Publications associées à Reconstructing the Drizzle Mode of the Raindrop Size Distribution Using Double-Moment Normalization

Design of an Open-Loop Pile-Oscillation Program in the CROCUS Reactor

Andreas Pautz, Vincent Pierre Lamirand, Thomas Jean-François Ligonnet, Axel Guy Marie Laureau

As a follow-up to the CEA-EPFL PETALE experimental program on stainless steel nuclear data, the EPFL initiated an open-loop pile-oscillation experimental program in the CROCUS reactor: BLOOM. A reproduction of the critical experiments of PETALE, the progra ...

2024

Euclid preparation: XXVIII. Forecasts for ten different higher-order weak lensing statistics

Frédéric Courbin, Fabio Finelli, Richard Massey, Maurizio Martinelli, Jean-Luc Starck, Gianluca Castignani, Marcello Farina, Austin Chandler Peel, Yi Wang

Recent cosmic shear studies have shown that higher-order statistics (HOS) developed by independent teams now outperform standard two-point estimators in terms of statistical precision thanks to their sensitivity to the non-Gaussian features of large-scale ...

EDP SCIENCES S A2023

Networks with correlated edge processes

Mária Süveges, Sofia Charlotta Olhede

This article proposes methods to model non-stationary temporal graph processes motivated by a hospital interaction data set. This corresponds to modelling the observation of edge variables indicating interactions between pairs of nodes exhibiting dependenc ...

OXFORD UNIV PRESS2023

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

Michael Lehning, Varun Sharma, 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

Higher Order Asymptotics: Applications to Satellite Conjunction and Boundary Problems

Soumaya Elkantassi

Higher-order asymptotics provide accurate approximations for use in parametric statistical modelling. In this thesis, we investigate using higher-order approximations in two-specific settings, with a particular emphasis on the tangent exponential model. ...

EPFL2023

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

Numerical simulations of gas puff imaging using a multi-component model of the neutral-plasma interaction in the tokamak boundary

Paolo Ricci

A three-dimensional simulation of gas puff imaging (GPI) diagnostics is carried out by using a self-consistent multi-component model of the neutral-plasma interaction. The simulation, based on the drift-reduced Braginskii model for the plasma and a kinetic ...

AIP Publishing2022

Snowfall and snow accumulation during the MOSAiC winter and spring seasons

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

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

Estimation of Charge Transfer During Long Continuing Currents in Natural Downward Flashes Using Single‐Station E‐Field Measurements

Farhad Rachidi-Haeri, Hannes Kohlmann, Wolfgang Schulz

The amount of charge transferred to ground during long continuing currents in natural downward flashes can be obtained either through direct current measurements or using remote electromagnetic fields, if direct measurements are not feasible. In this study ...

2022

Wind-Topo: Downscaling near-surface wind fields to high-resolution topography in highly complex terrain with deep learning

Michael Lehning, Jérôme François Sylvain Dujardin

Predicting wind flow in highly complex terrain like the Alps is a challenge for all models. When physical processes need to be resolved in a spatially explicit manner, grids with high horizontal resolution of a few hundred meters are often required and dra ...

WILEY2022

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

Sparsely Observed Functional Time Series: Theory and Applications

Tomas Rubin

Functional time series is a temporally ordered sequence of not necessarily independent random curves. While the statistical analysis of such data has been traditionally carried out under the assumption of completely observed functional data, it may well ha ...

EPFL2021

Leveraging meteorological radars to investigate the influence of atmospheric dynamics on snowfall microphysics

Josué Etienne Gehring

Precipitation is the result of a chain of meteorological processes ranging from the large- to the micro-scale. While the transport of moisture and lifting mechanisms leading to cloud formation are mostly governed by dynamical processes, the formation and g ...

EPFL2021

Radar and ground-level measurements of precipitation collected by the Ecole Polytechnique Federale de Lausanne during the International Collaborative Experiments for PyeongChang 2018 Olympic and Paralympic winter games

Alexis Berne, Josué Etienne Gehring, Nikola Besic, Alfonso Ferrone, Anne-Claire Marie Billault--Roux

This article describes a 4-month dataset of precipitation and cloud measurements collected during the International Collaborative Experiments for PyeongChang 2018 Olympic and Paralympic winter games (ICE-POP 2018). This paper aims to describe the data coll ...

COPERNICUS GESELLSCHAFT MBH2021

Practical issues with modeling extreme Brazilian rainfall

Anthony Christopher Davison, Isolde Santos Previdelli, Paulo Vitor Da Costa Pereira

Accurately quantifying extreme rainfall is important for the design of hydraulic structures, for flood mapping and zoning and for disaster management. In order to produce maps of estimates of 25-year rainfall return levels in Brazil, we selected 893 shorte ...

BRAZILIAN STATISTICAL ASSOCIATION2021

Undercatch Adjustments for Tipping-Bucket Gauge Measurements of Solid Precipitation

Audrey Reverdin

Heated tipping-bucket (TB) gauges are used broadly in national weather monitoring networks, but their performance for the measurement of solid precipitation has not been well characterized. Manufacturer-provided TB gauges were evaluated at five test sites ...

AMER METEOROLOGICAL SOC2020

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

Dynamic Differential Reflectivity Calibration Using Vertical Profiles in Rain and Snow

Alexis Berne, Alfonso Ferrone

The accuracy required for a correct interpretation of differential reflectivity (ZDR) is typically estimated to be between 0.1 and 0.2 dB. This is achieved through calibration, defined as the identification of the constant or time-varying offset to be subt ...

2020

Measurement of R(D) and R(D*) with a Semileptonic Tagging Method

Olivier Schneider, Sun Hee Kim, Tagir Aushev, Mingkui Wang, Chao Wang, Donghyun Kim, Lei Li, Yiming Li, Xiao Wang

The experimental results on the ratios of branching fractions R(D) = B((B) over bar -> D tau(-)(nu) over bar (tau))/B((B) over bar -> Dl(-)(nu) over bar (e)) and R(D*) = B((B) over bar -> Dtau(-)(nu) over bar (tau))/B((B) over bar -> Dtau(-)(nu) over bar ...

2020

Stochastic Super-Resolution for Downscaling Time-Evolving Atmospheric Fields With a Generative Adversarial Network

Alexis Berne, Daniele Nerini, Jussi Sakari Leinonen

Generative adversarial networks (GANs) have been recently adopted for super-resolution, an application closely related to what is referred to as "downscaling'' in the atmospheric sciences: improving the spatial resolution of low-resolution images. The abil ...

2020