Diagnostics of the magnetosphere and interplanetary medium by means of pulsations

The possibility of diagnostics of the interplanetary magnetic field using the data of ground observations of Pc3, 4 pulsations is investigated. Both empirical and theoretical foundations of this method are discussed. In the shorter-period range (Pc1, Pi1, Ipdp) the methods of qualitative diagnostics of non-stationary processes in the quiet and disturbed magnetosphere are considered. In conclusion, we shall briefly consider the problems, arising when estimating the amplitude of the hydromagnetic waves in the regions of generation.