Print

Email story

Comment

Letter to the editor

Sea-level rise poses a threat to society

A 3-foot increase in sea level could make 60-million refugees.

By WASHINGTON POST
Published July 17, 2007

Few consequences of global warming pose as severe a threat to human society as sea-level rise. But scientists have yet to figure out how to predict it.

And not knowing what to expect, policymakers are hamstrung in considering how to try to prevent it or prepare for it.

To calculate sea-level rise, researchers need to understand the behavior of the major ice sheets that cover Greenland and Antarctica.

The disintegration of one would dramatically raise the ocean. But while computer models now yield an increasingly sophisticated understanding of how a warming atmosphere would behave, such models have yet to fully encapsulate the complex processes that regulate ice sheet behavior.

"The question is: Can we predict sea level? And the answer is no," said David Holland, who directs New York University's Center for Atmosphere Ocean Science. Holland, an oceanographer, added that this may mean researchers will just have to watch the oceans to see what happens.

But because so much is at stake - a 3-foot increase in sea level could turn 60-million people into refugees, the World Bank estimates - ice-sheet modelers are working furiously to try to solve how these sheets accumulate and lose mass.

Michael Oppenheimer, a Princeton University professor of geosciences, figures that if the Greenland ice sheet disintegrates, sea level would rise about 23 feet. If the West Antarctic sheet melts, it could add 16 feet.

"If either of these ice sheets were to disintegrate, it would destroy coastal civilization as we know it," Oppenheimer said.

Researchers have convened two major meetings this year in an effort to develop sophisticated models to inform policymakers about the potential dangers.

[Last modified July 17, 2007, 00:48:59]