Were all of Greenland's ice cap to melt, it would raise sea levels by tens of feet. New ice coring that has reached through the ice and found evidence of vegetation underneath, more recently than once thought, shows that it is indeed possible.

Greenland’s Ice Sheet Isn’t As Solid as We Thought – and That’s Terrifying
New evidence shows Greenland's ice sheet once melted completely, revealing a tundra below. This suggests increased vulnerability to climate change and significant potential sea level rises. New research provides the first direct evidence that the center, not just the edges, of Greenland’s ice she
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