Publications associées à Sea ice growth processes

The molecular scale mechanism of deposition ice nucleation on silver iodide

Athanasios Nenes, Mária Lbadaoui-Darvas, André Welti

Heterogeneous ice nucleation is a ubiquitous process in the natural and built environment. Deposition ice nucleation, i.e. heterogeneous ice nucleation that - according to the traditional view - occurs in a subsaturated water vapor environment and in the a ...

Royal Soc Chemistry2024

Influence of sun cups on surface albedo of wet Alpine snowpack

Michael Lehning, Mathias Thierry Pierre Bavay, Francesca Carletti

In high elevation Alpine areas, characterised by high snow accumulation and radiation-driven melt processes, the formation of peculiar ablation features called sun cups can be observed. Sun cups likely influence the energy and mass balance of the wet snowp ...

2024

The role of secondary ice production in mixed-phase clouds

Paraskevi Georgakaki

Clouds are omnipresent in the Earth's atmosphere. Their phase composition significantly modulates their interaction with solar and terrestrial radiation, as well as precipitation formation. Particularly for clouds containing both phases, known as mixed-pha ...

EPFL2023

Polar oceans and sea ice in a changing climate

Julia Schmale, Hélène Paule Angot, Jenny Thomas

Polar oceans and sea ice cover 15% of the Earth’s ocean surface, and the environment is changing rapidly at both poles. Improving knowledge on the interactions between the atmospheric and oceanic realms in the polar regions, a Surface Ocean–Lower Atmospher ...

2023

Monolithic InSb nanostructure photodetectors on Si using rapid melt growth

Anna Fontcuberta i Morral, Nicholas Paul Morgan, Heera Menon

Monolithic integration of InSb on Si could be a key enabler for future electronic and optoelectronic applications. In this work, we report the fabrication of InSb metal-semiconductor-metal photodetectors directly on Si using a CMOS-compatible process known ...

ROYAL SOC CHEMISTRY2023

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

Observing the Central Arctic Atmosphere and Surface with University of Colorado uncrewed aircraft systems

Julia Schmale, Radiance Flore Aurore Calmer

Over a five-month time window between March and July 2020, scientists deployed two small uncrewed aircraft systems (sUAS) to the central Arctic Ocean as part of legs three and four of the MOSAiC expedition. These sUAS were flown to measure the thermodynami ...

NATURE PORTFOLIO2022

Water vapor transport in snowpacks

Mahdi Jafari

This thesis is an in-depth treatment of water vapor transport in snowpacks and its impacts on snow structure. The aim is to better understand this transport process and to lay the basis for a model representation in physics-based multi-layer snow models. O ...

EPFL2022

Introducing CRYOWRF v1.0: multiscale atmospheric flow simulations with advanced snow cover modelling

Varun Sharma, Michael Lehning, Franziska Gerber

Accurately simulating snow-cover dynamics and the snow-atmosphere coupling is of major importance for topics as wide-ranging as water resources, natural hazards and climate change impacts with consequences for sea-level rise. We present a new modelling fra ...

2023

The Impact of Diffusive Water Vapor Transport on Snow Profiles in Deep and Shallow Snow Covers and on Sea Ice

Michael Lehning, Varun Sharma, Adrien Michel, Mahdi Jafari, Margaux Caroline Patricia Couttet, Nander Wever, Isabelle Amandine Gouttevin

Water vapor transport has been highlighted as a critical process in Arctic snowpacks, shaping the snow cover structure in terms of density, thermal conductivity, and temperature profile among others. Here, we present an attempt to describe the thermally-in ...

2020

Controls on the diurnal streamflow cycles in two subbasins of an alpine headwater catchment

Marc Parlange, Steven Vincent Weijs, Marc Calaf Bracons, Holly Jayne Oldroyd, Raphaël Mutzner

In high-altitude alpine catchments, diurnal streamflow cycles are typically dominated by snowmelt or ice melt. Evapotranspiration-induced diurnal streamflow cycles are less observed in these catchments but might happen simultaneously. During a field campai ...

American Geophysical Union2015

Estimating the ice thickness of shallow glaciers from surface topography and mass-balance data with a shape optimization algorithm

Marco Picasso, Laurent Michel, Heinz Blatter, Martin Funk

A shape optimization algorithm is presented that estimates the ice thickness distribution within a three-dimensional, shallow glacier, given a transient surface geometry and a mass-balance distribution. The approach is based on the minimization of the surf ...

Pergamon-Elsevier Science Ltd2014

Estimating the ice thickness of mountain glaciers with a shape optimization algorithm using surface topography and mass-balance

Marco Picasso, Laurent Michel, Heinz Blatter, Martin Funk

We present a shape optimization algorithm to estimate the ice thickness distribution within a two-dimensional, non-sliding mountain glacier, given a transient surface geometry and a mass-balance distribution. The approach is based on the minimization of th ...

De Gruyter2014

The structure and effect of suture zones in the Larsen C Ice Shelf, Antarctica

Konrad Steffen

Ice shelf fractures frequently terminate where they encounter suture zones, regions of material heterogeneity that form between meteoric inflows in ice shelves. This heterogeneity can consist of marine ice, meteoric ice with modified rheological properties ...

Amer Geophysical Union2014

Use of a multilayer snow model to assess grazing conditions for reindeer

Michael Lehning

High-density snow layers deteriorate grazing conditions for reindeer during winter. We compare two different methods for identifying past winters with difficult grazing conditions for reindeer in Kautokeino, northern Norway. A long-term climate analysis ba ...

Int Glaciol Soc2013

The influence of winds, sea-surface temperature and precipitation anomalies on Antarctic regional sea-ice conditions during IPY 2007

Katherine Colby Leonard

The 2007 International Polar Year (IPY) in the Antarctic was distinguished by strong regional and seasonal ice-atmosphere-ocean anomalies associated with an overall weakening of the prevailing westerly circulation. Here we assess the ice-atmosphere-ocean c ...

2011

Impedance measurements of the complex dielectric permittivity of sea ice at 50 MHz: pore microstructure and potential for salinity monitoring

Guy Joseph Günter Dubuis

We report impedance measurements of the complex dielectric permittivity epsilon = epsilon' - j epsilon '' of sea ice and laboratory-grown NaCl single crystals using 50 MHz Stevens Water Monitoring Systems Hydra Probes. Temperature cycling of the single-cry ...

2009