doesn't mean we shouldn't be reasonable about reducing pollution and gre

        • It can't be "accurate science" or "proper science" or "real science" because there is no control, nor is there any way to run any experiments to actually measure any cause-and-effect relationships.

          Wrong. While it is not possible to run experiments as such, it certainly is possible to make certain predictions based on the underlying physics and look how the predictions turn out based on empirical data. Then the theory is either validated or not - in which case you modify the theory trying to account for the difference. Or, in briefer terms, you apply the basic scientific process.

          And of course it is still absolutely possible to run many experiments on a smaller-than-global scale - the outcome of which help the understanding of the global climate and help predict it's future development.

          And even if either guess is true, there's no way to be sure that the problem was caused by man.

          That's true. There's no way to be sure of anything per se. There are ways to be reasonably sure of it based on a given set of information, though.

          Well, except if the older "global cooling" predictions were really true, then we should be cranking out the greenhouse gases, right?

          No. I haven't been around to read about the older predictions, so I might be wrong. However, I imagine a global warming can well induce a severe global cooling, and the other way round. And furthermore, it might well be that the previous claims were just wrong - and the underlying assumptions corrected since then in the process I described above. Of course, now you're saying "Well, what if they're wrong again?!" - that's just the problem with any scientific claim, it can always be wrong. Unless you've got some indications that the current theories are failing, though, it'd be probably be wise to assume they are correct. If on the other hand you do have such indications, you probably should do some research into the matter and find out if either you're wrong, or they are.

          And as for the original poster saying: "I refuse to forget how many times popular science has been wrong."

          I'm not sure what exactly "popular science" is supposed to refer to, but science is one of the few fields were being wrong is not that bad. Newton's laws on gravity have also been proven wrong, but they were still an incredibly important discovery. And while you refuse to forget how often science was wrong, you do seem to forget how often it has learned from those errors and corrected them, and how often science is right. Also: Try reading a book some day. [amazon.com]
      • by Smidge204 (605297) on Saturday April 17, 2004 @08:29AM (#8891035) Journal
        I don't think the parent was referring to the magazine "Popular Science" but rather the current theories that permeate society, eg: "Global warming" and "We only have 20 years worth of oil reserves left". (That second one was popular around the 1970's, and 30 years later they still say we have 20 years worth left...)

        Unfortunately, it's popular science that the laymen take as truth. The public has SO MUCH blind faith in science its disturbing. Everyone figures "well these guys are scientists, so they must know what they're talking about" - It's not that that the public is stupid (debatable...) but rather they are just so uninformed about how everything works that they really can't critique the claims.

        And all too often the laymen are the policy makers and social/political reactionaries. That's when the problems start.
        =Smidge=
        • by Bearpaw (13080) on Saturday April 17, 2004 @09:17AM (#8891217)
          I don't think the parent was referring to the magazine "Popular Science" but rather the current theories that permeate society, eg: "Global warming" and "We only have 20 years worth of oil reserves left". (That second one was popular around the 1970's, and 30 years later they still say we have 20 years worth left...)

          Your gross (though common) oversimplification of the claims doesn't counter the fact that the amount of oil is limited ... unless you are hypothesizing either an infinite amount of oil or some currently unknown process that is replacing it as fast as we can use it? When the reserves will run out, whether in 5 years or 50, is a relatively unimportant detail compared to the fact that they will. Yes, there is uncertainty about the timing -- should we gamble that it will be later rather than earlier?

          The attitude that "it hasn't happened yet therefore it won't happen" is even sloppier thinking than what you are criticizing.

          The only way to avoid be caught unprepared for changes in the availabilty in resources is to prepare for those changes. Why is this so hard to understand?

          • by Smidge204 (605297) on Saturday April 17, 2004 @12:04PM (#8892098) Journal
            Thanks for putting words in my mouth.

            My whole point, which you seemed to have completely glanced over during your little crusade, is that scientists make statements that the public in general doesn't completely understand. This half-knowledge scientific rhetoric then becomes so widespread throughout society it "becomes fact", when in reality it's only half the story.

            Did I ever say we'd never run out of oil? No. Did I say Global Warming is a myth? No. I never used the words "it hasn't happened yet therefore it won't happen." I think we both agree that's the worst attitude you can have in any situation. My point is that, in the 1970's, we knew we would "run out of oil in about 20 years", and today we know that global warming will destroy the planet as we know it in 10 years (or whatever they're saying nowadays). When in fact what we as a society know is really only half the story. However, it's "popular" that global warming is going to destroy the planet in our lifetimes, and that somehow makes it fact when it's really just one of many, many possibilities we don't fully understand.
            =Smidge=
    • by fw3 (523647) * on Saturday April 17, 2004 @09:23AM (#8891241) Homepage Journal
      That it's far too early to call whether these studies, models etc are going to be right / wrong. 'Prediction' is a dangerous business.

      Generally, in any case by no means every theory/prediction made about climate has been wrong. Case in point James Lovelock (who happens to be one of the two founders of what's generally known as the Gaia hypothesis) and co-researchers *accurately* predicted the medium-long term results of CFC release on the ozone layer.

