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Global Warming and the Precautionary Principle

  1. Nov 8, 2006 #1

    Andrew Mason

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    Let's suppose that, as many of the posters here believe, there is a good possibility that global warming is not priimarily caused or even signficantly contributed to by human CO2 emissions. Let's suppose that there is a very good possibility also that CO2 concentrations are not signficantly higher than they were a 100 years ago.

    What seems to me to be incontestible is that fossil carbon is being brought into the biosphere by humans. It is also incontestible that much of this carbon was deposited by plants that grew in an atmosphere much richer in CO2 and much less rich in O2.

    Given the consequences for life on earth of global warming, is it not reasonable to be cautious and limit CO2 emissions as much as possible even if there is a good chance it is not occurring?

    I don't pass going up hills. It is not because I am sure there is something coming. There seldom is. I exercise reasonable precaution because I don't really know.

    AM
     
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  3. Nov 8, 2006 #2

    Bystander

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    The history of atmospheric composition is contestible.

    The "consequences" aren't "given." Dire consequences have been postulated, based on "Rube Goldberg" concatenations of "if" statements.

    You are certain that the opposite lane is reserved for oncoming traffic, and that there is oncoming traffic. It is likewise certain that atmospheric CO2 levels are not driven by climate models, but by physical principles.
     
  4. Nov 8, 2006 #3

    Andrew Mason

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    So where, in your theory, did the carbon come from to make the coal, oil and gas, limestone, etc. that is in the earth?

    It depends on how much global warming we get. Are you suggesting that an increase of 10 degrees C is not serious? The point I am making is not that the consequences are certain, but that the possible consequences will have a serious negative impact on the earth - and we only have one planet that is fit for life.


    The point is that I am not certain there is oncoming traffic. Even on a lonely country road, I stick to my lane going up a hill.

    The problem here is that it is very complicated If scientists cannot agree on the result of increased CO2 in the atmosphere, it does not seem reasonable to pick the best case scenario.

    AM
     
    Last edited: Nov 9, 2006
  5. Nov 9, 2006 #4

    Bystander

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    "My theory?" You assert incontestible knowledge of the history of carbon dioxide and oxygen concentrations in the atmosphere, and I point out to you that it is contestible, and now "I've got a theory?" Are you referring to your "Sequestration" thread? In which case, it's not where the carbon came from, but where the oxygen came from and where all the carbon went.

    It's also possible that the pink elephants from Pluto will be landing tomorrow to kick us off the planet. Once a half dozen half-baked models have been strung together, the predictions aren't worth worrying about.

    The point is that you are ABSOLUTELY certain there is oncoming traffic, and that you have absolutely no idea where it is. The analogy between passing on hills and climate is lousy. You know climate changes. You also know that you haven't a clue what drives those changes in what directions.

    All science is done on "worst case" assumptions: there are always mistakes in the observations, data reduction, and interpretation of results. As a consequence, one does NOT leap to conclusions about z-rays, Piltdown man, polywater, space charge in electrolytes, cold fusion, or any number of other much ballyhooed results. One reviews theory, methods, results, interpretations, and conclusions.
     
  6. Nov 9, 2006 #5

    Andrew Mason

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    I merely observed that there was a lot of carbon in the earth that was once living at or near the surface of the earth. I was not aware there was some other explanation for it other than high levels of CO2 in the atmosphere. If you are saying that is contestible, I would like to hear another explanation.


    The predictions are based on a rational analysis of, albeit incomplete, data. But that does not mean they are wrong. We don't need proof beyond a reasonable doubt here. Not every earthquake leads to a tsunami, but after an earthquake I am not going to head for the beach.

    There may not be another car on the road at all. I don't know if there is traffic. I am not going to take the chance.

    But you are leaping to conclusions: that there is no danger that we ought to be cautious about.

    AM
     
    Last edited: Nov 9, 2006
  7. Nov 9, 2006 #6

    Bystander

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    The origins and evolution of the earth's atmosphere are wide open for speculation. Hit the textbooks and journals --- stay away from TLC, Disc. and Hist. Ch..

    Every earthquake does lead to a tsunami. That's physics. Not every earthquake is well enough coupled to the oceans to produce a large tsunami. That's why the networks of tsunami monitoring instruments have been established in various places around the world --- to cover the gap between theory and practice. The geophysicists know their theoretical foundations and models are garbage, and have taken the appropriate measures.

    You constructed a lousy analogy --- give it up. You KNOW there are other vehicles on the road. You know you are not in control of them. You know you have no clue where they are.

    No, I am not leaping to any such conclusion. There is NOT sufficient data to reach any conclusion. If you wish to take precautions against every monster in the closet, pink elephant from Pluto, angry god, collapsible dam, fallible levee, possible tire failure, potential lightning strike, tornado, meteor, mudslide, pyroclastic flow, sinkhole collapse, locust plague, and whatever else you choose to fret about, do so. Don't expect the world to follow suit.
     
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