The threat from rock slope failures to ski resorts

Google Earth image showing the landslide upslope from the Les Menuires ski resort in France. A very interesting new paper (Blondeau and Gunnell 2026) in The Journal of Environmental Management seeks to understand the evolving patterns of landslide risk in ski resorts in northern France. Skiing is a very popular activity in many high mountain areas, perhaps most notably the European Alps. Thus, skiing places large numbers of people at high elevations. But these are also areas that are prone to rock slope failures, the frequency of which is undoubtedly increasing in response to climate change. Thus, there is an interesting question as to the level of increased risk that is developing as a result of the juxtaposition of these two processes. There is a very interesting new paper (Blondeau and Gunnell 2026) in The Journal of Environmental Management that seeks to understand these issues within the northern French Alps. This is an area with 116 ski areas. And a bonus is that the paper is both open access and published under a CC license. Blondeau and Gunnell (2026) focuses on areas of deep-seated gravitational slope deformation (DsGSD), which they term rock-slope deformation (RSD). These area areas of large rock mass failure that (in the words of the authors) “creep slowly for centuries or millennia but can eventually fail catastrophically, thereby presenting major threats to society”. The paper presents maps of areas of RSD in relation to the 116 ski resorts. They have identified 888 RSD areas across the northern French Alps. Of these, 206 intersect with ski resorts, meaning that 69 of the skiing areas are affected. The Google Earth image below shows one such area highlighted in the paper – this is the Les Menuires resort – the landslide upslope of the town is quite clear:- Google Earth image showing the landslide upslope from the Les Menuires ski resort in France. Blondeau and Gunnell (2026) have calculated that 86% of Les Menuires ski area is affected by RSDs. Of course the key question is which is these sites has the potential to transition into a dangerous failure, which could range from rockfalls to a rock avalanche. The authors suggest that InSAR analysis could be used to determine those areas most at risk of large-scale failures – their analysis suggests that 43 of the 69 sites noted above have ongoing deformation detected via this method. But they also note that effective hazard management would involve a range of techniques. This is a very interesting and thought-provoking paper, highlighting the ways in which changing hazard and increases in vulnerable populations combine to drive increased risk. It will be interesting to see whether a more systematic approach to managing the threat is the result. Reference Blondeau, S. and Gunnell, Y. 2026. Sliding on landslides: A survey and assessment of environmental threats to ski areas situated on large failing rock masses in the French Alps.Journal of Environmental Management, 419, 131284, https://doi.org/10.1016/j.jenvman.2026.131284. Text © 2026. The authors. CC BY-NC-ND 3.0Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.