A5070337273- Arctic and Antarctic ice dynamics
- Cryospheric studies and observations
- Climate change and permafrost
- Meteorological Phenomena and Simulations
- Methane Hydrates and Related Phenomena
- Geophysical Methods and Applications
- Atmospheric and Environmental Gas Dynamics
- Geotechnical and Geomechanical Engineering
- Climate variability and models
- Tropical and Extratropical Cyclones Research
- Mineral Processing and Grinding
École Polytechnique Fédérale de Lausanne
2021-2023
Swiss Federal Institute for Forest, Snow and Landscape Research
2021-2023
Center for Snow and Avalanche Studies
2020-2023
Carl von Ossietzky Universität Oldenburg
2019
Abstract. Data from the Multidisciplinary drifting Observatory for Study of Arctic Climate (MOSAiC) expedition allowed us to investigate temporal dynamics snowfall, snow accumulation and erosion in great detail almost whole season (November 2019 May 2020). We computed cumulative water equivalent (SWE) over sea ice based on depth density retrievals a SnowMicroPen approximately weekly measured depths along fixed transect paths. used derived SWE cover compare with precipitation sensors...
Abstract. Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact these processes radar signatures is poorly understood. Here, we examine effects over Arctic waveforms backscatter obtained from a surface-based, fully polarimetric Ka- Ku-band at incidence angles between 0∘ (nadir) 50∘. Two wind events in November 2019 during Multidisciplinary drifting Observatory for Study Climate (MOSAiC) expedition are evaluated. During both events, changes...
Abstract Snow plays an essential role in the Arctic as interface between sea ice and atmosphere. Optical properties, thermal conductivity mass distribution are critical to understanding complex system’s energy balance distribution. By conducting measurements from October 2019 September 2020 on Multidisciplinary drifting Observatory for Study of Climate (MOSAiC) expedition, we have produced a dataset capturing year-long evolution physical properties snow surface scattering layer, highly...
Snow and ice topography impact are impacted by fluxes of mass, energy, momentum in Arctic sea ice. We measured the on approximately a 0.5 km
An extensive analysis of Low Level Jets (LLJs) over the Southern North Sea is presented.The study based on observational data from a wind LiDAR and passive microwave radiometer, operated May 2015 to October 2016 FINO1 platform, as well mesoscale simulations by WRF-ARW.Besides evaluations LLJ occurrence, intensity, direction, height, shears boundary layer stability 250 days measurements, two case studies were investigated in detail.It indicates that LLJs are very frequent phenomenon above...
Abstract. Data from the Multidisciplinary drifting Observatory for Study of Arctic Climate (MOSAiC) expedition allowed us to investigate temporal dynamics snowfall, snow accumulation, and erosion in great detail almost whole accumulation season (November 2019 May 2020). We computed cumulative water equivalent (SWE) over sea ice based on depth (HS) density retrievals a SnowMicroPen (SMP) approximately weekly-measured depths along fixed transect paths. Hence, SWE considers surface...
Abstract. The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these polar regions covered by sea ice, wind is relatively strong due absence obstructions redistributes large part deposited snow mass, which complicates estimates for precipitation hardly distinguishable from blowing or drifting snow. Moreover, mass balance in ice system still poorly understood, notably complex structure its surface. Quantitatively assessing distribution on...
Abstract. Snow significantly impacts the seasonal growth of Arctic sea ice due to its thermally insulating properties. Various measurements and parametrizations thermal properties exist, but an assessment entire evolution conductivity snow resistance is hitherto lacking. Using comprehensive data set from MOSAiC expedition, we have evaluated for first time snow's on different ages (leads, second-year ice) topographic features (ridges). Combining measurement assessing robustness against...
Abstract Snow depth on sea ice is an Essential Climate Variable and a major source of uncertainty in satellite altimetry‐derived thickness. During winter the MOSAiC Expedition, “KuKa” dual‐frequency, fully polarized Ku‐ Ka‐band radar was deployed “stare” nadir‐looking mode to investigate possibility combining these two frequencies retrieve snow depth. Three approaches were investigated: dual‐polarization waveform shape, compared independent measurements. Novel yielded r 2 values up 0.77....
Abstract. Wind transport alters the snow topography and microstructure on sea ice through redistribution controlled by deposition erosion. The impact of these processes radar signatures is poorly understood. Here, we examine effects Arctic from Ka- Ku-band signatures. Measurements were obtained during two wind events in November 2019 MOSAiC expedition. During both events, changes waveforms backscatter coincident with surface height measured a terrestrial laser scanner are observed. At...
Abstract. Snow significantly impacts the seasonal growth of Arctic sea ice due to its thermally insulating properties. Various measurements and parameterizations thermal properties exist, but an assessment entire evolution conductivity snow resistance is hitherto lacking. Using comprehensive dataset from Multidisciplinary Drifting Observatory for Study Climate (MOSAiC) expedition, we have evaluated first time snow's denser snow-ice interface layers' above different ages (refrozen leads,...
<p>Sea ice plays a critical role in the Arctic climate system, regulating much of energy transfer between ocean and atmosphere. Repeat measurements mass balance at discrete points allow us to determine direct response sea environmental conditions. We installed network measurement sites across MOSAiC Central Observatories, distributed over diverse range types features. The were composed gridded arrays 9-17 hotwire thickness gauges, each paired with surface ablation stake. Seven...
A 3D-snow modeling setup including snow transport and temporally changing detailed properties was adjusted for Arctic sea ice.• The model reproduces with high accuracy, performed well in modelling the surface density some uncertainty.• will allow to investigate insulating effect on spatial ice thermodynamics, especially ridged areas.
<p>Several factors, including the movement and distribution of seawater, amount precipitation, presence sea ice influence Arctic Ocean's hydrology. Snow plays a pivotal role in water cycle as it influences spatial fresh available region. In Arctic, precipitation is scarce, snow accumulation rates are low. Consequently, deposited on top remains exposed surface for several months. During this time, post-depositional processes (i.e., metamorphism, sublimation) wind...
Snow plays a crucial role in the heat transfer between ocean and atmosphere sea ice due to its insulating properties. However, wind-induced transport causes snow distribution be inhomogeneous, as forms dunes accumulates mostly around pressure ridges and, leading heterogeneous underlying growth melt. While models can help understand complex interactions of ice, there is currently no 3D cover model for that considers detailed This study presents first application 3D-snow cover-atmosphere...
Earth and Space Science Open Archive PosterOpen AccessYou are viewing the latest version by default [v1]Snow microstructure on sea ice- first results from MOSAiC expeditionAuthorsAmyMacfarlaneiDDavid NicholasWagneriDRuzicaDadicStefanHämmerleMartinSchneebeliiDSee all authors Amy MacfarlaneiDCorresponding Author• Submitting AuthorWSL Institute for Snow Avalanche Research SLFiDhttps://orcid.org/0000-0002-1638-8885view email addressThe was not providedcopy addressDavid Nicholas WagneriDWSL...