A5066809808- Cryospheric studies and observations
- Landslides and related hazards
- Winter Sports Injuries and Performance
- Climate change and permafrost
- Hydrology and Sediment Transport Processes
- Seismic Waves and Analysis
- Geological formations and processes
- Methane Hydrates and Related Phenomena
- Seismic Imaging and Inversion Techniques
- Arctic and Antarctic ice dynamics
- earthquake and tectonic studies
- Geology and Paleoclimatology Research
- Underwater Acoustics Research
- Soil erosion and sediment transport
- Flood Risk Assessment and Management
- Seismology and Earthquake Studies
- Rock Mechanics and Modeling
- Geotechnical and Geomechanical Engineering
- Hydrology and Watershed Management Studies
- Granular flow and fluidized beds
- Geological Studies and Exploration
- Adventure Sports and Sensation Seeking
- Indigenous Studies and Ecology
- Polar Research and Ecology
- Traumatic Brain Injury Research
Université Grenoble Alpes
2012-2024
Centre National de la Recherche Scientifique
2013-2024
Institut des Géosciences de l'Environnement
2017-2024
Institut de Recherche pour le Développement
2017-2024
Institut polytechnique de Grenoble
2018-2024
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2024
Institut des Sciences de la Terre
2012-2022
Université Gustave Eiffel
2012-2022
GFZ Helmholtz Centre for Geosciences
2016-2019
California Institute of Technology
2013-2018
A sudden outburst of erosion Glacial lake floods (GLOFs) are exactly what they sound like. The emptying a glacial in high-topography regions like the Himalaya can quickly destroy everything its path. Cook et al. intercepted GLOF Bhotekoshi and Sunkoshi river valleys central Nepal as were monitoring region aftermath 2015 Gorkha earthquake. They found that massive amount occurred during flood, which suggests GLOFs may be primary factor landscape evolution for these regions. Science , this issue p. 53
Abstract Previous studies suggest that the seismic noise induced by rivers may be used to infer river transport properties, and previous theoretical work showed bedload sediment flux can inverted from data. However, lack of a framework relating water flow prevents these providing accurate fluxes quantitative information on processes. Here we propose forward model caused turbulent flow. In agreement with observations, modeled flow‐induced operates at lower frequencies than bedload‐induced...
Abstract Water that pressurizes the base of glaciers and ice sheets enhances glacier velocities modulates glacial erosion. Predicting flow erosion therefore requires knowledge subglacial channel evolution, which remains observationally limited. Here we demonstrate detailed analysis seismic ground motion caused by water at Mendenhall Glacier (Alaska) allows for continuous measurement daily to subseasonal changes in basal pressure gradient, size, sediment transport. We observe intermittent...
Abstract Bedload transport drives morphological changes in gravel‐bed streams and sediment transfer catchments. The large impact forces associated with bedload motion its highly dynamic spatiotemporal nature make it difficult to monitor the field. In this study, we revise a physically‐based model of bedload‐induced seismic ground proposed by Tsai et al. (2012) apply invert flux from measurements alongside an Alpine stream. First, constrain response braided river reach simple active...
Abstract Recent advances in fluvial seismology have provided solid observational and theoretical evidence that near‐river seismic ground motion may be used to monitor quantify coarse sediment transport. However, inversions of transport rates from observations not been fully tested against independent measurements, thus unknown but potentially large uncertainties. In the present study, we provide first robust test existing theory by conducting dedicated experiments a flume laboratory under...
Abstract. Water flowing below glaciers exerts a major control on glacier basal sliding. However, our knowledge of the physics subglacial hydrology and its link with sliding is limited because lacking observations. Here we use 2-year-long dataset made on-ice-measured seismic in situ-measured speed Glacier d'Argentière (French Alps) to investigate channels potential Using dedicated theory concomitant measurements water discharge, quantify temporal changes channels' hydraulic radius pressure...
Significance Our understanding of when, where, and under which conditions subglacial water flow favors or impedes glacier remains uncertain mainly because sparse field observations. This strongly limits our capability to assess the susceptibility glaciers ice sheets a future increase in meltwater input due climate warming. Here, we overcome classic observational difficulties by establishing an innovative seismic-based approach. From dense seismic array observations, retrieve with...
Abstract Below hard‐bedded glaciers, both basal friction and distributed subglacial drainage are thought to be controlled by a network of cavities. Previous coupled hydro‐mechanical models, however, describe cavity‐driven hydraulic transmissivity independently, resulting in physically inconsistent cavity evolution between the two components models. Here, we overcome this issue describing system using common cavity‐evolution description, that governs transient transmissivity. We show our...
Abstract Surface melt forces summertime ice‐flow accelerations on glaciers and ice sheets. Here, we show that large meltwater‐forced also occur during wintertime in Greenland. We document supraglacial lakes (SGLs) draining cascades at unusually high elevation, causing an expansive flow acceleration over a ∼5,200 km 2 region winter. The three‐component interferometric surface velocity field decomposition modeling reveal the underlying flood propagation with unprecedented detail as it traveled...