      Science is inherently wrong, because it's the art of better explaining what we don't know. Another related case in point. Up until a dozen years ago physical oceanography uniformly concluded (based on theoretical models and very limited data sets) an understanding that the deep ocean flow was uniform and slow.

      A friend of mine at WHOI put some cameras on the floor of the northern Atlantic, one day they were thinking their hardware had flaked 'cause they couldn't see anything. What was happening was silt was being stirred up by a high velocity current. What they discovered was that oceans have 'weather patterns' which operate much as atmospheric weather, fronts, low&high pressure areas etc.

      This completely blew away established theories of physical oceanogrpahy (and happens to be directly related research to the abrupt climate change and ocean conveyor research article referenced in this post).

      I'm glad you feel safe, however concluding that you're safe because prior research has been wrong is not a great recipe for the long term. The CFC / ozone problem is one of the first instances of scientific results materially impacting environmental policy at the global/international level. If rapid-onset ice-age is a possiblity (this has been pretty well established). And if a 'lens' of low-density fresh water over the northern oceans can trigger this abrupt change we would be foolish to conclude there's no risk worth further understanding.

  • I'm not convinced (Score:2, Informative)

    by Omega037 (712939)
    I personally believe that all this supposed changes may eventually occur, but they are a normal cycle of the earth and be very gradual. If the human race mangaes to survive long enough, we will slowly change how we do things to meet these problems.

    Regardless though, what is gonna happen will happen, and there is nothing we can do to change it. Worrying about such things seems pointless to me. The whole planet is going to be destroyed by the sun dying in about 5 billion years, why don't we worry about
  • ice age (Score:4, Interesting)

    by marine_recon (652565) on Saturday April 17, 2004 @08:12AM (#8890982) Journal
    i might be wrong, but arnt people saying were in the middle of an ice age right now and the only thing keeping it check is the amount of CO2 being produced. anyone?
  • a comment (Score:3, Interesting)

    by cinnamon colbert (732724) on Saturday April 17, 2004 @08:13AM (#8890988) Journal
    A major part of climate change is the amount of CO2 in the air (CO2, carbon dioxide, is the major greenhouse gas) In figuring out how CO2 levels will change, a major term is the exchange between gas and water over the oceans; this is a key parameter in all the super complicated computer models from places like NOAA a few years ago, in SCIENCE magazine, turns out this term was wrong by an order of magnitude CONCLUSION: the models are crap why ? u r an administrator, testifying before congress on why u need 200 large. YOu could say, well we made major progress in FFT algorythmns usefull in modeling, and our understanding of image recognition to model cloud patterns...(congress falling asleep) OR u cd say GLOBAL WARMING !!! NYC underwater !!!! it is not that it is bad science, it is just that the quality of the models is not that high - noone has the lsightest idea of how our climate will change in response to any significant perturbation - sort a like MS stuff, no ?
    • by pjt33 (739471) on Saturday April 17, 2004 @08:42AM (#8891079)
      Could the person who modded parent informative please translate it into English? (Spanish or French will do, I'm not too fussy).
      • by bhima (46039) <Bhima.Pandava@gma i l . com> on Saturday April 17, 2004 @09:07AM (#8891169) Journal
        Una parte importante de cambio del clima es la cantidad de CO2 en el aire (el CO2, bióxido de carbono, es el gas principal del invernadero) en calcular fuera de cómo los niveles del CO2 cambiarán, un término importante es el intercambio entre el gas y el agua sobre los océanos; esto es un parámetro dominante en todos los modelos complicados estupendos de la computadora de lugares como NOAA hace algunos años, en compartimiento de la CIENCIA, resulta este término era incorrecto por una orden de la CONCLUSIÓN de la magnitud: los modelos son crap porqué? u r un administrador, atestiguando antes de congreso encendido porqué necesidad 200 de u grande. Usted podría decir, bien hicimos progreso importante en usefull de los algorythmns de FFT en modelar, y nuestra comprensión del reconocimiento de la imagen para modelar caer de los (congress de los patrones de la nube... dormido) O CALENTARSE GLOBAL de la opinión "copia más oscura"de u!!! cNyc subacuático!!!! no es que es mala ciencia, él es justo que la calidad de los modelos no es que alto - noone tiene la idea ma's lsightest de cómo nuestro clima cambiará en respuesta a cualquier perturbación significativa - clasifique a como la materia del MS, no?
  • by ZeNTuRe (771486) <zenture AT hotmail DOT com> on Saturday April 17, 2004 @08:13AM (#8890989)
    There will be no need for the upcoming 2Kg heatsinks.
  • by Mahonrimoriancumer (302464) on Saturday April 17, 2004 @08:13AM (#8890992) Homepage
    Next you'll be telling me that Jurrasic Park, Armageddon, etc. are based on junk science!
  • by Anonymous Coward on Saturday April 17, 2004 @08:15AM (#8890996)
    IIRC, the historic/geologic average temperature of the Earth over it's 5-billion or so years had been something like 72 degrees F.

    Today, it's like 59 degreees F.

    If that recollection is true, then we're still in an "Ice Age" and should expect the world to be getting warmer if the "Ice Age" is in fact coming to an end.

