Plasma instabilities in the high‐latitude E region induced by high‐power radio waves

The effect of a high‐frequency powerful pump wave on high‐latitude E region low‐frequency plasma instabilities is theoretically considered. The growth rates and threshold criteria are calculated for instabilities associated with the electrojet (Farley‐Buneman, gradient drift) and with higher‐altitude parallel currents (ion acoustic, ion cyclotron, current convective). The results are discussed in the context of present ionospheric modification (heating) experiments.