May 18, 2017

Miles of Ice Collapsing Into the Sea

Antarctica
by
Justin Gillis, Derek Watkins, Jeremy White, Jonathan Corum, Evan Grothjan, Graham Roberts, Gregor Aisch, Larry Buchanan, and Rumsey Taylor
,
The New York Times

Excerpted below is Part I of three dispatches from a New York Times reporting trip to Antarctica.


Four New York Times journalists joined a Columbia University team in Antarctica late [in 2016] to fly across the world’s largest chunk of floating ice in an American military cargo plane loaded with the latest scientific gear... We went to Antarctica to understand how changes to its vast ice sheet might affect the world. 

...

Flowing lines on these maps show how the ice is moving.

Ice sheets flow downhill, seemingly in slow motion. Mountains funnel the ice into glaciers. And ice flowing from the land into the sea can form a floating ice shelf.

Glaciers in certain areas have been undercut by warmer ocean waters, and the flow of ice is getting faster and faster.

...

A rapid disintegration of Antarctica might, in the worst case, cause the sea to rise so fast that tens of millions of coastal refugees would have to flee inland, potentially straining societies to the breaking point. Climate scientists used to regard that scenario as fit only for Hollywood disaster scripts. But these days, they cannot rule it out with any great confidence.

...

[A] project to map the structure and depth of the ice shelf in detail, funded by American taxpayers through the National Science Foundation, puts Columbia and its partner institutions on the front lines of one of the world’s most urgent scientific and political problems.

“Our goal is to understand how to predict what’s going to happen to the ice sheets,” said Robin E. Bell, the lead Columbia scientist in charge of the effort. “We really don’t know right now.”

Remote as Antarctica may seem, every person in the world who gets into a car, eats a steak or boards an airplane is contributing to the emissions that put the frozen continent at risk. If those emissions continue unchecked and the world is allowed to heat up enough, scientists have no doubt that large parts of Antarctica will melt into the sea.

But they do not know exactly what the trigger temperature might be, or whether the recent acceleration of the ice means that Earth has already reached it. The question confronting society, said Richard B. Alley, a climate scientist at Pennsylvania State University, is easier to ask than to answer:

“How hot is too hot?”