Speeding Glacier

Science World, Oct 4, 1999 by Van Neistat

If Hollywood director James Cameron ever makes a sequel to Titanic, he might need to check out Prince William Sound near Anchorage, Alaska. There, the Columbia Glacier--the fastest moving glacier (large river of ice) in the world--is calving, or breaking off into the sea, faster than ever. And the result could be ship-gouging icebergs in one of America's busiest oil ports.

The 55 kilometer- (34 mile-) long glacier is sliding into the sea at a rate of 35 meters (115 feet) per day, claims a study by Tad Pfeifer, a University of Colorado glaciologist (glacier scientist). At that rate, the glacier will be completely waterlogged in four years.

Glaciers move like slow rivers. And, like ice cubes, parts of glaciers float in water. "As a glacier flows into water deep enough to make it float, the tip breaks off," Pfeifer said. "As they float, glaciers lose contact with land, which makes them flow even faster." Since the Columbia Glacier is moving at record speeds, it's breaking off a larger-than-normal load of ice chunks into Prince William Sound.

Why is Columbia advancing so fast? Some scientists claim it's because Earth is in a natural heating cycle. About 2 million years ago, much of Earth shivered in the grip of an Ice Age, or geological period of extreme cold. So glaciers covered most of the planet surface. While the ice mostly melted about 10,000 years ago, the Columbia Glacier, along with other glaciers in Alaska, Canada, and northern Europe, are Ice Age leftovers.

Now a global warming trend has melted the bottom layer of Columbia and accelerated its pace, plunging it into the sound at record speeds. But global warming associated with human activity, like car exhaust, isn't what's making glaciers lose their cool, says Pfeifer. It's simply Mother Nature doing her thing!