    Sorry if this doesn't fit into the "human == BAD, all_natural == GOOD" paradigm, but getting struck by lightning or eaten by a lion does fall into the "all_natural" category too...

    • Unless you're eaten by a white lion [bbc.co.uk] which is only alive because we want to gawk at them....

      Also, does a lightning strike still count as all_natural if you're out playing golf in a thunderstorm? :o)

      Totally agree with you on the global warming [globalwarming.org] though...
    • by eclectro (227083) on Saturday April 17, 2004 @09:04AM (#8891155)
      If that recollection is true, then we're still in an "Ice Age" and should expect the world to be getting warmer if the "Ice Age" is in fact coming to an end

      This is what I call "Dubya" science or speak, as this is something like what he would say.

      The fact is that we are conducting a worldwide uncontrolled experiment on mother earth, as we pump evermore quantities of CO2 in the enviroment.

      There has never been a greater amount of CO2 in the enviroment than right at this point of time.

      This outpouring of uncontrolled CO2 started with the industrial revolution and hasn't slowed since.

      Likewise, the temperature of the Earth has been rising steadily and at a faster rate.

      People may scoff at and dismiss a 1 degree raise in the earth temperature as nothing important, but there is one fact of physics that is incontrovertible;

      Ice is frozen at 32 degrees, ice is *water* at 33 degrees

      Which means that we start losing the polar ice caps with a one degree change in the earth's climate.

      Startling evidence has occured that this shows this very thing may be happening - The north pole turns to water on a regular basis, and a huge part of the Antartic ice sheet has broken off.

      I'll let somebody else post the links or google it. One of them was an old slashdot story.

      So scientists or whoever can diss the movie all they want, but it is just a matter of time before some weather related event occurs that will come back to bite us in the collective but in a big way due to global warming.
      • by protolith (619345) on Saturday April 17, 2004 @07:52PM (#8894738)
        "There has never been a greater amount of CO2 in the enviroment than right at this point of time."

        This is complete bullshit! The current CO2 concentrations in the atmosphere are on the order of 12%. Global climate predictive models (calibrated with painfully short term datasets) deal with CO2 or "double CO2" concentrations. An examination of geologic evidence indicates that CO2 concentrations have been historically as high as 60% during the Cambrian (ended 540 mya) and CO2 concentrations were this high until the carboniferous (Mississippian and Pennsylvanian) when land plants began to cover the globe.

        "This outpouring of uncontrolled CO2 started with the industrial revolution and hasn't slowed since."

        An enormous amount of CO2 was sequestered in the Proterozoic and Paleozoic in the form of marine deposited carbonate rocks (limestone CaCO3) and most of the worlds coal was deposited in the Mississippian and Pennsylvanian. The burning of fossil fuels is only circumvention of the carbon cycle, where these carbon sinks would otherwise be subducted and released through volcanic activity this process of recycling has been going on for millions of years. The sum total of ALL INDUSTRIAL ACTIVITY is akin to a few more active volcanoes on the world.
        The CO2 emissions according to this site http://www.ucsusa.org/global_environment/global_wa rming/page.cfm?pageID=965 For the last 245 years for the top 20 industrialized countries are roughly half of the CO2 emissions of the 12 most currently active volcanoes
        9581925304 M tons in 245 years - volcanoes 4960020000-M tons in 245 years -Industrial Countries
        http://www.ees.nmt.edu/Geop/mevo/geochem/co2.html

        As it can be seen Baseline volcanic activity exceeds Industrial activity this is without consideration of all of the large volcanic eruptions in the last 245 years.
        According to geologic record in reference to glaciation and ice ages, before the most recent 3.5 million years of ICE ages the earths average temperature was estimated to be warmer than it is now (Based on fossil locations that point to climatic conditions for given locations) there were also interglacial periods where the average temperature of the earth was warmer than it is now. There is every bit of geologic indication that the earth should be warming as it is. Even fluctuations in solar intensity (released from the sun) coincide with warming and cooling periods.

        The real problem is that in the case of climate research there is far less funding for the people that are pointing out that ITS ALL PART OF THE RIDE, than the people that want to scream that we are all going to die!
    • by sparks (7204) <acrawford&laetabilis,com> on Saturday April 17, 2004 @10:16AM (#8891511) Homepage
      Absolutely correct, we are at present still in an ice age which has lasted for about four million years, with (geologically) brief "interglacials" of around 10,000 - 20,000 years every 140,000 years or so.

      We are in one of one of those interglacials now, and in fact it has lasted 18,000 years so far - so it's not at all crazy to start looking for signs of the end of it.

      This is not the first ice age; there one approx 600 million years ago; another 450 mya; another 300 mya. They each lasted at least a few tens of millions of years. This ice age is young and will likely exist for many millions more years. During this whole time, we can expect the glacial and interglacial cycle to continue.

      There are some important points everyone who discusses climate should be aware of:

      For most of the history of the Earth, it has been very much warmer than it is now.

      For the last four million years, it has, on average, been very much colder than it is now.

