The next coming of the Ice Age?

Discussion in 'Earth Science' started by The Singularity, Apr 15, 2004.

  1. The Singularity The last thing you'll ever see Registered Senior Member

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    Now I don't know if this was already mentioned in another thread ... but I don't want to look over several years worth of threads to catch up (seeing that I am new) so I'll start a new one on this.

    From what I know about global climate and atmospheric/oceanic dynamics, I feel as though that all this global warming will lead to the next Ice Age and it may happen sooner then what everyone may think. Let me explain.

    First, there has been records from Earth's past that CO2 levels in the atmosphere has been as high as it is today before dropping back down to "normal" levels. Even before the industrial revolution, there has been several long periods of time where the CO2 level has risen like it is today before the Earth activated some kind of mechanism to bring back those CO2 emissions down to respectable levels, like a safety mechanism. As it is seen today, CO2 emissions are continuing to rise ... in fact, it has risen beyond past levels before the planet brought them back down. This could mean that the planet either has not yet activated its mechanism to bring down these CO2 emissions or it has completely stopped the cycle. This in turn would continuously raise global temperatures so the whole problem of us being the main cause for global warming may have been blown all out of proportion because of it. We may be speeding it up but I don't think we are the main reason why the planet is warming up.

    With this global warming, the polar ice caps would melt and dump millions of litres of fresh water into the ocean. Since fresh water is more dense then the salt water of the ocean, the fresh water would sink to the bottom and disrupt ocean circulations. As in the case of the Eastern seaboard of North America, we get our warm air from the Gulf stream. And if the fresh water from the northern pole sinks to the bottom, it would interfere with local ocean circulations, most probably affect the Gulf stream, and forcing the Gulf stream to deflect further East instead of its current Northern path. Or it may even stop moving warm water and air northward. This would entail a cut-off of the warm air we get from the south and cause a chain reaction which would lead to the next Ice Age.

    Now this is all subject to disagreement but then again, everything in science is rarely seen on the same level for everyone. So I would like to know what you people think of this.
     
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  3. Pete It's not rocket surgery Registered Senior Member

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    Welcome to the forums.
    Yep, could happen. I think climate change models are still in their infancy, so I hesitate to place any degree of confidence in any long-term predictions just yet.
    I don't think it really makes a hell of a difference - in the long long term, it's just temporary stuff anyway (ie global warming and ice ages will happen sooner or later regardless of humanity's influence).
     
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  5. Starthane Xyzth returns occasionally... Valued Senior Member

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  7. Edufer Tired warrior Registered Senior Member

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    Welcome to the forum, Singularity. You have landed right in the middle of the Snake Pit. Don’t worry, a few bites will immunize you quite soon.

    Beware. At the age 20 you are fresh meat for catastrophism – don’t let them fool and scare you.

    You seem to believe that present CO2 levels are “normal”, and any other concentrations are bad, and nature takes corrective actions to return to normal levels. This belief is called “animism”, where Nature is invested with human traits. See in this webpage what is meant by “animism in science” : http://www.ems.psu.edu/~fraser/Bad/PatheticFallacy.html

    This is part of a nice educational website “Bad Science”, by Alastair B. Fraser, a professor of Physics, that will give you a lot of good, sound information about atmospheric sciences : http://www.ems.psu.edu/~fraser/BadScience.html

    Well, the fact is nature couldn’t care less for what happens on Earth and everything on its face. In that fashion, CO2 levels have been varying wildly along Earth history, and you’d be surprised to know that during the Cretaceous period (150-65 million years ago) CO2 levels decreased from 6000 parts per million (ppm) down to 2600 ppm – but curiously enough, temperatures during the Cretaceous were barely 2º C higher than now. Paleoclimatology has given us all that data. So don’t worry if CO2 levels double in the future up to 740 ppm. There would be only about a 0.25º C increase.

