Overview

• Swiss military engineers are removing millions of tons of rock and ice and pumping out a lake formed by the glacier’s natural dam on the Lonza River.
• Preventive evacuation of 300 residents in Blatten prevented large-scale casualties, though one person remains unaccounted for.
• Glaciologists say cascading rockfalls from the Petit Nesthorn and probable permafrost thaw triggered the glacier’s sudden collapse.
• The Birch glacier’s rare advance—fueled by the weight of accumulated debris on a steep slope—amplified the slide’s force.
• Experts warn that rapidly melting Himalayan glaciers and gaps in monitoring capacity in Asia pose comparable risks and demand stronger early warnings.