It’s happening! Humanity’s greatest nightmare is already well underway.
Wherever ice is found, appreciable melt is deep-seated, out of control, cascading into the seas shore-to-shore all across the planet. It’s all about too much heat! The trend is in place, and it is accelerating. Global warming is very real.
Thus, the most pertinent questions going forward are: How fast it occurs, and when will coastal cities start erecting levees?
As for erecting levees, the sooner the better in order to keep water out of city streets. How high to build is impossible to answer but most likely, the higher the better. Three feet, five feet, ten feet, twenty feet, thirty feet, who knows? One of those levels might hold (fingers crossed) until the end of this century, assuming fossil fuels are ousted soon, very soon. If not, all bets are likely off.
How is it possible to make such cataclysmic statements?
The answers are found in peer-review science at Antarctica, at the Arctic, at Greenland, at Patagonia, and at glaciers throughout the world. All of the world’s ice is melting at accelerating rates, too fast for comfort.
Ipso facto, seawater levels go up, but unpredictably, and this is why it makes sense to start planning levees around coastal cities. Otherwise, it’s too late once capricious water levels start rising. Nobody knows timing. Nobody.
But, recent studies are foreboding.
Antarctica
Recent studies show Antarctic volume losses accelerating, Fernando S. Paolo, et al, Volume Loss From Antarctic Ice Shelves is Accelerating, Science DOI: 10.1126, Science, Aaa0940, March 26, 2015.
“The overall picture they report online today in Science is grim: The 18-year record suggests that the average loss in volume of Antarctica’s ice shelves across the entire continent has accelerated significantly in the last decade,” Carolyn Gramling, staff writer, Antarctic is Rapidly Losing Its Edge, Science, Latest News, March 26, 2015.