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#11
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| On Tue, 9 Aug 2005 17:48:54 +0200, "Josef Matz" <[Only registered users see links. ]> wrote: I'm glad you opened on this subject. I've heard it stated many times before, but I still don't understand how floating ice can change the sea level when it melts. Except for the difference in density of the saline ocean water and the nearly salt free ice water, the ice should displace the same amount of water before as it will after melting. Put an ice cube in a beaker and note the water level. Let the ice cube melt and the water level should remain essentially the same. Gordon |
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#12
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| On Tue, 9 Aug 2005 05:54:29 -0400, "tadchem" <[Only registered users see links. ]> wrote: Ah! Now there is the big question. I contend that humans have contributed very little, or perhaps nothing significant toward any deviation from these established cycles. Solar energy output variations, earth axis inclination angle changes, meteorite impact and volcanic atmospheric pollution are the only events that I can identify that could have a significant effect on the earth's climate. Vesuvius probably blew more greenhouse gasses into the upper atmosphere than all of humanity's industrial age contributions. |
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#13
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| "Gordon" <[Only registered users see links. ]> schrieb im Newsbeitrag news:[Only registered users see links. ]... by can Shelf ice is no floating ice. It is very thick ice also. But warm sea water can force the melting process. The ocean there is very flat. Thats a difference to the north pole where the ice swims in water. Shelf ice goes to the ground which is beyond sea level. Joe |
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#14
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| "Gordon" <gordonlr@DELETEswbell.net> schrieb im Newsbeitrag news ice Definitively not ! The CO2 increase of the atmosphere clearly corresponds to the usage of fossile energies mainly in the last century and now. That can not be discussed away ! That is also not only upper atmosphere ! We change the composit of the atmosphere. |
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#15
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| "Josef Matz" <[Only registered users see links. ]> wrote in message news:42f8cf2c$0$6979$[Only registered users see links. ]... especially Bitte, entschuldigen Sie mir. Die Übersetzung von Eiszeit ins Englische ist 'ice age.' Agreed, we appear to be in what is called an 'interglacial' period. Still, the details of the geological record on how temperatures have varied during previous interglacial periods are not very clear. I would like to see the mathematical model which makes the prediction you have voiced, i.e. that 'we should expect a temp decrease.' Current data cannot even reliably determine the duration of such a period, let alone the thermal details of its closing. I was speaking of the global warming events that occurred *before* 8000 years ago. They were, after all, far more accentuated and enduring than what we are seeing currently. can When ice that is floating on water melts, the level of the water does not change. You can demonstrate this to yourself with a glass of ice water. Fill the glass with ice to just *below* the brim, then fill the glass with water until the water reaches the brim - the ice should all float, rising above the brim. Then watch the glass while the ice melts. Ice floats, *displacing* its own weight in water (Archimedes' Principle). When it melts, it *becomes* its own weight in water, exactly replacing the water it had displaced originally. The water level will not rise. level downwards. If you had bothered to examine the chart "Post-Glacial Sea Level Rise" on the page to which I linked, you would have seen that the data came from Santa Catarina, Rio de Janiero, Senegal, the Malacca Straits, Australia, Jamaica, Tahiti, the Huon Peninsula, Barbados, and the Sunda/Vietnam Shelf. That looks pretty 'global' to me. Look at the Picture of Pacific Palisades I referenced: [Only registered users see links. ] There are two tiers of homes built on former beach lines across the middle of the hillside. Both palisade levels represent sea levels during previous interglacial eras. The land locally has not risen (or fallen) in millions of years. The local earth motions involve the 5 million year old San Andreas fault - a lateral strike-slip fault remarkable for its *lack* of vertical displacement. Neither is melting of Antarctic shelf ice, for the same reasons that you should try the experiment I described above. The 'thermal expansion coefficient' argument won't hold water. The thermocline is a level in a body of water which limits vertical mixing due to the differences in density between the upper (warmer, less dense) water and the lower (cooler, and therefore more dense) water. Most (90%) of the ocean lies below the thermocline (about 500 m below the surface), and will not participate in the thermal balance of the globe. In the worst case scenario, global warming will cause the thermocline to drop a few meters. Long term data indicates that the maximum that the sea level could rise, barring a major restructuring of the ocean basins, is about 80 m: [Only registered users see links. ] No. The curve shows *history*. This is what has *already* happened. The curve charts the evolution of sea level as the world passed from an Ice Age (Eiszeit) to the current stage if the Younger Dryas Interglacial. When something rises in one place, something else sinks. What counts is the Conservation of Matter - there is only a finite amount of water on the earth already, and that amount is not likely to increase measurably [barring a cometary impact that would probably kill us all anyway]. It I rather thought I was being *positive.* I guess you have no appreciation for metaphors. It accomplishes nothing to whine about wasting energy or about spewing CO2 into the air. The problem is much larger than that, and even if we totally stopped using fossil fuels and nuclear energy, the world will continue to warm gradually. We could not even make a significant difference in the *rate* of warming. Meine Oma used to tell me that it was a waste of time to worry about anything - either you can do something about the problem or you can't. If you can, then quit worrying and 'get 'er done.' If you *can't* do anything about the problem, you can at least learn how to *live* with it so that it isn't so much of a problem. Either way, worry accomplishes nothing. I wouldn't be building anything expensive and expected to last a long time on sea-level property (like Hong Kong's new airport), though. Tom Davidson Richmond, VA |