      A thousand years ago, there was a "medieval warm period" during which global temperatures were significantly warmer than today; to the extent that wine grapes were grown in Southern Scotland.

      Five hundred years ago temperatures were significantly colder than today; "the little ice age". Opinions vary as to when the LIA ended; some say aruond 1900, others say it hasn't totally ended yet.

      Note that both the MWP and the LIA occurred before the industrial revolution; they were not caused by man.

      There is no "normal" temperature.

      The current climate has not existed very long, and will not stay the same for very long (and this would be true even if there were no humans).

      • It doesn't really matter....

        What matters is the comment "THERE IS NO NORMAL TEMPERATURE" (caps mine). Whether or not the climate gets a bit warmer or a bit colder, all hell is going to break loose because mankind is pushing the envelope of sustainability on the planet. With the population set to pushing ten billion in this century, it's not hard to find populations living very close to survival margins (a small shift in any major variable -food, water, temperature)will cause major stressors on the popula
  • by JaF893 (745419) on Saturday April 17, 2004 @08:19AM (#8891008) Journal
    Although accurate software models of the earth's climate and weather conditions don't exist. There is certainly the hardware to run it. The worlds most powerful supercomputer the Earth Simulator [jamstec.go.jp] is designed to be able to accurately model the earth. Hopefully advances in software modelling will enable us to actually make good use of all that raw processing power.
    • Not quite. The computer has massive computational power to be sure, but to accurately model the complexities of the earth would take alot (and I do mean ALOT) more power.

      They can make a better approximation. If it were used for weather, it could possibly give us a relatively accurate forecast for a couple of weeks (as opposed to a handful of days). :)

      The problem with simulating earth is that there are too many variables, and too much data. :)

      ~X~
      • The Earth simulator is not about predicting local short-term weather. That is way too dependent on random events to be easily predictable. The Earth simulator is about predicting the overall trend in weather patterns over years and decades. The goal is to find out, e.g., if we double the amount of CO2 over the next 10 years, will the average annual rainfall on the Mediterranean coast increase, decrease or stay the same? (and I mean, not the annual rainfall for 2017, but the average amount for the 2010s.)

        Lo
  • Terraforming (Score:3, Insightful)

    by Anonymous Coward on Saturday April 17, 2004 @08:22AM (#8891014)
    Why is it that people here* are so dismissive of climate change on Earth, but if it's terraforming on Mars, nary a criticism (of the scientific theory) is heard...

    * a generalisation, yes, but just look at some of the comments so far!
  • Well, damn! (Score:5, Funny)

    by Dark Lord Seth (584963) on Saturday April 17, 2004 @08:24AM (#8891017) Journal

    I was hoping for global warming! I already had ordered a few 100.000s tonnes of pearly white sand to make some lovely beaches in soon-to-be-sunny Greenland... Damn it!

  • by beaverfever (584714) on Saturday April 17, 2004 @08:25AM (#8891019) Homepage
    There is a plausible theory which suggests that melting ice may release enough fresh water to halt circulation of warm water from the Gulf Stream, thus significantly cooling Europe and the east coast of North America.

    okay, I couldn't begin to tell you where I heard this (let alone provide a URL) but I recall hearing/reading the "global warming=new ice age" theory kinda like this:

    So the earth's temperatures rise a certain level, really only a few degrees, maybe half a dozen. This means the atmosphere can hold more moisture and precipitation increases.

    But - with the earth's overall temps slightly higher the temperatures over the poles would still be hella cold (just not as hella cold as before) and the moisture-laden air passing over the cold regions would dump a lot of snow, sleet and ice, which would mean expanding polar ice caps, glaciers, etc., etc., albeit this would be a cumulative effect taking place over many thousands of years.

    So, like, I ain't no climatol... clima... uh, scientist or nuthin' - that's just what I read in some fancy magazine somewhere.
  • Bad Science (Score:4, Interesting)

    by Prototerm (762512) on Saturday April 17, 2004 @08:30AM (#8891040)
    A few months ago ( I can't find the link right now), scientists were claiming that "Global Warming" is not the problem the media, and some politicians say it is. According to the original Global Warning theory, the Earth's temperature is higher than it's ever been due to the influence of technology (greenhouse gasses). The scientists in this new study pointed out that the original Global Warming research ignored historical data documenting temperatures in Europe, in the Middle Ages, that were higher than today. It would appear that the original scientists chose a date range for their research that supported their already-made conclusion of Global Warming.

    It would seem that the Earth's climate is normal, and we're not going to suffer a slow broil (so put away the onions, and get that apple out of your mouth).

    As for the ice age theory, one of the last ice ages was caused by a lot of fresh water pouring into the North Atlantic. The difference in salinity caused the warm Gulf Stream waters to submerge, reducing the overall temperature in Europe and North America enough to cause an Ice Age. The effect took only 70 years.

    It would indeed be ironic, though, if the only way to save civilization as we know is would be to increase greenhouse gasses, not reduce them.

    • Re:Bad Science (Score:5, Interesting)

      by Gadzinka (256729) <rrw@hell.pl> on Saturday April 17, 2004 @08:57AM (#8891122) Journal
      ...one of the last ice ages was caused...

