Publications related to Till | EPFL Graph Search

Global emergent responses of stream microbial metabolism to glacier shrinkage

Tom Ian Battin, Hannes Markus Peter, Massimo Bourquin, Nicola Deluigi, Tyler Joe Kohler, Michail Styllas

Most cryospheric ecosystems are energy limited. How their energetics will respond to climate change remains largely unknown. This is particularly true for glacier-fed streams, which interface with the cryosphere and initiate some of Earth's largest river s ...

Nature Portfolio2024

Snowfall deposition in mountainous terrain: a statistical downscaling scheme from high-resolution model data on simulated topographies

Michael Lehning

One of the primary causes of non-uniform snowfall deposition on the ground in mountainous regions is the preferential deposition of snow, which results from the interaction of near-surface winds with topography and snow particles. However, producing high-r ...

Frontiers Media Sa2024

Ecosystem engineering by periphyton in Alpine proglacial streams

Tom Ian Battin, Davide Mancini, Marc Aguet, Adrijan Selitaj, Matteo Roncoroni

Stream periphytons are candidate ecosystem engineers in proglacial margins. Here, we quantify the extent to which they are engineers for the case of hillslope-fed tributaries in the terrace zones of proglacial margin alluvial plains. Candidate ecosystem en ...

WILEY2023

The biofilm ecology of proglacial floodplain streams

Jade Brandani

Glacial forelands figure among the most dynamic landscapes on Earth, and their formation is currently accelerating given glacier shrinkage. Draining these forelands are streams hosting unique microbial communities, which have the capacity to impact both th ...

EPFL2023

A Depth-Averaged Material Point Method for Shallow Landslides: Applications to Snow Slab Avalanche Release

Johan Alexandre Philippe Gaume, Lars Kristoffer Uhlen Blatny, Bertil Trottet, Denis Aloyse Joseph Steffen, Louis Marie Cédric Guillet

Shallow landslides pose a significant threat to people and infrastructure. Despite significant progress in the understanding of such phenomena, the evaluation of the size of the landslide release zone, a crucial input for risk assessment, still remains a c ...

AMER GEOPHYSICAL UNION2023

The Biogeochemical Legacy of Arctic Subglacial Sediments Exposed by Glacier Retreat

Tyler Joe Kohler

During past periods of advance, Arctic glaciers and ice sheets overrode soil, sediments, and vegetation and buried significant stores of organic matter (OM); these glaciers are now shrinking rapidly due to climate warming. Little is known about the biogeoc ...

2022

Experimental Study on Bedload Transport and Bedforms: Behaviour and Interplay in Steep Turbulent Streams

Ivan Pascal

In mountain regions, steep streams play an important role in water and sediment connectivity. In these highly dynamic systems, water flow features, sediment fluxes and stream morphologies are tightly interlinked over a broad range of temporal and spatial s ...

EPFL2022

Snapshots of mean ocean temperature over the last 700,000 yr using noble gases in the EPICA Dome C ice core

Adrien Michel

Together with the latent heat stored in glacial ice sheets the ocean heat uptake carries the lion’s share of glacial/interglacial changes in the planetary heat content but little direct information on the global mean ocean temperature (MOT) is available to ...

2021

Assessing the impact of ground ice degradation on high mountain lake environments (Lago Nero catchment, Swiss Alps)

Nicola Deluigi, Monica Bulgheroni

In high mountain hydrosystems, glacial meltwater composition is potentially affected by the degradation of alpine permafrost terrains and ground ice bodies releasing atmospheric pollutants that have been stored in permafrost terrains for several decades. I ...

SPRINGER BASEL AG2020

Design of sediment detention basins: Scaled model experiments and application

Anton Schleiss, Sebastian Schwindt, Mona Jafarnejad Chaghooshi, Anita Hélène Roth

Sediment detention basins are implemented on mountain rivers to trap solid material that may aggravate the flooding of downstream settlements. However, retention structures built in the past may unnecessarily retain sediment during non-hazardous flood even ...

2020

Preferential Deposition of Snow and Dust Over Hills: Governing Processes and Relevant Scales

Michael Lehning, Marc Parlange, Francesco Comola, Marco Giovanni Giometto

Preferential deposition of snow and dust over complex terrain is responsible for a wide range of environmental processes and accounts for a significant source of uncertainty in the surface mass balances of cold and arid regions. Despite the growing body of ...

2019

Silicon isotopes in Arctic and sub-Arctic glacial meltwaters: the role of subglacial weathering in the silicon cycle

Tyler Joe Kohler

Glacial environments play an important role in high-latitude marine nutrient cycling, potentially contributing significant fluxes of silicon (Si) to the polar oceans, either as dissolved silicon (DSi) or as dissolvable amorphous silica (ASi). Silicon is a ...

2019

The performance of collars on scour reduction at tandem piers aligned with different skew angles

Anton Schleiss, Giovanni De Cesare, Sargol Memar

Local scouring is a leading cause of bridge collapses. To protect bridges against local scouring, different countermeasures have been proposed and tested in the literature. In this study, the performance of collars was evaluated for scour reduction at two ...

2020

Catchment drainage network scaling laws found experimentally in overland flow morphologies

David Andrew Barry, Andrea Rinaldo, Paolo Perona, Mohsen Cheraghi

The scaling relation between the drainage area and stream length (Hack’s law), along with exceedance probabilities of drainage area, discharge and upstream flow network length are well known for channelized fluvial regions. We report here on a laboratory e ...

2018

Entrainment, transport and deposition of sediment by saline gravity currents

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Carmelo Juez Jiménez, Jessica Zordan

Few studies have addressed simultaneously the feedback between the hydrodynamics of a gravity cur- rent and the geomorphological changes of a mobile bed. Hydrodynamic quantities such as turbulent and mean velocities, bed shear stress and turbulent stresses ...

2018

Sediment balance of a cascade of alpine reservoirs based on multi-decadal data records

Anton Schleiss, Pedro Filipe De Almeida Manso, Sebastián Guillén Ludeña

Reservoir sedimentation is a major concern in the operational management of dams and appurtenant structures. The increasing volume of sediments deposited in reservoirs leads to a loss of water storage, undermining the purpose itself of the dam for human us ...

2018

Large Eddy Simulations of sediment entrainment induced by a lock-exchange gravity current

Carmelo Juez Jiménez, Jessica Zordan, Foteini Kyrousi, Alessandro Leonardi

Large Eddy simulations of lock-exchange gravity currents propagating over a mobile reach are presented. The numerical setting allows to investigate the sediment pick up induced by the currents and to study the underlying mechanisms leading to sediment entr ...

2018

Geomorphic work by gravity currents with varying initial conditions

Jessica Zordan

Gravity currents are density-driven flows that are able to transport high amounts of sediment and are responsible of great geomorphic changes. Moreover they can have severe repercussions on the environment since they are conveyors of substances, e.g. pollu ...

EPFL2018

Energy- and momentum-conserving model of splash entrainment in sand and snow saltation

Michael Lehning, Francesco Comola

Despite being the main sediment entrainment mechanism in aeolian transport, granular splash is still poorly understood. We provide a deeper insight into the dynamics of sand and snow ejection with a stochastic model derived from the energy and momentum con ...

American Geophysical Union2017

Analysis of mechanical-hydraulic bedload deposition control measures

Anton Schleiss, Giovanni De Cesare, Mário Jorge Rodrigues Pereira Da Franca, Sebastian Schwindt

During floods, the bedload transport of steep headwaters can exceed the hydraulic transport capacity of milder downstream reaches where settlements are often situated. Therefore, sediment retention barriers are typically installed upstream of such sensible ...

Elsevier2017