We present a simple and analytical ocean boundary layer‐sea ice coupled dynamical model that we apply to the modeling of Arctic sea motion in frequency domain, particularly inertial range. This study further complements our related work an unpublished paper where cover response Coriolis forcing has been studied. allows interpretation spatial, seasonal pluriannual dependence magnitude oscillations detailed terms mechanical behavior cover. In this model, is simplified through introduction...
Significance Large structures generally fail under stresses significantly lower than those of small ones. This is the size effect on strength, one oldest problems engineering, already discussed by Leonardo da Vinci and Edmé Mariotte centuries ago. One classical explanation weakest-link hypothesis: The larger “chain” is, probability to find a weak link whose breaking will set failure whole chain. We show, however, that it irrelevant in case compressive loading, situation particularly crucial...
ABSTRACT The evolution of glaciers and ice sheets depends on processes in the subglacial environment. Shear seismicity along ice–bed interface provides a window into these processes. Such requires rapid loss strength that is typically ascribed to rate-weakening friction, i.e., decreasing friction with sliding or rate. Many experiments have investigated glacial materials at temperate conditions typical fast flowing glacier beds. To our knowledge, however, studies all found rate-strengthening...
Abstract Hysteresis in the relationship between bed load transport and river stage is a well‐documented phenomenon with multiple known causes. Consequently, numerous studies have interpreted hysteresis seismic ground motion near rivers some measure of flow strength (i.e., discharge or stage) as signature transport. Here we test this hypothesis Erlenbach stream (Swiss Prealps) using metric to quantitatively compare data recorded by geophones attached beneath steel plates within streambed,...
Abstract. Ambient noise seismology has revolutionized seismic characterization of the Earth's crust from local to global scales. The estimate Green's function (GF) between two receivers, representing impulse response elastic media, can be reconstructed via cross-correlation ambient seismograms. A homogenized wave field illuminating propagation medium in all directions is a prerequisite for obtaining an accurate GF. For data recorded on glaciers, this condition imposes strong limitations GF...
Abstract. On glaciers and ice sheets, identifying the relationship between velocity traction is critical to constrain bed physics that controls flow. Yet in Greenland, these relationships remain unquantified. We determine spatial all eight major drainage catchments of Greenland. The basal estimated using three different methods over large grid cells minimize interpretation biases associated with unconstrained rheologic parameters used numerical inversions. find are consistent our current...
Abstract. Glacier internal deformation is usually described by Glen's flow law using two material parameters: the creep factor (A) and exponent (n). However, values of these parameters their spatial temporal variability are rather uncertain due to difficulty in quantifying strain stress fields at natural scales. In this study, we combine 1-year-long continuous measurements borehole inclinometry surface velocity with three-dimensional full-Stokes ice modeling infer rheologies sliding...
Slip at the ice-bed interface (basal motion) dominates flow of many glaciers, and it is uncertain whether this velocity component will increase or slow in a warmer world. Past results from an idealized flowline glacier model show that declining basal motion induces two-phase response initially accelerates retreat warming climate on multidecadal timescale but lessens centennial-scale mass loss. In present work, we utilize existing field-collected remotely-sensed constraints ice thickness,...
Understanding the physical laws governing glacier and ice sheet basal sliding speed is crucial for accurately predicting their dynamics contribution to sea-level rise. However, controlled by complex processes linked subglacial hydrology, which remains difficult constrain. Previous studies based on Argentière (France) suggest a simplification of law describing long-term evolution velocity, proposing that water pressure hard-bedded glaciers determined shear stress condition. The...
River-ice affects hydraulics and sediment transport that may in turn influence channel morphology. However, scientific understanding of sub-ice flows is limited by the difficulty accessing ice-covered bed banks. During periods stable ice cover, hydraulic studies usually assume cover free-floating can therefore move vertically to accommodate changes river discharge. often fixed place, attached In this case, increasing discharge forced under causing pressurized typified higher flow velocities...
Abstract. Hydraulic processes impact viscous and brittle ice deformation. Water-driven fracturing as well turbulent water flow within beneath glaciers radiate seismic waves which provide insights into otherwise hard-to-access englacial subglacial environments. In this study, we analyze glaciohydraulic tremors recorded by four arrays installed in different parts of Glacier de la Plaine Morte, Switzerland. Data were during the 2016 melt season including sudden drainage an ice-marginal lake....
Abstract. Mass balance observations are very useful to assess climate change in different regions of the world. As opposed glacier-wide mass balances which influenced by dynamic response each glacier, point provide a direct climatic signal that depends on surface accumulation and ablation only. Unfortunately, major efforts required conduct situ measurements glaciers. Here, we propose new approach determines from remote sensing observations. We call this geodetic balance. From modelling...
Abstract. On 2 October 2020, the Maritime Alps in southern France were struck by devastating Storm Alex, which caused locally more than 600 mm of rain less 24 h. The extreme rainfall and flooding destroyed regional stream gauges. That hinders our understanding spatial temporal dynamics rainfall–runoff processes during storm. Here, we show that seismological observations from permanent seismic stations constrain these at a catchment scale. analysis power, peak frequency, back azimuth provides...