Skip to Main content Skip to Navigation
New interface
Theses

Apport des données polarimétriques radar pour un modèle atmosphérique à échelle convective

Abstract : This PhD has explored the benefits of polarimetric variables (for centimeter wavelength radars), which are sensitive to the microphysical properties of hydrometeors, for convective scale numerical prediction models. In the first part of the PhD, a radar forward operator, consistent with the bulk 1 moment microphysical schemes typically used by the operational convective scale models, has been designed. Comparisons between observed and simulated variables for all radar types (S, C, X) have been performed for two convective cases, and helped validate the forward operator. Following these comparisons, quality controls have been specified so as to limitate the errors on the polarimetric variables before using them for assimilation. In the second part of the PhD, an assimilation method for polarimetric variables, based on the operational 1D+3D-Var assimilation method used for radar reflectivities in AROME model has been designed. The Bayesian retrieval of 1D humidity profiles has been adapted in order to include differential reflectivity and specific differential phase within the observation vector. Different options of the methodology have been tested and evaluated by comparisons with radar and GPS observations. Assimilation experiments conducted for two convective cases demonstrated an impact on analysed humidity fields. The effect of the assimilation of polarimetric variables on forecasted reflectivities and precipitation accumulations was also evaluated.
Document type :
Theses
Complete list of metadata

https://theses.hal.science/tel-01425264
Contributor : ABES STAR :  Contact
Submitted on : Thursday, March 16, 2017 - 11:34:06 AM
Last modification on : Thursday, November 17, 2022 - 4:12:18 AM
Long-term archiving on: : Saturday, June 17, 2017 - 1:21:10 PM

File

2016TOU30056b.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01425264, version 2

Collections

Citation

Clotilde Augros. Apport des données polarimétriques radar pour un modèle atmosphérique à échelle convective. Météorologie. Université Paul Sabatier - Toulouse III, 2016. Français. ⟨NNT : 2016TOU30056⟩. ⟨tel-01425264v2⟩

Share

Metrics

Record views

211

Files downloads

1397