    Then there comes the established fact that CO2 concentrations lag temperature increase by some 800 to 1200 years, meaning that temperature increase is what provokes CO2 increase and not the reverse. Scientific proofs? Monnin et al., in their paper in Science, Vol 291, Issue 5501, 112-114, 5 January 2001 “Atmospheric CO2 Concentrations over the Last Glacial Termination” determined that CO2 levels began to rise on Earth 800 years after temperatures rose. They made their study in Antarctica, and until now, nobody has challenged their discovery – although it disassembles Global Warming hypothesis that CO2 rise will lead to a catastrophic global warming. As this study passed unnoticed by the “mainstream” media, IPCC and followers preferred to keep it silent, under the rug, and not stir the waters.

    The favorite scenario of certain climate modelers is one in which the North Atlantic oceanic “conveyor belt” and Gulf Stream are turned off, thereby turning Western Europe into Siberia. But more realistic models show that the warmer European temperatures are not set by the Gulf Stream but by the perturbation of the atmospheric circulation induced by the Rocky Mountains of the Western US [Seager, Richard. 2003. Quart. J Royal Meterorol. Soc]. Another model shows that even as there is a freshening of the North Atlantic, the conveyor belt is strengthened not weakened: Read the abstract:

    http://www.agu.org/pubs/crossref/2004/2003GL018584.shtml
    <dir>GEOPHYSICAL RESEARCH LETTERS, VOL. 31, L02301, doi:10.1029/2003GL018584, 2004

    Does the recent freshening trend in the North Atlantic indicate a weakening thermohaline circulation?

    Peili Wu, Richard Wood, and Peter Stott
    Met Office, Hadley Centre for Climate Prediction and Research, United Kingdom

    Abstract
    [1] It is widely expected that the thermohaline circulation of the ocean will slow down as greenhouse gas concentration in the atmosphere increases. This is partly due to an intensified hydrological cycle in a warmer climate. Is the recent observed freshening trend in the North Atlantic an indication of what has been expected? We report a similar freshening trend reproduced in an ensemble of four coupled model simulations with all major historical external (natural and anthropogenic) forcings. The modeled freshening trend originates from the Arctic Ocean where sea ice decrease and river runoffs increase with the same trend. Instead of weakening, we find an upward trend in the North Atlantic meridional overturning circulation.
    Received 9 September 2003; accepted 3 December 2003; published 20 January 2004.</dir>
    Finally, we have the direct evidence from the atmosphere: Previous warmings, the Holocene optimum (8000-5000 BP) and the Medieval Climate Optimum (ca. 1000 AD), did not cause any abrupt cooling.

    Global cooling is coming for sure, but no because any warming (would you make ice for your whiskey in the oven?) but because there is a Double Gleissberg minimum coming by 2030, and that will take Earth back to a climate similar to the Little ice Age of the 1450-1700s.

    See details of this in: Solar Wind near Earth: Indication of Variations in Global Temperature, by Dr. Theodor Landscheidt. http://mitosyfraudes.8k.com/Calen/SolarWind.html

    You are young enough to be living at that time. So I would advise you to find a job in any tropical country, before they get crowded. And remeber to take along you surfboard (or your snowboard, in Canada) and enjoy life. Nothing is going to change abruptly. It will take some couple of thousands years to really go into the next glaciation. As you now, the present Holocene has been going for 10,500 years so we are 500 past the limit.
     
  8. Starthane Xyzth returns occasionally... Valued Senior Member

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    Didn't some of the previous interglacials last 20 or 30 thousand years? I doubt that the global climatic system is simple or clockwork enough to make it a regular, even pattern, even if long-term astronomical variations (Milankovich Cycles, etc) do have some causitive effect on Ice Ages.
     
  9. The Singularity The last thing you'll ever see Registered Senior Member

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    Just to make sure there isn't any confusion about my stance ... I'm not worried about the next global glaciation happening within my lifetime. I'll admit, I would like to see it happen to see how humanity and all life on Earth would adjust but i am thinking realistically. What's happening now may or may not cause the next major glaciation but to me, I think of it as a very possible outcome from all this global warming in the future.