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#16
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| "Josef Matz" <[Only registered users see links. ]> wrote in message news:42f928b2$0$6982$[Only registered users see links. ]... to So Friggin' What??? Maybe it can not be discussed away, but it cannot be changed, either. The CO2 is in the air. We can't take it out. Learn to live with it or die. Quit your bitchin' and learn to live with it. Finding someone to blame for it is not going to fix the problem. You whine like a liberal. If you think we control the atmosphere, can you tell us how *you* would take the CO2 out of it? While you are at it, tell us how to get rid of the sulfate aerosols from volcanoes, the uranium and mercury from coal-burning, the radioactive carbon-14 from gamma rays destroying our nitrogen, and all the rest. There is a clever little prayer that makes the rounds in these parts. It is called the Serenity Prayer: "God, Grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference." (The Serenity Prayer is generally thought to have been written by Reinhold Niebuhr) To deal with global warming, you need serenity. It sounds like you are a little too long on courage and short on wisdom. Just remember that, from the perspective of the Earth as a planet, all life is just a skin disease. Tom Davidson Richmond, VA |
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#17
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#18
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| "Josef Matz" <[Only registered users see links. ]> wrote in message news:42f9c7a5$0$6984$[Only registered users see links. ]... <snip repost> I sincerely doubt (again, in my own opinion) that the CO2 content of the atmosphere can be reduced to pre-industrial levels fast enough to significantly reduce the effects of global warming. but then I'm only looking at the historical record of 16,000 years of increasing temperatures and rising sea levels, of which only the last 1% occurred during the Industrial Age - coincidentally, but not *necessarily* consequently. I try to avoid the 'post hoc, ergo propter hoc' fallacy of logic so common in populist 'science' these days. ....albeit an educated one. As a physical chemist, I am very much concerned with cause-and-effect mechanisms, and much of what I see that passes for 'climate research' ignores concepts mechanism for 'guilt by association.' Often climate researchers analyze the same mechanistic relationship between various specific components of the environment and seem to come to totally opposed conclusions. None are considering the gestalt. The climate is so large and complex (from a mathematical modeling perspective) that even Cray supercomputers cannot achieve mechanistic detail and spatio-temporal resolution simultaneously. What remains of which we can be certain is this: the world is getting warmer, and has been for thousands of years. We mortals almost certainly cannot 'correct' this change (not that we can even be certain that the overall effects of the change will be negative). Limitations of technology prevent of from being certain whether the outcome of any intervention efforts on our part will be positive *or* negative (they could be simply futile). Our wisdom prevents us from alleviating the uncertainties regarding the outcome of intervention through classical experimental methods - we only have one world and we don't want to waste it with an ill-understood experiment. Prudence dictates that the most reasonable course is to *anticipate* the effects of the changes that we now recognize are occurring, and prepare ourselves and our realm for the *foreseeable* future. When the sea level *does* eventually rise, I hope to have my posterity standing on a hilltop watching the ocean in the distance, and not standing where Orlando, Florida used to be screaming "My feet are wet and I can't swim!" Auf wiedersehen... Tom Davidson Richmond, VA |
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#19
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| On Wed, 10 Aug 2005 00:10:52 +0200, "Josef Matz" <[Only registered users see links. ]> wrote: snip Aside from theory, much modeling and recent (only) correlation, precisely how _much_ CO2 (ppm) content drives GW has not been shown at all. There are many other factors including our billions breaking wind And, as others have so eloquently stated here already, we can and will cope with the GW, mostly if not all naturally driven or not.. In any case, ocean overfishing, and perhaps its acidity, are undoubtedly greater concerns along with deforestation and desertification by humans. There are just too many humans and livestock for our Earth. Regarding the anthropogenic era, it's been a lot lot longer than one century. Here is one reference: [Only registered users see links. ] [Only registered users see links. ] |
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#20
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| "tadchem" <[Only registered users see links. ]> schrieb im Newsbeitrag news:[Only registered users see links. ]... temperatures try concerned between Cray But we can analyze whats going on and can react by a technology switch. We have to take the effects into account and limit them. So thats just a matter of law and order to limit fossile consumption of energy and adapt the infra structure.There are a lot of fossile ressources in the ground. Mainly coal. And we can adopt our infra structure and let the coal there where it is - in the ground. But propably mankind is too stupid to see this. Then of shure we have to take the full consequences. Maybe we or our children once will ask why? If we have consumed all fossile energies then nothing has changed exept that we have another atmosphere. So we still can avoid this if we react now ! we need renewable energy sources (sun, wind, bio mass) and suitable adopted infra structures. And we should begin now to grow them up and use them in a big scale. Ice age also is something unwished. So if we can avoid this it is not bad. But as i said: We have to find out where the temperatures saturate and if we can live with it. Having this insught it is not understandable why the USA blocks international attempts on reducing the CO2 output. It would be - in my opinion better to participate and support it. outcome (they Tschüß Josef Matz Fulda, Germany |
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