Publications by Etienne Gabriel Henri Vignon

Assessing the simulation of snowfall at Dumont d'Urville, Antarctica, during the YOPP-SH special observing campaign

Alexis Berne, Etienne Gabriel Henri Vignon

The performance of a set of atmospheric models and meteorological reanalyses in the representation of precipitation days in Antarctica is assessed using ground-based observations such as a precipitation gauge and a Micro Rain Radar during the Year Of Polar ...

WILEY2023

Orographic Flow Influence on Precipitation During an Atmospheric River Event at Davis, Antarctica

Alexis Berne, Josué Etienne Gehring, Etienne Gabriel Henri Vignon, Alfonso Ferrone, Anne-Claire Marie Billault--Roux

Intense snowfall sublimation was observed during a precipitation event over Davis in the Vestfold Hills, East Antarctica, from 08 to 10 January 2019. Radar observations and simulations from the Weather Research and Forecasting model revealed that orographi ...

AMER GEOPHYSICAL UNION2022

Present and Future of Rainfall in Antarctica

Alexis Berne, Etienne Gabriel Henri Vignon

While most precipitation in Antarctica falls as snow, little is known about liquid precipitation, although it can have ecological and climatic impacts. This study combines meteorological reports at 10 stations with the ERA5 reanalysis to provide a climatol ...

AMER GEOPHYSICAL UNION2021

Mixed-Phase Clouds and Precipitation in Southern Ocean Cyclones and Cloud Systems Observed Poleward of 64 degrees S by Ship-Based Cloud Radar and Lidar

Etienne Gabriel Henri Vignon

Mixed-phase clouds (MPCs), composed of both liquid and ice, are prevalent in Southern Ocean cyclones. A characterization of these clouds on fine vertical scales is required in order to understand the microphysical processes within these clouds, and for mod ...

2021

Identification of snowfall microphysical processes from Eulerian vertical gradients of polarimetric radar variables

Alexis Berne, Josué Etienne Gehring, Noémie Planat, Etienne Gabriel Henri Vignon

Polarimetric radar systems are commonly used to study the microphysics of precipitation. While they offer continuous measurements with a large spatial coverage, retrieving information about the microphysical processes that govern the evolution of snowfall ...

COPERNICUS GESELLSCHAFT MBH2021

Challenging and Improving the Simulation of Mid-Level Mixed-Phase Clouds Over the High-Latitude Southern Ocean

Alexis Berne, Franziska Gerber, Etienne Gabriel Henri Vignon, Athanasios Nenes, Georgia Sotiropoulou

Climate models exhibit major radiative biases over the Southern Ocean owing to a poor representation of mixed-phase clouds. This study uses the remote-sensing dataset from the Measurements of Aerosols, Radiation and Clouds over the Southern Ocean (MARCUS) ...

2021

Secondary ice production in summer clouds over the Antarctic coast: an underappreciated process in atmospheric models

Alexis Berne, Etienne Gabriel Henri Vignon, Athanasios Nenes, Georgia Sotiropoulou

The correct representation of Antarctic clouds in atmospheric models is crucial for accurate projections of the future Antarctic climate. This is particularly true for summer clouds which play a critical role in the surface melting of the ice shelves in th ...

European Geosciences Union2021

Microphysics and dynamics of snowfall associated with a warm conveyor belt over Korea

Alexis Berne, Josué Etienne Gehring, Nicolas Jean François Jullien, Nikola Besic, Etienne Gabriel Henri Vignon

On 28 February 2018, 57mm of precipitation associated with a warm conveyor belt (WCB) fell within 21 h over South Korea. To investigate how the large-scale circulation influenced the microphysics of this intense precipitation event, we used radar measureme ...

Copernicus Publications2020

Intercomparison of Large-Eddy Simulations of the Antarctic Boundary Layer for Very Stable Stratification

Etienne Gabriel Henri Vignon, Jing Huang

In polar regions, where the boundary layer is often stably stratified, atmospheric models produce large biases depending on the boundary-layer parametrizations and the parametrization of the exchange of energy at the surface. This model intercomparison foc ...

