Come on! It is all of that. The ice shelf is floating but attached. So it is not floating all the way. But, that is not the point, When it breaks, the water does not suddenly raises 4 feet, like one too many cubes in a glass.
It breaks apart and and changes the salinity and the melting accelerates. There is disturbance in the balance, Already, local desalination begins, What happens? Faster melting.
Now that is NOTHING compared to waht is next. The shelves are dramatically thick at the front, 1100 feet, and 200 feet above the water and much thicker as you go landward.
The front of the Ross Ice Shelf has an average thickness of 1100 feet (330 meters), or which the top 100-200 feet (30-60 meters) presents itself as a cliff above the water line. The southern interior of the shelf becomes steadily thicker, reaching 2300 feet (700 meters) in thickness.
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But, that is nothing,
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The Ross Ice Shelf is a
glacier-fed ice shelf.
Eight glaciers flow down from the West Antarctic Ice Sheet (Antarctic Plateau) through the Transantarctic Mountains feed into the Shelf and gradually add bulk to it. At the same time, the freezing of
seawater below the ice mass increases the thickness of the ice from 40 cm (16 in) to 50 cm (20 in).
http://www.eoearth.org/view/article/155788/
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So the Ross especially, but all Shelves, actually are semi-floating. They are piling up on land and they are bulk freezing sea water below. But, they are attached across wide bays and constitute GIANT ICE DAMS. And like any dam, what they hold back is a lot more mass than the dam.
We know that almost all the Ice the world is behind these shelves. They are being held on land and allowed to pile up miles thick of ice inland, Miles thick, being held by fragile dams of ice that are melting, past no return,
47 of these dams hold back from the ocean, most all the ICE in the world.
The
Ross Ice Shelf is the largest
ice shelf in the world with an area of roughly 182,000 square miles (472,000 km²), and is about the size of Spain. This ice
topographic landform is one of the 47 named
Antarctic Ice Shelves.
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Big, big trouble, since there is no way to reverse this, So the shelves are nothing,
But when the dams break, Good Gawd Ya'll! That could wipe us out and make room for new and less clever species,
1500 years is all we have had of many discoveries and 3000 years could be the the total timespan of Scientific Human Civilization, That is about what the Egyptians did, Oh well, just give up, I guess. Oh NO. Do something, to make is so much worse, Good monkeys.
But, you know there are already Elysium outer colonies, and deep Inner Sanctums, for a few, being planned right now.
Oh well, if we could just leave it alone and burn more coal, we would be fine. If we go all nuke, who cares? Ice Age in only 1500 years. We will have piles of hot waste to keep us warm?
Why can we not save mankind from the cold? Why are we just giving in to the Purple Spaceship types that believe the world will be better without humans, That is what they are teaching the kids. I saw it last night on TV.
Say What????
), then when it dries, it will be primed for any vapour or liquid at the optimum level! 
