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0 pointskoops7y ago0 comments

Unfortunately no, not here. The metaphor I've heard is continent as couch cushion: the glacier was "sitting" on the upper part of North America, pushing up the edges. Now that weight is gone, the coasts are dropping slightly.

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jackcarter7y ago

Ah, that’s interesting and believable. Do you know where you heard that?

I found this article, which talks about a slightly different effect: If Antarctic ice melts more quickly than arctic ice, then the Antarctic land rebound will shove southern-hemisphere water north, raising sea levels in the northern hemisphere. The opposite effect happens if arctic ice melts before Antarctic ice.

https://www.theguardian.com/commentisfree/2018/oct/01/cities...

wcoenen7y ago

The article doesn't even mention the effect of gravity, which is also significant. Ocean water is currently gravitationally attracted to the ice caps, and when an ice cap disappears, all that "bunched up" water will spread around the globe. This effect reduces sea level rise in a large area around the ice cap, and increases it everywhere else.

This other article in The Guardian does mention it: https://www.theguardian.com/environment/ng-interactive/2018/...

koopsOP7y ago

Here the Woods Hole oceanographers talk about it without the couch analogy:

https://www.whoi.edu/news-release/why-is-sea-level-rising-hi...

darkerside7y ago

If it's sitting on top, wouldn't it push down? Or do you mean upper as in north?

zaroth7y ago

It’s fantastic and even mildly hilarious that this is a real effect at such a massive scale.

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