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Ice aprons are defined as very small ice bodies covering steep rock slopes. They have only been the subject of increased scientific interest for a few years, despite the fact that they are a condition for mountaineering and obvious elements in the high-alpine landscapes. However, very little is known about their distribution, evolution and physical characteristics. In this paper, we review the existing knowledge on ice aprons, which have almost exclusively been investigated in the Mont-Blanc massif, Western Alps. We supplement this review with novel results from recent surveys of ice aprons. We used a wide array of methodologies, from remote sensing (multi-source imagery) to in situ (stakes and thermal monitoring) and laboratory (radiocarbon dating and texture analysis) glaciological investigations. In the Mont-Blanc massif, ice aprons occupy 4.2 km2 within the alpine permafrost zone. Temperature measured at the ice–rock interface is indeed largely negative. Thinness of ice aprons coupled with the cold context implies a quasi-stationary shear regime without basal Sliding. Only ice at the surface can possibly melt in warm periods. After a shrinking period from the end of the Little Ice Age to the mid-to-late-1960s, ice aprons experienced a short period of expansion, followed by an accelerated shrinkage since the beginning of the 21st century. This shrinkage now favours rockfall triggering and poses a serious threat to a glaciological heritage since ice aprons host several-thousand-year-old ice. Finally, we synthesize this information to assess the existing definition of ice aprons, and propose some future research directions.

Mountain permafrost warming resulting from climate change increases gravitational hazards. This interdisciplinary study compares the networks of actors involved in managing such hazards in three regions of the European Alps. Interviews were conducted with 40 people (members of local authorities, mountain professionals, and private citizens) at the foot of Mont Blanc (Chamonix, France), in the Vanoise massif (France), and in the canton of Valais (Switzerland). Data were analysed qualitatively and quantitatively using interaction matrices and network diagrams. Communal authorities played a central role but partnered with many other public and private actors. In Valais, collaboration to protect infrastructure and inhabited areas was centred around communal and cantonal authorities. In Chamonix, the network of actors gave a significant role to mountain professionals. In Vanoise, the network was less dense and less well-defined, although actors had high expectations regarding awareness-raising and prevention. Sources of tension existed in all three networks, particularly between authorities and mountain professionals. To strengthen community resilience, authorities should develop more mechanisms for citizen participation in risk management.

Since the end of the 20th century, each decade has been warmer than the previous one in the European Alps. As a consequence, Alpine rock walls are generally facing high rockfall activity, likely due to permafrost degradation. We use a unique terrestrial laser scanning derived rockfall catalog over 18 years (2005–2022) compared with photographs (1859–2022) to quantify the evolution of the east face of Tour Ronde (3440–3792 m a.s.l.) in the Mont-Blanc massif (western European Alps) that is permafrost-affected. Overall, 210 rockfalls were identified, from 1 to 15 500 m ^3 . Forty-five events were >100 m ^3 while cumulated volume of events

The current paper studies the dynamics and age of the Triangle du Tacul (TDT) ice apron, a massive ice volume lying on a steep high-mountain rock wall in the French side of the Mont-Blanc massif at an altitude close to 3640 m a.s.l. Three 60 cm long ice cores were drilled to bedrock (i.e. the rock wall) in 2018 and 2019 at the TDT ice apron. Texture (microstructure and lattice-preferred orientation, LPO) analyses were performed on one core. The two remaining cores were used for radiocarbon dating of the particulate organic carbon fraction (three samples in total). Microstructure and LPO do not substantially vary with along the axis of the ice core. Throughout the core, irregularly shaped grains, associated with strain-induced grain boundary migration and strong single maximum LPO, were observed. Measurements indicate that at the TDT ice deforms under a low strain-rate simple shear regime, with a shear plane parallel to the surface slope of the ice apron. Dynamic recrystallization stands out as the major mechanism for grain growth. Micro-radiocarbon dating indicates that the TDT ice becomes older with depth perpendicular to the ice surface. We observed ice ages older than 600 year BP and at the base of the lowest 30 cm older than 3000 years.

The glacial and torrential basin of Taconnaz (Mont-Blanc massif, France) dominates the Chamonix valley. It is one of the major paths for snow avalanches in the Alps, often triggered by serac falls from the Taconnaz glacier. On 24 November 2018, the basin’s multi-risk nature was further accentuated by a new type of hazard with a rockfall triggered at c. 2700 m a.s.l. It travelled down over a distance of 1.85 km and stopped 165 m away from the construction site of a micro-hydroelectric power station. We studied the triggering conditions at the permafrost lower limit, the effects of the supra-glacial path on the flow patterns, and the fate of the scar and the deposit on torrential activity. By comparing a pre-event Structure from Motion model with a post-event LiDAR model, we estimated the volume of the scar to be 42,900 m3 (±5%). A numerical model was employed to simulate the rapid runout. It revealed the complexity of the flow, attributed to the sequestration of a part of the deposit in crevasses, the incorporation of a significant volume of ice resulting in a transition from a dry granular flow to a mud-like flow, and the presence of numerous deposit zones. Subsequent monitoring of the area after the event allowed for the documentation of the scar’s evolution, including a landslide, as well as the progressive degradation and evacuation of the deposit by the torrent without producing debris flow. The study of the triggering factors indicated glacial retreat as the probable main cause, assisted by the melting of ice lenses left by the permafrost disappearance. Finally, we present replicable methods for managing risks at the site following the event. This event improves the understanding of cascading processes that increasingly impact Alpine areas in the context of climate change.

