Experts: Global warming means more Antarctic ice

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The Arctic ice responds more directly to warmth. In the Antarctic, the main driver is wind, Maksym and other scientists say. Changes in the strength and motion of winds are now pushing the ice farther north, extending its reach.

Those changes in wind are tied in a complicated way to climate change from greenhouse gases, Maksym and Scambos say. Climate change has created essentially a wall of wind that keeps cool weather bottled up in Antarctica, NASA’s Abdalati says.

And the wind works in combination with the ozone hole, the huge gap in Earth’s protective ozone layer that usually appears over the South Pole. It’s bigger than North America.

It’s caused by man-made pollutants chlorine and bromine, which are different from the fossil fuel emissions that cause global warming. The hole makes Antarctica even cooler this time of year because the ozone layer usually absorbs solar radiation, working like a blanket to keep the Earth warm.

And that cooling effect makes the winds near the ground stronger and steadier, pushing the ice outward, Scambos says.

University of Colorado researcher Katherine Leonard, who is on board the ship with Maksym, says in an email that the Antarctic sea ice is also getting snowier because climate change has allowed the air to carry more moisture.

Winter sea ice has grown by about 1 percent a decade in Antarctica. If that sounds small, it’s because it’s an average. Because the continent is so large, it’s a little like lumping together the temperatures of the Maine and California coasts, Vaughan says.

Mark Serreze, director of the snow and ice data center, says computer models have long predicted that Antarctica would not respond as quickly to global warming as other places. Since 1960, the Arctic has warmed the most of the world’s regions, and Antarctica has warmed the least, according to NASA data.

Scientists on the cruise with Maksym are spending eight to 12 hours a day on the ice bundled up against the fierce wind with boots that look like Bugs Bunny’s feet. It’s dangerous work. Cracks in sea ice can form at any time. Just the other day a sudden fissure stranded a team of scientists until an inflatable bridge rescued them.

“It’s a treacherous landscape,” Vaughan says.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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