      I just wanted to remind you and everyone else, that we are living in the last Ice Age, it didn't end yet.

      The climat we are experiencing for the last 12000 years or so is a moderate warming during an Ice Age, nothing special. And yet all our civilisation was built in and depends on these rather uncommon (for this planet) conditions.
    • Re:Bad Science (Score:5, Interesting)

      by MtViewGuy (197597) on Saturday April 17, 2004 @09:02AM (#8891148)
      I think the global warming crowd is forgetting one thing: the biggest determinant of the climate on Earth is caused by this thermonuclear fireball about 93,000,000 miles away called the Sun.

      Since the 1600's when telescopes became widely available, scientists have actually plotted the level of sunspot activity. They noted that between the 17th and 18th Centuries there was a long period of NO sunspot activity, and that corresponded in a mini Ice Age period where temperatures in Europe were quite a bit lower than normal and the Thames River going through London regularly froze over during the winter.

      Indeed, I think Earth is returning to a period of warmer weather akin to what it was like before the dinosaurs died out about 65,000,000 years ago.
  • non-linear systems (Score:4, Insightful)

    by Transcendent (204992) on Saturday April 17, 2004 @08:40AM (#8891073)
    Note that this theory depends on melting ice, not growing ice, which may be one reason scientists find the ice age scenario so hard to swallow.

    Because our climate is probably not bound by a purely linear occurrence of events. It is full of rebounds, snap-backs, and whatever else you want to call it... like oscillations.

    Just because the melting of the caps is the result of global warming doesn't mean that doing so will not trigger a rebound, causing more of the northern hemisphere to freeze. Just like freezing the caps and lowering the sea level will (theoretically) uncover methane deposits in the soil, releasing greenhouse gasses and thus warming the planet again. So stopping the nice current bring warm water up to northern Europe will cool it down, allowing more ice caps to form. Sure, one they're formed the currents might start up again and warm up Europe, but like I said, it works in oscillations.

    What really surprises me is why so many people have a hard time swallowing this. Even looking back at the history of Earth's climate shows numerous ice ages and warm periods. CO2 levels have done the same as well.

    Some people just need to think a little bit longer down the line. Or maybe they disregard the claims so they don't loose grant money? Not flaming, just a warranted curiosity...
  • by Xerp (768138)
    Nature probably thinks we are spyware or something, and figures the only way to fix the problem is to do a "cold boot"...
  • YOU just try to explain that to Joe Average in 100 minutes!
    • by back_pages (600753) <{ten.xoc} {ta} {segap_kcab}> on Saturday April 17, 2004 @09:44AM (#8891336) Journal
      The History Channel or The Discovery Channel has a very revealing documentary on this topic exactly. It hardly even touches the topic of global warming. It carefully explains the deep ocean currents that run from the Atlantic NE around Africa to the Indian Ocean and around Australia to the S Pacific, and how this current circulates the Earth's water supply and regulates climates. It goes on to point out that these deep ocean currents travel at something like six inches per hour, and a water sample pulled from the bottom of the S Pacific can be dated to roughly 2000 years ago (based on atmospheric conditions and contaminants in the water.)

      This is a pretty strong argument that the higher lattitudes are temperate because of the regulating effects of the currents. Siberia is a frozen waste because it benefits from no nearby warm current, and the Sahara bakes while the Amazon is merely tropical because of the proximity to a regulating surface current. If the deep ocean current were disrupted, there is reasonable and significant doubt that a different suitable global ocean current system would develop to prevent the low lattitudes from turning into a planet-wide desert while the high lattitudes make Siberia look like a warm vacation spot.

      Then it demonstrates in a fish tank how cold water currents cannot descend in fresh water as well as in salt water. This is exactly what happens near Iceland, where the warm Atlantic surface current hits Arctic waters and drops to the ocean floor to fuel the deep ocean current. Already they have scientific measurements to suggest that the deep ocean current is being fueled less now than it was 30 years ago, before which nobody understood the importance of salinity in the oceans and the deep ocean currents. This correlates to the alarming increase in icebergs which have broken away from the polar ice caps over the last few decades (something like a 500% increase, by the way.)

      And the documentary takes only 60 minutes, including commercials.

  • The Great Conveyor (Score:3, Informative)

    by Anonymous Coward on Saturday April 17, 2004 @08:59AM (#8891128)
    Cold, salty water from the North Atlantic sinks far below and runs south. Far enough south that it brings back warmer waters north. This flow includes the Gulf Stream.

    Climate research has shown that climate shifts have occurred over history in as little as a few years.

    If enough ice melts and flows into the North Atlantic, it disrupts the cold saline flow, which disrupts the concomittent return warm flow. Which makes the Northern Hemisphere colder. Which brings on the Ice.

