WASHINGTON -- The ice goes on seemingly forever in a white flat landscape, stretching farther than ever before. And yet, that spreading ice may be a cockeyed signal of man-made climate change, scientists say.

This is Antarctica, the polar opposite of the Arctic.



Shifts in wind patterns and the giant ozone hole over the Antarctic this time of year -- both related to human activity -- probably are behind the increase in ice, experts say. This subtle growth in winter sea ice since scientists began measuring it in 1979 initially was surprising, they say, but makes sense now.


Ted Scambos of the National Snow and Ice Data Center in Colorado adds, "It sounds counterintuitive, but the Antarctic is part of the warming as well.



And on a third continent, David Vaughan of the British Antarctic Survey said that, yes, what's happening in Antarctica bears the fingerprints of man-made climate change.

"Scientifically, the change is nowhere near as substantial as what we see in the Arctic," said NASA chief scientist Waleed Abdalati, an ice expert. "But that doesn't mean we shouldn't be paying attention to it."

Sea ice always is melting near one pole while growing around the other. But the overall trend year to year is seeing dramatically less ice in the Arctic and slightly more in the Antarctic.

It's most noticeable in September, when northern ice is at its lowest and southern ice at its highest. For more than 30 years, the Arctic in September has been losing an average of 5.7 square miles of sea ice for every square mile gained in Antarctica.

While the Arctic is open ocean encircled by land, the Antarctic -- about 1.5 times the size of the U.S. -- is land circled by ocean, leaving more room for sea ice to spread.


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

The wind works with the ozone hole, the huge gap in Earth's protective ozone layer that usually appears over the South Pole. It's caused by man-made pollutants chlorine and bromine, which are different from the fossil fuel emissions that cause global warming.

