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Bedrock rivers work to incise terrain down to base level. Their geomorphic work is accomplished by the transfer of momentum from flow to particles that strike the bed and walls, or, more effectively, to pluck fracture-bound blocks from the boundary. Through this latter process, bedrock fractures can control bedrock river morphology at the reach scale by dictating local vertical and lateral incision rates. At the watershed scale, regional structure patterns partly control channel alignment by providing fractured rock along discontinuities where incision rates are enhanced. We investigated the structural controls on the alignment of bedrock canyons along the Fraser River, British Columbia, Canada, and controls on the reach-scale morphology of one of its major canyons. We used topographic data and optical imagery derived from multibeam echo-soundings, drones, airborne LiDAR, and satellite sensors. We produced a digital elevation model that includes bedrock walls both above and below the water surface. Our analysis of these data shows that the canyon geometry of the Fraser River is controlled by a combination of large landslides and faults and reveals that epigenetic gorges created by landslides have distinct geometries and morphologies from those canyons associated with faults. Kinematic rock slope analysis of the walls of one major canyon reveals that reach-scale geometry is partly controlled by the orientation of the major joint sets. Vertical and horizontal joints appear to dictate the style of rock erosion and the propensity for abrasion, undercutting, and plucking, and through this control the spatial distribution of constrictions and pools.

The cryosphere in mountain regions is rapidly declining, a trend that is expected to accelerate over the next several decades due to anthropogenic climate change. A cascade of effects will result, extending from mountains to lowlands with associated impacts on human livelihood, economy, and ecosystems. With rising air temperatures and increased radiative forcing, glaciers will become smaller and, in some cases, disappear, the area of frozen ground will diminish, the ratio of snow to rainfall will decrease, and the timing and magnitude of both maximum and minimum streamflow will change. These changes will affect erosion rates, sediment, and nutrient flux, and the biogeochemistry of rivers and proglacial lakes, all of which influence water quality, aquatic habitat, and biotic communities. Changes in the length of the growing season will allow low-elevation plants and animals to expand their ranges upward. Slope failures due to thawing alpine permafrost, and outburst floods from glacier- and moraine-dammed lakes will threaten downstream populations. Societies even well beyond the mountains depend on meltwater from glaciers and snow for drinking water supplies, irrigation, mining, hydropower, agriculture, and recreation. Here, we review and, where possible, quantify the impacts of anticipated climate change on the alpine cryosphere, hydrosphere, and biosphere, and consider the implications for adaptation to a future of mountains without permanent snow and ice., Earth's Future, 5 (5), ISSN:2328-4277

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The analysis of glacial and periglacial morphodynamics and the study of past climate changes are important tasks for scientific and management purposes within recently deglaciated areas. Climate changes and related effects occurring in the last decades cause uncertainties on the survival of glaciers and affect stability of mountains. A systematic study of natural hazards related to glacial and periglacial morphodynamics of the Western Alps in Italy and the Coast Mountain and the Cordillera in Canada started only in the early 1990s. Since then, several instability phenomena of these glacial and periglacial environments have been analyzed, as well as their relationship with the climatic and environmental changes taking place since the end of the Little Ice Age. From the beginning of the 2000s, it became clear that environmental changes related to global warming were accelerating so quickly in high elevation and glaciated mountains. Within this perspective, we started an international effort to collect data and compare geomorphic processes occurring in the high mountains of two distant geographic areas, but with similar physiographic characteristics. Aims was to provide scientists and local administrations with the most advanced knowledge and tools to deal with climate-related instability events occurred in glacial and periglacial areas of the Italian Alps and of Western Canada, such as landslides, debris flows, glacial lake outburst floods, ice avalanches. We identified the types of instability mainly conditioned by climate change and discussed hazard scenarios. Methodological approaches used in Italy and Canada for studying the impacts of degrading permafrost and glacier ice loss on mountain environments were compared, and strategies for communication and dissemination of results were addressed. Studies have shown differences and similarities among the two areas, which highlight the effects of regional/local physiography and climate and, at the same time, confirm the global scale of the changes underway.

We combine surface displacements derived from satellite-based Interferometric Synthetic Aperture Radar (InSAR) with geomechanical models to assess geohazards near two pipeline corridors: a pipeline right-of-way in central British Columbia and a slope adjacent to Fels Glacier in Alaska. The geomechanical models are based on published geological data and aerial and ground photographs, and are constrained with InSAR-derived displacements and slope inclinometer data.

In the last twenty years, the interest of scientific community towards Earthquake Environmental Effects (EEEs) has progressively increased especially in the frame of INQUA - International Union for Quaternary Research. In 2007 the ESI 2007 (Environmental Seismic Intensity scale) was published, a new intensity scale based only on EEEs resulting by a revision process taking about 8 years, and promoted by several geologists, seismologists and engineers coordinated by Servizio Geologico d'Italia (now ISPRA). The ESI 2007 scale integrates traditional intensity scales, and allow to define seismic intensity based on the entir e scenario of effects. In 2011 the EEE Catalogue was launched, a web infrastructure realized by ISPRA for data collection of EEEs induced by recent, historical and paleoearthquakes at global level. Cataloguing and classifying EEEs has allowed to compare past seismic events and to identify the most vulnerable areas in term of site effect. Some strong earthquakes occurred in the last years have unfortunately pointed out the primary role played by geological effects in the scenario of damages, confirming that seismic hazard cannot be evaluated only based on vibratory ground motion but also on the knowledge about EEEs. This volume provides the state of knowledge about these topics, with the aim to promote the use of the ESI 2007 intensity scale, that has been translated into ten languages, and the EEE Catalogue, as an helpful tool also for land planning, especially in high seismic hazard areas.

The 1963 Vajont Slide was an unparalleled natural disaster; it produced a displacement wave that overtopped the Vajont Dam and destroyed several villages, with the loss of over 2000 lives. In the aftermath of this catastrophe, numerous researchers have attempted to understand the mechanisms and behaviour of the landslide. This paper presents the results of the first detailed digital photogrammetric survey of the Vajont failure surface. Discontinuity orientations were detected and eight discontinuity sets were characterised. Surface morphology profiles reveal several scales of roughness and folding, from a regional-scale syncline to small-scale roughness, all of which played a significant role in failure behaviour.

The Environmental Seismic Intensity scale (ESI2007) is a new earthquake intensity scale only based on the effects triggered by the earthquake in the natural environment. The coseismic effects considered more diagnostic for intensity evaluation are surface faulting and tectonic uplift/subsidence (primary effects), landslides, ground cracks, liquefactions, displaced boulders, tsunamis and hydrological anomalies (secondary effects). The ESI 2007 scale follows the same basic structure as any other XII degree scale, such as the MCS, MM, MSK and EMS scales.