This paper investigates the backscatter evolution and surface changes of ice aprons (IAs) by exploiting time series of X- and C-band SAR images from PAZ and Sentinel-1 satellites. IAs are extremely small ice bodies of irregular shape present on steep slopes and complex topographies in all the major high-Alpine environments of the world. Due to their small size and locations in complex topographies, they have been very poorly studied, and very limited information is known about their evolution and responses to climate change. SAR datasets can provide handy information about the seasonal behaviour of IAs since physical changes of IA surfaces modify the backscattering of RaDAR waves. The analysis of the temporal variations of the backscatter coefficient illustrates the effects of increasing temperatures on the surface of the IAs. All IAs considered in the analysis show a strong decrease in backscatter coefficient values in the summer months. The backscattering patterns are also supported by the annual evolution of the coefficient of variation, which is an appropriate indicator to evaluate the heterogeneity of the surface. Higher mean backscatter values in the X-band than in the C-band indicate surface scattering phenomena dominate the IAs. These features could provide key information for classifying IAs using SAR images in future research.

As part of an archaeological research project, we investigate the geomorphology of the cold and arid study area by combining field mapping with use of orthoimages and DEM. To the north of a broad trunk valley floor, gentle slopes continuously vegetated culminate around 3000 m, while to the south steep slopes reaching to 3500 m are deeply incised and covered mainly by regolith. The basin has been intensively glaciated as evidenced by the till covering the gentler slopes, several morainic complexes, kame terraces and roches moutonnées. The present morphodynamics of this permafrost-affected basin is mainly periglacial, with blockfields, solifluction lobes, patterned ground and rock glaciers on gentle slopes to high-elevated flat terrain, and block slopes and rockfall talus on steeper slopes. Large alluvial fans at the outlet of the steep lateral valleys constrain the anastomosing channel of the Kalguty river. Active braided channels in those valleys evidence seasonal high peak discharge.

Deglaciation of high mountain rockwalls alters slope stability as rockwalls become more sensitive to modifications in environmental factors (e.g. seasonal temperature variations). In the past decades, increasing efforts focused on studying deglaciated Alpine rockwalls. Yet, currently deglaciating rockfaces remain unstudied. Here, we quantify surface area variations of massive ice bodies lying on high mountain rockwalls (ice aprons) in the French sector of the Mont Blanc massif between the end of the Little Ice Age (LIA) and 2018. Surface area estimates are computed from terrestrial and aerial oblique photographs via photogrammetry. This technique allows using photographs taken without scientific intent, and to tap into diverse historical or recent photographic catalogs. We derive an ice apron surface area model from precipitation records and the positive degree-days. The studied ice aprons shrank from 1854 to the 1950s, before expanding until the end of the 1990s. The beginning of the 21st century shows a decrease in surface area, leading to the complete melt of one of the studied ice aprons in 2017. Observed variations correlate with modeled surface area, suggesting strong sensitivity of ice aprons to changes in climatic variables. By studying site-specific correlations, we explore the importance of local drivers over the balance of ice aprons.

Ice aprons are poorly studied and not well-defined thin ice bodies adhering to high altitude steep rock faces, but are present in most Alpine-type high mountain environments worldwide. This study aims to precisely define ice aprons based on a detailed analysis of their topographical characteristics in the Mont Blanc massif (western European Alps). For this, we accurately identified and precisely mapped 423 ice aprons using a combination of high-resolution optical satellite images from 2019. To better understand their relationship with other types of glaciers, especially the steep slope glaciers and other surface ice bodies, we built a detailed inventory at the scale of the massif that incorporates nine different types of perennial surface ice bodies. In addition, an analysis using different topographic factors helped us to better understand the preferred locations of the ice aprons. We show that they predominantly occur on west-oriented steep and topographically rugged rock slopes above the local Equilibrium Line Altitude (~3200 m a.s.l.), with concave profile curvatures around them that facilitate snow accumulation. They are also found in areas underlain by permafrost. The extensive inventory also helped us to identify different types of ice aprons based on their relationships with glaciers/ice bodies. The analysis shows that ice aprons existing at the headwall of large glaciers above a bergschrund are the most dominant ice apron type in the study area, with ~82% of the total.