2020

Measured ice nucleating particle concentrations improve the simulation of mid-level mixed-phase clouds over the high-latitude Southern Ocean

Alexis Berne, Franziska Gerber, Etienne Gabriel Henri Vignon, Athanasios Nenes, Georgia Sotiropoulou

2020

Improved Representation of Clouds in the Atmospheric Component LMDZ6A of the IPSL-CM6A Earth System Model

Etienne Gabriel Henri Vignon

The cloud parameterizations of the LMDZ6A climate model (the atmospheric component of the IPSL-CM6 Earth system model) are entirely described, and the global cloud distribution and cloud radiative effects are evaluated against the CALIPSO-CloudSat and CERE ...

2020

LMDZ6A: The Atmospheric Component of the IPSL Climate Model With Improved and Better Tuned Physics

Etienne Gabriel Henri Vignon

This study presents the version of the LMDZ global atmospheric model used as the atmospheric component of the Institut Pierre Simon Laplace coupled model (IPSL-CM6A-LR) to contribute to the 6th phase of the international Coupled Model Intercomparison Proje ...

2020

Synoptic conditions and atmospheric moisture pathways associated with virga and precipitation over coastal Adelie Land in Antarctica

Alexis Berne, Nicolas Jean François Jullien, Etienne Gabriel Henri Vignon

Precipitation falling over the coastal regions of Antarctica often experiences low-level sublimation within the dry katabatic layer. The amount of water that reaches the ground surface is thereby considerably reduced. This paper investigates the synoptic c ...

2020

Gravity Wave Excitation during the Coastal Transition of an Extreme Katabatic Flow in Antarctica

Alexis Berne, Etienne Gabriel Henri Vignon

The offshore extent of Antarctic katabatic winds exerts a strong control on the production of sea ice and the formation of polynyas. In this study, we make use of a combination of ground-based remotely sensed and meteorological measurements at Dumont d'Urv ...

2020

Improved Near-Surface Continental Climate in IPSL-CM6A-LR by Combined Evolutions of Atmospheric and Land Surface Physics

Etienne Gabriel Henri Vignon

This work is motivated by the identification of the land-atmosphere interactions as one of the key sources of uncertainty in climate change simulations. It documents new developments in related processes, namely, boundary layer/convection/clouds parameteri ...

2020

Microphysics of Snowfall Over Coastal East Antarctica Simulated by Polar WRF and Observed by Radar

Alexis Berne, Josué Etienne Gehring, Nicolas Jean François Jullien, Nikola Besic, Etienne Gabriel Henri Vignon

The current assessment of the Antarctic surface mass balance mostly relies on reanalysis products or climate model simulations. However, little is known about the ability of models to reliably represent the microphysical processes governing the precipitati ...

AMER GEOPHYSICAL UNION2019

On the fine vertical structure of the low troposphere over the coastal margins of East Antarctica

Alexis Berne, Etienne Gabriel Henri Vignon

In this study, 8 years of high-resolution radiosonde data at nine Antarctic stations are analysed to provide the first large-scale characterization of the fine vertical structure of the low troposphere up to 3 km altitude over the coastal margins of East A ...

Copernicus GmbH2019

Transitions in the wintertime near-surface temperature inversion at Dome C, Antarctica

Etienne Gabriel Henri Vignon

In this work we study the dynamics of the surface-based temperature inversion over the Antarctic Plateau during the polar winter. Using 6 years of observations from the French-Italian Antarctic station Concordia at Dome C, we investigate sudden regime tran ...

2019

Large-Eddy Simulations of the Steady Wintertime Antarctic Boundary Layer

Etienne Gabriel Henri Vignon

Observations of two typical contrasting weakly stable and very stable boundary layers from the winter at Dome C station, Antarctica, are used as a benchmark for two centimetre-scale-resolution large-eddy simulations. By taking the Antarctic winter, the eff ...

2019

Importance of the advection scheme for the simulation of water isotopes over Antarctica by atmospheric general circulation models: A case study for present-day and Last Glacial Maximum with LMDZ-iso

Etienne Gabriel Henri Vignon

Atmospheric general circulation models (AGCMs) are known to have a warm and isotopically enriched bias over Antarctica. We test here the hypothesis that these biases are partly consequences of a too diffusive advection. Exploiting the LMDZ-iso model, we sh ...

2019