Comment by gmuslera | Hacker News Reader

Comment by gmuslera | Hacker News Reader

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The models assume an steady rate of sea level rise because slow Antarctic ice melting. But if that glacier breaks up (because i.e. the seawater that is rushing now under it) and ends floating towards more temperate latitudes, will melt far faster than predicted, taking maybe months instead of decades.

And you should not think in average sea level rise as some line drawn in the sand. Tides, storms, that gigantic amount of fresh water starting to turning the climate even more chaotic and maybe disrupting some critical ocean ecosystems and currents. Anything that put us further away from the stable situation that led us to establish a global civilization may have very negative impacts.

That's what worries me the most. We have all this "extend the line" projections that say we will see mere cm rises in sea levels in this century.

I am concerned we are missing numerous potential reinforcement loops that might accelerate it. I have a gut feeling that we will see catastrophic coastal floods in the next couple of decades. I cannot shake it.

If it breaks off, it raises the sea level immediately.

It is not like it is floating above sea level and a last snip makes it to fall all at once into ocean water. Or yes, I don't know, I think that probably it will be more complex than that and take its own time (up to months?) for most of it to end there. But probably the process of melting will add a new layer of problems.

Melting ice floating on water does not change the volume of the water at all. Melting will have no impact on sea level at all if the ice is already floating. It does have an impact on albedo.

Shelves and on land glaciers are structurally held up. It's when they enter a floating state that sea level rises, and this is the only time ice can cause a sea level rise. If parts of the shelf are cracked, or otherwise the water is supporting them, then they're already floating and so breaking of the parts that are floating will also have no impact.

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