Mylène Jacquemart

• PhD University of Colorado Boulder
• Postdoctoral Researcher at ETH Zurich

Plain Language Summary Climate warming and the resulting retreat of glaciers may destabilize mountain slopes, triggering landslides. For those landslides that enter fjords, the induced tsunamis are a significant hazard to coastal communities. Despite this risk, most periglacial landslides have been detected only after the event. Using satellite dat...

Two large-scale glacier detachments occurred at the peaks of the 2013 and 2015 CE melt seasons, releasing a cumulative 24.4–31.3 × 106 m3 of ice and lithic material from Flat Creek glacier, St. Elias Mountains, Alaska. Both events produced highly mobile and destructive flows with runout distances of more than 11 km. Our results suggest that four ma...

Glacier detachments are a rare phenomenon of glacier instability, whereof only a handful have been documented to date. Common to all known cases are the large detached volumes of many million cubic meters of ice and long runout distances. Recently, two detachments of smaller size were observed in the Petra Pervogo range, north west of the Pamir mou...

The catastrophic failure of the Mud Creek landslide on California’s Big Sur Coast on 20 May 2017 highlighted once again how difficult it is to detect a landslide’s transition from slow moving to catastrophically unstable. Automatic detection methods that rely on InSAR displacement measurements to detect precursory acceleration are available but can...

The detachment of large parts of low-angle mountain glaciers, resulting in massive ice-rock avalanches, have so far been believed to be a unique type of event, made known to the global scientific community first for the 2002 Kolka Glacier detachment, Caucasus Mountains, and then for the 2016 collapses of two glaciers in the Aru range, Tibet. Since...

We present first insights into an englacial temperature module for the Global Glacier Evolution Model (GloGEM), marking an attempt to integrate englacial thermal dynamics into a global glacier model. The module accounts for refreezing in both firn and ice, with the velocity gradient used as a crevassing indicator to parameterize ice permeability. O...

Global warming is leading to ever faster glacier mass loss in every mountain range in the world. At high elevations and high latitudes – where ice temperatures are often still below the melting point – warming is also penetrating into glaciers and leading to measurably warmer ice. This warming can have a strong impact on glacier dynamics and glacie...

Measurements of englacial temperatures have been collected since the earliest years of glaciology, with the first measurements dating back to the mid-19th century. Although temperature is a defining characteristic of any glacier – and is notoriously laborious to collect – no effort had yet been made to gather all existing measurements. In an attemp...

Information about snowpack wetness at high temporal and spatial resolutions is important for timely identification of pre-disposing conditions for avalanche release. However, such information is often available only for specific, instrumented locations. Space-borne techniques such as synthetic aperture radar (SAR) allow us acquiring information ove...

Glaciers worldwide are retreating rapidly due to anthropogenic climate change. One consequence of glacier mass loss is the destabilization of valley walls as the support provided by the glacier changes and eventually vanishes, a process known as ''debuttressing.'' In this work, we examine the evolution of eight large, active instabilities in southe...

Despite constituting 80% of the total number of glaciers in mid- to low-mountain range catchments, the attention paid to very small glaciers (< 0.5 km2) in glacier research remains relatively low. However, glaciers of this size category are expected to undergo dramatic changes. Within Switzerland, more than half are predicted to disappear within th...

Hydrologische und gravitative Naturgefahren stellen eine erhebliche Bedrohung für Gesellschaft, Infrastruktur und Ökosysteme dar und sind daher eine grosse Herausforderung für den ganzen Alpenraum. Hydrologische Gefahren wie Hochwasser und Murgänge werden oft durch extreme meteorologische Bedingungen wie starke Regenfälle und Schneeschmelze ausgelö...

Here, we present a compilation of 95 ice temperature profiles from 85 boreholes from the Greenland ice sheet and peripheral ice caps, as well as local ice caps in the Canadian Arctic. Profiles from only 31 boreholes (36 %) were previously available in open-access data repositories. The remaining 54 borehole profiles (64 %) are being made digitally...

Accurate registration of TLS (Terrestrial Laser Scanner) point clouds is essential for unbiased determination of deformations in long-range geomonitoring. We evaluated the performance of several established registration methods in an ongoing geomonitoring case study. Our results showed that the ICP (Iterative Closest Point)-based methods specifical...

Landslides are a major geohazard that cause thousands of fatalities every year. Despite their importance, identifying unstable slopes and forecasting collapses remains a major challenge. In this study, we use the 7 February 2021 Chamoli rock–ice avalanche as a data-rich example to investigate the potential of remotely sensed datasets for the assess...

Here, we present a compilation of 85 ice temperature profiles from 79 boreholes from the Greenland Ice Sheet and peripheral ice caps, as well as local ice caps in the Canadian Arctic. Only 25 profiles (32 %) were previously available in open-access data repositories. The remaining 54 profiles (68 %) are being made digitally available here for the f...