Chronological estimation of rock art figures based on stylistical criterias, especially when a very ancient age is suspected, is never easy to argue. This is the case of animal representations of Southern Altai and North-Western Mongolia, presenting characteristics compatible with the canon of Palaeolithic Art. In the absence of direct dating of these petroglyphs, different approaches have been undertaken, dealing at the same time with technic (lithic tools), substrate, topographical location and past accessibility (rocks released from glaciers before the end of the Upper Palaeolithic) in order to reduce the main objections that may be opposed to graphic comparisons. This interdisciplinary approach, involving microscopy, traceo-technology, 2D and 3D imagery, geomorphology and cosmogenic dating, has been done in the framework of the franco-russian Associated International Laboratory (LIA) ARTEMIR.

In high alpine environments, glacial shrinkage and permafrost warming due to climate change have significant consequences on mountaineering routes. Few research projects have studied the relationship between climate change and mountaineering; this study attempts to characterize and explain the evolution over the past 40 years of the routes described in The Mont Blanc Massif: The 100 Finest Routes, Gaston Rébuffat’s emblematic guidebook, published in 1973.The main elements studied were the geomorphic and cryospheric changes at work and their impacts on the itinerary’s climbing parameters, determining the manner and possibility for an itinerary to be climbed. Thirty-one interviews, and comparison with other guidebooks, led to the identification of 25 geomorphic and cryospheric changes related to climate change that are affecting mountaineering itineraries. On average, an itinerary has been affected by nine changes. Among the 95 itineraries studied, 93 have been affected by the effects of climate change – 26 of them have been greatly affected; and three no longer exist. Moreover, periods during which these itineraries can be climbed in good conditions in summer have tended to become less predictable and periods of optimal conditions have shifted toward spring and fall, because the itineraries have become more dangerous and technically more challenging.

Landslides triggered by shrinking glaciers are an expected outcome of global climate change and they pose a significant threat to inhabitants and infrastructure in mountain valleys. In this study we document the rock slope movement that has affected the Pilatte hut (2,572 m a.s.l.) in the Écrins range (French alps) since the 1980s. We reconstructed the geometry of the unstable rock mass using Terrestrial Laser Scanning and quantified the unstable volume (~400,000 m3). Field observations and annual crack surveys have been used to identify the dynamics of past movements. These movements initiated in the late 1980s and have accelerated since 2000. The current trend seems to be toward a relative stabilization. Reconstruction of the glacier surface using past images taken since 1960 and “Structure from Motion” photogrammetry showed that the glacier probably applied stresses to the rock slope during its short-lived advance during the 1980s, followed by debuttressing caused by rapid surface lowering until the present day. The relationship between observed crack propagation and glacier surface change suggests that the rock slope instability is a paraglacial response to glacier surface changes, and highlights that such responses can occur within a decade of glacier change.

The aim of this article is to present a methodology for encouraging local stakeholders to cooperate on the prevention of an emerging risk. It concerns the degradation of mountain permafrost, which, with global warming, generates natural hazards (landslides, collapses, torrential lava) that create vulnerability for mountain professionals, public protection authorities and citizens living in the valleys. This methodology involves two steps. Firstly, an individual interview, based on intermediate objects (maps and real-life cases), leads the person into a reflective activity. This step prepares the way for the second step: the democratic workshop, where stakeholders discuss and exchange their needs on a regional level. The construction of this methodology, based on an interdisciplinary approach between ergonomics and geosciences, enables us to better grasp the stakes involved in the risk of permafrost degradation for those working in the field, in relation to their human activity and its evolution. It leads to a better understanding of phenomena in a given area, and to the development of preventive actions and social demand.

L’alpinisme est l’une des pratiques sportives les plus affectées par la crise climatique actuelle en raison de l’évolution des milieux physiques de haute montagne. Certains itinéraires ont disparu, d’autres ne sont plus fréquentables en été (exposition aux aléas, difficultés techniques, etc.). Des recherches ont déjà été réalisées sur les impacts du changement climatique sur la pratique de l’alpinisme et l’adaptation des pratiquants. Le massif du Mont-Blanc et les Alpes valaisannes ont ainsi servi de territoires d’étude pour comprendre l’évolution des itinéraires d’alpinisme au cours des dernières décennies. Une cartographie des processus géomorphologiques et glaciologiques affectant des itinéraires d’alpinisme a été réalisée pour le Valais et la présente étude vise à appliquer cette méthode au massif des Écrins, qui restait non étudié malgré son caractère emblématique. Le célèbre topoguide Le massif des Écrins — Les 100 plus belles courses et randonnées (1974) a été utilisé comme base de travail, et 70 itinéraires ont été sélectionnés selon leur fréquentation et leur notoriété. L’ensemble des processus qui les affectent ont été cartographiés sous SIG et une analyse statistique a été réalisée pour mieux comprendre l’évolution des itinéraires, en parallèle d’entretiens semi-directifs auprès d’expert·es et praticien•nes de terrain. Un nouveau processus — la fonte prématurée en saison estivale des couvertures glacio-nivales — a été identifié. Comme pour le massif du Mont-Blanc et le Valais, un itinéraire est en moyenne affecté par neuf processus, et près de 25 % des itinéraires ne sont plus fréquentables l’été. Les itinéraires en neige et mixtes et d’une difficulté supérieure à D (Difficile) sont les plus impactés. La méthode de cartographie a ainsi été appliquée avec succès au massif des Écrins, permettant de compléter les connaissances sur l’évolution récente des itinéraires d’alpinisme.