    That's as simple as it gets and the ice record in Greenland bears this out.
  • by Anonymous Coward on Saturday April 17, 2004 @09:08AM (#8891175)
    The real problem these movies point out is the shocking rise in bad acting. Apparently something in the future (possibly estrogen-like toxins?) is destroying humanity's ability to emote properly. This is what scientists should be studying. At the rate it is occurring, bad acting could sweep the planet in just a few decades. This could have a profound impact on Broadway, Shakespeare festivals, and even school plays.
  • Previous Ice Ages (Score:5, Insightful)

    by tehanu (682528) on Saturday April 17, 2004 @09:24AM (#8891246)
    I'm not sure how bunk the notion of Global Warming causing an ice age is (esp. since the article seems to be slashdotted so I can't read it) nor have I watched the movie. I remember when we were studying planetary science, one of the chief questions was what caused ice ages, esp. connections with the Earth's orbit and rotation. Mind you this was some years back, but if I recall correctly, one of the things we focused heavily on was the fact that the geological evidence shows that just before Ice Ages, the Artic regions have record peaks in their temperatures. It seemed that no-one was too sure about why this was the case but what seemed to be popular was how very high Artic temperatures affected the percentage of the ocean covered by ice and the different amounts of heat that land and water absorb (and also how the Southern Hemisphere was different because of its different ratio of land to water). This seemed to be pretty established physics at the time and no-one mentioned anything about global warming. Though the question of just exactly how this all worked was still up in the air. It just seems that people are applying what is known about past Ice Ages and theorising that if record high temperatures in the Artic Circle which preceded previous Ice Ages played a direct role in the Ice Ages (and you have to admit, it's pretty reasonable to assume this), global warming may eventually result in an Ice Age as well due to the same conditions that caused previous Ice Ages.
    • by RevMike (632002) <revMike.gmail@com> on Saturday April 17, 2004 @11:22AM (#8891834) Journal

      The Gulf of Mexico is a large tropical sea with very warm water. A major ocean current, called the Gulf Stream, carries warm water from the Gulf up the east coast of the United States, starts to curve to the east as it passes Virginia, makes a sharper turn east near Cape Cod, heads straight for Ireland and Britain, turns south and heads down the French coast to Spain. The heat from the Gulf Stream warms northwestern Europe, and is the reason why London is as far north as Quebec and Moscow, but doesn't get 4 meters of snow every winter.

      The mechanism that causes the Gulf Stream to flow is that cold water is denser than warm water. The arctic water up near Greenland and Iceland sinks and the warmer, less dense water from the Gulf of Mexico flows up to take its place.

      However, salinity also affects water density. If enough fresh water from the ice cap melts and flows into the area around Newfoundland-Greenland-Iceland-Scotland, the water won't be dense enough to sink. Therefore the warm water will stop flowing north from the Gulf of Mexico.

      Now London gets 4 meters of snow. Scandanavians laugh at them.

      Of course, this will also cause the ice cap to stop melting in this area, but it will take quite a long time to "prime the pump", perhaps several thousand years. In the meantime, the northeastern United States and Northwestern Europe experience an "Ice Age" where their climate more closely resembles the climate of Russia at similar lattitudes.

  • Good idea... (Score:3, Insightful)

    by Pedrito (94783) on Saturday April 17, 2004 @09:41AM (#8891313) Homepage
    For those of you who would rather do something before it's too late, iron seems to work, but the long-term ecological implications are still unknown.

    Yeah, there's a good idea. I read that article and while on the surface it seems like a grand idea, it's the second part of your statement that concerns me. We don't know the long-term ecological implications and frankly, I think we'd be more likely to do long-term damage than long-term good. I just don't trust our knowledge of global warming and cooling

    I think for now we're much better off sticking with reduction of greenhouse gas creation until we better understand our environment.

    Here's the problem. Scientists say, "we've got global warming," and hey, maybe we do, but the Earth also goes through cycles of warming and cooling that are natural, and we don't entirely understand these yet. So now scientists aren't sure if we've got global warming or if we're simply in a natural warming stage. Yes, we do have manmade greenhouse gases. There's no question, but how much this is actually affecting global warming is up for debate.

    There are many unknowns. And as we like to quote from the White House, some of those unknowns are known. Some of them are unknown. Until we really understand how global climate operates (maybe in 50 years, maybe longer), I don't think we should do anything to cause any intentional major changes because the damage we could wreak may be well beyond our ability to control, before it's too late.

    But that's just my opinion.
  • But! (Score:5, Funny)

    by schnitzi (243781) on Saturday April 17, 2004 @09:43AM (#8891328) Homepage
    But _The Day After Tomorrow_ is by the director [imdb.com] of Independence Day -- how could it be anything but a quality picture?
  • by emaveneau (552950) * on Saturday April 17, 2004 @10:49AM (#8891666)

    All iron seeding studies as of 2003 [bbm.me.uk], confirmed the consumption of CO2 but

    Other gases are produced (eg DMS), and other limiting nutrients (nitrates and phosphorous) are used up. ...

    What has *not* been found is any proof that any additional carbon sinks to the ocean floor and gets buried, thus entering long-term storage.

    Fast forward to 2004.

    There is an article in nature [nature.com], published on March 17 2004, whose abstract says iron is not a panacea

    Only a small proportion of the mixed-layer POC [particulate organic carbon] was intercepted by the traps. ... The depletion of silicic acid and the inefficient transfer of iron-increased POC below the permanent thermocline have major implications ... for proposed geo-engineering schemes to increase oceanic carbon sequestration.
    Audio interview, (8:36 ogg, 3.3Mb) [www.cbc.ca] with one of the authors. Source story [www.cbc.ca].