Large-volume detachments of low-angle mountain glaciers involve the sudden mobilization of large amounts of glacier ice and lithic material in long-runout mass flows. Scientific investigations of these events have only recently brought to light their global occurrence and the similarities in the conditions under which they occur. While this recent...

The mobility of debris flows is highly variable, which makes runout prediction challenging. Numerical runout models are often used to estimate inundation area, flow depth and velocity for debris-flow analyses. Runout models typically use initiation conditions that disregard the fact that debris flows commonly occur in multiple surges. In this work,...

Debris flows affect people and infrastructure around the world, and as a result, many numerical models and modelling approaches have been developed to simulate their impacts. Observations from instrumented debris-flow channels show that variability in inflow depth, velocity, and discharge in real debris flows is much higher than what is typically u...

On 17 October 2015, a large landslide entered the marine waters of Taan Fiord, Alaska, and generated a displacement wave with a 193 m runup. The wave scoured the surrounding hillslopes of soil and vegetation and deposited significant volumes of material into the fjord, onto hillslopes on the opposite side of the fjord, and on top of Tyndall Glacier...

Debris flows affect people and infrastructure around the world, and as a result, many numerical models and modelling approaches have been developed to simulate their impacts. Observations from instrumented debris-flow channels show that variability in inflow depth, velocity and discharge in real debris flows is much higher than what is typically us...

On the 7th of February 2021, a large rock-ice avalanche triggered a debris flow in Chamoli district, Uttarakhand, India, leaving over 200 dead or missing. The rock-ice avalanche originated from a steep, glacierized north-facing slope. In this work, we assess the precursory signs exhibited by this slope prior to the catastrophic collapse. We evaluat...

A deadly cascade A catastrophic landslide in Uttarakhand state in India on February 2021 damaged two hydropower plants, and more than 200 people were killed or are missing. Shugar et al. describe the cascade of events that led to this disaster. A massive rock and ice avalanche roared down a Himalayan valley, turning into a deadly debris flow upstre...

Glacier detachments are a rare, but hazardous, phenomenon of glacier instability, whereof only a handful have been documented to date. Common to all known cases is that many million cubic meters of ice detached from the bed of relatively low-angle valley glaciers and turned into long-runout mass flows. Recently, two such detachments were observed i...

The detachment of large parts of low-angle mountain glaciers resulting in massive ice–rock avalanches have so far been believed to be a unique type of event, made known to the global scientific community first for the 2002 Kolka Glacier detachment, Caucasus Mountains, and then for the 2016 collapses of two glaciers in the Aru range, Tibet. Since 20...

Assessing landslide activity at large scales has historically been a challenging problem. Here, we present a different approach on radar coherence and normalized difference vegetation index (NDVI) analyses – metrics that are typically used to map landslides post-failure – and leverage a time series analysis to characterize the pre-failure activity...

Ice avalanches, sudden large-volume detachments of low-angle mountain glaciers, and glacier surges are glacier instabilities that can pose a significant hazard to mountain communities and infrastructure. Together, these three processes form a continuum of hazards where the volume of mobilized ice is inversely proportional to the surface slope of th...

We presents results from a novel warning and alarm system aimed at predicting and detecting ice avalanches starting on the steep icefall on Bis glacier near the municipality of Randa, canton of Valais, Switzerland. Every 15-20 years, depending on snow conditions, avalanches starting in the icefall reach the valley bottom, where they impact road and...

We use pairs of parallel mounted laser profile scanners to measure main debris-flow variables in two debris-flow channels in central and southern Switzerland. The scanners measure the instantaneous cross-sectional geometry of debris flows at rates of 25–100 Hz, and we apply large-scale particle image velocimetery to estimate velocity. The scanners...

Two notorious avalanche gullies threaten the only access road to Zermatt, Switzerland. Avalanches are released artificially by helicopter blasting whenever conditions permit, and a system of trigger lines has offered additional protection for the last 30 years. In December 2015 we replaced the trigger line system with a state-of-the-art radar-based...

After a rock avalanche in 2009, the Spreitgraben avalanche course in the Bernese Oberland, Switzerland, has experienced extremely erosive debris flows that pose an increasing threat to infrastructure and residents. Following first events, an extensive alarm and research system was installed that is designed to alert residents and automatically clos...

Since 2009 every year several extremely erosive debris-flows occurred in the Spreitgraben near Guttannen. It started with small and harmless flows. Within 3 years they became huge, destructive events with enormous hazard potential. During this period a total amount of 650,000 m3 bedload has been transported into the main river. Strong erosion along...

Viel Schnee heisst nicht unbedingt, dass die Gletscher an Masse zulegen und der Permafrost gut gekühlt bleibt. Es kommt darauf an, wann die weisse Pracht fällt.