No Longer The Frozen North?

melting ice cap, global warming iceberg
The spring whale hunt on the Arctic ice edge has sustained Eskimo life for thousands of years. Now it has turned potentially deadly for the hunters of the Iniaput tribe, reports CBS News Correspondent Jerry Bowen.

Two weeks ago, the Arctic ice pack near Barrow, Alaska, broke apart, trapping a large whaling party. The mishap prompted a half-day long helicopter rescue.

Whaling captains say the ice is half what it used to be just ten years ago.

John Nujsunginya, a whale crew captain, said: "Nowadays we're lucky to see it four feet thick. It's very dangerous out there right now."

A thousand miles north, at the North Pole itself, scientists say the Eskimo are right. The ice cap is thinning.

"The ice has been reduced in thickness by 40 percent and this is something you can immediately see when you go out on it," said oceanographer Jamie Morison.

Morison is looking at how the top-of-the-world ocean regulates global climate, research funded by the National Science Foundation. He's already found the water is saltier and circulating faster than expected.

CBS News sent a camera with the expedition, and Morison spoke to us via satellite telephone:

Bowen: What are you seeing?

Morison: This change in circulation carries the ice out of the Arctic Ocean faster than it used to. And with that, its average thickness is decreased. So it isn't that heat has been melting the ice. Its that it spends less time in the Arctic Ocean."

And based on data recovered from underwater monitoring arrays, Morison suspects the faster currents and thinner ice are due to atmospheric changes.

"Whether this is global warming related to human activity or just a large natural action, we don't really know," he said.

But the anecdotal evidence off Alaska and across the Arctic is hard to ignore. There are even dire predictions about the survival of the world's 27,000 polar bears if their habitat melts away.

For now, it's the human hunters who are scrambling in a world that seems less predictable by the day.