On May 28, 2025, the tranquil Swiss Alpine village of Blatten in the Lötschental valley faced a catastrophic event when the Birch Glacier collapsed, unleashing a massive landslide that buried approximately 90% of the village under ice, rock, and mud. The disaster was so immense that it registered as a 3.1-magnitude seismic event.
Prior to the collapse, geologists had observed increasing instability in the glacier, prompting authorities to evacuate the village’s 300 residents on May 19. Even livestock were airlifted to safety. Despite these precautions, a 64-year-old man remains missing, and search efforts have been suspended due to hazardous conditions.
The landslide deposited an estimated 10 million cubic meters of debris, blocking the Lonza River and forming a temporary lake that poses additional flood risks to downstream communities.
Experts suggest that the collapse was likely triggered by a combination of factors, including the accumulation of rockfall on the glacier and the degradation of permafrost due to rising temperatures. Christophe Lambiel, a geologist at the University of Lausanne, noted that the permafrost, which acts as a “glue” holding mountain rock together, has been weakening over the past 10 to 15 years, contributing to the glacier’s instability.
Mylène Jacquemart, a glaciologist at the Federal Institute of Technology Zurich, emphasized that while it’s challenging to attribute a single event directly to climate change, the ongoing warming trends are undoubtedly making high mountain environments more unstable.
Swiss President Karin Keller-Sutter visited the disaster site, pledging government support for the affected residents and emphasizing the need for enhanced monitoring of glacial regions. Emergency services, including the Swiss army, have been deployed to manage the aftermath and monitor the newly formed lake for potential flooding.
Authorities have also issued warnings to nearby villages, such as Gampel and Steg, advising residents to prepare for possible evacuations should the situation worsen.
