Etude de l'activité électrique des systèmes orageux à l'aide du modèle Méso-NH

Christelle Barthe 1
1 Équipe Cyclones
LA - Laboratoire d'aérologie - LA
Abstract : The electrical scheme of Méso-NH consists of three parts: the electric charge evolution, the electric field computation and the lightning flashes. The non-inductive process is the main mechanism to electrify the cloud. The inductive mechanism becomes efficient when there is an intense electric field in the cloud. When the electric field in the cloud is higher than a threshold value, a lightning flash is triggered and propagates following a bidirectional leader. Branches are generated with a stochastic algorithm and they obey a fractal law deduced from dielectric breakdown models.
Relationships between dynamics, microphysics and electricity are underlined with different cases. Budgets are realized with a tropical squall line in 2D. Simulations of the supercellular and of the multicellular storms are done in 3D with sensitivity tests on the electrification and on the lightning flashes schemes. Then, NOx production by lightning flashes is illustrated on the 10 July STERAO storm.
Document type :
Theses
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00011490
Contributor : Williams Exbrayat <>
Submitted on : Monday, January 30, 2006 - 10:29:27 AM
Last modification on : Monday, April 29, 2019 - 3:28:01 PM
Long-term archiving on : Saturday, April 3, 2010 - 8:06:15 PM

Identifiers

  • HAL Id : tel-00011490, version 1

Collections

Citation

Christelle Barthe. Etude de l'activité électrique des systèmes orageux à l'aide du modèle Méso-NH. Physique [physics]. Université Paul Sabatier - Toulouse III, 2005. Français. ⟨tel-00011490⟩

Share

Metrics

Record views

813

Files downloads

1983