Letter | Published:

High frequency radar observations of horizontal plasma waves in the equatorial ionosphere

Naturevolume 277pages203204 (1979) | Download Citation



THE anomaly observed on the magnetic field records in equatorial zones is due to a strong ionospheric current flowing around 105 km, called the equatorial electrojet. We have used coherent radar returns from electron density irregularities embedded in this current to measure electric fields in this region and to study plasma instabilities at the origin of these irregularities. We report here that strong anomalous reversals of the equatorial electrojet are sometimes observed and quasi-horizontal plasma waves have been detected for the first time during such an event.

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  1. Laboratoire de Sondages Electromagnétiques de l'Environnement Terrestre, Bd des Armaris, ‘La Giponne’, 83100, Toulon, France

    • M. CROCHET
    • , P. BROCHE
    •  & C. HANUISE


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