Cohabitation between wind farms and weather radars in France
Résumé
Météo-France operates a network of 39 weather radars located in metropolitan France and overseas
territories.
The network is composed of radar operating at C, S and X band, most of the metropolitan radars are
now polarimetric, and have a detection range of to 280 kms.
Weather radars are designed to measure volumetric quantities such as the radar reflectivity (Z 3 ) that
can be related to the precipitation intensity but also the Doppler velocity that is the radial
component of the wind estimated from the displacements of the target contained in the radar
volume volume (hydrometeors, aerosol, insects , etc.)
These radars are subject to false echoes in the presence of wind turbines (WT 5 ) in their coverage
area that lead to overestimations of the reflectivity and false wind measurements that induce in turn
large errors and false alarms on downstream products (eg.QPE) and weather application (analyzes,
forecasts, alerts, etc.) that use radar observations as input.
To limit these false echoes, MF is forced to blacklist the contaminated data when it is detected, but
in the best case scenario that means replacing overestimations by underestimations (linked to the
loss of data).
Since 2011, French regulations protect weather radar wind turbines located within 30 km of
transmitters, but impacts can be observed beyond (80km).
In this communication, the impacts on Météo France products will be illustrated and discussed and
the methodology used to identify the false echoes will be presented. Météo-France will be also very
interested to learn of technical progress or research activity in the field of impact modelling,
signal processing and source reduction (RCS 6 ) that can help mitigate the impacts observed on
weather radar products.
1 - MF :Météo-France
2 - CMR : Centre de Météorologie Radar
3 - Z : factor of reflectivity : https://en.wikipedia.org/wiki/DBZ_(meteorology)
4 - QPE : Quantitative Precipitation Estimation
5 - WT : Wind Turbine
6 - RCS : Radar Cross Section
Domaines
Electromagnétisme
Origine : Fichiers produits par l'(les) auteur(s)
Commentaire : Annexe
Commentaire : Annexe