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A comment on Why Our Intuition About Sea-Level Rise Is Wrong. Parent comment

Re:Why Our Intuition About Sea-Level Rise Is Wrong by Arnt on Tuesday June 02, 2020 @08:57AM (#23390480)
The arctic ice sheet floats. Greenland is an island and Antarctica a continent, both of them surrounded by a little floating ice.

Melting that ice shifts a km-deep layer of ice from a fixed position above nearby sea level to being part of the liquid ocean. This means that it doesn't exert any gravitational pull on the ocean nearby, so the water-covered part of the globe becomes a little bit more spherical. Not much more spherical: The article says 30-50m on the coast of Greenland, which is a very small fraction of the earth's radius.

The 30-50m column of water is distributed elsewhere.

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Re:Why Our Intuition About Sea-Level Rise Is Wrong by Arnt on Tuesday June 02, 2020 @09:09AM (#23390583)
Replying to myself, this implies that near Greenland, the gravitational effect of the ice cap should be ~30 times as big as the moon's (which causes a tide of a little over a meter). Which doesn't seem horribly implausible.
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Re:Why Our Intuition About Sea-Level Rise Is Wrong by emmelaich on Tuesday June 02, 2020 @10:11AM (#23391174)
The moon causes a rise of about 54cm, and the sun around 28cm.

from the wikipedia entry for tides.

https://en.wikipedia.org/wiki/Tide#Amplitude_and_cycle_time

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Re:Why Our Intuition About Sea-Level Rise Is Wrong by Arnt on Tuesday June 02, 2020 @10:15AM (#23391223)
An amplitude of 54cm is about a meter peak-to-peak.
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