Publications de Charles Fierz | EPFL Graph Search

Representation of Horizontal Transport Processes in Snowmelt Modeling by Applying a Footprint Approach

Michael Lehning, Sebastian Schlögl, Charles Fierz

The energy balance of an alpine snow cover significantly changes once the snow cover gets patchy. The local advection of warm air causes above-average snow ablation rates at the upwind edge of the snow patch. As lateral transport processes are typically no ...

FRONTIERS MEDIA SA2018

Investigation of a wind-packing event in Queen Maud Land, Antarctica

Michael Lehning, Nander Wever, Christian Gabriel Sommer, Charles Fierz

Surface snow in polar and mountainous regions is often mobile and this mobility influences surface mass balance and isotopic composition before final deposition, which is poorly understood thus far. In December 2016 and January 2017, during a field campaig ...

COPERNICUS GESELLSCHAFT MBH2018

ESM-SnowMIP: assessing snow models and quantifying snow-related climate feedbacks

Nander Wever, Huanyuan Shan, Charles Fierz, Tao Wang, Xing Fang

This paper describes ESM-SnowMIP, an international coordinated modelling effort to evaluate current snow schemes, including snow schemes that are included in Earth system models, in a wide variety of settings against local and global observations. The proj ...

COPERNICUS GESELLSCHAFT MBH2018

Wind Tunnel Experiments: Influence of Erosion and Depositionon Wind-Packing of New Snow

Michael Lehning, Christian Gabriel Sommer, Charles Fierz

2018

Wind tunnel experiments: saltation is necessary for wind-packing

Michael Lehning, Christian Gabriel Sommer, Charles Fierz

Wind-packed snow in the form of slabs or crusts is an important part of alpine and polar snow covers. Yet, the formation process of such layers is poorly understood. For example, it remains unclear whether drifting snow is necessary for wind-packing or not ...

International Glaciological Society2017

Impact of climate change in Switzerland on socioeconomic snow indices

Michael Lehning, Charles Fierz

Snow is a key element for many socioeconomic activities in mountainous regions. Due to the sensitivity of the snow cover to variations of temperature and precipitation, major changes caused by climate change are expected to happen. We analyze the evolution ...

Springer Verlag2017

Simulating ice layer formation under the presence of preferential flow in layered snowpacks

Michael Lehning, Nander Wever, Sebastian Würzer, Charles Fierz

For physics-based snow cover models, simulating the formation of dense ice layers inside the snowpack has been a long-time challenge. Their formation is considered to be tightly coupled to the presence of preferential flow, which is assumed to happen throu ...

Copernicus GmbH2016

Wind slab formation in snow: experimental setup and first results

Michael Lehning, Christian Gabriel Sommer, Charles Fierz

Geophys . Res. Abstr. 18: EGU2016‐11274. The formation of wind-hardened surface layers, also known as wind slabs or wind crusts, is studied. Better knowledge about which processes and parameters are important will lead to an improved understanding of the m ...

2016

Assessing wet snow avalanche activity using detailed physics based snowpack simulations

Nander Wever, Charles Fierz

Water accumulating on microstructural transitions inside a snowpack is often considered a prerequisite for wet snow avalanches. Recent advances in numerical snowpack modeling allow for an explicit simulation of this process. We analyze detailed snowpack si ...

American Geophysical Union2016

A new ring‐shaped wind tunnel facility to study wind‐packing of snow

Michael Lehning, Christian Gabriel Sommer, Charles Fierz

A new wind tunnel was designed and built at SLF. The facility is ring-shaped to simulate an infinite fetch. This is important for experiments where the observed processes have a slow time scale (minutes to hours). The wind tunnel was developed to study the ...

University de Genève2016