Publications de David Nicholas Wagner

Retrieval of Snow Depth on Arctic Sea Ice From Surface-Based, Polarimetric, Dual-Frequency Radar Altimetry

Snow depth on sea ice is an Essential Climate Variable and a major source of uncertainty in satellite altimetry-derived sea ice thickness. During winter of the MOSAiC Expedition, the "KuKa" dual-frequency, fully polarized Ku- and Ka-band radar was deployed ...

2023

Spatio-Temporal Dynamics of Snow on Central Arctic Sea Ice and its Implications

David Nicholas Wagner

This thesis presents a comprehensive investigation of the interaction between precipitation and wind-induced erosion and deposition of snow on Arctic sea ice. The study uses observations from the 2019-2020 MOSAiC expedition and makes use of the 3D snow cov ...

EPFL2023

Wind Transport of Snow Impacts Ka- and Ku-band Radar Signatures on Arctic Sea Ice

Marc Schneebeli Zeugin, David Nicholas Wagner

Wind transport alters the snow topography and microstructure on sea ice through snow redistribution controlled by deposition and erosion. The impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistrib ...

2023

Modeling the small-scale deposition of snow onto structured Arctic sea ice during a MOSAiC storm using snowBedFoam 1.0

Michael Lehning, Océane Hames, Marc Schneebeli Zeugin, David Nicholas Wagner, Mahdi Jafari

The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these polar regions covered by sea ice, the wind is relatively strong due to the absence of obstructions and redistributes a large part of the depos ...

COPERNICUS GESELLSCHAFT MBH2022

Snowfall and snow accumulation during the MOSAiC winter and spring seasons

Michael Lehning, Marc Schneebeli Zeugin, David Nicholas Wagner, Markus Frey, Marc Oggier

Data from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition allowed us to investigate the temporal dynamics of snowfall, snow accumulation and erosion in great detail for almost the whole accumulation season (No ...

COPERNICUS GESELLSCHAFT MBH2022

Overview of the MOSAiC expedition: Snow and sea ice

David Nicholas Wagner

Year-round observations of the physical snow and ice properties and processes that govern the ice pack evolution and its interaction with the atmosphere and the ocean were conducted during the Multidisciplinary drifting Observatory for the Study of Arctic ...

2022

Modelling the small-scale deposition of snow onto structured Arctic sea ice during a MOSAiC storm using snowBedFoam 1.0

Michael Lehning, Océane Hames, Mahdi Jafari, Marc Schneebeli Zeugin, David Nicholas Wagner

The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these regions, the wind has a substantial effect and redistributes a large part of the snow, which complicates precipitation estimates. Moreover, th ...

2021

Snowfall and snow accumulation processes during the MOSAiC winter and spring season

Michael Lehning, Marc Schneebeli Zeugin, David Nicholas Wagner, Markus Frey, Marc Oggier

Data from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition allowed us to investigate the temporal dynamics of snowfall, snow accumulation, and erosion in great detail for almost the whole accumulation season (N ...

2021

Electron and Impurity Transport Studies in the TCV Tokamak

Dávid Wágner, David Nicholas Wagner

EPFL2013

Recent TCV results – innovative plasma shaping to improve plasma properties and insight

Basil Duval, Olivier Sauter, Stefano Coda, Timothy Goodman, Jean-Marc Moret, Laurent Villard, Benoît Labit, Laurie Porte, Holger Reimerdes, Alexander Karpushov

2012