Abstract/Description
This study examines the recent evolution of two ice caves of the northern French Alps : Cave à Glace d’Anterne (2242 m a.s.l., Fiz massif, Haute-Savoie), possibly located in permafrost area, and Grande Glacière du Parmelan (1605 m, Bornes massif, Haute-Savoie), that preserves an important perennial ice mass outside typical cryospheric zones. We try to understand their recent thermal and glaciological dynamics, as well as their value as a paleo-environmental archive.
At Grande Glacière du Parmelan for example, we combined several complementary methods. Terrestrial laser scanning (TLS) provided a detailed 3D model of the cave and, using thickness drillings, an estimate of the ice volume (c. 8,800 m3). Temperature and ice-thickness monitoring over the year 2023-2024 revealed a mean annual temperature close to 0 °C. Despite some winter ice formation, measurements showed progressive thinning by several centimetres to decimetres over the year. Radiocarbon dating of organic fragments trapped in the ice indicated ages between c. 120 and c. 1260 years BP, confirming the cave’s ability to preserve old ice and record environmental conditions over centuries. The cave is part of a karstic drainage system, which allows air and water exchange; this makes it a dynamic ice cave. Such hydrological and thermal connections, however, also enhance vulnerability to climate warming and external disturbances. Historically, the cave’s ice was exploited in the 19th century for refrigeration, and today it serves as a site for recreation and tourism, raising management and conservation concerns.