    I should say I'm really into natural disasters ... such as hurricanes, tornadoes, earthquakes, and such ... that's probably why I'm interested in the Earth sciences in the first place.

    Of course, there's probably a better chance of an asteroid ("global killer") hitting the Earth then the next major ice age happening within the next half millenia or so. But anything is possible and probably the only thing missing along with everything thats happening now is a trigger to cause a glaciation. And as we've seen countless number of times, the atmosphere and climate can change very rapidly in a given area without reason.
     
  10. Mr. Chips Banned Banned

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    954
    Starthane, the cycle has been amazingly regular for the past million years or so, about 100,000 years for ice age conditions followed or preceded by 15,000 years of interglacial. Clockwork, as for a pendulum? That is exactly how it appears to be, like a damped sine wave. Slow long ice age conditions breaking to shorter interglacials to less long ice ages to ever shorter interglacials until we have gotten to this point of having seen little similar oscillations, like those little vibrations as the pendulum approaches equilibrium. You can begin to see it in the graphs here http://www.clearlight.com/~mhieb/WVFossils/ice_ages.html Realize that the earth appears to have been in ice age conditions about 90% of the time.

    This might just become of importance to you in this lifetime. Check out http://www.iceagenow.com/ or the books offered at http://www.remineralize.org/

    Using ocean sediments to determine ice age cycles as well as the concentration of atmospheric gases present during the oscillations is considered to be fairly error prone. How much it may be off was suggested by research designed to avoid the error, direct reading of oxygen ratios in long undistrbed water spring crystal formations. The conclusion was that the ocean sediment time scale was off by ten thousand years, an incredible amount of error. What has made it more diffictult for people to acknowledge these experiments is that it suggests that carbon dioxide concentrations peaked right at the beginning of ice ages rather than at the end. Get it, green house gas increase may trigger the start of ice ages.
     
  11. Starthane Xyzth returns occasionally... Valued Senior Member

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    Thankyou for the links, Mr.Chips... however, I think that iceagenow.com site is just a little on the side of pseudo-scientific sensationalism:

    >>"The next ice age could begin any day.
    Next week, next month, next year, it's not a question of if, only when. One day you'll wake up -- or you won't wake up, rather -- buried beneath nine stories of snow. It's all part of a dependable, predictable cycle, a natural cycle that returns like clockwork every 11,500 years"

    It can hardly be anything like THAT abrupt! There would be a few years of steadily worsening winters, until a year comes when winter simply fails to end. The snow would remain throughout the year in enough places to begin building up large-scale glaciers, as the next winter's snow adds to it. Nine stories would take a decade at least.

    The author's figure of 11,500 years for each interglacial doesn't quite agree with your 15,000 - the truth is, no-one has any certain figure.

    Bear in mind that, for much of the "ice age" periods, the climate in Europe and most of North America was simply a lot colder than today - not Arctic. There would have been a fairly biodiverse periglacial steppe, boreal forest and generally Siberian-type conditions where now we have the temperate zone. The actual ice sheets only reached their greatest extent for about 10 - 20 millennia, with at least one milder interstadial in the middle of the last glacial period.

    As for greenhouse gas buildup precipitating glaciation: I quite agree, and have mentioned it in another thread. Biomass in the oceans would exponentiate due to the CO2 concentration, resulting in too much photosynthesis and subsequent rapid draw-down of the CO2. At least the World's fishing industies would have a few boom years!
     
  12. Mr. Chips Banned Banned

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    Yes. I quite agree about the iceagenow site. I do go there regularly and check out his listing of snowfall, rainfall and temperature record breakings which I would prefer also included higher heat events but he does have a book to sell. I believe the Hamaker hypothesis is much greater merit science with some extensive real-time experimental evidence in the manner of soil remineralization to back up its major hypothesis.

