I - Introduction

The INSU/Météo ST radar network is a French network of wind profiler radars (called Stratosphere-Troposphere radar), which are clear air Doppler radars, continuously measuring the three components of the wind above the radar, even in cloud free conditions. The network is made of 5 VHF and 1 UHF clear air Doppler radars operating at 45 (or 72) and 961 MHz, respectively.

(see the explanations of these radars' principles(1.2 Mb PDF file in French!))

This network has been set up by a common support of the Institut National des Sciences de l'Univers (INSU) which is an institute of the French Centre National de la Recherche Scientifique (CNRS), and of Météo-France, the French weather service.

These radars are operated by the following institutes :

1) La.M.P./O.P.G.C.

The Laboratoire de Météorologie Physique is associated with the CNRS , belongs to the Observatoire de Physique du Globe de Clermont-Ferrand (CNRS) and depends upon the Université Blaise Pascal (U.B.P.) of Clermont-Ferrand ,

2) L.S.E.E.T

The Laboratoire des Sondages Électromagnétiques de l'Environnement Terrestre, is associated with the CNRS and depends upon the Université de Toulon et du Var. It has first developed ST radars in France.

3) C.E.T.P.

The Centre d'étude des Environnements Terrestre et Planétaire is a laboratory associated with the CNRS, situated in the Observatoire du Parc de St Maur in the south suburb of Paris and is operating the vertically pointing UHF 961 MHz radar situated in Saint-Santin, half way between Toulouse and Clermont-Ferrand.

4) C.N.R.M./GMEI

The Groupe de Météorologie Expérimentale et Instrumentale is one of the research groups of the Centre National de la Recherche Météorologique, which is situated in Toulouse, and which is the research institute of Météo-France, the French weather service.

5) C.R.A./L.A.

The Centre de Recherches Atmosphériques, situated in Lannemezan near the Pyrénées mountains, is part of the Laboratoire d'Aérologie which is a laboratory associated with the CNRS which depends upon the Université Paul Sabatier in Toulouse and upon the Observatoire Midi-Pyrénées.

6) S.A.

The Service d'Aéronomie is a laboratory associated with the CNRS which depends upon the Université Pierre et Marie CURIE (PARIS VI) situated in the Jussieu campus in Paris. It is operating the VHF 72 MHz radar situated in Saint-Michel l'Observatoire within the park ot the Observatoire de Haute Provence (OHP) in the Alps.

II - Radar Technical Specification

(click on the title in order to obtain the location and the technical specifications of the radars)

III - Data from the Clermont-Ferrand radar

1. Click here in order to get a GIF image of the time-altitude drawing of the last horizontal winds measured by the Clermont-Ferrand ST radar.
2. Click here in order to get a list of the available (for the present time) time-altitude drawings of the horizontal winds measured by the Clermont-Ferrand ST radar.

IV - Scientific program

Our main interests are on the dynamical aspects of troposphere-stratosphere exchanges within mid-latitude cut-off lows or tropopause folds, on the development and test of the Radio-Acoustic Sounding System (RASS) and on the development of data recording and treatment systems.

For these experimental studies, we use :

• the data recorded by the French ST-Radar Network ( click here in order to get a 8 kb GIF image time-altitude drawing of ST horizontal winds),
• the data recorded by Ozone ( click here in order to get a 9 kb GIF image drawing of ozone soundings) and PTU soundings ( click here in order to get a 13 kb GIF image drawing of a PTU sounding)
• the TOMS or TOVS data recorded by orbiting satellites.
• the data produced by the operational model of the European Centre for Medium-Range Weather Forecasts (ECMWF) in Reading (UK), using diagnostic programs based on Potential Vorticity (PV) concepts ( click here in order to get a 25 kb GIF image drawing of a wind and PV map).

One such experiment is the ESTIME ( Échanges Stratosphère-Troposphère et Investigations à Méso Échelle in French, or Stratosphere-Troposphere Exchanges and MEso-scale Investigations in English) described in the presentation made at the Third International Symposium onTropospheric Profiling: Needs and Technologies, Hamburg, Germany, Aug. 30- Sept. 2, 1994.

We have developed a Radio-Acoustic Sounding System (RASS) based on a frequency shift for the received signal. A short description of this system and some experimental results are shown in the poster presentation made at the Third International Symposium on Tropospheric Profiling: Needs and Technologies, Hamburg, Germany, Aug. 30-Sept. 2, 1994.

The INSU/Météo ST radar network is involved in the Mesoscale Alpine Programme (MAP) which is an international research initiative devoted to the study of atmospheric and hydrological processes over mountainous terrain and for which a large-scale field phase in the Alpine region is planned for autumn 1999.

V - Personnel

Four persons are involved in the radar development and operation and in the data recording, treatment and scientific interpretation. A technical team of 6 persons may be devoted to technical tests and improvements.

VI - References

(click on the title in order to obtain a list of our most recent references)

VII - WWW-links

There are several other wind profiler radars in Europe, some of which are accessible on the WEB :

• CWINDE : (COST Wind Initiative for a Network Demonstration in Europe) visualization of the european radar data refreshed every hour)
• Centre de Recherches Atmosphériques (visualization of the Campistrous' VHF radar data refreshed every hour)
• Germany : SOUSY Program
• United Kingdom : UK MST Radar (Aberystwyth)
• Sweden : Esrange MST radar at Kiruna

Y.Pointin@opgc.univ-bpclermont.fr