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Comment by DrScump | Hacker News Reader

  Will it make the oceans rise? barely (0.1 mm)

Where do they get that? The melting of already-floating icebergs has zero net effect on sea lever or (liquid) water volume. It would take a huge amount of added water to make even a .1mm effect worldwide.

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The article explains that an iceberg of this size would add 3 mm to sea levels if it had not already been floating in the ocean. I'm curious, too, about the 0.1 mm.

EDIT: Apparently the 0.1 mm change is due to the difference in salinity. https://phys.org/news/2005-08-ice-sea.html

Could be thermostatic sea level rise: the water will spread to warmer parts of the ocean and expand.

Thermal expansion is the primary source of sea level rise in general, isn't it?

Melting of an ice cube in a glass of water doesn't change the water level. It was in the highschool physics cirriculum where I'm from.

This won't hold true when melting a _freshwater_ ice in _salty_ water, but I too doubt the change will be anywhere near 0.1mm

It is the melting of the ice on above the water surface minus the difference in volume of the ice below the surface and the water it would become. Someone else mentioned that if the entire iceberg were melted it would cover California with 4.5in of water. If you divide that by the ratio of the ocean area to the area of California you get 0.13mm. I'm not sure how much is above the water vs below the surface but it seems like a reasonable thing for them to estimate.

Just enough of it is above the surface to account for the change of volume when it melts. Or equivalently, it displaces its own weight in water.

Hmm. I see what you are saying. So they probably did do the calculation I referenced but I agree it is probably faulty. However, there is some rise from melting: https://www.newscientist.com/article/dn18841-melting-iceberg...

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