Polar distress

PUNTA ARENAS, Chile – Scientists looking southward from the tip of South America, over steel-gray waters toward icy Antarctica, see only questions about the fate of the planet.

Now that one mammoth Antarctic ice shelf has collapsed into the ocean, when might another, bigger one crumble and slip into a warming sea? In 1,000 years? In 100 years? Sooner?
“People don’t have the answer to the question yet – what the probability is of that collapse, if any,” said scientist Gino Casassa. “But there’s some indication of instability.”

Fears of global warming arise as the Kyoto Protocol finally takes effect this Wednesday. The international accord seeks to reduce industrial emissions of carbon dioxide and other “greenhouse gases” without the world’s largest emitter, the United States.

Casassa and fellow Chilean researchers have visited Anarctica to trace the effects of global warming and brought back some potentially unsettling news.

On a two-month round-trip trek by snow tractor to the South Pole, they pointed their sophisticated radar at the ground and found that the West Antarctic Ice Sheet may be thicker than thought, many hundreds of feet thicker in parts.

Glaciologists like Casassa worry most about that western ice sheet, half a continent of frozen water believed enough, if gradually melted, to raise ocean levels worldwide by about 15 feet.

Philadelphia Inquirer