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Comment by revax | Hacker News Reader

FYI melting iceberg do not cause sea levels to rise, but glacier do. An ice cube melting in your glass water do not rises the level.

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Yes, fair point. I was speaking inexactly. I of course meant glaciers or perhaps icebergs which break off of glaciers.

I don't think that this is technically true, since icebergs are made from fresh water and they melt in the salt water of the ocean. Fresh water is less dense, so it will take up a larger volume than that of salt water.

Where does the additional density come from that wasn't there already when the iceberg was floating?

The amount of salt water displaced by the fresh water ice is equal to its weight, but the melted fresh water will take up a slightly larger volume than the displaced salt water. It is small, but calculable.

From what I remember reading, if all of the floating sea ice on the globe were to melt right now, sea levels would rise by about 5 centimeters.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201...

Yes you are right but this is not enough to have a meaningful impact.

the thermal expansion coefficient of liquid water explains the rise

That would be an effect of ocean warming. The melting itself occurs at a nearly constant temperature and is correlated with, but not causative of, the ocean warming.

But, perhaps you're trying to point out that the thermal expansion of the oceans has a greater impact on sea level rises than the correlated problem of glacier melting.

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