    Apparently the study linked to [calstate.edu] in the original post has two studies who's results will be published in April 2004

    ... in the same issue of Science ... [which] indicate
    that much of the carbon sank to hundreds of meters below the surface.

    So what do we know for sure? Adding iron does cause a bloom, and does drawdown CO2 but other nutrients are used up and the CO2's ultimate fate is debatable.

    The conflicting results could be regional variation in ocean conditions, but IANAO.

    Either way global warming is real, and the film may bring to light the severity of future changes.

  • This topic is amazingly timely for me as I'll be giving a presentation to a group of geophysicists on Tuesday about abrupt climate change in the last 100,000 years and the upcoming 10,000.

    When I first got into this business in the early 90s I spent a lot of time discussing these topics on sci.environment.

    It may be worth pointing out that climate change over the past decade has panned out pretty much as was expected ten years ago. It's interesting that this hasn't affected the cerdibility of the field very much.

    I've dabbled a bit in sci.environment again in the last few months, but it's been a lot less satisfying. Ten years ago I had the privilege of getting into flame wars with no less than John McCarthy, as well as many other less famous but comparably intelligent, very well-informed conservatively inclined people.

    To be sure, there were also many throughly propagandized folks, mostly aligned in two opposing camps, but it was possible to have a serious debate and even, once in a while, score a point.

    The conversation on Slashdot is only marginally better than the decaying thrashings on sci.environment. It's better because most people here are grinding different axes, and so their ill-informed commentary is less shrill and confrontational.

    There's a hell of a lot of misinformation going around here, though. It's pretty discouraging to see what gets moderated to 5, insightful or informative.

    Even the hacker community, chastened though it should be by the ways in which writing code makes you face your mistakes, is sadly overconfident about its opinions. People make broad and confident statements on matters where, (obviously to those few of us here who are serious students of the matter) they know very little. Moderators sharing the politics of the poster mod these up to "insightful" ore even worse "informative".

    Let me review the settled science. There's a lot that's unsettled, but when I see these points debated I despair for democracy:

    • Climate, defined as the long-term average behavior of the atmsophere, ocean and ice, shows a lot of natural variability in response to perturbations in forcing.
    • While the underlying principles of climate physics are not exotic, the number of degrees of freedom of the system makes the system behavior difficult to predict in detail
    • While details are difficult to predict, certain global constraints (mass, energy and angular momentum conservation) allows more confident predictions about the big picture than about the details.
    • Complex computer models are the only way to get any idea about the details, but the global picture can be discussed using old-fashioned paper-and-pencil models
    • Human behavior is altering the energetic balance of the atmosphere at a larger rate than is normal in nature, with very rare exceptions such as asteroid impacts.
    • The simple calculations indicate the short term response of the system to this perturbation will be warming at the surface, concentrated at high latitudes, and cooling in the stratosphere.
    • Observations and complex computer models agree with the first order predictions
    • Chaos doesn't enter into it in the way that many people suggest. Climate prediction is different than weather prediction. Weather prediction out beyond a month is probably impossible, and even if it turns out to be possible, two months isn't. Climate is the average properties of weather. When I say that Christmas in Chicago is going to be colder than the fourth of July in 2304, I am making a 300 year climate prediction, and a perfectly reasonable one.
    • The longer and more intense the perturbation, the larger the likelhood that our models (both computer models and simple conceptual models) will fail, due to lack of inclusion of normally slowly-changing phenomena taht are more likely to be in play with larger perturbations. In this case, the models will fail in the direction of understating, rather than overstating the consequences.
    • by andrel (85594) <andrel@yahoo.com> on Saturday April 17, 2004 @12:40PM (#8892302) Journal
      I agree with you that the public discourse about science (and medicine) is dominated by pepole who are appalingly naive and misinformed. Alas, mathematics educators are busy fighting about calculus reform instead of figuring out how to teach probability/statistics in high school.

      I have a question about the nature of climate. You say:

      Climate, defined as the long-term average behavior of the atmsophere, ocean and ice, shows a lot of natural variability in response to perturbations in forcing.

      What about 1/f noise? Are we studying a stationary random process? Is it even legitimate from a mathematical-modeling viewpoint to talk about long-term average behavior? The prediction you make about 2304 is reasonable, but hardly long-term by geological standards.
      • Is it even legitimate from a mathematical-modeling viewpoint to talk about long-term average behavior?

        Indeed, in a formal sense it is not easy to make a distinction between climate and weather. The casual statement "climate is the statistics of weather" becomes formally unsatisfactory when one starts to talk about climate change .

        Nevertheless, I hope you will admit that I am saying something both meaningful and true when I say that the climate of Kansas City Missouri is more variable than that of Portland Oregon. How to cast this into a formal mathematical statement is not obvious, but probably not relevant for the current discussion. Whether it ought to be a practical issue for the field is something I've wondered about, but I don't think it's a current topic.