Mountaineering is one of the most affected sports activities due to the current climate crisis and the resulting changes in the physical environment of the high mountain areas. Some routes have disappeared while others are no longer accessible in summer (hazards, technical difficulties, etc.). Research has already been conducted on the impact of climate change on mountaineering and on adaptation. The Mont-Blanc massif and the Valais Alps have been used as study areas to understand the evolution of mountaineering routes over recent decades. A mapping of the geomorphological and glaciological processes affecting mountaineering routes has been conducted for the Valais. This study aims to apply this method to Écrins massif (French Alps), which had so far remained unstudied despite its emblematic character. The famous topo-guide "Le massif des Écrins - Les 100 plus belles courses et randonnées" (1974) was used as a basis for the study with 70 routes being selected according to their notoriety and visitor numbers. All the processes affecting the routes were mapped using GIS, and a statistical analysis was carried out to gain a better understanding of the evolution of the routes, together with semi-directive interviews with experts and practitioners. A new process – the early summer melting of ice and snow cover – was identified. As is the case in the Mont-Blanc massif and the Valais, a route is affected by 9 processes on average, and almost 25% of the routes can no longer be climbed in summer. The mapping method has been successfully applied to Écrins massif, providing new knowledge of the recent evolution of mountaineering routes in the Alps.

Glacial shrinkage and the gravitational processes associated with it, which are characteristic of global warming effects in high mountain environments, are affecting mountaineering routes more and more, including access routes to high altitude refuges. These changes have almost never been studied. Also, this research seeks to identify and explain the evolution of access trails to five refuges, located in the Mer de Glace basin (Mont Blanc massif), over more than a century. This glacier is the largest in France (L = 11.5 km, SA = 30 km²) is a major Alpine tourist attraction since 1741 and is the birthplace of mountaineering. This work is based on a three-step methodology: 1) collection and analysis of maps, climbing guidebooks and photographs, 2) semi-structured interviews and 3) analysis of high-resolution digital terrain models obtained through terrestrial laser scanning.While there was not a significant evolution during most of the 20th century, glacier thickness loss and the associated erosion of lateral moraines have resulted in numerous modifications made to the access trails since the 1990s. Despite these adaptations, the danger they pose continues to rise, and the necessity to equip them is ever more important (633 m. of ladders at present), which raises doubts about the future accessibility of such high mountain refuges.

Alpine mountains are affected by significant geomorphological processes whose evolution is partly conditioned by permafrost warming: rockfalls of various volumes, destabilisation of rock glaciers, and cryokarst. These phenomena, because of their intensity, may generate risks for territories. This paper provides a synthesis of the knowledge about the current status of the mountain permafrost in the French Alps and its recent evolution. This state-of-the-art overview is based on research conducted over the past 10 years and the measurements collected within PermaFRANCE, the French network for long-term observation of the mountain permafrost. The analysis of the available data shows that for a rock wall located at 3800 m asl., the temperature is between -4.5 and -1.5°C at a depth of 10 m, according to the aspect, whereas it is close to the melting point in surficial deposits at 2800 m asl. on a northern slope. Since the beginning of these measurements at depth in 2010, a trend of increasing temperature has been discernible, as found in other alpine boreholes. As clearly shown by the surface measurements conducted since 2003, the thermal regime is influenced by snow, particularly in surficial deposits and to a much lesser extent in rock walls. This inter-annual variability is combined with longer-term trends, which probably induce the observed changes in geomorphological dynamics associated with alpine permafrost: an increased frequency of gravitational processes such as rockfalls and fluctuation in rock glacier velocities. The possible increase in extreme events, such as rock avalanches or the destabilisation of rock glaciers, in the coming decades could create new or increased risks, to which territories must thus adapt.

