Publications de Benjamin Andreas Walter

Radar measurements of blowing snow off a mountain ridge

Michael Lehning, Wolf Hendrik Huwald, Josué Etienne Gehring, Benjamin Andreas Walter

Modelling and forecasting wind-driven redistribution of snow in mountainous regions with its implications on avalanche danger, mountain hydrology or flood hazard is still a challenging task often lacking in essential details. Measurements of drifting and b ...

2020

Experimental assessment of Owen's second hypothesis on surface shear stress induced by a fluid during sediment saltation

Michael Lehning, Benjamin Andreas Walter

A widely used, yet thus far unproven, fluid dynamical hypothesis originally presented by P. R. Owen 50years ago, states that the surface shear stress induced by a fluid on the ground during equilibrium sediment saltation is constant and independent of the ...

American Geophysical Union2014

Snow particle characteristics in the saltation layer

Michael Lehning, Benjamin Andreas Walter

Shadowgraphy was employed to study snow saltation in boundary-layer wind tunnel experiments with fresh, naturally deposited snow. The shadowgraphy method allowed for a temporally and spatially high-resolution investigation of snow particle characteristics ...

Int Glaciol Soc2014

Planck 2013 results. XXVIII. The Planck Catalogue of Compact Sources

Julien Lesgourgues, Xin Chen, Fabio Finelli, Benjamin Andreas Walter

The Planck Catalogue of Compact Sources (PCCS) is the catalogue of sources detected in the first 15 months of Planck operations, the "nominal" mission. It consists of nine single-frequency catalogues of compact sources, both Galactic and extragalactic, det ...

Edp Sciences S A2014

Measurements of the pore-scale water flow through snow using Fluorescent Particle Tracking Velocimetry

Michael Lehning, Benjamin Andreas Walter

Fluorescent Particle Tracking Velocimetry (FPTV) measurements of the pore-scale water flow through the pore space of a wet-snow sample are presented to demonstrate the applicability of this measurement technique for snow. For the experiments, ice-cooled wa ...

American Geophysical Union2013

Wind Tunnel Studies of Shear Stress Partitioning in Live Plant Canopies

Benjamin Andreas Walter

The earth's surface is permanently exposed to the atmosphere and accordingly to strong wind forces in many regions. Aerodynamic entrainment, transport and redeposition of sand, soil or snow are able to considerably reshape the surface morphology and influe ...

EPFL2012

Shear-Stress Partitioning in Live Plant Canopies and Modifications to Raupach's Model

Michael Lehning, Benjamin Andreas Walter

The spatial peak surface shear stress on the ground beneath vegetation canopies is responsible for the onset of particle entrainment and its precise and accurate prediction is essential when modelling soil, snow or sand erosion. This study investigates she ...

Springer Netherlands2012

Spatio-Temporal Surface Shear-Stress Variability in Live Plant Canopies and Cube Arrays

Michael Lehning, Katherine Colby Leonard, Benjamin Andreas Walter

This study presents spatiotemporally-resolved measurements of surface shear-stress tau (s) in live plant canopies and rigid wooden cube arrays to identify the sheltering capability against sediment erosion of these different roughness elements. Live plants ...

Springer Netherlands2011

Measurements of surface shear stress distribution in real plant canopies

Michael Lehning, Katherine Colby Leonard, Benjamin Andreas Walter

2011