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RE: Only nuclear power can now halt global warming



Ok, I'll take one more shot at this.

 

1.   Most of Antartica sits on dry land.  Therefore if the Antartic snow, ice cover were to melt, it would increase the ocean levels.  The artic ice cap floats and its melting is not going to contribute to increases in the ocean's level.

 

2.  The ice started out as snow that was deposited on Greenland.  Over time as more and more snow accumulated the snow on the bottom is converted to ice, mostly by compression, with some contribution due to summer time surface melting.  These ices are used as a means of measuring the weather of thousands and 10's of thousands of years ago through isotope ratio measurements and by examination of pollen deposited with the snow.  

Historically (on a geologic scale) there have been changes in the earth surface (such as plate techtonics resulting in continental drift), but those changes take an extremely long time.  Incidentally if you back in time far enough Antartica was not always covered with ice and apparently had a thriving dinosaur population.  This again was due to continental drift, but that was millions of years ago.  The temperature of the earth has been going up and down probably since its inception.  The last major glaciation period is thought to have ended some 20,000 or so years ago.  The last minor glaciation ended around 1860 or so.  The earth right now is in between glaciation periods (minor or major) and hence is warming.  Why?  I don't think anyone knows for sure.  In the past the earth has been both warmer and colder than it is at present.  Consequently the ocean levels have been both higher and lower than at present.  If you wish evidence, note that most of the archipelagos in the 

!

 Pa!

cific

 are former coral reefs that reached the surface as the ocean surface sank.  Also, acheaologists have recently uncovered some pre-bronze age communities off the coast of Great Britain.  

 

The predictions one sees in the news are mostly due to computer simulations, all of which are based on incomplete knowledge of climate.  And as we all know, GIGO.

 

Hope this helps.



"Riely, Brian P." <brian.riely@ngc.com> wrote:

I want to thank everyone who responded to my question. I know it took some time. My question was meant to address several issues. 1.) Some people claim that the melting of the south pole will cause the ocean to rise by a significant amount, yet Antarctica is floating. 2.) I realize that Greenland is a chunk of land, and as such the ice is not displacing the water. The question then becomes, "how did the ice get there?" If there were a change in the earth surface (land mass) that caused the water to flow to Greenland, stay in the vicinity, and subsequently freeze; and if the earth's surface is roughly the same now as it was then, as the ice melts it should stay in that vicinity. If the accumulation of ice on Greenland is due to water being transported from the ocean, via processes such as evaporation and currents, then we should have a steady decrease in the ocean's level. Of

course, if we get a steady decrease over 10,000 years and a reversal in a 100 years, that could be a major problem. So, it seems to me that before one can say that ice melting in Greenland is going to add water to New Orleans, one has to address how the water got to Greenland. 3.) Sometimes, ostensibly obvious and simple statements are not true. For example, I believe if you ask a typical physicist what would a sphere moving at a velocity close to the speed of light look like to an observer, he would say, " a prolate spheroid." The correct answer is, "a sphere." (to be pedantic: a rotated sphere). It took around 50 years before people realized that the correct answer is a sphere. The scientific literature is replete with errors because the author assumed an "obvious" statement to be true.



Anyway, if someone knows how the water initially accumulated on Greenland, I would be interested.



My apologies for the lengthy e-mail, but I was misunderstood by being too brief.

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