In March 2002 scientists watched the Antarctic's 500-billion-ton Larsen B ice shelf shatter into thousands of tiny icebergs before their eyes. In summer 2002 a three-million-ton chunk of ice broke off the Maili Glacier, high in Russia's Caucasus Mountains. It roared downhill, burying the village of Karmadon in 500 feet (150 meters) of frozen debris.
Earlier this year University of Colorado glaciologist Konrad Steffen and his team discovered that ice shelves jutting into the ocean from Greenland's Petermann Glacier were 150 feet (45 meters) thinner than last year. And a Montana State University study revealed that the state's Glacier National Park has lost more than 110 of its glaciers and snow and ice fields over the past century—and the remaining 40 are shrinking.
Warming climate seems to be melting glaciers across the globe. Researchers are trying to better understand how glaciers affect and are affected by climate—and are trying to create better mathematical predictions for how fast glacial ice moves.
The big drive is to better predict how climate change may affect the evolution of the polar ice sheets. The greatest concern focuses on the western Antarctic: Antarctica holds 90 percent of the world's fresh water.
Melting glaciers add fresh water to the oceans and speed the seaward movement of ice and an influx of fresh water into the ocean. "Faster ice flow means sea level rises," said Richard Alley, a glaciologist at Pennsylvania State University in University Park.
The worry is that continued glacier melt could swamp coastal areas—and alter crucial Atlantic Ocean currents that regulate climate: The amount of fresh water in oceans affects how much of the sun's heat can be recycled to warm the air.
"If all the ice on Earth melted, the ocean would rise 200 feet [60 meters]," Alley said.
Subterranean Laboratory
To answer some of these glacier questions, researchers led by Iowa State University geologist Neal Iverson have flown to the Arctic in Norway numerous times over the past five years on a series of glacier-study expeditions.
When they arrive at the top of the world, the scientists slip into rubber boots, don hard hats outfitted with miner's headlamps, and descend into a dark, damp, freezing underground laboratory. They live and work there for weeks, underneath—and inside—the Svartisen Ice Cap.
Statkraft, Norway's state power company, created the lab as part of a 60-mile (100-kilometer) subterranean maze of tunnels and cavelike rooms they burrowed into the rock beneath the glacier back in 1993 to generate hydroelectric power from glacial meltwater.
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