Crosspolarisation from high-altitude hydrometeors on a 20 GHz satellite radio path

Twenty-gigahertz signals received from the ATS 6 satellite show much higher cross-polarization than expected from rain alone. Radar data indicate the cause to be hydrometeors above, rather than in, the melting band. During thunderstorms, the cross-polar level can change abruptly at the moment of a lightning discharge.