There are quite a few ideas being bandied about for dealing with sea-level rise as it occurs. But in case you were set on freezing the water and transferring it to Antarctica, be forewarned: Scientists also thought of this and are squelching it in advance.
That is, a study at Germany's Potsdam Institute for Climate Impact found that although it's true that water pumped from the sea onto Antarctica would freeze into solid ice, its weight would hurry up the flow of ice into the ocean at the coast of that lower continent.
In order to keep the ice for a millennia and not rush off the continent and into the sea, any successful effort would need to pump the ice a minimum of 700 kilometers inland. Doing so would use quite a lot of energy: More than a tenth of the current supply of annual global energy would be required in order to maintain a balance of the present sea-level rise rate.
"We explored a way to at least delay the rise of sea level we can no longer avoid by even the strictest climate-change mitigation strategies. This is estimated to reach about 40 cm by the end of the century," said Katja Frieler, the study lead author. "Our approach is definitely extreme, but so is the challenge of sea-level rise."
At the current rate of warming, sea level rise could occur at a rate of more than 130 centimeters by 2100. Effects from the rise might be greater for poor coastlines than for those with governments that can afford to make changes, too; for that reason, the study authors say they'd especially like to work out a universal solution.
"Local adaptation, for instance building dikes, will not be physically possible or economically feasible everywhere," said Frieler. "Protection may depend on your economic situation - so New York might be saved, but sadly not Bangladesh, and this clearly raises an equity issue. Hence the interest in a universal protection measure. We wanted to check whether sacrificing the uninhabited Antarctic region might theoretically enable us to save populated shores around the world."
Using computer simulations of Antarctica, the study authors looked at an ice-dynamics perspective. They found that ocean water put on the surface of ice (which is constantly moving) can only be delayed, not stopped. Managing to pump the ice so far inland, up to a height of 4,000 meters high, would require an overly challenging engineering effort. It would require huge amounts of energy.
It doesn't stop there, either. If scientists tried to save energy by using Antarctica's very windy climate to generate power, they would need to build 850,000 plants there for generating wind energy, the study found.
"The magnitude of sea-level rise is so enormous, it turns out it is unlikely that any engineering approach imaginable can mitigate it," said study co-author Anders Levermann, a scientist at Columbia University's Lamont Doherty Earth Observatory. "Even if this was feasible, it would only buy time - when we stop the pumping one day, additional discharge from Antarctica will increase the rate of sea-level rise even beyond the warming-induced rate. This would mean putting another sea-level debt onto future generations."
Taking steps to move ice inland on Antarctica would also damage sensitive coastal environments on the continent.
The study findings were published in the journal Earth System Dynamics.
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