World's Ice Caps are Melting!

Discussion in 'Earth Science' started by duendy, Sep 28, 2005.

  1. MetaKron Registered Senior Member

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    5,502
    It is obviously much more important to keep marijuana cigarettes out of the hands of our children than it is to reverse global warming. Everyone tell the DEA to keep up the good work.
     
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  3. Gudgeon Registered Member

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    Yes, and revert to hybird cars ASAP to reduce the amount of emmissions
     
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  5. valich Registered Senior Member

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    Acording to computerized scenarios and evidence in geological rock formations the Earth's magnetic poles reverse about every 40,000 years. The magnetic fields of the Noth and South Poles are generated from the continuous movement of the Earth's iron core within the center of the Earth. Sometimes this reversal occurs relatively fast but other times it has been documented to take place at a rate of about 6 degrees in 16 million years. I'm not sure at how they arrived at this figure, but it is a fact that the Earth reverses it's magnetic poles and this is scientifically documented through the analysis of the orientation of historical records of rock formations.
     
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  7. Avatar smoking revolver Valued Senior Member

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    As I remember (which may be not 100% correct) every rock when created then also gets its' magnetical aligment, i.e., its' tiny magnetic field is set to where magnetic N and S is. So, if analysing old rocks from different periods of time we can see where the N and S magnetic poles were at the moment the rocks were created.
     
  8. valich Registered Senior Member

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    3,501
    That's exactly correct! This is one way, aside from carbon isotope dating, that geologists use to date rocks and geological formations. Right on bud!
     
  9. SkinWalker Archaeology / Anthropology Moderator

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    You are keeping in mind that the last geomagnetic reversal was at about 780,000 years ago and that there is no apparent periodicity to the events in the geologic record. Some are a few thousand years apart; some a few million; some are tens of thousands; still others separated by hundreds of thousands of years.

    The evidence for these reversals is found best in the sea-floor spreading outward from the mid-oceanic rifts where the curie points of the rocks have oriented the molecules of magnetically affected minerals such as magnetite so as to orient themselves in the direction of the north pole of a give point in time.
     
  10. valich Registered Senior Member

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    3,501
    The Antarctic is a "land" continent, while the Arctic is composed of total ice. You cannot say that we are now seeing two island continents being formed in the Antarctic. There is a massive slab of ice sheet(s) and icebergs seperating away from the outer edges of that Antarctic land continent that are drifting North and will melt to increase the overall sea level.

    In the Arctic, it is predicted that in about fifty years, the summers in the Arctic will be totally ice-free. This is good news for shipping-freight transportation, but terrible news for rises in ocean waters. Both the Arctic and Antarctic will become smaller ice caps. Polar bears, seals, and other Arctic wildlife will diminish. Already scientists are seeing a decrease in the permafrost level (lowering of the permanent underground ice level) in the upper regions of Alaska and Canada that is causing large destructions of forest regions because of the decrease in water that is available for their growth.

    The Native American Inuit Indians in Northeast Canada (Labrador) and other Northern regions are filing lawsuites with the government because they can no longer obtain their subsistence food by fishing in the surrounding areas because they can no longer walk out onto the former ice sheets and cut through these ice sheets to fish, because the ice sheets are now too thin to walk on. They are unable to go out in the winters to obtain food (fish) that they depend on for survival because the ice is now to thin to walk on safely without falling through.

    The glaciers of Greenland are now receeding at a rate of over 100 ft. per year, compared to just 5-10 feet a few years ago. Even in the United States, talk to anyone who works at or knows much about Glacier National Park in Montana at the Canadian border and they will tell you that the glaciers that were there fifty years ago no longer exist.

    Isostatic forces refer to the force of gravity that tends to balance the height and depression of landmasses. This has nothing to do with the permanent human-induced climatic changes that we are seeing today: global warming through the covering of our atmosphere with pollutants and the excessive deadly, cancer-producing ultraviolet rays now coming in because of the destruction of our ozone layer by the realease of man-made manufactured chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons released in aerosal cans. Every year, in the last five years or so, since we've been monitoring it, we have been seeing a larger and larger hole in the ozone layer that is continously growing between the Antarctic and South America. The reason that we are seeing it there, and not directly over the most polluting countries on Earth, like the United States, is because of wind convection, the rotation of the Earth, vortex forces, etc. I'm not sure exactly why but a meteorologist could certainly supply a more detailed explanation.