Alpine mountains are affected by significant geomorphological processes whose evolution is partly conditioned by permafrost warming: rockfalls of various volumes, destabilisation of rock glaciers, and cryokarst. These phenomena, because of their intensity, may generate risks for territories. This paper provides a synthesis of the knowledge about the current status of the mountain permafrost in the French Alps and its recent evolution. This state-of-the-art overview is based on research conducted over the past 10 years and the measurements collected within PermaFRANCE, the French network for long-term observation of the mountain permafrost. The analysis of the available data shows that for a rock wall located at 3800 m asl., the temperature is between -4.5 and -1.5°C at a depth of 10 m, according to the aspect, whereas it is close to the melting point in surficial deposits at 2800 m asl. on a northern slope. Since the beginning of these measurements at depth in 2010, a trend of increasing temperature has been discernible, as found in other alpine boreholes. As clearly shown by the surface measurements conducted since 2003, the thermal regime is influenced by snow, particularly in surficial deposits and to a much lesser extent in rock walls. This inter-annual variability is combined with longer-term trends, which probably induce the observed changes in geomorphological dynamics associated with alpine permafrost: an increased frequency of gravitational processes such as rockfalls and fluctuation in rock glacier velocities. The possible increase in extreme events, such as rock avalanches or the destabilisation of rock glaciers, in the coming decades could create new or increased risks, to which territories must thus adapt.

Under the effects of climate change, Alpine mountainous regions are undergoing fast and well-perceptible evolutions, which are attracting the growing attention of people, scientists and managers. To cope better with the hazards and vulnerabilities specific to these territories, the current national and European public policies in the Alpine countries now prescribe adapting natural hazard prevention to climate change. This paper provides a review of recent advances in knowledge on the perceived, measured and projected changes in i) climate patterns, ii) the cryosphere, hydrosystems and geomorphological dynamics on Alpine slopes, and iii) natural hazard evolution and induced risks at the scale of the French Alps. We give a brief overview of new results achieved by research, cooperation and capitalisation projects in these thematic fields during the programme period 2007-2013, which are available on databases, thematic knowledge platforms and observatories developed by different scientific and technical operators in the larger framework of the European Alpine arc. We illustrate this renewed synthesis by published examples of hydro-gravitational hazard activity chronicles, along with climate patterns identified as “predictors”.

Under the effects of climate change, Alpine mountainous regions are undergoing fast and well-perceptible evolutions, which are attracting the growing attention of people, scientists and managers. To cope better with the hazards and vulnerabilities specific to these territories, the current national and European public policies in the Alpine countries now prescribe adapting natural hazard prevention to climate change. This paper provides a review of recent advances in knowledge on the perceived, measured and projected changes in i) climate patterns, ii) the cryosphere, hydrosystems and geomorphological dynamics on Alpine slopes, and iii) natural hazard evolution and induced risks at the scale of the French Alps. We give a brief overview of new results achieved by research, cooperation and capitalisation projects in these thematic fields during the programme period 2007-2013, which are available on databases, thematic knowledge platforms and observatories developed by different scientific and technical operators in the larger framework of the European Alpine arc. We illustrate this renewed synthesis by published examples of hydro-gravitational hazard activity chronicles, along with climate patterns identified as “predictors”.

Due to ongoing global warming, high alpine environments are affected by significant changes, such as glacial retreat and permafrost warming, which can trigger mass movements in rock slopes or superficial deposits. These processes generate a risk of direct destabilisation for high mountain infrastructures (huts, cable cars, etc.). To help prevent such risks, an inventory of all the high mountain infrastructures in the French Alps was carried out using a Geographic Information System. This combined several data layers, including the Alpine Permafrost Index Map and glacier inventories since the end of the Little Ice Age. 1,769 infrastructures were identified in areas probably characterised by permafrost and/or possibly affected by glacier shrinkage. An index of destabilisation risk was constructed to identify and rank infrastructures at risk. This theoretical risk index includes a characterisation of hazards and a diagnosis of vulnerability. 10 % of the infrastructures were characterised by a high risk of destabilisation.

Due to ongoing global warming, high alpine environments are affected by significant changes, such as glacial retreat and permafrost warming, which can trigger mass movements in rock slopes or superficial deposits. These processes generate a risk of direct destabilisation for high mountain infrastructures (huts, cable cars, etc.). To help prevent such risks, an inventory of all the high mountain infrastructures in the French Alps was carried out using a Geographic Information System. This combined several data layers, including the Alpine Permafrost Index Map and glacier inventories since the end of the Little Ice Age. 1,769 infrastructures were identified in areas probably characterised by permafrost and/or possibly affected by glacier shrinkage. An index of destabilisation risk was constructed to identify and rank infrastructures at risk. This theoretical risk index includes a characterisation of hazards and a diagnosis of vulnerability. 10 % of the infrastructures were characterised by a high risk of destabilisation.

