Publications related to Antarctic ice sheet

On the importance of the humidity flux for the surface mass balance in the accumulation zone of the Greenland Ice Sheet

It is highly uncertain how the humidity flux between the snow surface and the atmosphere contributes to the surface mass balance (SMB) of the interior Greenland Ice Sheet (GrIS). Due to sparse observations, evaluations of the simulated humidity flux are li ...

Copernicus Gesellschaft Mbh2024

Assessing sublimation during snow transport and sublimation effects on the isotopic composition of water vapor

Armin Sigmund

Sublimation influences the water storage in snow covers and glaciers, which is important for water use and projections of the sea level rise. Yet, it is challenging to quantify sublimation for large areas or in conditions of snow transport. In-situ measure ...

EPFL2023

CRYOWRF—Model Evaluation and the Effect of Blowing Snow on the Antarctic Surface Mass Balance

Varun Sharma, Michael Lehning, Franziska Gerber

The surface mass balance (SMB) of large polar ice sheets and of snow and ice surfaces in general are incompletely understood because of the complexity of processes involved. One such process, drifting and blowing snow, has only been considered in a very si ...

AMER GEOPHYSICAL UNION2023

Reproducibility Dataset for CRYOWRF v1.0

Varun Sharma, Michael Lehning, Franziska Gerber

This repository contains data required for reproducibility of the results to be published in the associated manuscript. Apart from reproducibility, the attached datasets also serve as templates for new users to adopt CRYOWRF in their research. The datasets ...

2023

Southern Hemisphere atmospheric history of carbon monoxide over the late Holocene reconstructed from multiple Antarctic ice archives

Jérôme Chappellaz

Carbon monoxide (CO) is a naturally occurring atmospheric trace gas, a regulated pollutant, and one of the main components determining the oxidative capacity of the atmosphere. Evaluating climate–chemistry models under different conditions than today and c ...

2023

A Case Study on Drivers of the Isotopic Composition of Water Vapor at the Coast of East Antarctica

Michael Lehning, Armin Sigmund, Riqo Chaar

Stable water isotopes (SWIs) contain valuable information on the past climate and phase changes in the hydrologic cycle. Recently, vapor measurements in the polar regions have provided new insights into the effects of snow-related and atmospheric processes ...

AMER GEOPHYSICAL UNION2023

A Snapshot on the Buildup of the Stable Water Isotopic Signal in the Upper Snowpack at EastGRIP on the Greenland Ice Sheet

Sonja Wahl

The stable water isotopic composition in firn and ice cores provides valuable information on past climatic conditions. Because of uneven accumulation and post-depositional modifications on local spatial scales up to hundreds of meters, time series derived ...

AMER GEOPHYSICAL UNION2023

Snow-Atmosphere Humidity Exchange at the Ice Sheet Surface Alters Annual Mean Climate Signals in Ice Core Records

Sonja Wahl

Surface processes alter the water stable isotope signal of the surface snow after deposition. However, it remains an open question to which extent surface post-depositional processes should be considered when inferring past climate information from ice cor ...

Amer Geophysical Union2023

Aerosol and dynamical contributions to cloud droplet formation in Arctic low-level clouds

Athanasios Nenes, Ghislain Gilles Jean-Michel Motos, Paraskevi Georgakaki, Jörg Wieder, Guangyu Li

The Arctic is one of the most rapidly warming regions of the globe. Low-level clouds and fog modify the energy transfer from and to space and play a key role in the observed strong Arctic surface warming, a phenomenon commonly termed "Arctic amplification" ...

Copernicus GmbH2023

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

System for moving a patient

Charles Baur, Loïc Benoît Tissot-Daguette, Hubert Pierre-Marie Benoît Schneegans, Marine Chantal Elisabeth Geneviève Clogenson, Lisa Anaïs Jeanne Bonnefoy

The invention relates to a system (13) for moving a lying patient (P) from a first position to a second position according to a controlled motion comprising a back sheet, a front sheet, each comprising two lateral edges (L1, L2). The system (13) comprises ...

2022

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

Catchment characteristics and seasonality control the composition of microbial assemblages exported from three outlet glaciers of the Greenland Ice Sheet

Tyler Joe Kohler, Martina Andrea Schön

Glacial meltwater drains into proglacial rivers where it interacts with the surrounding landscape, collecting microbial cells as it travels downstream. Characterizing the composition of the resulting microbial assemblages in transport can inform us about i ...

Frontiers Media SA2022

Annual cycle observations of aerosols capable of ice formation in central Arctic clouds

Julia Schmale, Ivo Fabio Beck

The Arctic is warming faster than anywhere else on Earth, prompting glacial melt, permafrost thaw, and sea ice decline. These severe consequences induce feedbacks that contribute to amplified warming, affecting weather and climate globally. Aerosols and cl ...

Nature Research2022

Investigation of new particle formation mechanisms and aerosol processes at Marambio Station, Antarctic Peninsula

Lubna Dada

Understanding chemical processes leading to the formation of atmospheric aerosol particles is crucial to improve our capabilities in predicting the future climate. However, those mechanisms are still inadequately characterized, especially in polar regions. ...

Copernicus GmbH2022

Radar processing techniques to study summer snowfall in the Sør Rondane Mountains, Antarctica

Alfonso Ferrone

Snowfall is one of the main positive contributors to the surface mass balance of the Antarctic ice sheet. There are several techniques to monitor solid precipitation on the continent. Among them, meteorological radars provide the means to characterize the ...

EPFL2022

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

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

Evidence of Strong Flux Underestimation by Bulk Parametrizations During Drifting and Blowing Snow

Varun Sharma, Michael Lehning, Wolf Hendrik Huwald, Jérôme François Sylvain Dujardin, Armin Sigmund, Daniela Brito Melo, Francesco Comola, Koichi Nishimura

The influence of drifting and blowing snow on surface mass and energy exchange is difficult to quantify due to limitations in both measurements and models, but is still potentially very important over large areas with seasonal or perennial snow cover. We p ...

2022

A glacier-ocean interaction model for tsunami genesis due to iceberg calving

Johan Alexandre Philippe Gaume, Ming Gao

Dynamic glacier fracture and the subsequent generation and propagation of iceberg-induced tsunamis are reproduced using a unified numerical glacier-ocean model, in line with observations at the Eqip Sermia glacier in Greenland, as well as laboratory experi ...

SPRINGERNATURE2021