    Either way, we are destroying our environment at a "rate" that has never before seen in the history of the Earth. The Earth has gone through similar cycles, some of which have resulted in mass extinctions, but we have never been able to document such a detrimental change as we are seeing right now.
     
  11. valich Registered Senior Member

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    Does your source suggest any periodicity in the reversals? I'm afraid that the geological book that I quickly looked this up in might be too outdated. It stated a reversal 40,000 years ago and another gradual change of 6 degrees per year over about a 150,000 year period. It would be beneficial to us all if you could post exactly what your source states as I'm sure that the factual information has progressed tremendously since what is stated in my apparently outdated source. Thanks!
     
  12. Xylene Valued Senior Member

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    1,398
    It depends who you listen to, may_wentee. If the conservative scientists are right, you're looking at a metre or so of sea-level rise by 2100. (Which would be bad enough). If you listen to the people who talk about the possibility of methan clathrate deposits being released from the ocean floor--well, if they're right there'll be about 80-90 metres of sea-level rise by 2100 AD, which would be rather drastic

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    to put it politely. I tend to think the second group are a bit more on the mark. At the very least, I'd say we'd be looking at the Greenland Icesheet going this century, (which would add 6.5-7 meters to sea-level) but I'm not sure how much of Antarctica will go. Hopefully not all by 2100, but plan for it anyway just in case (God forbid).
     
  13. valich Registered Senior Member

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    The estimates are underestimated to pacify the masses. Does anyone know if land is for sale on Mt. Everest? Just thought I'd add in a little humor, but there are large sections of the U.S. that are going to be underwater unless our government builds dikes. Look what just happened to New Orleans and it even had levees in place - yes I know this is unrelated. But the Outer Islands of North Carolina will be gone along with most of the Chesapeake Bay area around Norfolk - only a few inches above sea level - just to name a few!
     
  14. Xylene Valued Senior Member

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    300 feet of sea level rise will put most of the Eastern US underwater, valich.
     
  15. valich Registered Senior Member

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    That's an over estimate though. 300 feet will touch some of the Appalachian mountains. Need not be nearly that high to put most of the continent in jeopardy. A few inches will cause major havoc.
     
  16. Anomalous Banned Banned

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    1,710
    Remember the movie, Water World

    most people had thought that movie was proposterous but look at us today

    we should learn from that movie, I mean to live on water and use sea, because human greed will definately doom us.
     
  17. Avatar smoking revolver Valued Senior Member

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    19,083
    There is not so much water in the world to make Water World happen,
    a 80-100m increase is the absolute maximum.
     
  18. EmptyForceOfChi Banned Banned

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    i agree with avatar there isnt enough water to make it like water world there will still be high land marks hilly areas and mountinous peaks above water level, but something simular to water world will happen possibly, our main transportation would be boat type crafts, possibly flying crafts, but what will we do for recourse gathering when our land is under water levels. it will be alot harder to function as a society, i predict wars, and fighting like water world and chaos, but not so much water, be fun if a meteor impacted with earth when the water levels are so high, (fun to see but not live throgh ofcourse)
     
  19. valich Registered Senior Member

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    I never saw the movie, but we are feeling the effects of the oceans rising and the ice caps melting right now! Read my post above. There's already an overpopulation problem on earth: this will only cause it to be worse. I think that the world is already too overcrowded. Where do we go to not feel overcrowded: to have more individual freedom and relief? To feel calm and in harmony with Nature? To relieve our everyday stress? To find our individual space or to be alone? Hundreds of miles of glaciers are melting and the surrounding pristine forsts are dying because of the thermofrost layer melting.
     
  20. Anomalous Banned Banned

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    1,710
    Thats a very important point, I never thought about that before. Infact we are so dumb, we never think about these things, I think now its too late
     
  21. valich Registered Senior Member

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    The solid Earth's core consited mostly of iron with a surrounding fluid core that circulates in patterns around it. This is what produces the Earth's magnetic field.

    The North and South poles deviate by a few degrees every million years or so. The last reversal occurred about 780 million years ago but the "average" reversal occurrs about every 250-300 million years: geographic history is like a grain of sand to us.
    See: http://en.wikipedia.org/wiki/Geomagnetic_reversal
     
  22. Facial Valued Senior Member

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    Where's Edufer? I would like to see him deny this and brand this a conspiracy.
     
  23. valich Registered Senior Member

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    You are referring to human transient time periods though. The average reversals throughout the Earth's time period is 250,000 years, and this is substantiated especially through measuring the North-South orientation of rocks spread out over time from the Atlantic Mid-Ocean Ridge.
     

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