    I see the different lengths of interglacials to be reported at between 10,000 to 15,000 years and expect the difference might be in the baselines used to determine the conditions.

    As far as Ice age conditions coming on abruptly, researchers of the deep ice core samples have said that anywhere from a decade or two appears to have been the case. You can see the claim of abrupt change made at this site if you scroll down to the fourth subject: http://www.pbs.org/wgbh/nova/warnings/stories/nojs.html It is only a brief summary of the findings. Look around some and I think you will see that the evidence does point out abrupt change to ice age conditions happened. Pollen deposit samples that suggested the same thing is part of what got Hamaker to formulate his opinion. Ice core samples don't go back very far though, at the most, two cycles. Deep sea sediment analysis, though perhaps off greatly as far as concentration of atmospheric gases goes, still shows the pattern in the ice cores and going back further. Same for the cave wall crystal analysis.

    In all of the cogent graphs of the cycles, see that it is basically of a ramp wave? According to these graphs, the cooling happens fast, the planet snaps into it's regular state of being and then gradually works its way up into the rather precarious conditions of relative warmth, the interglacials.
     
  13. kmguru Staff Member

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    11,757
    Hi Singularity:

    Welcome to Sciforums. Anytime you discuss about the universe, always remember any variable has differing amplitudes over time domain. It is like a multiple sine waves each with their own time cycle. Most of the time, we humans think everything runs in a steady state and hence if something changes, it must be the humans that are the cause - because, we think, we are the only powerful variable in the universe.
     
  14. Starthane Xyzth returns occasionally... Valued Senior Member

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    I don't think "normal" is the word for glacial periods: most of the Earth's history has been completely free of glaciers, warmer than we are today. It's only since the Miocene Epoch that permanent icecaps have existed at either pole; for most of the last 2 million years, yes, they have been more extensive than at present.

    Prior to the first Miocene glaciers forming, there is no geological evidence of ice ages since the Carboniferous Period, about 300 million years ago.
     
  15. Mr. Chips Banned Banned

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    954
    I looked aroung on the web and this site has a graph purported to represent the last 2.3 billion years. It is not depicted well but I figure the interglacials are the peaks to the right and the glacial periods are the troughs to the left. http://www.globalchange.umich.edu/globalchange1/current/lectures/samson/climate_patterns/

    Much error must be assumed to be included in such as our ability to surmise what happened way back when must be open to debate. The first graph I saw attempting to depict the cycles during all of earth's time was presented by Sir Frederich Hoyle in his book "Ice, The Ultimate Human Catastrophe" 1981. The last snowball earth episode is considered as ending about 600 million years ago (suggested to have ended due to the volcanic release of carbon dioxide just as you note)..

    If you just use the common graphs of 400,000 years, you can see a regular cycle, ice ages lasting 100,000 years with interglacials of about 10,000. 10 out of 110 suggests 91 percent for that time period. Hoyle's graph showed the first cycles as long and slow but also depicted close to 90 % ice age conditions, including the earlier snowball earth episodes.
     
  16. Zarkov Banned Banned

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    Interesting to see "current opinion"....... but nobody has any real idea about any of it.

    All past data is irrevelant, because man has changed the rules.

    It is very interesting to see it all unfold... and I may add, it is not going to be a sloooooow process.... mean time ... party on in old logic.

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  17. eburacum45 Valued Senior Member

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    There is no way on this Earth that global warming will cause an ice age; that is too silly for words. Alterations in ocean currents might cause cooler winters in some parts of the world, but the increase in global temperatures elsewhere will mean that effect is short lived and local.
    The long term trend in the carbon cycle is for an increase in the amount of carbon absorbed into the crust, and a decrease in atmospheric carbon dioxide; this is one of the main reasons why we have been having ice ages for the last million years or so.

