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#1
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| I see a great many articles such as this one; [Only registered users see links. ] which vigorously point out that there is a global warming trend well underway. I have been searching for some insights into the cause of this trend. Is it just a normal progression along the ice age cycles, or is it truly a result of human intervention? Can anyone point me to some meaningful information on the ice age cycles that have occurred over the geologic past. It seems this planet has gone through these ice age - global warming cycles about every 20,000 years, and the global warming we are now observing is reasonably congruent with the cyclical variations that occurred well before humans had any part of it. How suddenly can we expect the global warming to end and a drop into a deep ice age part of the cycle occur? Is this just a few years into the future, or a few thousand years? |
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#2
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| Dear Gordon: "Gordon" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... You'll find that cases can be made either way. Yes it appears that we averted the most recent glaciation period. Yes it appears that global warming is occuring. No it is not clear that a 0.05% increase in global CO2 emissions (if that) due to the activities of Man is any significant effect. Yes the butterfly effect (eg. chaotic system responses to an upset) could magnify any effect into a global change. Yes the Sun is a variable star, and its emissions of energy vary. Change happens, and Mankind will adapt or be replaced. If it gets bad, we can always spray finely-divided water in the upper atmosphere, in excess of what we do with high flying aircraft ("global dimming" if you want to do a search on the concept). David A. Smith |
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#3
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| "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:[Only registered users see links. ]> wrote in message news:EevJe.290176$Qo.146693@fed1read01... FWIW, [Only registered users see links. ] shows that the mean sea level has risen about 20 cm in the past century. [Chart at [Only registered users see links. ] ] It *also* shows that the mean sea level has risen about 120 m in the last 16,000 years, an *average* rate of 75 cm per century, most of which occurred during the period *before* we had any cities or 'civilization.' In terms of global warming effects, things have actually been comparatively calm since we settled down and started farming, except for the occasional Plinian volcanic eruption with the power (VEI 5 or greater) to cool the globe for a while: [Only registered users see links. ] You are absolutely correct, David. Change happens. It does no good the try to blame it on anybody or anything in particular. The smart thing to do is to learn enough to figure out what is *going* to happen and plan, prepare, and adapt for it. As my late grandmother used to say - "Adapt or Die." Tom Davidson Richmond, VA |
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#4
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| "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:[Only registered users see links. ]> wrote in message news:EevJe.290176$Qo.146693@fed1read01... For the 3 days after 9/11, when all air traffic over US was suspended, the mean diurnal temperature range increased by over 1 degree. Where contrails would normally be most frequent, the change in mean DTR was greatest. I don't think its clear yet whether contrails are a cause or a cure for 'global warming' - I suspect there is a case for them being associated with a reduction in night time heat loss which might actually be worse than any assoociated reduction in daytime insolation. |
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#5
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| Dear OG: "OG" <[Only registered users see links. ].uk> wrote in message news:[Only registered users see links. ]... I personally hold high altitude water-producing combustion responsible for a very large share of whatever reduction in ozone levels are actually attributable to Mankind. One very important pathway to the production of ozone is using N2* as a "temporary placeholder" for an oxygen atom, until visible light and passing O2 molecule accepts it. Water at altitude provides a more stable result than ozone, namely NOx. And air-breathing engines consume oxygen to boot, reducing the availability of oxygen for both scission and recombination. Migration of gasses from lower to upper atmosphere is not terribly fast. Horizontal transfer is quite fast... I recall that White Sands put a missle up some years ago, and something about the exhaust from it made for a most beautiful pre-sunrise light show, that was easily hundreds of miles wide... and dissipated in tens of minutes. However much science supports me in that... ;>) No, I don't think artificially-produced contrails are a good idea. David A. Smith |
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#6
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| Dear tadchem: "tadchem" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... .... <POKING A LITTLE FUN> Then why in the world did you move to a low-lying area? Edgar Cayce gave Virginia the blessing for the lifetime of his child(ren)... not eternity! <END POKING> David A. Smith |
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#7
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| "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:[Only registered users see links. ]> wrote in message news:BwAJe.295267$Qo.67285@fed1read01... 100 m above current MSL is hardly 'low-lying'. The Holy Saint Edgar blessed Virginia Beach. He also said that Atlantis would rise again in the 1960's. Frankly. I would be more concerned about a little earthquake on La Palma. Tom Davidson Richmond, VA |
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#8
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| "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:[Only registered users see links. ]> schrieb im Newsbeitrag news:EevJe.290176$Qo.146693@fed1read01... No definitively not. The strong temp increase is not explainable with ice time changes. It is man made. But of shure the earth had much wormer times than now. Now it can happen that within a few years the ocean level increases by about 5 meters. In the period of one century or more it can be 35 meters (some say 65 meters) if the trend is not stopped. If all ice on the globe would be molten, we dont know where the average temperature saturates. Too much unknowns. So this probably should us more give a bad feeling because we do not know where the journey goes. |
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#9
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| "Josef Matz" <[Only registered users see links. ]> wrote in message news:42f776e8$0$6977$[Only registered users see links. ]... Is 'ice time' measured with a snow-filled hourglass? So who were the 'men' who made those other global warming events occur? about Take a look at the sea level record: [Only registered users see links. ] From 14,500 BP to about 14,000 BP the most dramatic increase in sea level since the Pleistocene occurred. Mean sea level rose about 30 m in 500 years. At that rate a 5 m increase would take only about 80 years. Is there really that much ice left in the polar regions? The remaining ice in temperate and tropical zones is negligible. I smell hyperbole here. Look at Pacific Palisades, California: [Only registered users see links. ] The two middle tiers are ancient coastlines recording the highest levels the Pacific ocean has reached in many millions of years. If I 'got a bad feeling' every time I didn't 'know where the journey goes,' I'd dread getting out of bed every morning. Carpe diem! Carpe mundi! Grow yourself a backbone. Become a vertebrate. Learn to breathe air. It will make it easier to climb out of the ooze into tomorrow. Tom Davidson Richmond, VA |
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#10
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| "tadchem" <[Only registered users see links. ]> schrieb im Newsbeitrag news:[Only registered users see links. ]... ice No it is not. But the CO2 emissions are manmade, waste of energy especially in the USA. We are at the end of a small warm time in between ice times. Normally we should expect a temp decrease. As i told you the usage of fossile energies (coal, gas oil) since the industrialisation 1850 is about the beginning of it) The 5 meters are based on the assumption that the shelf ice on soth pole can melt rather fast. Shelf ice is ice which lies in flat ocean regions. I doubt on that globally. Localy also the country can move up and downwards. Are you shure it was a global change ? So if this is true we can see what might be the future ? ice Melting of north pole is not increasing the water level. South pole and green land (5m).are main contributions. In a scenario with full molten ice also the thermal expansion coefficient of water has effects. Maybe your curve shows what happens if all ice is molten with respect to this the thermal expansion coefficient ? Then you would have a model for whats going on then. It would be interesting to have the environment temperatures of such epochs. [Only registered users see links. ] oast%20by%20californiaimage.htm the Also the continents may rise and fall, but that of shure can not happen within a few hundred years. do goes,' No my feeling os not bad. Some countries might vanish from the country map, other regions might become usable. But old countries like Bangla Desh, Netherlands might change to some towers looking out of the water. New York or Boston for example will also look a little otherwise than today if sea level 35 meters higher. And even Berlin will be located on the coast. The environmental changes (deserts, storms) will cause millions over millions of victims. Why must you make such negative suggestions. Your country is also affected or ? |
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