Avalanche!

摘要

Many of those who lost their lives in Galtuer on 23 February 1999 never knew what hit them. Until that afternoon, hundreds of thousands of tonnes of snow lay banked on the high ridges that flank the small ski resort in the Austrian Alps. Then the banks suddenly collapsed, unleashing an avalanche that swept away buildings and killed more than 30 people. Similar tragedies struck across the mountain valleys of Austria, Switzerland and France, where five metres of snow had fallen in the preceding weeks. In total, more than 100 people were killed, and the economic damage topped EUD1 billion (US$1.1 billion). The death toll for this disaster was exceptional, but avalanches kill every year. Only last month, 14 skiers and hikers died near Rogers Pass in British Columbia, Canada. A similar number have so far been killed in the Alps this winter. To counter the threat, studies of the layers of snow and the dynamics of avalanches have intensified in recent years. Researchers cannot eliminate the hazard but, by mapping the most dangerous areas and understanding the physics involved, they can issue timely warnings that could save lives.