{"id":23414,"date":"2026-03-02T23:20:42","date_gmt":"2026-03-02T23:20:42","guid":{"rendered":"https:\/\/www.europesays.com\/ch\/23414\/"},"modified":"2026-03-02T23:20:42","modified_gmt":"2026-03-02T23:20:42","slug":"the-2025-blatten-disaster-in-the-swiss-alps-followed-exceptional-warming-and-highlights-the-vulnerability-of-people-and-heritage-in-glaciated-landscapes","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ch\/23414\/","title":{"rendered":"The 2025 Blatten disaster in the Swiss Alps followed exceptional warming and\u00a0highlights the vulnerability of people and heritage in glaciated landscapes"},"content":{"rendered":"

The complex, interacting and multi-seasonal rock mechanical, glacial and hydrological processes that led to the Birch glacier\u2019s detachment are now under detailed investigation. While the statistical basis for evaluating causes of large glacier detachments remains limited8<\/a>, global warming may be increasing the frequency and intensity of such events9<\/a>,10<\/a>. Alpine permafrost in Switzerland lost about 15% of its ice between 2015 and 2022 CE11<\/a>, and hot summers like those of the past decade have irreversible consequences as the thickness of the active layer that thaws in summer increases12<\/a>. In the case of Birch glacier, permafrost degradation of the Kleines Nesthorn summit region around 3335\u2009m asl, probably enhanced rockfall on to the lower and more voluminous section of the glacier, contributing to its gravitational instability and eventual collapse.<\/p>\n

Comparable events have occurred in the Swiss Alps and elsewhere over the past decade: In 2017, a rock-ice avalanche at Pizzo Cengalo in eastern Switzerland caused severe downstream damage, destroying parts of the village of Bondo and claiming eight lives13<\/a>,14<\/a>; in 2024 also in eastern Switzerland, a rock-ice avalanche followed the collapse of Piz Scerscen15<\/a>; in 2022, a glacier collapse in the Russian Caucasus buried the village of Nizhniy Karmadon and dammed local river systems, with the loss of 125 lives16<\/a>; in 2018, the Sedongpu glacier detachment in southeast Tibet dammed the Yarlung Tsangpo river17<\/a>.<\/p>\n

Glacier collapses were common on south-facing slopes in the Northern Hemisphere and at lower elevations under pre-industrial climate conditions8<\/a>, but global warming is shifting the locus of these events to aspects and altitudes that were previously less prone10<\/a>, such as the lower elevation, north facing Birch glacier in the L\u00f6tschen valley1<\/a>. The most recent evacuation of the village of Brienz in the eastern Swiss Alps in June 2025 and growing concerns of the municipality of Kandersteg in the Bernese Alps further emphasise the vulnerability of closely intertwined natural and societal systems in mountainous regions. It is therefore imperative to reassess the safety of existing and planned settlements, agricultural zones, and infrastructure in alpine environments worldwide in light of the expanding regions affected by climate change.<\/p>\n

The Blatten disaster will be preserved in Switzerland\u2019s collective memory as one of the largest and most devastating rock-ice avalanches in modern history. The event emphasises the urgent need to improve research-based policy guidance for detecting, preventing, and managing multi-hazard cascades in steep terrain, including avalanches, debris flows18<\/a>, and glacial lake outburst floods19<\/a>. This task requires routine acquisition and interpretation of high-resolution in situ and remote sensing data and the integration of hazard assessments with robust early warning systems to enhance resilience and reduce risk in populated and remote mountain regions. While continuous monitoring and effective risk management in the L\u00f6tschen valley prevented mass casualties, other regions of the world lack the means and expertise to establish such early warning systems.<\/p>\n

Reporting summary<\/p>\n

Further information on research design is available in the\u00a0Nature Portfolio Reporting Summary<\/a> linked to this article.<\/p>\n","protected":false},"excerpt":{"rendered":"The complex, interacting and multi-seasonal rock mechanical, glacial and hydrological processes that led to the Birch glacier\u2019s detachment…\n","protected":false},"author":2,"featured_media":23415,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[50,14955,5943,457,584,14956],"class_list":{"0":"post-23414","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-alps","8":"tag-alps","9":"tag-climate-change-impacts","10":"tag-earth-sciences","11":"tag-environment","12":"tag-general","13":"tag-natural-hazards"},"share_on_mastodon":{"url":"","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/posts\/23414","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/comments?post=23414"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/posts\/23414\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/media\/23415"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/media?parent=23414"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/categories?post=23414"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ch\/wp-json\/wp\/v2\/tags?post=23414"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}