Gletscher sind seit fast zwei Jahrhunderten beliebte Touristenattraktionen. Doch der aktuelle Klimawandel stellt sogar die Existenz von Gletschern in Frage. In diesem Zusammenhang soll in diesem Artikel die Frage gestellt werden, welche Formen des Tourismus heute in allen alpinen Gletschertourismusorten zu erkennen sind. Eine Bestandsaufnahme im Maßstab des Alpenbogens zeigt, dass verschiedene touristische Praktiken (Betrachten, Besuch von Eishöhlen, Freizeitaktivitäten, Umweltbildung und Luxus) nebeneinander bestehen. Die Analyse der Funktionsweise der verschiedenen Standorte zeigt, dass diese Praktiken mit den verschiedenen in der Literatur beschriebenen Formen des Tourismus in Verbindung gebracht werden können: moderner, postmoderner und hypermoderner Tourismus. Die Koexistenz dieser Formen auf der Ebene der Gletscherstandorte offenbart sechs mögliche Kombinationen, d.h. sechs Standorttypen: betrachtend, erlebnisorientiert, erholsam, interpretativ, hochwertig und unverwechselbar. Ihre räumliche Analyse zeigt auch, dass die Orte mit der höchsten Qualität (Premium und distinktiv) sich hauptsächlich um die Höhepunkte des Alpentourismus (Chamonix, Zermatt und Grindelwald) befinden, während die anderen gleichmäßiger verteilt sind. Diese Ergebnisse stellen die Frage nach den Entwicklungsverläufen der Standorte und der Rolle des Klimawandels, mögliche Objekte zukünftiger Forschung.

Glaciers have been popular tourist attractions for almost two centuries. However, current climate change is now posing a new threat. In this context, this paper aims to question the tourism forms which are currently identifiable within Alpine glacier tourism sites. An inventory carried out on an Alpine scale shows that different tourist practices (contemplation, visit of ice caves, recreational activities, environmental education, and luxury) can coexist. The analysis of the way various sites function demonstrates that these practices can be related to the different forms of tourism that exist in the scientific literature: modern, post-modern and hyper-modern tourism. The coexistence of these forms of tourism at glacier sites reveals six possible combinations, i.e. six types of sites: contemplative, experiential, recreational, interpretative, premium and distinctive. Spatial analysis also shows that the premium and distinctive sites are mainly located around the major Alpine tourist destinations (Chamonix, Zermatt and Grindelwald), while the others are more homogeneously distributed. These results raise questions about the way in which these sites was and will develop and the role climate change plays, both of which constitute potential research topics for the future.

Glaciers have been popular tourist attractions for almost two centuries. However, current climate change is now posing a new threat. In this context, this paper aims to question the tourism forms which are currently identifiable within Alpine glacier tourism sites. An inventory carried out on an Alpine scale shows that different tourist practices (contemplation, visit of ice caves, recreational activities, environmental education, and luxury) can coexist. The analysis of the way various sites function demonstrates that these practices can be related to the different forms of tourism that exist in the scientific literature: modern, post-modern and hyper-modern tourism. The coexistence of these forms of tourism at glacier sites reveals six possible combinations, i.e. six types of sites: contemplative, experiential, recreational, interpretative, premium and distinctive. Spatial analysis also shows that the premium and distinctive sites are mainly located around the major Alpine tourist destinations (Chamonix, Zermatt and Grindelwald), while the others are more homogeneously distributed. These results raise questions about the way in which these sites was and will develop and the role climate change plays, both of which constitute potential research topics for the future.

Climate change is a global challenge that also for glacier tourism. In the European Alps, glacial volume has decreased to one half since the end of the Little Ice Age. To confront with this evolution, local stakeholders are slowing adapting diversification on their tourism products and services. One of these adaptations concerns highlighting the scientific value of the glacier landscapes. Several Glacier Interpretation Centres (GIC) have been developed with the dual aim of spreading scientific knowledge and promoting glacier tourism destinations. Based on a qualitative approach and built in a historical and geographical perspective, this article aims to examine the territorial dynamics and the interaction of stakeholders which led to the creation of three of these centres: the Espace Glacialis (Champagny-le-Haut, France), the Glaciorium (Chamonix, France) and the World Nature Forum (Naters, Switzerland). Through a comparative analysis of these three GICs, the objective is to understand how the valorization of scientific knowledge contributes to the diversification of tourism in mountain areas. Although glacier tourism destinations are profoundly affected by climate change, the results show that local authorities have a strong will to continue to promote their glacier heritages through the creation and management of GICs, these centres undeniably contribute to the diversification of the tourism market and to the dynamisation of the tourism activity in their territories by relying on scientific knowledge and its mediation.