    Our planet is likely to get much cooler over the next ten million years or so; then it will get warmer again as the Sun increases slowly in brightness.

    Anthropogenic global warming and artificial climate forcing may be able to keep our planet at a comfortable temperature; but it might be uncomfortable for a while as we find out how the global climate really works.
    ------------
    SF worldbuilding at
    http://www.orionsarm.com
     
  18. Mr. Chips Banned Banned

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    eburacum45, I thought maybe the URL at the bottom of your last post contained references to back up your statements. Alas, appears to just be your sig.

    If you could provide some real data I would be appreciative. If you could convince me as to why the past records from ice cores and sediment samples showing rapid cooling is not possible now or the evidence that atmospheric concentrations of greenhouse gases couldn't lead to such, I would stand relieved.

    Thanks
     
  19. eburacum45 Valued Senior Member

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    1,297
    Don't misunderstand me, I do believe in rapid climate change; both the onset of an ice age and the melting of the ice at the end of a glacial period are very rapid, and lead to adjustments in sea level and alterations in the coastline which are extremely dramatic in a very short time.

    We expect a sea-level rise due to global warming of around a metre, no more than two over the next century; during the onset and ending of a glacial period the sea-level rises or falls ten metres or there abouts in a hundred years. Humanity has built millions of houses and has trillions of dollars of wealth tied up in the coastal lands, so we are less able to adapt to these sealevel changes than our palaeolithic ancestors.

    But don't look for a full fledged ice age brought on by global warming; it has been suggested that the cool spell around 8200 b.p. was caused by an increase in CO2 levels, melting the glaciers and reversing the Atlantic ocean currents; but this was a local phenomenon, with a reduction in temperatures in Europe and America of 5 degrees or so, not a full fledged ice age. The overall averaged temperature of the globe probably increased at that time.

    In this article in the New scientist,
    http://www.newscientist.com/news/news.jsp?id=ns99994888
    both Andrew Weaver of the University of Victoria in British Columbia, Canada and the chappie who first drew attention to the importance of ocean current reversal,Wallace Broecker himself, say that the scenario depicted in the film 'The day after Tomorrow' is extremely unlikely.
    In fact it may be damaging to a proper public understanding of the effects of anthopogenic warming.

    I am sure that our Earth will rapidly plunge into an ice age at some future date, as the long term levels of carbon dioxide are decreasing just as they did before the Carboniferous and Varangian ice ages. By artificial climate forcing, perhaps using CO2, water vapour or even more powerful exotic chemicals I believe it will be possible to postpone or prevent any new ice age until the gradually warming Sun is powerful enough to make them impossible.

    After that time, ten or twenty million years from now perhaps, we will have to start thinking about cooling off again...

    terraforming the Earth for the forseeable future.
     
  20. Mr. Chips Banned Banned

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    954
    Cool, thanks for the data. I need to look into past records of atmospheric gas concentrations. I did a report for a college class on this subject a few years ago and somewhere I have the data from the oxygen isotope ratios analysis done with cave wall crystals that I especially want to find. I understand there have been more such studies since my college report of about 1995. Hard for me to figure it out without my old report but somehow I related a possiblity that atmospheric concentrations of gases may be off significantly in most of the studies from either ice cores and/or ocean sediments. I drew up the graphs myself overlaid upon each other. I should have it somewhere. A filing cabinent diving I will go.

    In the mean time, if you come across any web reports of that cave wall isotope ratio use to determine past cycle, I'd love to hear of them.
     
  21. geistkiesel Valued Senior Member

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    pete, can you supply some data to support your conclusions regarding coming ice ages? Isn't climate a crucial parameter in the existence of any ice age? Paradox: A lot of ice requires a lot of ocean evaporation and attendant temperature vs. ice making temperature?

    Are you aware of any opposition to the general ice age theory? Like the challenge that an ice age as we understand the description ever happened?
    (See Cataclysm" Adair et al).

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