Publications related to Thunderstorm

Supercell Thunderstorms in the Alpine Region - From Weather Radar Observations to Idealized Modeling

The high-impact nature and increasing occurrence of severe weather phenomena pushes forward research on their occurrence and improving our understanding thereof. Supercell thunderstorms are the focus of much severe convective research, as they represent on ...

EPFL2023

Expansion of the Materials Cloud 2D Database

Nicola Marzari, Giovanni Pizzi, Marco Gibertini, Nicolas Frank Mounet, Davide Campi

Two-dimensional(2D) materials are among the most promising candidatesfor beyond-silicon electronic, optoelectronic, and quantum computingapplications. Recently, their recognized importance sparked a pushto discover and characterize novel 2D materials. With ...

AMER CHEMICAL SOC2023

Nitrogen oxides in the free troposphere: implications for tropospheric oxidants and the interpretation of satellite NO2 measurements

Ilann Ernest Valentin Bourgeois

Satellite-based retrievals of tropospheric NO(2)columns are widely used to infer NOx (equivalent to NO + NO2) emissions. These retrievals rely on model information for the vertical distribution of NO2. The free tropospheric background above 2 km is particu ...

Copernicus GmbH2023

Computation of the attenuation function of the lightning return-stroke current from electromagnetic fields measured in a short-duration time-window — Part II: Numerical implementation

Farhad Rachidi-Haeri, Marcos Rubinstein

In the present paper, we show, by means of numerical simulations, that electromagnetic field data obtained from the radiation of a return-stroke lightning discharge and measured over a short-duration time-window can be exploited to reconstruct the attenuat ...

Elsevier2023

Lightning Localization Using Three-Dimensional Time Reversal MUltiple SIgnal Classification (TR-MUSIC) Algorithm

Farhad Rachidi-Haeri, Marcos Rubinstein, Hamidreza Karami

In this paper a three-dimensional (3D) Time Reversal MUltiple SIgnal Classification (TR-MUSIC) algorithm is proposed to localize lightning discharges. The performance of the proposed algorithm was evaluated considering different scenarios and taking into a ...

2023

Convection of snow: when and why does it happen?

Michael Lehning, Mahdi Jafari

Convection of water vapor in snowpacks is supposed to have a major impact on snow density and microstructure profiles with strong implications for the thermal regime and snow stability. However, the process has never been directly measured and only recentl ...

FRONTIERS MEDIA SA2023

Computation of the attenuation function of the lightning return-stroke current from electromagnetic fields measured in a short-duration time-window, Part I: Theoretical investigation

Farhad Rachidi-Haeri, Marcos Rubinstein

In a recent paper, a procedure to reconstruct the attenuation function of a return-stroke current from the simultaneous measurements of the channel-base current and the radiated electromagnetic fields was presented. One of the assumptions of the whole fram ...

Elsevier2023

Spatiotemporal modelling of extreme wildfires and severe thunderstorm environments

Jonathan Koh Boon Han

Environmental extreme events can have devastating impacts on society when they interact with vulnerable human and natural systems. Such events can result from natural causes, like phenomena related to the El Ni~no-Southern Oscillation or decadal/multi-dec ...

EPFL2022

Convective regimes induced by surface cooling and topography in stratified waterbodies

Damien Bouffard, Tomy Doda, Hugo Nicolás Ulloa Sánchez, Cintia Luz Ramon Casanas

Gravitational convection plays a significant role in the ventilation, heat and mass distribution of aquatic systems. This study investigates thermally driven convection resulting from heat loss at the air-water interface during cooling periods in freshwate ...

Iahr-Int Assoc Hydro-Environment Engineering Research2022

An analytical approximation of urban heat and dry islands and their impact on convection triggering

Gabriele Manoli, Kai Wang

It is well known that cities increase air and surface temperatures compared to their rural sur-roundings, the so-called urban heat island (UHI) effect. However, the associated changes in at-mospheric humidity (also known as urban dry island, UDI) and conve ...

ELSEVIER2022

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

Monitoring Mesoscale to Submesoscale Processes in Large Lakes with Sentinel-1 SAR Imagery: The Case of Lake Geneva

David Andrew Barry, Ulrich Lemmin, Seyed Mahmood Hamze Ziabari, Mehrshad Foroughan

As in oceans, large-scale coherent circulations such as gyres and eddies are ubiquitous features in large lakes that are subject to the Coriolis force. They play a crucial role in the horizontal and vertical distribution of biological, chemical and physica ...

2022

Convection of water vapour in snowpacks

Varun Sharma, Michael Lehning, Mahdi Jafari

This paper studies numerically the convection of water vapour in snowpacks using an Eulerian-Eulerian two-phase approach. The convective water vapour transport in snow and its effects on snow density are often invoked to explain observed density profiles, ...

Cambridge University Press2022

A Characterisation of Alpine Mesocyclone Occurrence

Alexis Berne, Marco Gabella, Monika Feldmann, Urs Martin Germann

This work presents a characterisation of mesocyclone occurrence and frequency in the Alpine region, as observed from the Swiss operational radar network; 5 years of radar data are processed with a thunderstorm detection and tracking algorithm and subsequen ...

2021

Augmenting the performance of impoverished sensor networks using machine learning and time reversal: Application to lightning nowcasting and location

Amirhossein Mostajabi

Lightning is formed in the atmosphere through the combination of intricate dynamic and microphysical processes. Mainly due to this complexity, attempts to solve the important problem of lightning prediction have generally failed to yield accurate results. ...

EPFL2021

Incidence of Upward Lightning Triggered by Nearby Lightning: A Monte Carlo Simulation

Marcos Rubinstein, Antonio Sunjerga, Farhad Rachidi-Haeri

Upward lightning is the dominant type of lightning discharge to tall structures. It has been observed that a significant number of these upward flashes are initiated by nearby lightning activity. The aim of this study is to estimate the incidence of upward ...

2021

On the Initiation of Upward Negative Lightning by Nearby Lightning Activity: An Analytical Approach

Marcos Rubinstein, Antonio Sunjerga

Upward lightning occurs generally from tall structures. The mechanism of the initiation of upward lightning is not yet fully understood. Upward lightning can be classified into two categories based on either the absence or the presence of other lightning a ...

2021

Lightning to tall structures: Characterization, Modeling and Protection

Antonio Sunjerga

Lightning physics is highly multidisciplinary, involving areas such as plasma physics, electrical engineering, meteorology, thermodynamics and particle physics. Upward lightning is a special type of lightning initiated from tall structures that has attract ...

EPFL2021

The laser lightning rod project

Marcos Rubinstein, Antonio Sunjerga, Farhad Rachidi-Haeri, Mohammad Azadifar, Amirhossein Mostajabi, Jean-Pierre Wolf, Clemens Herkommer, Pierre Walch, Thomas Produit

Lightning is highly destructive due to its high power density and unpredictable character. Directing lightning away would allow to protect sensitive sites from its direct and indirect impacts (electromagnetic perturbations). Up to now, lasers have been una ...

2021

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