Quote:
Originally Posted by NeilBlanchard
Did you read the link? It is all about how measuring mountains above sea level is not very accurate, in telling us how tall they actually are above the center of the earth - or how close they are to space.
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Yes, I read the article - skimmed it, rather, because I'd seen similar before. The problem is that it's what I might call junk science news, like "supermoons": something that is factually true, perhaps even sort of interesting, but absolutely irrelevant for any practical purpose.
Just to note: those equatorial mountains aren't closer to space, because space is defined either as lack of atmosphere (for practical purposes) or for legal purposes as the Kármán line, which is 62 miles/100 km
above sea level. And sea level, of course, is defined as the approximately oblate spheroid that's a gravitational equipotential surface.
The same principle holds for Antarctica (and Greenland, or anywhere there are tall mountains, deep basins, or rocks of different density). Yes, they have gravity, but that gravity defines the (non-spheroidal) equipotential surface that is sea level. So the water there is not 8000' higher: it's all at the same* gravitational potential.
*Neglecting the small effects of winds, currents, and the like.