Correction to This Article
This article about ice loss in Antarctica incorrectly says that Mount Kilimanjaro is in Kenya. It is in Tanzania.
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Escalating Ice Loss Found in Antarctica

Part of the Larsen B ice shelf in Antarctica is shown after its rapid collapse in early 2002, which was attributed to global warming. Ice sheets elsewhere on the continent that were considered stable are melting, scientists have found. At right, satellite images show the Sheldon Glacier in western Antarctica in, from top, 1986, 2001 and last October.
Part of the Larsen B ice shelf in Antarctica is shown after its rapid collapse in early 2002, which was attributed to global warming. Ice sheets elsewhere on the continent that were considered stable are melting, scientists have found. At right, satellite images show the Sheldon Glacier in western Antarctica in, from top, 1986, 2001 and last October. (Kpa/mediacolors)

The new findings come as the Arctic is losing ice at a dramatic rate and glaciers are in retreat across the planet. At a recent annual meeting of the American Geophysical Union, Ohio State University professor Lonnie Thompson delivered a keynote lecture that described a significant speed-up in the melting of high-altitude glaciers in tropical regions, including Peru, Tibet and Mount Kilimanjaro in Kenya.

Thompson, who has studied the Quelccaya glacier in the Peruvian Andes for 30 years, said that for the first half of that period, it retreated on average 20 feet per year. For the past 15 years, he said, it has retreated an average of nearly 200 feet per year.

"The information from Antarctica is consistent with what we are seeing in all other areas with glaciers -- a melting or retreat that is occurring faster than predicted," he said. "Glaciers, and especially the high-elevation tropical glaciers, are a real canary in the coal mine. They're telling us that major climatic changes are occurring."

While the phenomenon of ice loss worldwide is well documented, the dynamics in the Antarctic are probably the least understood. Glaciers and ice sheets are sometimes miles deep, and researchers do not know what might be happening at the bottom of the ice -- but it clearly is being lost along the peninsula and West Antarctic coast.

Rignot theorizes that the warmer water of the Antarctic Circumpolar Current is the cause. Douglas Martinson, a senior research scientist fellow at the Lamont-Doherty Earth Observatory of Columbia University, has studied the issue and agrees.

Martinson said the current, which flows about 200 yards below the frigid surface water, began to warm significantly in the 1980s, and that warming in turn caused wind patterns to change in ways that ultimately brought more warm water to shore. The result has been an increased erosion of the glaciers and ice sheets.

Martinson said researchers do not have enough data to say for certain that the process was set in motion by global warming, but "that is clearly the most logical answer."

Pachauri, the IPCC's chief of climate science, will visit Antarctica this week with Norwegian Prime Minister Jens Stoltenberg to get a firsthand view of the situation.

"You can read as much as you want on these subjects, but it doesn't really enter your system. You don't really appreciate the enormity of what you have," Pachauri said.


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