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Comment by mikestew | Hacker News Reader

I still don't see where six feet is coming from.

I read $SOMEWHERE recently that the the worst case scenario predicted six feet. But that's, IIRC, if we do absolutely nothing, the methane in the Arctic is all released, and Greenland melts. The more likely scenario is somewhere from 1-3 feet.

So unless memory fails me, the article didn't just pull it out of its arse, but a source would've been nice rather than just throw a number out there with no backing whatsoever.

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If Greenland melts, you get 6 meters (20 feet).[1]

1: https://nsidc.org/cryosphere/quickfacts/icesheets.html

Greenland is melting.

https://www.washingtonpost.com/news/energy-environment/wp/20...

I found it curious that this research only went back 450 years or so, since that takes you back to just before the Little Ice Age, a time of unusually cold temperatures, at least in the Northern Hemisphere. One wonders what they would have found had they kept going further back in time.

BTW, they already know that a lot of the melting in Greenland is from the bottom up (geothermal) rather than from the top down. But of course you don't hear too much about that, do you?

https://www.newsweek.com/puzzling-heat-deep-inside-earth-mel...

Check this out for real time data about the Greenland ice mass budget. (Spoiler: Greenland is not melting)

https://www.dmi.dk/en/groenland/maalinger/greenland-ice-shee...

You are right, it's not losing mass through melting.

But it is losing mass when iceberg calving is accounted for.

"Over the year, it snows more than it melts, but calving of icebergs also adds to the total mass budget of the ice sheet. Satellite observations over the last decade show that the ice sheet is not in balance. The calving loss is greater than the gain from surface mass balance, and Greenland is losing mass at about 200 Gt/yr."

Edit: And i thought this article on the scale of a gigaton of water was interesting as well:

https://www.washingtonpost.com/news/energy-environment/wp/20...

200 Gt = 0.007% of the ice mass of Greenland.

Or 0.5mm sea level increase (from your link).

Here's a (the?) source for 3' that Bloomberg omitted https://www.coast.noaa.gov/states/stories/data-models-sea-le...

Misreading the link - as many newspapers have done, and it's wrong absent further data - results in 6'

EDIT: As noted by Accipitriform I made the same mistake I pinned on many newspapers.

Actually that link makes no prediction at all about how much sea levels will rise. It merely looks at the impact if the sea level were to rise by the given amounts.

I read $SOMEWHERE that most sea level rise is/will be due to thermal expansion of water, not melting ice.

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