        Interestingly, "climate" is conceptually better defined in our complex models than in the real world, because our models have finite sets of forcings and of free variables, and thus a clearer distinction between intrinsic and extrinsic variability than the real world does.

        The prediction you make about 2304 is reasonable, but hardly long-term by geological standards.

        Actually, the prediction is robust for any location at 40 degrees north latitude, at any date, on physical grounds, as long as the atmosphere is not almost totally opaque to incoming shortwave radiation (a.k.a. "sunshine") as on Venus.

        I simply use it to illustrate that the predictability horizon of weather (defined as preturbations about the climatological mean) does not amount to a predictability constraint on the climate itself. I will make the same assertion for 30,000 years in the future, if you assure me that "Chicago" will be meaningful that far into the future (which I very much hope will be the case!)

        I understand this doesn't go directly to your question, which is mathematical rather than physical. Climate is definitely not stationary, and quite possibly not even ergodic.

        Climate is easy to define formally in our models though, much more so than in the real world. Our models can do multiple realizations of a particular year, based on specific boundary conditions and forcings. We capture enough of the variability in these models that the realizations differ. We treat the variations among these realizations as stochastic weather and the commonalities as deterministic climate.

        In the real world, as opposed to in models, there is only one realization, and in fact, no clear distinction between intrinsic and extrinsic processes. So our meta-model, our model of the model, is difficult to justify formally.

        In practice we don't dwell on this much. We just treat the real world as a superposition of chaotic dynamic variability (an unpredictable part) and deterministic climate change which sets up the statistical properties of the chaos.

        In the simple chaotic dynamics view, weather is the state of the system (the wandering dot), and climate is the shape of the set of permissible trajectories (the whole phase diagram). Things aren't necessarily that simple in fact, but we don't have a better way of addressing the issue. Ultimately, we aren't trying to prove theorems, we're trying to elucidate complex physics, and this view appears to be both necessary and sufficient for most of our purposes.

  • by pfdietz (33112) on Saturday April 17, 2004 @11:48AM (#8892003)
    There's an unfortunate side effect of fertilizing the ocean with iron: the increased microbial activity will cause more N2O (nitrous oxide) to be released from the oceans. N2O is a much more effective greenhouse gas than CO2, and it stays in the atmosphere for centuries.
  • Goodbye Science (Score:3, Insightful)

    by Henry V .009 (518000) on Saturday April 17, 2004 @11:49AM (#8892005) Journal
    What this prediction does is to make Global Warming completely unfalsifiable. If things get a little warmer, it proves that Global Warming is imminent. If things get a little colder, it's because Global Warming is imminent. If things stay the same (which they generally never do) then that just proves that we are at an unstable tipping point. Goodbye science, hello politics.
  • I think it will be many years before anything worthwhile comes from the IPCC and their models. I you check out chapter 7 you will find they advise why they have not included water vapour in the atmosphere in their modeles.

    The issue is that water vapour is by FAR the most important greenhouse gas. CO2 is about 365 ppm these days - or 0.0356% while water vapour is in the range of 2-4% and this makes water vapour 100 TIMES more important.

    Next, we need to consider irrigation. The CIA factbook does have land under irrigation on a country by country basis. It is clear these irrigation projects collectively are very significant and they have the effect of turning vast areas of arid land into moist land. All that water ends up transpired or evaporated into the atmosphere.

    If we consider fossil fuels we find another large source of water vapour.

    If we add it all together, which the IPCC has not done, what we find is that there has been a change in the amount of water vaopur released into the atmosphere from mankind's activites and then we must note that the UNCERTANTY in the measuremens of the water vapour are much greater than the total amount of trace gases.

    Water vapour is 2 orders of magnitude more significant in concentration and it is a stronger absorber of Ultraviolet light in ALL wavelengths.

    ---------------

    That being said, our climatologist look at an extremely short time frame. The earth has been around for about 4.5 billion years. By 570 million years ago, it had warmed and then it stayed warm for close to 90% of the time since then. There really only were 4 cold snaps and we have been in one for the last two million years. And during this last 2 million years it appears we have enjoyed about 20 ice ages, the last of which ended only 18,000 years ago.

    To contrast the duration of time, suppose we were to stack up the volumes of the encyclopeadia Brittanica. If we count the number of pages we might find the thickness of each page would correspond to say about 100,000 years of the earths history.

    This means that our climate modelers basically collect there data from usually less than 1/1000th of the thickness of the last page and meanwhile they ignore everything else.

    IMHO this does not bode very well for their ability to make valid predictions.
  • CO2 Concentrations (Score:3, Insightful)

    by foxalopex (522681) on Saturday April 17, 2004 @11:09PM (#8895461)
    I remember reading a National Geographic article nothing that CO2 concentrations have been their highest in 400,000 years thanks to ice core samples in the arctic. This was through several ice ages and the most recent dramatic spike being the start of our industrial age. Whether or not this causes global warming or climate change or it's outcome no one is really sure of. However considering earth is our life support, can you risk messing around with it? I think it's something to be concerned about rather than completely ignoring. The solution however is a difficult one. Knowing how we do things thou, we'll likely do something when it's too late sadly.

"Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats." -- Howard Aiken

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