The evolution of the high Alpine mountain environment, especially the cryosphere that faces climate change, deeply modifies the human activities that take place there. The mountaineering routes are directly impacted and they sometimes become inaccessible. In order to recover a good balance, adaptation is necessary. Mountain guides are among the most dependent professionals on the field on which they practice. As a result, they are probably the most impacted professionals but, at the same time, they are also those who can produce a lot of adaptation strategies. The aim of this paper is therefore to identify how mountain guides from Chamonix and Courmayeur are impacted and the different adaptation strategies they developed to face climate change. By this cross-border study, using quantitative and qualitative methods, this paper is also showing that the adaptation strategies are controlled by the territory dynamics.

The evolution of the high Alpine mountain environment, especially the cryosphere that faces climate change, deeply modifies the human activities that take place there. The mountaineering routes are directly impacted and they sometimes become inaccessible. In order to recover a good balance, adaptation is necessary. Mountain guides are among the most dependent professionals on the field on which they practice. As a result, they are probably some of the most impacted professionals but, at the same time, they are also those who can create a lot of adaptation strategies. The aim of this paper is therefore to identify how mountain guides from Chamonix and Courmayeur are impacted and the different adaptation strategies they developed to face climate change. By this cross-border study, using quantitative and qualitative methods, this paper is also showing that the adaptation strategies are controlled by the territory dynamics.

Climate change is a global challenge that also for glacier tourism. In the European Alps, glacial volume has decreased to one half since the end of the Little Ice Age. To confront with this evolution, local stakeholders are slowing adapting diversification on their tourism products and services. One of these adaptations concerns highlighting the scientific value of the glacier landscapes. Several Glacier Interpretation Centres (GIC) have been developed with the dual aim of spreading scientific knowledge and promoting glacier tourism destinations. Based on a qualitative approach and built in a historical and geographical perspective, this article aims to examine the territorial dynamics and the interaction of stakeholders which led to the creation of three of these centres: the Espace Glacialis (Champagny-le-Haut, France), the Glaciorium (Chamonix, France) and the World Nature Forum (Naters, Switzerland). Through a comparative analysis of these three GICs, the objective is to understand how the valorization of scientific knowledge contributes to the diversification of tourism in mountain areas. Although glacier tourism destinations are profoundly affected by climate change, the results show that local authorities have a strong will to continue to promote their glacier heritages through the creation and management of GICs, these centres undeniably contribute to the diversification of the tourism market and to the dynamisation of the tourism activity in their territories by relying on scientific knowledge and its mediation.

Glacial shrinkage and the gravitational processes associated with it, which are characteristic of global warming effects in high mountain environments, are affecting mountaineering routes more and more, including access routes to high altitude refuges. These changes have almost never been studied. Also, this research seeks to identify and explain the evolution of access trails to five refuges, located in the Mer de Glace basin (Mont Blanc massif), over more than a century. This glacier is the largest in France (L = 11.5 km, SA = 30 km²) is a major Alpine tourist attraction since 1741 and is the birthplace of mountaineering. This work is based on a three-step methodology: 1) collection and analysis of maps, climbing guidebooks and photographs, 2) semi-structured interviews and 3) analysis of high-resolution digital terrain models obtained through terrestrial laser scanning.While there was not a significant evolution during most of the 20th century, glacier thickness loss and the associated erosion of lateral moraines have resulted in numerous modifications made to the access trails since the 1990s. Despite these adaptations, the danger they pose continues to rise, and the necessity to equip them is ever more important (633 m. of ladders at present), which raises doubts about the future accessibility of such high mountain refuges.

L’augmentation de la fréquence des écroulements rocheux (V > 100 m3), d’abord observée dans les Alpes européennes depuis les années 2000, a impulsé des études sur les parois de haute altitude et le permafrost de paroi. Le massif du Mont-Blanc (MMB) est progressivement devenu un terrain d’étude pilote grâce aux nombreuses données et connaissances acquises au travers de divers projets de recherche. L’analyse statistique de la distribution des écroulements (> 1300 événements recensés entre 2007 et 2021) met en évidence leur lien avec la distribution du permafrost ainsi qu’avec l’augmentation de la température de l’air. Cette analyse ouvre des perspectives prometteuses en termes de développement d’outils de prévision pour aider les pratiquant·es de la haute montagne et les acteurs·rices dans leurs stratégies d’atténuation des risques. Néanmoins, la compréhension des mécanismes de déstabilisation des parois rocheuses se heurte à la diversité des processus thermo-hydro-mécaniques potentiellement impliqués. Pour améliorer cette compréhension, les recherches actuellement menées dans le MMB se concentrent sur les processus d’infiltration et de circulation de l’eau dans les parois à permafrost en combinant des approches de modélisation numérique avancées avec des études de terrain ad hoc. Le couplage de modèles thermiques et hydrogéologiques, et leur combinaison avec des méthodes géoélectriques pourraient permettre d’évaluer la distribution et la quantité d’eau ou de glace interstitielle, une information cruciale pour les applications géotechniques. Parallèlement, la synthèse des données et connaissances acquises dans des approches intégrées des changements de paysage et des risques liés à la dégradation du permafrost, au recul des glaciers, à la formation potentielle de lacs et à la déstabilisation des parois rocheuses, apparaît comme une base essentielle pour les projets d’aménagement du territoire. Enfin, les échanges thermiques et hydrologiques entre les parois à permafrost et les appareils nivo-glaciaires qui y sont nichés (tabliers de glace et glaciers suspendus) sont une autre perspective de recherche à explorer, avec des implications pluridisciplinaires.

