Swiss glacier collapse: Climate change and retreating glaciers around the world

The landslide that buried most of a Swiss village this week is focusing renewed attention on the role of global warming in glacier collapses around the world and the increasing dangers.

- By TAMMY WEBBER Associated Press

How glaciers collapse — from the Alps and Andes to the Himalayas and Antarctica — can differ, scientists say. But in almost every instance, climate change is playing a role.

In Switzerland, the mountainside gave way Wednesday near the village of Blatten, in the southern Lötschental valley, because the rock face above the Birch Glacier had become unstable when mountain permafrost melted, causing debris to fall and cover the glacier in recent years, said Martin Truffer, a physics professor at the University of Alaska Fairbanks who studies how glaciers move.

While the debris insulated the glacier and slowed melting, its weight caused the ice to begin moving — which accelerated dramatically a few weeks ago. Authorities ordered the evacuation of about 300 people, as well as all livestock, from the village in recent days, "when it became clear that there’s a whole mountainside that’s about to collapse," said Truffer, who is from Switzerland.

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