Simultaneous excitation of large‐scale geomagnetic field fluctuations and plasma density irregularities by powerful radio waves

We elaborate upon the physical mechanism of thermal filamentation instability of radio waves whose frequencies can be as low as in the VLF band and as high as in the SHF band. This instability can excite large‐scale magnetic and plasma density fluctuations simultaneously in the ionosphere and magnetosphere. We comment on relevant experiments in terms of this instability and other mechanisms.