Mountaineering is a sport highly dependent on the conditions of the physical environments in which it takes place. As a result, mountaineers have to deal with major glacial and periglacial hazards, such as those affecting the two main routes used to climb Mont Blanc (4808 m a.s.l.; Western European Alps): rockfalls in the Grand Couloir du Goûter on the Voie Royale and serac falls on the NNW slope of Mont Blanc du Tacul on the Trois Monts route. Hazards in these two sectors and the number of climbers were measured using a multi-sensor system and automatic photographic acquisition, respectively. On the first site, which has a very high accident rate with an average of 3.7 deaths per year, 17,768 passages were recorded during the summer of 2019 and 2,648 seismic signals were classified as rockfalls affecting the Grand Couloir. The average risk of death associated with these rockfalls, the frequency of which depends on temperatures and the presence of liquid water in the ground, is estimated at 1.7 × 10-4. At Tacul, where an average of 0.6 deaths occur each year, 6,770 passages were recorded during the summer of 2017, as well as 31 serac falls unrelated to temperatures. The risk of death is 8.3 × 10-5. The risk is also quantified for each track made on the glacier. The results obtained makes it possible to specify the risks experienced by climbers and to promote risk reduction strategies.

L’alpinisme est une pratique sportive qui dépend fortement des conditions des milieux physiques dans lesquels elle se développe. Les alpinistes doivent ainsi faire face à des aléas glaciaires et périglaciaires importants, tels que ceux qui affectent les deux principaux itinéraires d’ascension du mont Blanc (4808 m ; Alpes européennes occidentales) : les chutes de pierres dans le Grand Couloir de l’aiguille du Goûter sur la Voie Royale et les chutes de séracs sur le versant NNO du mont Blanc du Tacul sur l’itinéraire des Trois Monts. Les aléas dans ces deux secteurs ainsi que la fréquentation ont été mesurés grâce à un dispositif multicapteurs et à des acquisitions photographiques automatiques, respectivement. Sur le premier site, où l'on déplore une très forte accidentalité avec en moyenne 3,7 décès par an, 17 768 passages ont été comptabilisés au cours de l’été 2019 et 2 648 signaux sismiques ont été classés comme des chutes de pierres ayant affecté le Grand Couloir. Le risque de décès associé à ces chutes de pierres, dont la fréquence est dépendante des températures et de la présence d’eau liquide dans le terrain, serait de 1,7 × 10-4. Au Tacul, où en moyenne 0,6 décès se produit chaque année, 6 770 passages ont été relevés au cours de l’été 2017, ainsi que 31 chutes de séracs sans lien avec les températures. Le risque de décès y est de 8,3 × 10-5. L'aléa est également quantifié pour chacune des traces faites sur le versant glaciaire. Les résultats obtenus permettent de préciser les risques encourus par les alpinistes et de favoriser des stratégies de réduction des risques.

The enhanced rockfall frequency (V > 100 m3) first noticed in the European Alps, has motivated investigations on high mountain rock walls and rock wall permafrost since the 2000s. Mont-Blanc massif (MBM) has become a pilot study area thanks to the wealth of data and knowledge on rockfall and permafrost dynamics acquired through successive research projects. Statistical analysis of rockfall distribution (> 1300 events inventoried between 2007 and 2021) shows that they are related to permafrost distribution and increasing atmospheric temperature, opening promising perspective for developing forecasting tools to support mountain practitioners in their risk mitigation strategy. However, understanding how rock wall destabilizations develop is challenged by the variety of potentially involved thermo-hydro-mechanical processes. To face these challenges, research currently carried out in the MBM focuses on water infiltration and circulation processes in frozen rock walls by combining advanced numerical modelling approaches and ad hoc field surveys. The coupling of models simulating heat and water transport with geoelectrical imaging methods could allow assessment of ground water/ice distributions and contents that is highly relevant for geotechnical purposes. Concurrently, the combination of acquired data and knowledge in integrative approaches of landscape changes and hazards involving permafrost degradation, glacier retreat, possible lake formation and rock wall destabilization appears as an essential basis for land-planning concerns. Finally, thermal and hydrological interactions between rock wall permafrost and ice bodies nestled on rock faces (ice aprons and hanging glaciers) is another direction of research to be pursued with cross-disciplinary implications.