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0 pointsgcanyon3y ago0 comments

> decades

The ice in Greenland is up to 3000 meters thick, and Antarctica is up to almost 5000 meters. Are you suggesting the net melt could average up to half a meter a year?

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henearkr3y ago

Yes.

"Thousands of years" is clearly wrong, so it is at best several centuries.

About "decades": I'm not saying it will, but that it could.

It is completely in the plausible, and scientists have been proven to be too much conservative, to the great surprise of everyone including themselves.

gcanyonOP3y ago

https://grace.jpl.nasa.gov/resources/30/greenland-ice-loss-2...

That says that loss over the past 19 years is 5 meters; that's less than a millimeter per day. You're proposing a melt up to 500 times faster.

https://en.wikipedia.org/wiki/Greenland_ice_sheet#Future_ice...

That says that the fastest plausible scenario has the ice sheet melting in 1000 years, while the greater likelihood is 10,000 years. And that's if/after we cross temperature thresholds we're not guaranteed to cross.

Nowhere does it entertain the whole thing going in decades. If you have credible sources that argue for the possibility of decades, or even a century or two, you should add that to the page.

henearkr3y ago

The tipping point for Greenland is said to be 2.5°C, and at that tipping point the minimum melting time is said to be 1000 years.

Apart from the fact that all of this relies only on the data we have (we'll discover many more chaotic systems and tipping points, amplifying feedback etc), it also says nothing about what happens at 3.5°C or 4°C warming for Greenland (important precision, as Greenland itself is warming at a much larger rate than the planet globally).

And no, I have no reference to add, only to be cautious and reminding that everybody has been way too much optimistic.

henearkr3y ago

And I want to precise that I am not speaking about Antarctica.

I don't think that Antarctica will lose its ice cover. Only probably its ice shelves, and also some glaciers will shrink, but overall it'll stay white.

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henearkr3y ago

Yes.

"Thousands of years" is clearly wrong, so it is at best several centuries.

About "decades": I'm not saying it will, but that it could.

It is completely in the plausible, and scientists have been proven to be too much conservative, to the great surprise of everyone including themselves.

gcanyonOP3y ago

https://grace.jpl.nasa.gov/resources/30/greenland-ice-loss-2...

That says that loss over the past 19 years is 5 meters; that's less than a millimeter per day. You're proposing a melt up to 500 times faster.

https://en.wikipedia.org/wiki/Greenland_ice_sheet#Future_ice...

Nowhere does it entertain the whole thing going in decades. If you have credible sources that argue for the possibility of decades, or even a century or two, you should add that to the page.

henearkr3y ago

The tipping point for Greenland is said to be 2.5°C, and at that tipping point the minimum melting time is said to be 1000 years.

And no, I have no reference to add, only to be cautious and reminding that everybody has been way too much optimistic.

henearkr3y ago

And I want to precise that I am not speaking about Antarctica.

I don't think that Antarctica will lose its ice cover. Only probably its ice shelves, and also some glaciers will shrink, but overall it'll stay white.

j / k navigate · click thread line to collapse