Global ChangeIntersection of Nature and Culture

Most people are aware that the loss of ice from land masses like Greenland and Antarctica have the potential to raise sea level.  One of the current concerns about polar ice loss is that as sea level rises, ice loss is accelerating.How does this work?  Much of the ice along the margins of these land masses is what we call “grounded” –it physically stuck on the rough land lying under the coastal ocean.  Imagine a block of ice sitting on a dinner plate, which, in turn, is sitting on something rough like a carpet.  If you tilt up one end of the plate just a bit, gravity causes the ice to slide off until it hits the carpet, where it gets stuck.  Most of the ice block remains on the plate but a bit is wedged (grounded) into the carpet.  This is what basically happens to many of the glaciers flowing off the Greenland and Antarctic land masses.

Here’s the bad news:

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